Gauss law ambiguity

Question: When we use Gauss theorem/ gauss law....how do you decide what shape the Gaussian surface chosen must be for a given charge distribution(finite charge distribution)....because for a given charge distribution,I can draw a sphere , a cylinder , a cube and similarly any Gaussian surface enclosing the charge completely...but all of them would give different values of electric field right at the same given point.please explain how the same universal law giving different expressions of electric field at the same point due to a finite charge distribution makes any sense...because irrespective of shape considered,the same net charge is enclosed
Comment: If Gauss's law is applied correctly any chosen surface will give the correct value for the electric flux through the chosen surface. Please give an example where Gauss's law "does not work".
Comment: Gauss's Law applies to every surface that encloses a charge.  However, if you want to be able to evaluate the integral, you should choose the Gaussian surface such that the electric field strength is constant over the entire surface.  Once this is done, the integral usually simplifies to a known formula.
Answer: Let me state Gauss law very briefly:
The surface integral of electric field over a closed surface is equal to the charge contained within the surface over $\epsilon_0$.
$$ \int_{\Delta s}{\mathbf{E\cdot ds}} = \frac{q_{en}}{\epsilon_0} $$
$$or$$
The divergence of Electric field at a point of space is equal to the charge density at that point over $\epsilon_0$.
$$\nabla\cdot\mathbf{E} = \frac{\rho}{\epsilon_0}$$
Unlike Coulomb's law, which directly gives an expression for the electric field, Gauss law gives a differential equation of vectors to solve the electric field from. In short, electric field is difficult to calculate from Gauss law in most circumstances.
But we still can find the electric field if we somehow solve the integral. This is practical when there exists symmetry in the situation where we want to calculate electric field.
So,

for a given charge distribution,I can draw a sphere , a cylinder , a cube and similarly any Gaussian surface enclosing the charge completely...

If you take an arbitrary gaussian surface, chances are that it is not very symmetrical and you are not able to calculate the integral on the left side of the equation. Once you know the electric field, and you now calculate the integral, you'll see that Gauss law holds.
So, although you have an infinite number of choices of surfaces to verify Gauss law, you don't have as many to find the electric field from.

but all of them would give different values of electric field right at the same given point.

Let me stress again that this simply isn't true. If you are able to find the electric field from one of the surfaces, and you plug that value value of electric field in Gauss law for any arbitrary surface, then you will always find that Gauss law holds good.
Take home message: You may take a closed surface of any shape as a gaussian surface and apply Gauss law, and there will be no inconsistency.
Hope it makes sense. :)
Comment: I understand what you mean but I have also seen a formula evaluated directly from gauss law which is
Comment: Can you send me the formula? Or a link if you saw it online...
Comment: I understand what you mean but I have also seen a formula evaluated directly from gauss law which is E=q/(e0*S).....where q is charge enclosed by Gaussian surface ,e0 is epsilon 0 and S is surface area of Gaussian surface.....if u observe this equation, it is derived directly from gauss law by evaluating the lhs integral and taking integral ds as S......now here...based on whether I consider a cube,sphere,cylinder etc.....the S will change and thereby won't I get a different field at the same point for the same charge enclosed?!i hope you understood my question
Comment: Good question. But notice that as @FGSUZ said in his answer, the integral $\int \vec E \cdot \vec {ds} $ can be reduced to $E\times S$ only when E has the same value at all points of the surface and is perpendicular to it at all points. Taking an arbitrary surface will NOT change the flux, but then the integral will not be reducable to such simple forms, and we won't get a direct expression for E. In short, $E=\frac {q}{S \times \epsilon_0}$ is not correct for any arbitrary surface. Hence no contradiction arises.
Answer: @Shreyansh Darshan already gave a nice answer. Just in case, I'll highlight some points (I hope it's useful).
The Gauss law does not actually talk about the electric field, but the electric flux. The Gauss law is ALWAYS hold, no matter what surface you take. If you take a cylinder, you can be sure that the whole flux through that cylinder will be $q_{int}/\varepsilon_{0}$. If you take another surface, the flux will be also that value (it depends on the charge inside it). The surface must be closed, of course.
But that's the flux, and not the electric field. Knowing the flux can be okay, but it is often very useless. The Gauss law is only useful it you somehow can take $\vec{E}$ out of the integral. For which you need two conditions:
1) $\vec{E}$ makes a constant angle with the surface (preferably 0). Then the scalar product becomes the product of $E$, $dS$ and a $\cos$ that is constant.
2) The surface you chose is such that $E$ is constant along all points of that surface. Only in that case you can take $E$ outside the integral and then it's true that
$ |\vec{E}|= \dfrac{q_{int}}{\varepsilon_{0} \times \iint dS} = \dfrac{q_{int}}{\varepsilon_{0} \times S}$.
This is the basic case, and it's the first they tell us at basic levels (as pointed by @Adithya Eshwarla) But this is only a particular case.
In sum, there's no ambiguity: the flux is indeed that quantity independently of the surface. If what you want is geting the electric field with that, then you must be able to intelligently find a concrete surface in which those two conditions are hold and so you can extract the $E$ inside. As the other answer says, symmetry plays a central role in this task, but it is possible that the system doesn't have any useful symmetry and then you cannot use this law to get $E$.
Also, you can use the differential form instead, as said.
Comment: So basically E can be taken out of the integral If n only if the assumed Gaussian surface is symmetrical(all points on Gaussian surface are equidistant from charge distribution)
Comment: Yes, that's right. This is the central idea of this "topic" of electromagnetism, and I feel is not always highlighted enough.

