Neural Network "Breeding"

Question: I just watched a Google tech talk video covering "Polyworld" (found here) and they talk about breeding two neural networks together to form offspring.  My question is, how would one go about combining two neural networks?  They seem so different that any attempt to combine them would simply form a third, totally unrelated network.  Perhaps I'm missing something, but I don't see a good way to take the positive aspects of two separate neural networks and combine them into a single one.  If anyone could elaborate on this process, I'd appreciate it.
Answer: Neither response so far is true to the nature of Polyworld!...
They both describe a typical Genetic Algorithm (GA) application.  While GA incorporates some of the elements found in Polyworld (breeding, selection), GA also implies some form of "objective" criteria aimed at guiding evolution towards [relatively] specific goals.
Polyworld, on the other hand is a framework for Artificial Life (ALife).  With ALife, the survival of individual creatures and their ability to pass their genes to other generations, is not directed so much by their ability to satisfy a particular "fitness function", but instead it is tied to various broader, non-goal-oriented, criteria, such as the ability of the individual to feed itself in ways commensurate with its size and its metabolism, its ability to avoid predators, its ability to find mating partners and also various doses of luck and randomness.
Polyworld's model associated with the creatures and their world is relatively fixed (for example they all have access to (though may elect not to use) various basic sensors (for color, for shape...) and various actuators ("devices" to eat, to mate, to turn, to move...) and these basic sensorial and motor functions do not evolve (as it may in nature, for example when creatures find ways to become sensitive to heat or to sounds and/or find ways of moving that are different from the original motion primitives etc...)
On the other hand, the brain of creatures has structure and connections which are both the product of the creature's genetic make-up ("stuff" from its ancestors) and of its own experience.  For example the main algorithm used to determine the strength of connections between neurons uses Hebbian logic (i.e. fire-together, wire-together) during the lifetime of the creature (early on, I'm guessing, as the algorithm often has a "cooling" factor which minimize its ability to change things in a big way, as times goes by).  It is unclear if the model includes some form of Lamarkian evolution, whereby some of the high-level behaviors are [directly] passed on through the genes, rather than being [possibly] relearnt with each generation (on the indirect basis of some genetically passed structure).
The salient difference between ALife and GA (and there are others!) is that with ALife, the focus is on observing and fostering in non-directed ways, emergent behaviors -whatever they may be- such as, for example, when some creatures evolve a makeup which prompts them to  wait nearby piles of green food and wait for dark green creatures to kill them,  or some creatures may start collaborating with one another, for example by seeking each other's presence for other purposes than mating etc.  With GA, the focus is on a particular behavior of the program being evolved.  For example the goal may be to have the program recognize edges in a video image, and therefore evolution is favored in this specific direction.  Individual programs which perform this task better (as measure with some "fitness function") are favored with regards to evolution.
Another less obvious but important difference regards the way creatures (or programs in the case of GA) reproduce themselves.  With ALife, individual creatures find their own mating partners, at random at first although, after some time they may learn to reproduce only with creatures exhibiting a particular attribute or behavior. With GA, on the other hand, "sex" is left to the GA framework itself, which chooses, for example, to preferably cross-breed individuals (and clones thereof) which score well on the fitness function (and always leaving room for some randomness, lest the solution search stays stuck at some local maxima, but the point is that the GA framework decides mostly who has sex with whom)...
Having clarified this, we can return to the OP's original question...
... how would one go about combining two neural networks? They seem so different that any attempt to combine them would simply form a third, totally unrelated network. ...I don't see a good way to take the positive aspects of two separate neural networks and combine them into a single one...
The "genetic makeup" of a particular creature affects parameters such as the size of the creature, its color and such.  It also includes parameters associated with the brain, in particular its structure: the number of neurons, the existence of connection from various sensors (eg. does the creature see the Blue color very well ?) the existence of connections towards various actuators (eg. does the creature use its light?).  The specific connections between neurons and the relative strength of these may also be passed in the genes, if only to serve as initial values, to be quickly changed during brain learning phase.
By taking two creatures, we [nature!] can select in a more or less random fashion, which parameter come from the first creature and which come from the other creature (as well as a few novel "mutations" which come from neither parents).  For example if the "father" had many connections with red color sensor, but the mother didn't the offspring may look like the father in this area, but also get his mother's 4 neuron-layers structure rather than father's 6 neuron-layers structure.
The interest of doing so is to discover new capabilities from the individuals; in the example above, the creature may now better detect red colored predators, and also process info more quickly in its slightly simpler brain (compared with the father's).  Not all offspring are better equipped than their parents, such weaker individuals, may disappear in short order (or possibly and luckily survive long enough, to provide, say, their fancy way of moving and evading predators, even though their parent made them blind or too big or whatever...  The key thing again: is not to be so worried about immediate usefulness of a particular trait, only to see it play in the long term.
Answer: They wouldn't really be breeding two neural networks together.  Presumably they have a variety of genetic algorithm that produces a particular neural network structure given a particular sequence of "genes".  They would start with a population of gene sequences, produce their characteristic neural networks, and then expose each of these networks to the same training regimen.  Presumably, some of these networks would respond to the training better than some others (i.e. they would be more easily "trainable" to achieve the desired behavior).  They would then take the genetic sequences that produced the best "trainees", cross-breed them with each other, produce their characteristic neural networks, which would then be exposed to the same training regimen.  Presumably, some of these neural networks in the second generation would be even more trainable than those from the first generation.  These would become the parents of the third generation, and so on and so forth.
Comment: in fewer words, we are using GA to learn the structure of the neural network (it is still trained as usual with backpropagation to update the weights).
Comment: Thanks for the feedback, but I don't think this is how the Polyworld application works.  It is more like a game where each "character" is controlled by a neural network.  They move, eat, mate and die.  Mating produces a new character that is a combination of the previous two.
Comment: Who the #$%#$ downvoted this? This makes me pretty mad, given that I've actually performed this process myself numerous times. Please explain yourself.
Comment: The description of the relationship between "genes" and "neural nets" in Polyworld is remarkably similar to what I describe in my answer here.
Comment: Sorry, from what Kenny says above it sounds like this is the right idea.  Thanks!
Comment: I realize this is an old discussion, but anyone still interested might want to take a look at the NEAT method developed by Kenneth Stanley, which does in fact do crossover between NNs with different topologies.
Answer: Neural networks aren't (probably) in this case arbitrary trees. They are probably networks with a constant structure, i.e. same nodes and connections, so 'breeding' them would involve 'averaging' the weights of nodes. You could average the weights for each pair of nodes in the two corresponding nets to produce the 'offspring' net. Or you could use a more complicated function dependent on ever-further sets of neighboring nodes – the possibilities are Vast.
My answer is incomplete if the assumption about the fixed structure is false or unwarranted.
Comment: Hello from the future. Geoff Hinton has bred NNs by averaging the weights, or an algorithm of essentially the same effect. He argues that by voting among one or more NNs, you are essentially averaging all the weights. Although this has the effect of destroying the best performing NN, it has the more important effect of creating a NN that is more adaptable and robust to changing environments, exactly the same effect as sexual reproduction.
Comment: Ahh – from a description of Polyword [http://www.beanblossom.in.us/larryy/polyworld.html], it seems that the neural networks are produced, dynamically by another 'genetic' code possessed by each organism in the Polyworld system. It is these genetic codes that are combined during 'breeding' and it is the output of that combination that determines the neural network of the offspring.
Comment: I appreciate your feedback.  The idea of averaging is interesting if you can count on a fixed structure.  From the video, it appeared that the structure was not fixed, because nodes can be added/removed as mutations.  However, this is a good starting place.
Comment: @MusiGenesis – I can't upvote you (yet), but your answer is correct and matches my own (amended) answer [see above comment].
Comment: @Kenny: interesting link, but your link is broken (I had to remove a "]" from the URL).
Comment: @Kenny: thanks. Normally downvotes don't bother me, but the bizarrely inexplicable ones do. It's not like this question ("how would one go about combining two neural networks?") has an easy, simple answer anyway.
Comment: The answer posted by @mjv provides even more details about Polyworld and other AL/ALife (Artificial Life) software – but the answer to the original (and current) question is still that the neural networks are produced by other code and it is chunks of that other code that are combined to produce offspring.
Comment: Just in case this question hadn't already been answered to death: a concrete answer will depend on (a) the nature (e.g. data structures, etc.) of the genetic code that is responsible for variation in the neural networks; and (b) the algorithm by which the genetic code for two organisms are combined.
Based on the answer from @mjv, apparently the genetic code itself is of a regular (fixed) structure, i.e. specific 'genes' (code chunks) encode specific attributes of the neural network.

Neural Network "Breeding"


Making a dip ahead of time

Question: I would like to make a chunky dip using cooked broad beans, olive oil, white vinegar and Parmesan. Would mixing it together, covering and storing it in fridge for several hours in advance, keep the texture and flavours fresh?
Comment: Please could you refine the question, how long do you wish/plan to store before use?  Several hours is an ambiguous descriptor.  Definition of several: More than two, but not many.  Prior to cooking, the broad beans were raw, frozen, dried?  These details may affect the answer and the relevance.
Comment: Sounds like a hummus sort of dip? You say chunky... do you mean blended but not smooth or just whole beans?
Comment: Thanks, I agree I did not give enough info. I will use frozen beans,  cooked, shelled and forked to give a slightly mashed texture to spread on toast. I would like to cover and store in the fridge for 3 hours then bring back to room temp. to serve.
Answer: Vinegar will start changing the flavor and texture of your dip from the moment you add it. Putting your dip in the fridge might slow down the process, but it will still happen. Is adding the vinegar right before serving your dip a possibility?
Also, keep in mind that if you want your dip's texture to be just as when you made it, you need to bring it back to room temperature before serving it. Olive oil in particular can coagulate at low temperatures, so keep that in mind.
Comment: And the starches from the beans behave much differently when cold than when warm ... but overheating might cause problems with the cheese.

Making a dip ahead of time


Should we de-latinize questions?

Question: Several of @Masi's anatomy questions (e.g., here1 and here2, among others) are written with latin anatomy terms. Should we turn them into standard english? No one in the English speaking anatomy world uses the term this way.
Answer: Latin has been lingua franca in medicine for many centuries and even millenia. I am surprised to read that the "English speaking anatomy world" doesn't use Latin and can assure, that Russian- and German speaking worlds do extensively use latin-based terminology.
The most common reason to use latin is because this terminology is highly unified. As long as you use the classical nomenclatures, BNA or PNA, everyone irrespective of hier or her native language immediately understands you.
I would even suggest the opposite -- for anatomy questions requiring deep knowledge of this subject I would intentionally latinize the question: latin terms are often used in search queries and would make questions easier to find.
Answer: If the user writes the latin terms, he's probably somewhere where the latin terms are still used. Removing them wouldn't be a good idea in this case.
Adding the english terms to the latin terms would be the best solution.
Answer: The Latin terms are still the standard Medical terms according to medical people. We don't call E. coli something else.
Comment: What's the source of this? If I read Lancet, I don't see Nomina Anatomica terminology.
Answer: Unfortunately, this is a site with a very broad range, in "biology" we have (in roughly descending order of professionalism, and not exhaustive at all):

academic biology

macrobiology
microbiology
ecology / evolutionary biology
physiology

medicine (for professionals)
health (for normal people)
hobbyist curiosity

Given the wide range, it's probably best to aim the terminology at the reader. (If someone is asking if they can sleep every other night and still be healthy, no need to phrase the answer in Latin)

Should we de-latinize questions?


Error installing Microsoft SQL server 2008 R2 with tools! Error code

Question: When trying to install SQL Server 2008 R2, I get the following error:
Error installing Microsoft SQL server 2008 R2 with tools! Error code: -2068578303
Does anyone know what this means?
Comment: Can you give us some more information. Like what you have found out from searching on this, or anything different that you may have been doing. Have you checked the installation log?
Answer: Error code: -2068578303 translates into hex 0x84B40001 which corresponds to an error in the SQL Server setup command line.  You can likely find the answer to your problem at:
http://msdn.microsoft.com/en-us/library/ms144259%28SQL.100%29.aspx
Answer: I encountered this error when installing from an ISO mounted as a DVD drive. When the same installation files are copied from the mounted image into a local folder, and setup is run from the local folder, the error no longer occurred.


Identity Leakage - Universal Financials

Question: I did my 2018 tax return with Universal Financials, LLC, and I got my tax review copy online. Then one of my colleague came and said he also did tax return filing through the same agency and he got my tax review copy, which includes my name, address,social security number, and other tax related info. So I dont know how to protect my details from others and also is that details shared to anyone else or not. Is there any way to ask for the compensation to the above said agency? or should I ask the agency to provide me a documented agreement saying that if anything happens in future, they will take the full responsibility. Or shall I move a legal case against them?
Answer: According to the Terms and Conditions of Universal Financials' site - which you agreed to when you used their service by "click signing" a contract - they state that they are not liable for the security of your personal and financial information.
You could take them to civil court for damages, but your contract with them absolves them of liability. And, they would surely not sign an individual contract with you to safeguard your information in the future, as that would open them up to signing such a contract with all users and as a result be liable for data leakage.
Your only recourse is to not use their service; their recourse is to close your account.

Date Security & Integrity:
MetaFin Consulting, LLC has reasonable technical and organizational
  Security measures in place to protect personal information against
  unauthorized disclosure or access and against any other unlawful forms
  of processing. However, these measures are not absolute. In addition,
  the transmission of data over the Internet by its nature entails the
  use of systems under the control of third parties, and as a result
  MetaFin Consulting, LLC cannot ensure the security of such systems.
Force Majeure:
MetaFin Consulting, LLC is not responsible for any delay or failure in
  performance of the website in whole or in part for any reason
  including, without limitation: fires, floods, storms, earthquakes,
  civil disturbances, disruption of telecommunications, hacker attack,
  governmental action, computer viruses, data corruption, incompatible
  or defective equipment, software or services or otherwise.
Comment: tbh just because they write it in their terms of service doesn't releases them of their liability. Like you can't write down "if I accidentally kill you I'm free from any liability". Pretty sure OP could take them to court and court would remind the company to be more cautious with personal data. No fine but a scolding.

Identity Leakage - Universal Financials


Cartan subalgebras in the group algebras of virtually abelian groups

Question: Let $G$ be a virtually abelian group. Are there any general results on the existence or non-existence of Cartan subalgebras in the generated group $C^*$-algebra or group von Neumann algebra?
Comment: Are you restricting attention to discrete groups?
Comment: I'm interested in any result on virtually abelian groups, so a (maybe partial) answer in the discrete case would already be nice
Answer: For von Neumann algebras in the discrete case Cartan subalgebras always exist. Indeed, if we only assume that the group is amenable then its von Neumann algebra is finite and injective, so it is of the form $\bigoplus_{n \in \mathbb{N}} A_n \otimes R_n$, where $R_1=\mathcal{R}$ is the unique hyperfinite $\mathrm{II}_1$ factor, $R_n=M_n$ for $n\geqslant 2$ and $A_n$'s are abelian. Each $R_n$ is known to admit a Cartan subalgebra; for matrix algebras you just use the diagonal matrices and $\mathcal{R}$ can be presented as a crossed product, e.g using an irrational rotation. It suffices now to tensor these Cartan subalgebras with $A_n$'s and the direct sum will give a Cartan subalgebra.
EDIT:
In the locally compact case (for von Neumann akgebras) the answer is also affirmative. Indeed, if a locally compact group is amenable then its von Neumann algebra is injective (but the reverse implication does not hold in this generality). What is more, if a locally compact group admits a finite index unimodular subgroup, then it is unimodular, so our group is unimodular. It follows that the Plancherel weight is tracial, hence the algebra is semifinite. Therefore the only difference with the discrete case is that there might be a type $\mathrm{II}_{\infty}$ summand. But a type $\mathrm{II}_{\infty}$ injective von Neumann algebra is of the form $A\otimes \mathcal{R} \otimes B(\ell_2)$, so it also admits a Cartan subalgebra.
Comment: I think we can do slightly better: if G is locally compact and virtually abelian, all irreducible unitary representations of G are finite-dimensional, with a uniform bound on the dimensions. I think one can then deduce by the method of polynomial identities that VN(G) embeds into a finite Type I algebra, but I haven't checked the details or the literature
Comment: @YemonChoi, yes, that sounds reasonable. Maybe that also helps handling the $C^{\ast}$-algebraic version of the question, which I haven't considered in my answer. If I remember correctly, any MASA in a type I algebra is regular, so it would seem that all expected MASAs are Cartan.


Can I have a separate notification sound for my Twitter alerts

Question: As above, I want a different sound for incoming Twitter alerts so they are not the same as my normal texts. It's so frustrating to keep looking at the phone when I am waiting for a particular private text, but I dont want to get rid of my Twitter alerts. Surely like email sound can be different this should be too. How do I do it please? I have an HTC Sensation.
Answer: In the Twitter app...

Tap the Overflow menu (three vertical dots) and choose "Settings"
Tap the account (your username, not general) you want to change
Under "Notification Indicators" tap "Ringtone"
Choose the Ringtone you want to use for Twitter notifications for this account

For more recent versions of Twitter, this something controlled at the OS level.

Long-press the app icon and choose App Info, or go to Android Settings, Apps & notifications, and choose "Twitter"
Tap "App notifications"
There, for each Twitter account, you can control which notifications you get, whether they make a sound, and whether they also show a pop-up
Tap the notification you want to change, make sure "Make sound" is on, and then tap "Sound" to choose the alert ringtone for that notification.

(These instructions are based on Android 8.1 and Twitter 7.40.0.)
Comment: This doesn't work for me in Twitter Version 7.14.0. There is no overflow menu, and Settings->Notifications has nothing for Ring tone. Android 7.0 on Samsung Galaxy S8+.
Comment: @EugenevanderMerwe: Do note that this answer is from 2013. The app has obviously changed a lot since then. I'll see if I can add more recent instructions.
Comment: I've added instructions based on Android 8.1 and Twitter 7.40.0. Depending on your OS and app versions, this may vary.
Comment: But strangely it is not working. Only default ringtone is getting applied even after I changed it a thousand times.
Comment: Yep not working. No overflow menu, no username or general section as indicated, only enable sounds effects and this defaults to the system sound. How about posting a screenshot?


In GIMP, what is the equivilent to adding a 'spot channel' in PS ? Need a white layer below image and edges transparent for printing

Question: I am looking to print an image with a white layer behind the color image.  The image is of a face with the background in transparent.  When it get's printed, it goes on a dark wall and therefore I wish to lay down white prior to the color layer.  Apparently this can be done in Photoshop using a spot channel.  When I google 'spot channel GIMP' I get info on channels but nothing specific.  I am a rookie with GIMP, but really want to give it a chance.  Any help would be appreciated.  All exports have todate been Tiff files and the transparency begins printing in black, with no white layer behind. In the image below, the white wall area of the wall is the transparent region.
Again, the idea is The Wall Printer lays down an area = to the facial region in white and prints the actual facial image in color over top the white, because it's going onto a dark wall color. This can be done with PS, i'm just trying to prove it can happen with GIMP as well.  Any help would be greatly appreciated.
Comment: Have you checked with the printer if it's actually possible to print white? This is not just a digital issue, but also a physical one.
Comment: I don't believe GIMP supports CMYK, at least not natively. You sort of need CMYK support for spot colors. But that doesn't necessarily mean you can't simply create an underlying shape and print it first, then print the rest of the piece. It doesn't *have* to be white.. it can be any color on screen.. merely tell the print provider to use white ink (see Wolff's comment though).
Comment: The printer does print white, yes.  I'll try to create a copy of the user video for photoshop if I can and provide a link.
Comment: You make a good point Scott, but the entire idea is to let the printer do the work all in one shot, rather than performing two print processes and having to accurately line up the the secondary application to overlay the 1st one.
Comment: It might have to be that I acquire a license for PS in order to print images in this manner.
Answer: GIMP has no spot colour channel support, nor does it support CMYK images used for print separations. To be honest, GIMP is not ideal for print work. Also note that CMYK printing doesn't involve the use of white Ink. So you'd need to check that requirement with your print supplier to find out what's possible.  It would have to be created in such a way that a white separation can be done, assuming your printer is capable of printing it.
It might be possible to improvise a bit however.
You could fill a selection white under your transparent image layer, and duplicate that layer invert it, and merge it with a white layer under that to give you a usable white separation which your printer will need.
Here's an example