Gauss law ambiguity


Maximum or Minimum Re-attach

Question: How many times do I need to re-attach? What is the necessary thing to do in order to help my transaction get confirmed?
Answer: There is no fixed number of reattachings to have it processed. The recomendation is to keep reattaching every 30 minutes to 1 hour after the transaction is sent, this way the tip algorithm is more likely to select this transaction because it will be "fresh", since the reattachment proccess will re-do PoW.

Maximum or Minimum Re-attach


Why does a laser beam stay coherent when it passes through glass?

Question: If I have a coherent laser beam and I shine it through some glass, the light will slow down because it will interact weakly with the atoms in the glass. However, the beam that comes out the other side of the glass will still be coherent. Why is this true? Because glass is not a solid, the atoms will be moving quite freely so when the photons interact with these atoms, I would expect the photons to be scattered in many directions. What is actually going on?
Comment: Glass is not solid?...
Comment: @Steeven there is a common myth that glass is a liquid, responsible for a thickening of windows at their bottom. I even saw it mentioned as true in a popular condensed matter textbook
Comment: @JJH [Glass is a solid](https://en.wikipedia.org/wiki/Amorphous_solid) - not all solids have crystalline structure.
Comment: The correct answer is here: https://physics.stackexchange.com/questions/368333/when-light-reflects-off-a-mirror-does-the-wave-function-collapse - Each photon interacts with all electrons simultaneously.
Comment: Can you clarify whether you mean a transparent solid like glass or a transparent liquid like water?
Comment: I mean glass, I'm aware that it isn't a liquid, but it also isn't a solid and doesn't have the crystal structure of a solid
Answer: The light is interacting mainly with the electrons in the valence band (or the conduction band in metals). The oscillating electric field of the light causes the electrons to oscillate, and the oscillating electrons reradiate light that interferes with the incoming light and causes the change in the propagation speed that we describe with the refractive index.
This is a coherent process because on the scale of the wavelength of light the individual electrons are indistinguishable. The light sees the electron density as continuous and smooth so it is not scattered. You specifically ask (in the comments to your question) about amorphous glass, but it makes little different whether the material is a crystalline solid like quartz or an amorphous solid like regular window glass. The band structures of quartz and amorphous silicon dioxide are very similar.
Even liquids have a band structure, though this tends to be rather less well defined than in solids, so the argument above applies to liquids as well. This is why liquids like water refract light in a coherent way.
Having said all this, materials like glass are only approximately continuous and even though the wavelength of the light is about a thousand times greater than atomic scales there is some Rayleigh scattering. This tend to be strongest in liquids, and indeed Rayleigh scattering in water is easily measurable. It is less strong in amorphous solids and less strong again in crustalline solids. However even in liquids the Rayleigh scattering is small compared to regular refraction.
Comment: I think the OP wanted to know the answer in the case of a liquid like water, as suggested by the body of his question. He mistook glass as a liquid, because it is a very popular taught myth.
Comment: @thermomagneticcondensedboson: Nothing in the answer assumes that it's a solid.
Comment: @Ben Crowell I thought the concept of bands made sense in a solid but not in liquids. I guess I am wrong, this is interesting I will investigate.
Answer: Have a look here and the links given to understand that classical light, and photons are two distinct concepts, but classical light  emerges from the superposition of zillions of photons.
As a  classical beam crosses a transparent medium, the photons are affected by the total lattice , i.e. the ordering of atoms and molecules in the glass. The 'slowing down" just means that they travel a longer path length, they only scatter elastically if there is no change in frequency. Coherence at the photon level means that in a transparent medium the phases between the individual photon wave functions are retained. This is what makes the medium transparent, by construction, otherwise it would be opaque. It means that the lattice distances are such that phases are not destroyed. The laser beam , being a superposition of these photons retains the phases too.