As for the CMYK problem, you could open the GIMP XCF file in Krita (which is also free and open source) and convert it to CMYK, since Krita does support CMYK. Then assuming your printer has Photoshop, you could export it as a PSD (Photoshop Document). The layers will be preserved, and your printer will have access to the white separation layer.
Another possibility would be to export the finished GIMP work as a PSD (Photoshop Document) directly.  Again, if your printer has Photoshop they could easily convert it to CMYK for you. It only takes a second.
Comment: I did create the white layer, but did not create the white separation layer (inverted) as you are demonstrating above.  I'm going to give that a go and attempt to use Krita as you suggested to convert to CMYK.  We are using Maintop software to print the file to a .prn file before printing, as long as Krita can preserve the layers exporting to a file that Maintop recognizes (usually we use a tif, jpg), in theory it could work.  Will update.  Thanks for the tip Billy.
Comment: Well, I tried your suggestion Billy.  Unfortunately I get a dialogue box in Krita that says: "Could not open file: [path][name].xcf"  "This XCF file is too new; Krita cannot support XCF files written by GIMP 2.9 or newer.:
Comment: @FaronFowler Then instead try the second method. Export as PSD directly from GIMP.  Krita can also open PSDs. Layers should be preserved. Then you could convert to CMYK in Krita.  I've no idea what Maintop is. But Krita does support CMYK TIFFs, although I'm not sure if it supports TIFFs with layers. You could perhaps output a separate TIFF for the white layer, and a CMYK TIFF for the coloured image.
Comment: update:  I downloaded an older version of GIMP to my laptop 2.8.22 and reworked the image as per the layering discussed..  The xcf does open in Krita.  I exported 3 images from Krita after converting the image to CYMK non flattened.. .a tif, a jpg, and a psd.
Comment: Upon loading those images in Maintop and printing to the .prn file, I am finding that the tiff files generate an error.  The psd and jpg file do print... The jpg printed with full transparency on the outside as expected and the image centered looks good as well.  The initial test was very small however and not on the darkest backdrop so I am having trouble deciphering whether or not the white layer is being printed.  I will test again on a darker surface...likely black... to see if I can realize the same image in the same manner on a darker backing (i should see the white layer more clearly).
Comment: @FaronFowler If that's a home inkjet or colour laser printer, they don't print white. It's not part of the normal "CMYK" printing process. White is non-printing in CMYK. You'd need to use a different print process, such as screen printing. I already alluded to this in my answer when I said "assuming your printer is capable of printing it".
Comment: @FaronFowler Watch this. [CMYK+White screen printing on a black t-shirt](https://www.youtube.com/watch?v=X0QZ7n2qAwk) as an example of what I mean.
Comment: hey Billy, the printer definitely prints white... it's probably something small that I am not doing correctly.  I am able to print the image properly, just doesn't lay down the white layer, but I am only able to export into jpg or psd and not tif nor gif, it errors out the Maintop software when trying to generate the .prn file otherwise.   So maybe it's something to do with the file generation.  Anyway, here is the printer I am using...  https://www.youtube.com/watch?v=9zBgk58Dnls
Comment: Sorry, but this sounds like it's hardware specific. Maybe get support/advice from the manufacturer. Hardware support is off-topic here. Sorry about that.
Comment: No worries, thanks for the guidance.  We will use PS for the time being.


Photoelectric effect with protons

Question: Is it possible to make a metal plate emit protons (not electrons) when it is illuminated with light? If possible, how?
Comment: You could improve this question by stating what you believe and your reasoning/rationale. But I do like the question!
Comment: Probably not with normal visible light.  Protons are either tightly bound in a nucleus or tightly bound with an electron.
Answer: No. Electrons are very loosely bound while protons are are held together by the strong force. It would take an enormous amount of energy to eject a proton  and does not actually surmount the potential barrier of the strong force it merely tunnels through it (this is called proton decay). For electrons, which are bound to the nucleus by electromagnetic force, have a potential barrier that is much, much easier to surmount. This is why electrons get ejected and not protons.
The strong force is roughly 137 times stronger than the electromagnetic force. This approximately means the barrier that the proton needs to over come is 137 times larger than the electrons barrier.
Please note the comments for additional insight. Thanks @JohnRennie, @yatima2975, and @BrandonEnright!
Comment: I suppose if you could make your photon arbitrarily energetic there would come a point where protons were ejected. However it wouldn't be a clean process like photoemission - you'd just be destroying the atoms on the surface.
Comment: The nuclear binding energy per nucleon is on the order of a couple of MeVs, while the electron binding energy for the outermost electron is in the tens of eVs. I don't know why you're mentioning the inverse of the fine structure constant here!
Comment: @yatima2975 : you can say that the electromagnetic force is "proportional" to the fine-structure constant (or that the fine-structure constant is an adimensional measurement of the strength of a force). In the case of the strong force, this value is close to 1.

This said, the fundamental difference here is the distance: nucleons are tightly packed, whereas electrons are far far away, and partially screened. Therefore, the energies have much higher ratios, as you said.
Answer: As jerk_dadt said, protons are much more tightly bounded in the nucleus by the strong nuclear force. Furthermore, photoelectric effect happens typically on metals, where the most external electrons are "floating" in no-mans land between the atoms, not tightly bound to any of them. So, the bonding for the protons is way stronger than 137 times. But we can assume you can generate a photon sufficiently energetic.
Let's revisit what happens when you shoot a UV photon to your metal. It first encounters the electrons, and if it gets absorbed, it will increase its energy, move at a high speed and be scattered until it gets outside of the metal. The shift in momentum (from going towards the surface to going away from it) gets absorbed by the rest of the structure. It is really tiny, and dispersed across several scattering processes, so not a big deal.
But now you have your super-energetic photon. The cross-section for the photon-electron scattering decreases with the energy of the photon, so you could assume it passes through the electronic shell without a problem. It now hits the nucleus, that offers a much broader target and gets (at least partially) absorbed. Then, suddenly, the protons inside will have a high energy and start moving. The strong interactions are quite complicated and a detailed calculation of what would be exactly going on is difficult, but for sufficiently high energy photons, you will excite the atom so much it would split. If the energy is high enough, you will also create pairs of particles than will take away part of the energy.
The fragments will follow what is energetically favorable, so my guess is you will get two fragments roughly similar in size, as you do in most radioactive decays.
Let's assume the original metal was iron, the most efficiently packed nucleus. The new fragments have a much higher energy than the original, so the fragments will not have much kinetic energy and move slowly. They will attract the electrons around them and try to bond chemically with the material around.
But if you had say, uranium, the two fragments will have much less energy than the original, so they can actually move fast (minus the energy taken by neutrinos, photon emission and so on), and they could get to escape the solid.
Answer: I would think it is possible that a photoelectric effect might occur in proton conductors where the protons are not tightly bound, but free to move around.
Another situation where they are relatively free to move around is in certain hydrated metals, particularly palladium. If the loading factor of hydrogen is high enough in a palladium lattice, perhaps a photoelectric-like effect for protons can be observed at the surface. I suppose that the electrons are still the primary current carriers in this case, and so hydrated metals are not considered "proton conductors", despite the high mobility of the protons. If I were to venture a guess, it would be that the work function for the mobile protons would be about the same as for the electrons, and so the ratio of the number of protons emitted to the number of electrons emitted photo-electrically would just be proportional to the ratio of the density of states for the two particles at the surface.

Photoelectric effect with protons


What exactly is "logical justification"?

Question: I read and hear the term "logical justification" and I can't find a definition for it. Is it as pedestrian as it sounds (can be put in the form of logic and makes a valid argument), or is it a term of art? When a philosopher insists that there is no such thing as "empirical justification" and that the "only justification is logical justification", I'd like to know just what exaclty the latter is. I am concerned with the "logical" part of the term.
Answer:
What is "logical justification"?

In philosophy the term justification usually is used in the context of :

the justification of propositions and beliefs. [...] When a claim is in doubt, justification can be used to support the claim and reduce or remove the doubt. Justification can use empiricism (the evidence of the senses), authoritative testimony (the appeal to criteria and authority), or reason.

Thus, we may assume that "logical justification" means the justification of a claim by way of a deductive argument.
This means, inferring the claim (a proposition) from some premises with a valid logical deduction.
Obviously, every argument needs premises: thus, the "strenght" of the logical justification supporting the claim depends on the level of certainty of the premises.
Comment: So I think you are saying that it's "can be put in the form of logic and makes a valid argument" as I suspected.
Comment: @DHD I know this is an old message, but you never got a straight reply, so I thought an example might help. A: "Your pen is on the table. [claim] I see a pen is on the table. It looks like your pen. (The support is specific to the claim.) Perception is widely agreed to accurately represent objective reality. (This explains that the support is accurate and matters.) [all of this is justification]" B: "That's not my pen. (Denying the claim.) It's blue, but mine is red. [justification] Maybe there's something wrong with your eyes. [counter to A's justification]"


Did Alita make enough for a sequel?

Question: Its budget according to google said it was 200 million. Worldwide in the box office it made over 400 million but I keep finding articles that say it may break even or even be a loss? How is that possible when it doubled its budget? Is it taxes not figured in? Was it a success? I loved the film. I dont want to see it be a golden compass and end without a sequel.
Comment: Welcome to Movies.SE! You're asking multiple questions here, and some of them seem opinion based. Different people will have different opinions on what constitutes "financial success" or "enough to justify a sequel".
Comment: Another factor to consider is not all reported budgets include marketing which can often be about as much as production costs. I'm afraid I'm going to VTC, but don't be dissuaded. Happens to all of us. Please stick around; it's a pretty great community.
Comment: @K Gibson  The worldwide gross is the total amount paid to many thousands of theaters worldwide.  Each theater keeps a portion of that gross to pay expenses and possibly make a profit, and sends a portion to the distributor and/or the production company, according to various distribution deals.  The production company/companies only makes a profit if their share of the worldwide gross is larger than the production cost and marketing costs, and the film is only considered successful if the production company makes a significant profit.
Comment: If a company spends $200 million on a movie (and likely somewhere between $100-$150 million on advertising et al) just to barely earn back your costs. These kinds of movies are supposed to make a billion or so to kick off a franchise. (And Golden Compass was really bad and completely ignored the core of the book. Oh, and that book series is now a BBC/HBO series.)
Answer: The production budget for the film was about $200 million, but that only covers the costs of actually making the movie.  That does not include other costs related to the movie, such as advertising budgets and interest paid to whoever funded the film.
Comment: I always thought that $400M was the theatre gross and the individual theatre's profits need to reduce it; aka artificially inflated for hype.