This would work for transparent fluids like water: At a $Δt$ the forces are such that an instantaneous lattice can be modelled, it just has a time dependence which is negligible for the velocity of light. ( Glass is not really a fluid)
In addition, if the photons cannot interact with a medium at specific frequencies, then the medium will be transparent, which is the explanation given here for the transparency of some glasses.
Comment: There is no lattice in a liquid, which is what the OP is after. He mistakenly believes glass is a liquid, because it is a very common misconception that is still taught, even up to popular condensed matter textbooks.
Comment: @thermomagneticcondensedboson  This holds instantaneoulsy (in a delta( for water too, The electrical attractions that hold the water molecules together are an instantaneous lattice, imo
Comment: Then I think you can add this comment to your answer, it would be complete IMO.


What deliverables should a web developer expect from a web designer?

Question: Are there a standard set of deliverables a web developer should expect from a web designer? If I was to hire a designer to create what a website should look and feel like, what deliverables do designers deliver? How are they to convey the site design to the person or persons responsible for crafting the markup/backend/styling work. Is there some generally accepted format/standard?
Answer: When we hire a graphic designer/web designer, their packages vary depending on how much we pay. When we pay top dollar ($5,000 - $10,000+ for design and layout, no content), we expect:

Spliced HTML template with all images
Original PSD/Illustrator files where appropriate
License to modify the template as we see fit
We own all IP and do not require attribution to graphic designer
We permit the layout to be used in their portfolio

As we go for cheaper layouts, the first thing to get dropped is the Original PSD/Illustrator files, followed by IP rights. For us the other items are non-negotiable.
Comment: @Thomas - addendum to my last comment, if the designer doesn't know HTML they may include stuff that's not possible, or incredibly difficult, to implement in HTML using CSS. But these issues can usually be worked around in the design stages before signing off on the final layout if at least one person involved in the process knows HTML.
Comment: If you designer did not know HTML you would not hire them? My question was more towards artist designers, no code/markup at all.
Comment: That's a good question. Once I did a website where the designer knew no HTML and it was fine. Photoshop makes it so easy to get a working HTML template out of a PSD I wouldn't have a problem with it.
Answer: Usually the Photoshop PSD file is enough for a developer to splice and code up. The layers allow for easy extraction of overlapping portions and you can always export it to a PNG or any flat format if required. Flat formats (PNG, JPEG, GIF) aren't really acceptable for templates except for the most rudimentary of template designs.
If the designer has specifications for how the template it to be coded, like if there are rollover effects, they should specify that in writing when providing the template as well as any necessary images required for the effect to work. But I find that in general the designer doesn't make any decisions about functionality and are limited to following the specifications provided by the developer.
Comment: Do you require the designer to deliver some accompanying documentation about the fonts, text sizes, how forms should look etc etc? Or do you sleuth it all out of the PSD yourself? A designer cannot design every page of a large website, do you extrapolate from what you have?
Comment: If special fonts were used in the design we do require them to be provided to us assuming there are no licensing issues. In the more complex websites we will have the designer create several page designs that encompass forms, large volumes of text, etc, so we have a basic design for the various different page elements we will ultimately use (forms, tables, etc). For very basic designs (like brochure websites) we can usually take a basic layout and turn it into a website using only one template.
Comment: Its not uncommon to get a branding guidelines document as well.  Including key colours and fonts, line spacing etc for H and P tags etc