Did Alita make enough for a sequel?


AJAX load of a rendered PNG not working

Question: I am rendering a custom image based on some defaults and parameters in POST with a custom php script and the GD library.
I am trying to build a custom form to allow users to select these parameters and then send an AJAX request to render the image and send it back and load a preview in the page.
The problem is that the first preview works, but after that I can not load any more previews. I just keep seeing the same image in the preview window. However, I am writing the image to disk and that is being updated just fine, so I image this is some apache or browser caching. Here is some code:
AJAX request is like
<code>preview = new Image;
preview.src = url;
$(preview).load(preview.src, imagedata, function() {
   $('#gaga-preview-space').html(this);
});
</code>
Where imagedata is an array with bgcolor, etc. I am also generating a timestamp for each request, in hopes that it would stop apache from cachine the response. This has worked in other instances, but not this one.
The php generation script looks like:
<code>// Save file
$file = "/var/www/tribegaga/sites/all/files/gaga_customization/test.png";
$result = imagepng($image, $file);

// Spit out file
header("Cache-Control: no-store, no-cache, must-revalidate, post-check=0, pre-check=0");
header("Pragma: no-cache");
header("Content-Type: image/png");
imagepng($image);

imagedestroy($image);
</code>
You'll see I'm sending some headers, but those aren't the issue either.
Perhaps I'm on the wrong path with thinking it is caching. But as I mentioned, the .png generated works fine.
Update: Ok the issue was that the browser doesn't POST to get an image, it GETS, so now my script sends a GET string and it all works wonderfully. But I'd rather not have an image src=http://site/script.php?string=params&test=foo etc.
If you all have any suggstions I'd appreciate it.
Thanks!!
Answer: You could try setting an Expires (to a date in the past) and Last-Modified (to the current date/time) header too.

AJAX load of a rendered PNG not working


Are Speculative Shares safe?

Question: I am a beginner investor. I have seen some speculative shares where I saw a potential of profit earning. But I am scared of the risk.
So I want to ask if I need to be aware of something while trading in these stocks.
Comment: Speculation is by definition less safe than investment, which is less safe than a high-rated bond, which is less safe than a government- backed bond out government-insured bank account. Increased potential for profit is always balanced by increased risk of loss. You need to pick something, or more commonly a mixture of things, that balances this at a level you're comfortable with. Speculation, if you want to play with it at all, should not exceed an amount you would be willing to lose if it doesn't work out.
Comment: @keshlam +1 for the definition of speculation.
Answer: You're right to be concerned with the added risk of speculative shares. Understand your investments! Consider limiting your risk until you have experience investing. The worst outcome would be to lose your capital and stop investing.
Speculative stocks will have higher volatility. Their valuation typically soar in a bull market, but suffer high losses in economic downturns when investors rush to the safety of larger companies, bonds, or cash.
Answer: If you are scared of the risk then you should not invest in them.
If you are looking for some 'secret' about these securities… there isn't any.
I use high Beta (volitile) securities when I speculate.
If you want protection against inflation and safety then invest in I-series Treasury bonds.  They earn (just a little bit) of interest above and beyond the inflation rate. Couple that with the tax deferred nature of an IRA and you will not lose money. Here  is a link to a description of I series bonds.
If you do it in a 401(K) then you get the benefit of the employer match as well as the tax deferred benefit.
Comment: +1 from me, for the sentiment behind that first line. The DVer should comment on why he takes issue with this answer.

Are Speculative Shares safe?


Are Spyder formatting warnings important and, if not, how to disable them?

Question: I am learning to use Spyder and find my code in the editor is riddled with nit-picky white space warnings:

no space after comma, not enough space before a comment, too much space at the end of a line, my comment line is too long, etc.
I have not found any of these to be a problem with Python before (e.g. in Jupyter) and, thus far, ignoring the warnings has not affected how my code is running in Spyder.
Is there any real danger if I ignore these warnings?  If not, how can I turn them off?  They are distracting and would bury useful warnings--should Spyder have any useful warnings.
Spyder 3.2.0, Python 3.5.3, IPython 6.1.0, Windows 8.1 Enterprise 64 bit.
Comment: These warnings are Python PEP8 warnings by the way which promotes [generic conventions about the Python coding](https://www.python.org/dev/peps/pep-0008/).
Answer:
Is there any real danger if I ignore these warnings?

No, they are style warnings so you can safely ignore them.

how can I turn them off?

Please go to
Tools > Preferences > Editor > Code Introspection/Analysis

and deactivate the option called
Real-time code style analysis


Odoo Community Software as a Service

Question: Excuse my ignorance in law and licensing, I have an inquiry regarding Odoo Community Edition that's licensed under LGPLv3, I am planning to develop some addons for it to be suitable for a specific market on top of the Odoo Community Edition, and sell it as a SaaS solution, the customer will have no access to the servers or code, only the software as a service with a monthly subscription, is this break the license terms for Odoo Community ?
https://www.odoo.com/documentation/16.0/legal/licenses.html
Comment: https://opensource.stackexchange.com/
Answer: As long as an (L)GPL-based program does not leave the server, its sourcecode  doesn't need to be conveyed to anyone.
That's commonly referred to as the "server-sided loophole" in the (L)GPL. There is a license that was designed specifically to address this concern: The Affero General Public License (AGPL). It's basically the GPL, but with the additional clause that the software with its sourcecode must also be licensed to "all users interacting with it remotely through a computer network". This is actually the license Odoo was distributed under until Version 8. But from version 9 they moved to the LGPL which does not contain this clause.
It appears that what you want to do is exactly what was intended by Odoo S.A. when they switched from AGPL to LGPL. More information on this article on their website:

Contributors would need to give a lot to enrich the Odoo offering, while getting little in return under the current licensing, as they are not system integrators (and as such do not benefit from fees on services), and under current terms cannot sell modules with the required legal security. Therefore, we will progressively move Odoo from an AGPL license to a LGPLv3 license.
[...]
In summary, the benefits are as follows:

We can open up a true 'App store' to the benefit of both customers and publishers willing to invest in fully packaged, ready-to-use apps as long as they get some financial compensation. This is key for our CMS & Ecommerce but will benefit other apps too.

End users will be able to use standard proprietary modules published by large companies that are key for their business (e.g. UPS/Fedex connectors for ecommerce shipping).

The license remains 'Copyleft' which means we retain  solid protection provided by  those types of licences.

Customers using the CMS do not need to fear having to release the whole source code of their Odoo implementation to every website visitor.

The license is compatible with AGPL v3 which means that modules under this licence will continue to be usable with Odoo. We however advise current owners to migrate to LGPLv3 too.

Odoo Community Software as a Service


Ramanujan's personification of small positive integers

Question: I dimly recall reading somewhere (perhaps in "The Man Who Knew Infinity"?) that Ramanujan associated personalities (perhaps it was mystical personalities, e.g. specific gods and goddesses?) with small positive integers. Is there a list of of which numbers were associated by him with which personalities?
Answer: According to The Man Who Knew Infinity, Ramanujan dealt with the quantity $2^n-1$. According to him:
When $n=0$, the expression denotes nothing.
When $n=1$, the expression denotes unity, the Infinite God.
When $n=2$, the expression denotes Trinity, the three demigods of Hindus: Brahma, Vishnu, and Maheswar (Shiva).
When $n=3$, the expression denotes Sapta Rishis.
For further reading see, Ramanujan Memorial Number, Vol. 1, Letters and Reminiscences and Ramanujan Memorial Number, Vol. 2, An Inspiration, Madras: Muthailpet High School by P. K. Srinivasan.
Comment: https://en.wikipedia.org/w/index.php?title=Bhutasamkhya_system&oldid=545866328 — using things there are $n$ of, to denote the number $n$, was a standard practice in classical Indian mathematics. I'm not sure whether Ramanujan had encountered any classical Indian mathematics though, so I have a tiny suspicion that the author of _The Man Who Knew Infinity_ just got things a bit mixed up. (Or maybe Ramanujan did arrive at the same convention by himself; we know he did that with a lot of mathematics!)


Photomultiplier pulses only at first few channels?