When learning new verbs, is it best to memorize both the transitive and intransitive versions up front?

Question: How do you handle learning new verbs that have both transitive and intransitive forms?  Is it best to immediately memorize both forms?
Comment: Slightly off topic for this question, but instead of intransitive/transitive I would memorize the keigo (both humble and honorific) to save yourself the trouble of going back to do it anyway in a few years time.
Comment: Would this be a learning question?
Answer: There are rules to transform each others most of the time, you don't have to memorize both.
Here is a list about 1200 verbs and derivation to transitive and intransitive forms.

http://homepage3.nifty.com/jgrammar/ja/data/trans.htm
Answer: Instead of memorizing the words and which form they are, you should memorize a sentence or two using each form. This way of memorizing is especially useful for transitive and intransitive verbs.
Answer: I would say "yes", it is probably better to learn the pairs (sometimes triplets) at the same time.  That way you can know the context of when to use which one.  If you only learn the 他〜 or 自〜, you may use it incorrectly when you should have used the other one.


No more bubbling after a week

Question: I have made mead a few times with perfect results. This time I tried a Cyser in a 1 gal batch. I followed a recipe that, based on the notes, had good results from others. 1 Gal of 100% apple juice, 2lbs honey, nutrient, and energizer, and using Lalvin 71B yeast. I did everything as he said, half of the nutrient and energizer day 1, then the other half day 2. It bubbled great for about a week, then it just stopped. I've waited for just over another week with no results. OG was 1.100, I haven't taken another reading yet, but wanted to know if I should pitch more yeast, or just leave it alone?
Answer: The key thing with mead is that you need to learn patience.  It should not be done fermenting in a week or two.  Not even a month or maybe not even two months.  Leave it alone completely for at least a couple of months before even thinking about doing anything else to it.  Time fixes a lot of things, especially with mead.
Answer: From my personal experience with wine and beer making, if the fermentation is stuck, it can be a few things, but it usually comes down to the yeast. Either it is too cold, and warming your brew can start it fermenting again. Too hot and the yeast can be killed off, and in some cases, the yeast itself can be faulty. If you think that the temperature is right then, I would opt for a new yeast.

No more bubbling after a week


Keeping your focus/calm during a game

Question: I'm a badminton player, not a very good one though (D-C2 level). Currently I'm having mostly temper-related issues on progressing in my game/winning matches (both friendly and competitive). I'm just too "eager". I was wondering if you guys have any tips/tricks to keep your mind calm and focused on the game so you don't make any "stupid"/faulty moves just because you're going too hard.
Answer: I'd say you need to distract yourself from the bigger picture. Don't worry about the score or your performance or whether you're "better" than your opponent.
Instead focus on

Playing each point in isolation
Making near-perfect movements
Knowing where your opponent is moving on the court