Question: I have an old Hamamatsu PMT, and I have a scintillator that can detect neutrons, gammas, alphas. But no matter what source I use, I'm only seeing counts at the first few channels (up to about the 15th channel) and then no counts for any of the other channels. I've been using this PMT since a while ago, and previously it would show counts (for the same source and same conditions) upto channel 700 even. What could be an issue to investigate? I only have one PMT.
Comment: You've likely either lost optical coupling or lost a lot of gain in the PMT. You can dismount the PMT and text it in isolation, but the PMtT may be toast. Did you make mistake with it (HV on while exposed to room light, knocked around or other stuff)?
Comment: @dmckee thanks for your reply! The PMT is quite old, and I have been using it non-stop for about 2 months, and for sure have bumped it on a table once or twice, and had once accidentally exposed it to room light without turning off the voltage.
Answer: When you expose a PMT with full light, you can seriously affect its gain. Years ago I was involved in a project where a PMT had its gain stabilized by monitoring the output due to a (dim) LED that flashed at 1 kHz. We noticed that the voltage needed to maintain constant output increased over time; when we reduced the intensity and frequency of the LED pulse, the "gain loss curve" slope decreased significantly.
The mechanism for this was believed to be electron bombardment of the dynodes - they cause changes to the surface of the dynodes, reducing the electron multiplying qualities.
The other thing that might have happened - you could have created a microcrack when you "knocked it". In that case, air enters the enclosure and this would show up as a discoloration of the PMT surface (for bialkali cathodes, it would go from light brown to clear).
The third thing that can sometimes cause gain loss (but this is usually a slower effect) is leakage current across the bulb (yes, I had to measure that to believe it). With the cathode at - 1500 V, mounted to a scintillator in a grounded enclosure, coupled with grease, we were getting fA of current through the envelope. This apparently caused ion migration (Na+ from the glass) that "poisoned" the cathode, resulting in a reduced gain. Adding a guard ring (at HV) made the problem go away.
And of course, it's possible that knocking the PMT+scintillator assembly would have knocked the scintillator off the PMT. If the light is no longer coupled efficiently, the peak will essentially disappear.
Three final ideas - HV supply is fried, or the preamp is. Or the preamp power is off... unlikely, but I thought I had to mention it.
It's hard to know which of these is your problem, but I hope it helps with your troubleshooting.
See also this earlier answer about PMT troubleshooting.
Comment: You're welcome! If you ever reach a conclusion let me know!
Comment: My HV was fried, so I replaced it again, and used a plastic proton-recoil detector to obtain the spectra from Gd-148. Having 1024 channels, the 40th channel is at 3200 KeV. Does that sound reasonable or should I still suspect my PMT?
Comment: Glad I had listed "fried HV" as an "it's possible"... I don't have a good feeling for the scaling on your system. Obviously if you increase HV, you will change the scale of your spectrum. What is appropriate depends on a LOT of things, and I am not familiar enough with your components to comment on that. Sorry.
Comment: Thanks for your detailed answer! The coupling issue I can eliminate, because the PMT and scintillator come as separates, and I manually attach them for every use using optical grease.


Circuit for turn on a led when load connected

Question: I'm searching for a circuit that turn on a led when the load is connected on its output, let's say for example a 5v power supply. I've seen few circuits that used two resistor in series with the positive supply rail, in order to make a voltage divider and drive a npn transistor, but in this way there will be a noticeable voltage drop on the load. Are there other way of detect a load?
Comment: Detecting loads or sources? Detecting an active power supply (source) is fairly easy. Detecting a load attached to a stable power supply is more complicated.
Comment: How much voltage drop across the sense resistance will be a trouble for your load??
Answer: Use a high side current sense amplifier (usually best with an instrumentation amplifier) followed by a comparator and switch.
Here is the basic idea:

simulate this circuit – Schematic created using CircuitLab
By using a current sense amplifier, the resistor sensing the current can be small (less than an ohm).
Set Vtrip such that when the load current exceeds some threshold, the comparator turns on the transistor.
Answer: If you want to avoid a resistance in the load circuit, you could use a Hall sensor like this one. Such sensors measure the magnetic field generated by the current in the wire going to the load, and usually output you a voltage proportional to that current.


Is there a way to take out a loan on your Bitcoin like how Ethereum can be used as a CDP in the MakerDAO to get DAI?

Question: I wanted to sell some BTC to pay some bills, but I also didn't want to lose out on the Bitcoin rise in the inevitable future. Ethereum has the ability to be used as a CDP ("collateralized debt position") to get the stablecoin DAI which you can cash out at coinbase, but still own the Ether you put up for the loan. As long as you pay back the loan, you can get the eth back.  Is there a method of doing this with Bitcoin?
Answer: The closest method of doing this is using an exchange that provides margin trading. The only issue I have with it is that you need to trust your BTC with the exchange. One can recreate what the makerdao has with better rates too, but with a more centralized approach.
Say you wanted to cash out $1000 USD worth of BTC (ex. 0.1 btc @ 10k btc price), but you also don't want to sell it because you see the price might be higher in the long term. What you can do is the following:

Deposit 0.2 btc ($2000) onto an exchange that provides margin.
Sell the 0.2 btc for USD. Now you have $2000 in your account.
Send $1000 to your coinbase or however you want it in and cash out to your bank account. Now you have $1000 USD in your bank.
The remaining $1000 USD that is on the exchange. Open a margin buy position for 0.2 btc.
When the price of BTC doubles from the price you sold at, you close the position. Now you have back your 0.2 BTC minus the fees.

The liquidation price of your margin position will be usually 50% of the price you sold at. Say its 10k, if you were to get liquidated, BTC would need to drop to 5K.
Bottom line, your basically taking a loan out with your BTC as long as the price doesn't drop by 50% from the current price. Also to note, not your keys not your coins risk if the exchange exit scams or freezes your account.
Answer: Maybe if more people work on things related to discreet log contracts, it is possible but I don't know any live projects that will help you achieve the same: https://medium.com/@cryptogarage/announcing-the-global-launch-of-p2p-derivatives-beta-application-7ecc02fa02a1
RGB: https://rgb-org.github.io/
Omnibolt: https://github.com/omnilaboratory/OmniBOLT-spec
Liquid: https://github.com/ElementsProject/elements
Above are some links that are interesting proposals/projects and might help solve this problem in future
I am also trying to research more about discreet log contracts


How to check whether the activity I am starting is the activity which is running?

Question: I have 6 Buttons, for 1st 3 Buttons I want to start same activity and for other 3 Buttons separate new activities.
So problem arises when i click on 1st button and then the second Button which starts same activity because we can not start same activity from same activity.
So I just need to know weather the activity which i am going to start is the same activity which is running, based on that if same activity then I'll just update some UI contents else start new activity.
So anyone can help me to know this?
Answer: Here's a good way to do it using the activity manager.
You basically get the runningTasks from the activity manager. It will always return the currently active task first. From there you can get the topActivity.
Example here
There's an easy way of getting a list of running tasks from the ActivityManager service.
You can request a maximum number of tasks running on the phone, and by default, the currently active task is returned first.
Once you have that you can get a ComponentName object by requesting the topActivity from your list.
Here's an example.
ActivityManager am = (ActivityManager) this.getSystemService(ACTIVITY_SERVICE);

     // get the info from the currently running task
     List< ActivityManager.RunningTaskInfo > taskInfo = am.getRunningTasks(1);

     Log.d("topActivity", "CURRENT Activity ::"
             + taskInfo.get(0).topActivity.getClassName());

     ComponentName componentInfo = taskInfo.get(0).topActivity;
   componentInfo.getPackageName();

You will need the following permission on your manifest:
uses-permission android:name="android.permission.GET_TASKS"

Comment: all activities runs on same task and same application and all are in my application
Answer: You can check activity's class, for example (suppose 'this' is current activity):
if (this instanceof ActivityClassYouGoingToStart) {
    // update UI
} else {
    // start new activity
}


Rhetorical questions in argument

Question: The author in this model essay never answers or presents counterarguments to his many rhetorical questions. So why would the author choose to conclude a paragraph and write this essay in the form of questions? By allowing, inviting, and 'opening up' to counterarguments, counterclaims, and rebuttals, don't questions weaken or worsen an argumentative essay?
Answer: In asking a question in this manner, the author uses (or tries to use!) rhetorical questions. The author does not expect a response - indeed, such a response is not possible, because the responder has way to insert himself or herself into the piece. These questions are not meant for "allowing, inviting, and 'opening up' to counterarguments." It appears the author's intent is to ask questions that (to the author) have obvious answers in a way to engage the reader more.
Rather than looking at an artificial, bad example, it would be more helpful to look at a canonical good example: the speech given by the Corcyrean Envoy at Sparta prior as told by Thucydides. In the opening of the speech, the envoy effectively makes use of several rhetorical questions.
Answer: In the piece you're referring to, I see four questions. The two in the first paragraph aren't rhetorical questions. The second question there is a clarification of the first, and the first is setting up an ostensibly stronger claim than the claim to be proved, on the idea that if you prove the stronger claim, you thereby prove the weaker claim as well. It's not a rhetorical question because the writer proceeds to attempt to answer the question. Similarly with the question in the third paragraph: the writer raises this question as a possible objection to the argument he's presenting, and proceeds to answer the question to rebut that possible objection. The question at the end of the second paragraph is the only rhetorical question in the piece. Rhetorical questions are questions that are not intended to be answered (and that the writer doesn't proceed to try to answer). They pose a question with a seemingly obvious answer in order to use that implied answer as a step in their argument. They can be effective argumentative tactics in persuasive writing in general, but I always discouraged them when teaching philosophical writing because the gold-standard of clarity in an argument is having all the premises of an argument stated explicitly. Dan Dennett advises to always try answering rhetorical questions (similar to his advice to always have a "ding" go off in your mind when you come across the words "of course," "obviously," etc. in an argument), to guard against arguments sneaking in unquestioned assumptions.

Rhetorical questions in argument


iPhone see apps downloaded from different Apple ID

Question: On iOS 12 iPhone is there a way to see a list of apps downloaded from a different Apple ID (the one I'm not currently signed-in to). I would like to get all apps on one account so I don't have to input passwords for several different Apple ID's.
Answer: No, in general, that would abuse the privacy of the other account.
The only exception is if all Apple ID were in family sharing and opted in to share app information. Then you can browse the other purchases from your account.
There also isn't a way on device to see which account purchased which apps if you happen to sequence several accounts to purchase on one device.


How is Maximum Take Off Weight determined?

Question: How would a test pilot determine the MTOW of an aircraft. Does the manufacturer predict this value?
Comment: how about asking for "flight tests that result in updating the MTOW" or "flight tests that are conducted to determine the MTOW". The test pilot does not determine the MTOW limitation himself/herself, they do what the test procedure asks for.
Comment: Just as a matter of information, determining the MTOW can involve things you might not normally think, especially on some aircraft. For example, the MTOW of some B747-400BCFs depends in part on both the fuel density and the CG. If the fuel density is 6.43 to 7.1 lbs/gal, you're allowed the full 870000 lbs (assuming an adequate runway of course). If the density is 6.0, the MTOW is 820000. Between 6.0 and 6.43, it varies depending on the CG. Those numbers are from section 1-05-001 of http://terryliittschwager.com/WB/manuals/747-400BCF_GPR1_WBM10.pdf.
Answer: Pilots do not determine the official MTOW of an aircraft. MTOW will be estimated by the manufacturer during the design of the aircraft based on the required payload of the aircraft and the design configuration. It will be adjusted based on the detail design of the aircraft to comply with regulation requirements.