If you can concentrate on those things, the rest of the game will look after itself.
Finally, remember it's only a game, so have fun!
Comment: Not discrediting your advice in any way, but wouldn't focusing on "making near-perfect movements" during competition further exacerbate the OP's issue? It sounds "paralysis by analysis," but I could be wrong. At least in my experience, focusing on technique during competition has been detrimental. I wouldn't mind that piece of advice if [we're sitting here talking about practice, not a game](http://espn.go.com/blog/playbook/fandom/post/_/id/2026/allen-iversons-practice-rant-10-years-later).
Answer: I think this really depends on your ambitions. What is the purpose of you playing the game. I mean, really think about WHY you are playing.
I don't know why you are playing, but for most players (i think?) it's about doing something that makes you feel good. It's probably a mix of getting exercise, playing a game (games are fun), having fun with friends or improving yourself. You should sit down and figure out why you play.
Try and focus on achieving whatever the reason is you are playing. Getting mad, loosing temper/focus is probably not it. I know it's not as easy as saying "Don't do that". Focus on the right things then you will have less time to rage.
I play because i like the exercise, playing games and like to improve at just about anything.
I keep focus on working hard (giving me excellent exercise), trying to win gracefully - like i would in a board game or whatever (having fun) and finally trying out stuff, accepting if it fails - as long as i think it will improve my game in the long run.
When i did my best but still failed i try to look back at it. It can be in the middle of a game (between points) or after a set or whole match. Even when i get home after practice or team tournaments. I try not to regret it - we all make mistakes - and really making mistakes is what helps us improve. I try and take what i can and try not to make same mistake again. It can really also help sometimes, even when stuff does not work out, to try and find ONE thing that did work. It could be one good stroke or placement after a stroke or even after loosing a ball - knowing why it happened and thinking up a strategy for next time. That is a win in itself.
I actually do the same when i'm having success. I try and figure out why it worked but also what could be improved.
You can almost always give yourself small wins. It doesn't have to be about the end result of the match - loosing to a better opponent is probably OK and loosing to someone not as good should give you stuff for thought. Analyze it in your head or ask someone after the match if they saw what the other guy did to mess you up and what you did wrong.
Answer: You should have a look at some professional sports psychologist. In particular Greg Dale from Duke University is particularly good. There is no shortage of research done on this topic. A couple of the most powerful tools are:

Visualization: if you want to stay cool in a match imagine yourself doing so before the game. There is a story that Michael Jordan would visualize games so vividly that he could smell the gum of his opponents. There are many studies showing the effectiveness in visualization.
The three second rule: after making a mistake allow yourself three seconds to reflect on that mistake. Imagine what the correct action would have been in three seconds and then remove that mistake from your memory.
Comment: +1 for visualisation. It has helped my serve immensely to a) look at the net b) imagine the shuttle going over in a nice low arc c) look at the shuttle d) make it happen
Answer: Reading your post, made me think of my younger years !!
It's very difficult to give a conclusive answer, but here's what I have to say about that:

Remember, it's a game you love playing. It's shouldn't be giving you negative energy
The more you practice, the better you will be, at whatever you're practicing. The less frustrated you will be.
There's only you to blame (not shoes, racket, shuttle or opponent)
Try using a personal (funny) word in order to express your frustration, in stead of yelling/cursing.

Watch the following video's from Mr. Jae Bok Lee about: Poor Badminton Player's Behaviour
Part 7, 12 and 13 are particularly of interest. His perception could give you some further leads or inspiration.
Note: I'm not affiliated to the creator of the video's
Answer: Based on my experience with my tennis career.
During crucial points like breakpoints and set points, this is the most fun part. I enjoy being in this situation because honestly during badminton/tennis games, in my opinion 70% mental - 30% physical, if you have strong mental, you are more likely to win games.
During this situation I tend to think of my strategy against my opponent and how I should outplay him, but my mentality is to stay calm and positive as much as possible. I don't rush things, well depends on the situation, I tend to hit his weaknesses or play defensively and force him to commit error. And when I'm in bad shape  like many unforced errors and quite disappointed, my mentality on that issue in order for me to control my temper is to take a deep breath and think what can I possibly do to make my gameplay effective.
All in all, it's on the mental side, try to think positive as much as possible and this never say die attitude, and the most important thing is to have fun. Even though you lose a close match, there may be regrets during that phase but I can assure you, you're having fun on that game.
Answer: Badminton can be a very frustrating game, full of minor skills that take time to acquire. The elements of accuracy speed and deception are part of its charm.
When I was at your level I frequently became angry or flustered. If you really want to improve, it will just take a lot of practice. Learn the rules, learn to serve consistently, learn good court positioning, learn all of the basic strokes. Your opponent will always try to disturb your calm, you should be aware of the tricks people use.
Try to see each game as a contest against yourself, and make it your mission to improve every day. There is no point getting angry, you are not playing in the Olympics (are you?). Play hard and play to win, but remember it is a game, try to keep your ego out of it.
Perhaps pay for some coaching, try to be realistic about where you are at and don't expect to become Lin Dan overnight.