§25.1533   Additional operating limitations.
(a) Additional operating limitations must be established as follows:
(1) The maximum takeoff weights must be established as the weights at
  which compliance is shown with the applicable provisions of this part
  (including the takeoff climb provisions of §25.121(a) through (c), for
  altitudes and ambient temperatures).

MTOW affects many other aspects of an aircraft's performance. It will affect stopping distance after a rejected takeoff, takeoff performance (including engine failure), climb performance, taxi weights, and many structural aspects. MTOW will be chosen so that the requirements for all of these conditions are met. This is why new engines or winglets which improve performance will allow a higher MTOW.
Of course, as always, the pilot has the authority to set their own personal MTOW more conservatively, if they feel it is necessary for safer operation of the aircraft.
Answer: MTOW is defined and then verified by the manufacturer.
During "verification", tests and other analyses are conducted to show compliance to all MTOW related requirements. For example, landing gear analyses and tests are conducted for their corresponding FAR23 or FAR25 regulations. Flight Loads analyses/tests are also conducted, so that the structure can withstand all foreseeable loads during the entire operational life of the aircraft.
During the development of the aircraft, the MTOW can be updated (which is painful and costly) and during flight tests, final tuning can be required. Inceasing MTOW is more costly, in terms of development efforts and re-engineering of the aircraft. Decreasing MTOW would probably limit the operational capacity of the aircraft(less fuel, or less payload).


What does it mean to say that the operators evolve in time in the Heisenberg picture?

Question: I get that in the Schrödinger picture the wave function evolve in time and the quantum operators are independent of time. However, in the Heisenberg picture the operators evolve in time and the wave functions remain independent. I understand that the operator must obey the commutator equation but, what does it mean to have an operator that evolve in time from a physicist's point of view?
Answer: So in my view the Heisenberg picture is just one of the many "interaction pictures" that exists and the fundamental idea is just that we are doing a sort of quantum coordinate transform where we describe our Hamiltonian as $\hat H(t) = \hbar (\eta(t) + \xi(t))$ where in the usual case $\eta$ is the "simple" parts of the Hamiltonian and the $\xi$ is the "complicated" part having to do with interactions and what-not.
Mathematical background
So the idea is that just as $\hat H$ induces a unitary operator $$U(t) = \mathcal T \exp\left(-\frac{i}{\hbar} \int_{t_0}^t \mathrm d\tau~\hat H(\tau)\right)$$we can say that $\eta$ induces a unitary operator $$u(t) = \mathcal T \exp\left(-i \int_{t_0}^t \mathrm d\tau~ \eta(\tau)\right)$$and all predicted expectation values $$\langle A \rangle_\Psi = \langle \Psi_0 |U^\dagger \hat A U|\Psi_0\rangle$$can have $uu^\dagger = 1$ inserted into them arbitrarily to yield $$\langle A \rangle_\Psi = \langle \tilde \Psi| \tilde A | \tilde \Psi\rangle, \text{ where }\\
|\tilde \Psi\rangle = u^\dagger U |\Psi_0\rangle \text{ and }\tilde A = u^\dagger\hat A u.$$
One can then confirm that $$\frac{\mathrm d\phantom{t}}{\mathrm dt} |\tilde \Psi\rangle = u^\dagger \left(i\eta -\frac{iH}{\hbar}\right) U ~|\Psi_0\rangle = - i \tilde \xi ~|\tilde \Psi\rangle,\\
\frac{\mathrm d\tilde A}{\mathrm dt} = u^\dagger \left(i \eta \hat A + \dot A - i \hat A \eta\right) u = i[\tilde\eta, \tilde A] + \widetilde{\dot A}.
 $$
So these are all expressed in the tilde-basis and my interpretation of this is just that you have changed coordinates into a reference frame which is varying over time.
Actually I go maybe a step further than this generic math suggests. So if you ever deal with a bosonic annihilator $b$ you will be introduced to its quadratures $x = (b^\dagger + b)/2$ and $p = i(b^\dagger - b)/2$, and the coherent states $b|\alpha\rangle = \alpha |\alpha\rangle.$ Under these the harmonic oscillator Hamiltonian $H = \hbar \Omega~ (b^\dagger b + 1/2)$ actually just induces a time evolution $|\alpha\rangle \mapsto |e^{-i\Omega t} \alpha\rangle$ in the Schrödinger picture, and one can work out that taking $\eta = \Omega b^\dagger b$ makes this really obvious because you have $b \mapsto e^{-i\Omega t} b$ so of course that's what it does. Meanwhile $\langle x\rangle$ and $\langle p \rangle$ describe $|\alpha\rangle$ as being centered on a specific point in phase space given by the real and imaginary parts of $\alpha$.
What I am inclined to do here is to imagine that I can always create this sort of coherent-state phase space so that the Hamiltonian here can be visualized as a flow field depicting where the probability flows given where it was, and in this case it is a big flow field going around the origin in circles. What this interaction picture did was, it used rotating coordinates for phase space $\tilde x(t) = x \cos(\Omega t) + p \sin(\Omega t), \tilde p(t) = p \cos(\Omega t) - x \sin(\Omega t),$ and thus that rotating part of the flow map disappeared; we offloaded all of that onto the operators (in this case $b, b^\dagger$).
The Heisenberg picture in particular
Once you have this general recipe for the interaction picture, it is very tempting to take the special case where $\eta = \hat H/\hbar$ and thus $\xi = 0$, in which case $u = U$ and $|\tilde\Psi\rangle = |\Psi_0\rangle.$ From a physical perspective this then means that this coordinate transformation zeroes out the flow field so that the state never evolves across phase space, rather what evolves is how we measure these various quadratures of our system.
So like I imagine just watching a classical bouncy ball describing several perfect parabolas as it loses no energy bouncing on a perfectly flat frictionless floor, this coordinate transform physically means using a camera which is totally fixed on the ball, and in this system the force of gravity on the ball disappears altogether, the floor moves off to the side at a pretty constant speed and flies up to meet the ball, and we introduce a fictitious force which exactly balances out the floor-force on the ball whenever the floor is in contact with the ball. We are co-moving with the ball and we describe the entire world around the ball as changing instead of the ball, and so things like "what is the dynamical height of the ball?" become questions like "what is the dynamical distance of the floor from the ball?" which must ultimately be solved by similar equations, transferred to the floor.
An interaction picture is some sort of hybrid visualization, for example just using free-fall coordinates to zero out the effect of gravity, but not zeroing out the forces of the floor. Meanwhile, the floor experiences a constant acceleration upwards, due to that transformation. So the ball starts off going upwards at speed $0$ and then after one impact it starts traveling upwards at speed $v$ and then after another impact it starts traveling upwards at speed $2v$ and then $3v$ and so on, the ball has these long constant-speed trajectories interrupted by the floor which each time I think gives it a constant dose of momentum upwards.


My microphone is not working

Question: My alsa info: http://www.alsa-project.org/db/?f=f940e25a16fa01f2a1c2f980562b2a97d4b97ee5
My k56cd asus laptop has a combo jack (both headphones and mic) so when i plug in my headphones (Razer Kraken pro neon which have only 1 jack) only the headphones work, the mic does not.
Answer:
Install "Jack retasking for HDA Intel sound cards" with:
sudo apt install alsa-tools-gui

Open it with ⊞ Win or in terminal:
hdajackretask

Select the up-right checkbox "Show unconnected pins"

In the not connected pins 0x18 and 0x19, select "override", and select "microphone".
If, they don't have the microphone option, do this in 0x16 or 0x12

Click "apply now" (bottom right) and "install boot override".

install pavucontrol
sudo apt install pavucontrol

Open pavucontrol, go to Input devices (4th menu) and select "Microphone", instead of "Internal microphone" (if it appears "(unplugged)" see if the volume indicator moves while you speak, otherwise restart - it can still be "unplugged" but should work).

For dual-boot systems, turn off the machine after the last windows use.
Comment: used for Asus Vivobook and Ubuntu 22.04 and it worked
Answer: The problem could be that the input devices are not set up correctly. You should try PulseAudio Volume Control to correctly set it up.
sudo apt-get install pavucontrol

Open it up:
pavucontrol

Go into the Input Devices tab and underneath your audio card select the correct mic from the drop down list.
However, if your issue occurs when you reboot with the jack still plugged in, it can sometimes be resolved by simply unplugging and plugging the jack back in once the computer fully starts back up.
Answer: You could verify also with alsamixer. Open the terminal and type alsamixer and then look for the microphone settings in alsamixer.

My microphone is not working


Openshot Video Editor shuts down my system while exporting a project to HDYoutube (Ubuntu 11.10)

Question: As you read
I'm having untimely difficulties with "OPENSHOT".
I do a lot of editing for youtube and it requires HD uploading.Now the problem here seems rather odd and I know of a few people who are suffering from the same issue.
This problem began when I installed the Ubuntu 11.10 update.
I went into the video editor and began my project.
After finishing I moved to export and set the same HD export setting.
Profile: WEB
Target: Youtube-HD
Video Profile: HD 720p 25fps
Quality: Med or High (both have the same output)
-I'm not sure if thats the exact way how to export into youtube-hd, but that's irrelevant 'maybe'.-
I begin the export.
Here's the kicker... after 5 minutes and almost half way through the export, the entire system "shuts off".
It takes a few minutes to restart it, attempting restart to early makes it shut down again... (I have to wait a good 3 or 4 minutes. Thankfully I saved my projects)
I'd appreciate some help on this, and excuse me for my "wrong ways of posting" i'm a noob, so try being a little patient ^_^
(If this problem can't be solved in the next few hours, I'll be late on my next upload and most likely loose my job for youtube...)
Comment: someone please help :(
Comment: I have the same problem, the computer shutting down as if I using the UI to turn it off. I used with mp4 format and libx264 codec. When I tried both with full hd, ad simple HD resolution both the the result file was 4,3 GB. My laptop not was normal than usual.
Answer: You need to provide more info.  Does the system instantly power off, or does it shutdown as if you used the UI to shut it down?
You said, "attempting restart to[o] early makes it shut down again," so I'm going to hazard a guess that your system is overheating.  See if running another app that pegs your CPU at 100% for that period of time causes the same behavior.
You probably just need to clean the dust out of the system to restore airflow.


Tar incremental backups - skip restoring deleted files

Question: To restore an incremental backup we need to first restore the full backup then the incrementals in the same order then deleted files are removed. It is useless to restore files then delete them and that is a waste of time with big files. Is there a way to avoid that using tar?
Comment: It does. I use it. Check the docs.
Comment: Gnu tar supports incremental backup. I am using switch `-g` for years, and have successfuly restored files from such backups. I have never encountered unreliability you are writing about? This is new for me.
Comment: `tar` does not support incremental backups, could you be a bit more specific?
Comment: You must be mistaken, the official `tar` man page http://schillix.sourceforge.net/man/man1/tar.1.html does not mention incremental backups at all. You must be referring to something else. Which program do you have in mind?
Comment: Check [GNU tar docs](https://www.gnu.org/software/tar/manual/tar.html#SEC96) section 5.2. I'm using `tar (GNU tar) 1.30` and the option is there when issuing `tar --help`
Comment: This is a different program. GNU tar claims to support incremental backups since 1992, but fails to restore the incrementals in case that the differences are not trivial. I cannot recommend making backups with this program as it is too unreliable.  I guess you like the guarantee that any backup will always restore correctly. You may like to search this portal for `gnu tar incremental backup` for detailled problem discussions.
Answer: If you like to skip some of the files from being extracted, you would need to know their names before they would be extracted.
This would require you to completely read all tapes in advance to analyze the content. In other words: the time to restore would double. Given that today, the restore of the backups for a typical filesystem takes more than a day, this does not seem to be a useful alternative.
If you know on Monday, which files will be deleted on Tuesday, backups could be more efficient, but a backup from Monday only has the knowledge from Monday.
A backup is only as efficient as it's meta data set and GNU tar stores very few meta data. GNU tar only knows the names of all files from archived directories.
A typical backup utility stores a lot more meta data than GNU tar. An important information that is missing from the GNU tar archives is the list of inode numbers for all files. If you have inode numbers in the backup, you can track file renames. GNU tar cannot track renames due to the lack of meta data.
If you have a backup program that stores sufficient meta data, the state of the art method to restore incremental backups is the following:

start with an empty target filesystem

extract the initial full dump to the target filesystem and keep a data base that remembers which files are directories and which files are non-directories as well as the original inode number from the backed up filesystem and the new inode number used on the filesystem where the restore takes place.

extract the incremental follow up backups in the order they have been created.

with every file and directory in the current incremental that is restored, check it's inode number in the data base for the related new inode number. If there is no new inode number in the data base, this is a new file, if there is already a new inode number in the data base, and the current file name differs, rename the file to the current name.

if a directory and it's content is extracted from an incremental archive and a file/directory is no longer in the new state of that directory rename all these files/directories that curently are on the target filesystem but not on the directory just processed to a temporary directory and remember the temporary name.

If the current incremenal has been completely restored and there are remaining files in the directory with the temporarily renamed files, these files are files that have been removed in the original filesystem and thus need to be removed on the new target filesystem.

You always may need to be able to store more data in the new target filesystem than in the source for that reason. Because of the few meta data in the GNU tar backups, there is a tendency that GNU tar needs more space for the incremental backups and more additional space in the target filesystem than solutions that store more meta data.
Comment: It is obvious that the downvoting trolls have no clue. Otherwise, they would be able to write a useful cmment...
Comment: You are mistaken. I am not the author of the original `tar` implementation and I do not have te arrogance to call my tar implementation `tar`.


How to find residuals and plot them

Question: I have been given data
x = c(21,34,6,47,10,49,23,32,12,16,29,49,28,8,57,9,31,10,21,26,31,52,21,8,18,5,18,26,27,26,32,2,59,58,19,14,16,9,23,28,34,70,69,54,39,9,21,54,26)
y = c(47,76,33,78,62,78,33,64,83,67,61,85,46,53,55,71,59,41,82,56,39,89,31,43,29,55,
     81,82,82,85,59,74,80,88,29,58,71,60,86,91,72,89,80,84,54,71,75,84,79)

How can I obtain the residuals and plot them versus $x$? And how can I test if the residuals appear to be approximately normal?
I'm not sure if I do the original linear fit correctly as I got the equation $y=6.9x-5.5$ but the lecture notes says that the linear regression line should be of the form $y_i=\beta_0+\beta_1x+\epsilon$.
Comment: The equation you got *is* of the form mentioned in your notes, with $\hat{\beta_0} = -5.5$ and $\hat{\beta_1} = 6.9$. The residuals are just $r_i = y_y-\hat{y}_i = y_i - (-5.5 + 6.9 x_i)$
Comment: Which package are you using? For example Matlab's 'regress' function returns the residuals as an output and you can graph using a histogram
Comment: I'm using Sagemath. I can also use R via it but I have very little experience of it.
Comment: Concerning the 2 equations that you have up there. If the regression line (as a linear function) is of the form $y = a +k x$ then the linear model is $E[Y|X] = a+ k X$ and using error terms this is $Y = a + k X + \epsilon$ where $\epsilon$ is an error term with zero expectation. This is the sense in which the two equations fit together.
Answer: EDIT: You have an R tag but then in a comment say you don't know much about it. This is R code. I know nothing about Sage. End edit
You can do this
x = c(21,34,6,47,10,49,23,32,12,16,29,49,28,8,57,9,31,10,21,
      26,31,52,21,8,18,5,18,26,27,26,32,2,59,58,19,14,16,9,23,
      28,34,70,69,54,39,9,21,54,26)
y = c(47,76,33,78,62,78,33,64,83,67,61,85,46,53,55,71,59,41,82,
      56,39,89,31,43,29,55, 81,82,82,85,59,74,80,88,29,58,71,60,
      86,91,72,89,80,84,54,71,75,84,79)

m1 <- lm(y~x)  #Create a linear model
resid(m1) #List of residuals
plot(density(resid(m1))) #A density plot
qqnorm(resid(m1)) # A quantile normal plot - good for checking normality
qqline(resid(m1))

Comment: Okay. So I saw the picture with caption density.default(x=resid(m1)). Should this code output two graphs? And should I check from the graph is the residuals appear to be approximately normal?
Comment: The code will output two graphs - one is a density plot (does it look bell shaped?) the other is a quantile plot; if the residuals were perfectly normal, the points would all lie on the straight line.
Comment: Right. Code works if you change last lines to plot(qqnorm(resid(m1))) and plot(qqline(resid(m1))). So I think residuals does not satisfy the normal distribution as there are point farther below the line than over the line. Are there any numerical criterion to check the normality?

How to find residuals and plot them


How do I open a copied project in Visual Studio?

Question: I have copied a whole project onto my PC, both into My Documents/Visual Studio and into inetpub/wwwroot, but when I try to open the project in Visual Studio, it tries to open just 1 file .vssproj and gives me error messages, like : "The project file cannot be loaded. The application for project ... is not installed.". What am I doing wrong?
Comment: "The project file cannot be loaded. The application for project ... is not installed."
Comment: Yes, I have considered marking it as answered. However, although I gave points for the below answers, nevertheless they are not really what I need.
Answer: If VS 2005 has not been upgraded to Service Pack 1 then a web application project (rather than a website) will give this error.
Answer: As others have said, without knowing a specific error it's hard to help. However, the sln and csproj files are just text files, you can always just open them up in notepad and do a search and replace on any obvious path problems. It's often quicker than creating a new project and adding all the files / references.
Comment: "The project file cannot be loaded.
The application for project...is not installed.
"
Answer: I had this same exact error when double-clicking on the file as opposed to going to VS and using its menu to open it. It seems a problem with file associations.
Answer: Without telling the specific error you're getting it's hard to help, but I'm guessing the file paths in the project file are incorrect. Try creating a new project and manually adding the files and see if you get the same errors.
Comment: "The project file cannot be loaded.
The application for project...is not installed.
"
Answer: Without the specific error messages, it's tough to be sure, but if you have an entire solution from your source machine rather than just a single project, you may want to try copying that over instead.
Comment: "The project file cannot be loaded.
The application for project...is not installed.
"


What community activities do monks in southest asia take part in?

Question: I often read about monks have little free time in their schedules but aside from teaching other monks I am not sure what they do with all their time. I have seen monks in Tibet working in an orphanage and monks in Thailand giving public talks.
Aside from this what involvement with the community do monks have (excluding dana)?
Comment: Perhaps you want to generalize your question to cover all monks and not just southeast asian monks
Answer: They try to fulfill   "Muni vrutha" - Muni's=Saga's, vrutha=Duty.
refer - Nalaka sutta.
[Nalaka:]  I ask you, Gotama, you who have gone to the beyond of all things. I'm intent on the homeless life; I long for the almsround. Tell me sage, when I ask you, the utmost state of sagacity.
[The Buddha:]
I'll explain to you a sagacity hard to do, hard to endure.
Come now, I'll tell you.
Be steadfast. Be firm.
Practice even-mindedness, for in a village there's praise & abuse.
Ward off any flaw in the heart. Go about calmed & not haughty.
High & low things will come up like fire-flames in a forest.
Women seduce a sage. May they not seduce you.
Abstaining from sexual intercourse,……..
Comment: Know from the rivers in clefts & in crevices: those in small channels flow noisily, the great flow silent. Whatever's not full makes noise. Whatever is full is quiet.   The fool is like a half-empty pot; one who is wise, a full lake. A contemplative who speaks a great deal endowed with meaning: knowing, he teaches the Dhamma, knowing, he speaks a great deal. But he who, knowing, is restrained, knowing, doesn't speak a great deal: he is a sage worthy of sagehood; he is a sage, his sagehood attained.
Answer: Householder Hugh, interested
the Duties of the monks who are the disciples of the Buddha, and follow his Dhamma-Vinaya faithfull, in what ever country, past, present and in the future, are equal.
Aside of practicing (meditation or involving in discussions, learning, repeating the Dhamma), carry the heritage proper and strive for being worthy for gifts by going after paths, fruits and highest liberation, Bhikkhus have serial duties in regard of their community of monks and teacher, student relations within there. Outside of this, there are NO duties at all, neither teach Dhamma nor others toward lay people and society. (if doing such, for the most, especially if social engaged, it's not seldom related with wrong livelihood and corrupting families, grave wrong doings) When good monks are teaching, then such is always an act of compassion, not even allowed to receive alms in return.
A set of duties of Bhikkhus generally in their community can be found here:
Vatta Khandhaka: Collection of Duties
There are further duties, like to take part on community transactions and the two weekly citing of the Patimokkha, their main rules.
There are countless other duties, related to their requisits, their rules and practice, and to learn all of them, one of the first, starting with ordination.
Lay-people, following the Tripple Gems, are open to give what ever inspired into the great field of merits, the heritage carries of the Bhikkhu Sangha, by their lovable deeds, by lovable words, by lovable thoughts, by keeping open house to them, by supplying their material needs. If they are after much success and eager to stay close in practice and refuge, there are duties given by the Buddha as success for such.
Monks are excpected to stay (SN 16.3: Candūpama Sutta —) Comparable to the Moon at the two times in touch with laypeople, and if not able not getting engaged in any business outside their internal duties, should not leave their community and training.
In fulfillment of ones duties, the Buddha-Parisata (assembly of Sangha and lay follower) do not only to the best for their own, but work also for next generations, that this steam of goodness, deriving from the Buddha, will for many being happiness and as a way beyond, stay long time alive and accessible in this world. May nobody misses to take such seldom gained touch as a precious possibility joining and take part, where ever one is.
(Note: this is not given for trade, exchange, stacks or entertainment, but only as means to escape this binding wheel)


Independent variable correlated with dependent variable

Question: We are doing a regression to predict APR for auto loans.  Among other independent variables, can I use Dealer mark-up?  The issue is that Dealer mark-up is a part of APR: Dealer Mark-up = APR-Note Rate.
Answer: Rearranging your equation so that the response variable is on the left-hand-side you get:
$$\text{APR} = \text{Dealer Markup} + \text{Note Rate}.$$
If Dealer_Markup is a known explanatory variable in your model then the regression is essentially just a regression for the Note_Rate.  The former variable serves only as a fixed "offset" variable in the regression model.  Given a set of explanatory variables that can be used as predictors of the latter, you could model this using either of the following equivalent models in R:

Model 1: APR ~ offset(Dealer_Markup) + Explanatory_Var1 + ... + Explanatory_Varm
Model 2: Note_Rate ~ Explanatory_Var1 + ... + Explanatory_Varm

In the first model we directly model APR and we use Dealer_Markup as an offset variable in the regression, so that its value enters the model with a fixed coefficient of one.  In the second model we ignore  APR and Dealer_Markup and go straight to modelling the Note_Rate.  In both cases the models will give the same outputs for the estimated coefficients on the explanatory variables, and will have the same goodness-of-fit statistics.
As you can see, using Dealer_Markup in a regression of APR is essentially equivalent to working directly with a regression on Note_Rate.

What is the purpose of your model? As a broader level, if you want to know if this is a sensible model you need to take a step back and as yourself the purpose of your regression.
If the purpose is predictive (i.e., you want to predict APR from other variables) then you should consider what information you have available at the time of prediction, and in particular, whether you have knowledge of Dealer_Markup in that prediction problem.
If the purpose of the model to to make causal inferences then things get a little trickier.  In this case you must be aware of the possible presence of confounding variables and collider variables.  The Dealer_Markup could be a collider variable in this case, and you should have a deeper think about the plausible causal structure of your problem, and the goal of the regression.
Answer: Shouldn't be a problem. If you don't have anything else in the model your regression coefficient would just be 1 (assuming that formula in your question is the whole formula for Mark-up)
In general with regression, you should believe your dependent variable is correlated in some way with your independent variable(s). Those correlations don't necessarily have to be linear, but there should be some relationship there. Otherwise your regression model won't be any good!


Where the gradient of a convex function approaches zero

Question: Does there exists a differentiable convex  function $f: \mathbb{R}^n \rightarrow \mathbb{R}$ with a unique global minimum which we denote by $x^*$ such that there exists a sequence $x_k$, not converging to $x^*$, such that $||f'(x_k)|| \rightarrow 0$?
Answer: No. Let's normalize the function so that $u^*=0$ and $f(0)=0$.  I claim that for every $r>0$ the infimum $\inf_{|x|> r}\| f'\|$ is positive; this obviously precludes the scenario described in your post.
Let $m=\min_{|x|=r} f(x)$; this is a positive number because $f$ attains its minimum on the sphere, and the minimum is not zero. Given $x$ with $|x|>r$, consider the one-variable function $\varphi(t)=f(tx/|x|)$. Clearly, $\varphi$ is  convex, $\varphi(0)=0$ and $\varphi(r)\ge m$. By the mean value theorem, $\varphi'(\xi)\ge m/r$ for some $\xi\in (0,r)$. Since $\varphi'$ is increasing, it follows that $\varphi'(|x|)\ge m/r$. Thus $||f'(x)||\ge m/r$, proving the claim.


Is a child born to a Jewish father and non-Jewish mother, considered a non-Jew in the same regard as a child born to two non-Jewish parents?

Question: I thought to myself it must be, in general, considered differently in Judaism, but I haven't found written sources for that yet. Is the first considered differently in the Torah than the second?
Comment: Some people use the term "Zera Yisroel" (Seed of Israel) when referring to someone with a Jewish father and non-Jewish mother. This person is traditionally not considered Jewish, although some authorities do encourage such a person to convert. I believe there are some questions about this term and situation elsewhere on this site.
Answer: Judaism is a very law based religion, and just like any society based on laws there are subdivisions that can add context. A child born of a religiously Jewish father and non Jewish mother is not considered Jewish. This is the law on the books for normative Jewish law.
Having said that, there are some subtleties to the situation which have practical ramifications. In many Middle Eastern Jewish communities for example, if there was a Jewish man from the community who married a non Jewish woman the relationship was not initially accepted by the community. However, if the man continued to attend services, and his wife showed devotion to Judaism within the community, then the community would make conversion for her much easier if she was to become pregnant. Because there is an idea that we want to keep the seed of Israel ongoing.
This "seed of Israel" concept has been officially coined for situations in which a child is born to a Jewish father and non Jewish mother. Certain Rabbis have argued in the past that conversions for these children should be made easier, especially if these children are raised practicing Judaism. I will now quote an answer from another question that applies here and provide a link at the end:

Rabbi Tzvi Hirsch Kalischer was the first to coin the phrase: Zera
Yisrael
Rabbi Kalischer used this in reference to someone born to a non-Jewish
mother but had a jewish father. He referred to them as Zera Kadosh -
Holy Lineage. However, Rabbi Kalischer did not use it in a halachic
context.
The most vocal and bold Halachist to apply this concept was the Former
Sephardic Chief Rabbi of the State of Israel Rav Ben Zion Meir Chai
Uziel (שו"ת משפטי עוזיאל, כרך ב יו"ד סי' נב) who argued that the
concept of Zera Yisrael is considered so legitimate that it can be
applied to determine lineage. For example, if the non Jew -zera
Yisrael father is a Kohen, despite his mother being a gentile, once he
converts his "zera Yisrael" kicks in and he is considered a full
fledged Kohen and can partake in the many benefits/ prohibitions that
apply to Kohanim.
Rabbi Uziel was deeply concerned about the fate of children born to a Jewish father and a non-Jewish mother. Such children, although of
Jewish stock (zera Yisrael), are in fact not halakhically Jewish.
Children raised in such intermarriages will be lost to the Jewish
people entirely. Thus, it is obligatory for rabbis to convert the
non-Jewish mother in order to keep the children in the Jewish fold.
Rabbi Uziel noted: "And I fear that if we push them [the children]
away completely by not accepting their parents for conversion, we
shall be brought to judgment and they shall say to us: 'You did not
bring back those who were driven away, and those who were lost you did
not seek.' (Yehezkel 34:4)."
Some (source for quote above as well) have argued that the concept of
Zera Yisrael is also used as a justification to streamline the
conversion process. Where traditionally a certain amount of time is
given in order to bring the prospective convert up to speed in torah
knowledge, or acclimation to an observance life, as well as to discern
their true motivation for conversion. Some have argued that in the
case of a Zera yisrael, we speed up the process and accept them right
away as it is a mitzvah to bring that back under The Wings of the
Schechina.
However, this concept (if legitimate) is only limited to those that
are literal descendants of Jewish lineage.

Source: https://judaism.stackexchange.com/a/73864/9045
Answer: Great question! Given that your question has orthodox tagged in, I assume you want an approach of Jewish law. In Judaism, matrilineal descent can be the only defining factor of a persons Jewish status (unless geirus), regardless of whether the father is an "observant" Jew or not, the children can never be Jewish unless they convert and until then they do, they are completely as non-Jews as a person born to 2 non-Jewish parents.  Matrilineal descent is evidenced by when Ezra returned back from exile he returned and saw many of the Jewish men taking non-Jewish wives, he then cried out and as the verse states:

"Now then, let us make a covenant with our G‑d to expel all these
women and those who have been born to them, in accordance with the
bidding of the Lord and of all who are concerned over the commandment
of our G‑d, and let the Torah be obeyed." aka those that are born to
non-Jewish women are expelled from being considered Jewish.

The second and most compelling explanation is found:

You shall not intermarry with them; you shall not give your daughter
to his son, and you shall not take his daughter for your son. For he
will turn away your son from following Me, and they will worship the
gods of others, and the wrath of G‑d will be kindled against you, and
He will quickly destroy you.- Deuteronomy 7:4

Whilst all marriages between Jews and a non-Jew is forbidden and not considered a marriage this special mention of marrying non-Jewish women turning away your son from following G-d means that they are not considered Jewish once they are born to a non-Jewish woman.
In terms of conversion, it is much easier to convert and exposure to Judaism helps inform the beis din that you are serious and know what you are talking about.
I hope I helped and feel free to ask more questions.
Please read this for further reading:
https://www.chabad.org/library/article_cdo/aid/601092/jewish/Why-Is-Jewishness-Matrilineal.htm
Answer: It depends on a number of factors, in Orthodox Judaism yes you would be considered fully non-Jewish. However they'll often give you an easier time if you want to convert.
In Reform Judaism if you were raised Jewish with either of your parents being Jewish than they consider you a Jew.
In Conservative Judaism it's a more complex question that depends on the community.