Keeping your focus/calm during a game


Would installing Windows 8 be better than System Reset

Question: I'm trying to fix a fairly new windows 8 system, it has crashed from what seemed a windows system corruption. I tried doing a system reset, it worked fine then i gave it back to the owner. Again it is not booting correctly and it is giving me advanced troubleshooting options. I have a feeling that the recovery or system reset portion is corrupted. Would wiping the drive and re-installing with a Windows 8 be a reasonable attempt. Keep in mind the current recovery and refresh options have Sony bloatware software and drivers installed. I don't think it is a hard drive issue because it is giving me repair options.
Comment: If a system reset didn't fix the problem, its unlikely, installing WIndows 8 again will fix the problem.
Answer: I have had an issue like this before, but it was with a Windows 7 laptop. The first time, the computer fixed itself in recovery, the second time recovery didn't work. After running chkdsk from another computer on the hard drive, the issue was fixed. I thought at this point that the user had been holding down the power button to shut it off or the power cord was coming lose (the battery couldn't old it's charge), which could cause corruption of Windows if this happens at the wrong time. After a while of working on the laptop, I noticed a single "tick" noise every 20 minutes or so. After this, I assumed it was a hard drive malfunctioning. After swapping out the hard drive, and battery (the client wanted a new battery so they didn't have to rely on the power cord) the computer worked fine. It has been about five months since I worked on that computer and the client still is not having issues. The timing between the two events was about a week.
I would try running some hard drive tests on it. Also, ensure that the user is not abruptly shutting the computer off. Another potential problem is a short in the power. Some of the engineers at my work were telling me that the battery could be shorting out if it is a bad battery, causing similar issues. If the battery can hold a change, I wouldn't think this is an issue, but that is assuming this is a laptop.
You are saying that this has Windows 8 on it, so is it fairly new? If so, it might still be under warranty. You may want to engage the manufacturer.
Please post the issue once you find it!


Save one form data in two different channel

Question: I have a form in one page which need to save in two different channel how it can be possible?
using channel form
Answer: I don't believe you can submit to multiple channels at the same time with Channel Form at this time. One option would be to use something like External Entries to create a sql database update. You could then submit your form via ajax to the template with your sql insert/update. (Also see docs for External Entries, subheading "As an Ajax Form", for an example)


How can I move a block when it is placed without the piston interfering

Question: I'm trying to make a redstone device with the new concrete powder where the blocks are being pushed along a row, but every time a block reaches the end, the whole row is pushed up. However, I've tried block update detectors and it doesn't work to power the piston underneath. Because the piston pushes up to where the block reached the block update detector, it powers the piston again, creating an infinite loop. Is there any way to avoid this? I want to avoid making timers, so is there a way to make some sort of pseudo-block update detector that isn't triggered by the piston, or some other device that does the same thing?
Answer: I think I understand what you are trying to make here, and I have came up with this, All you need to do is to make sure that the side piston is set on 4 ticks, and run the observer output into that, this will slow down the piston movement, giving time for the block to be pushed and not creating an infinite piston moving loop.
Answer: In the future, a screenshot of what you're trying to do would be appreciated.
It looks like you want something similar to what is commonly used in semi-auto tree farms to make large, conveniently harvestable cubes of blocks.
You probably want something like what mumbo builds for his tree farm here.
I believe the technical name for this is "smart piston", so if what mumbo builds there isn't in the orientation you want or whatever other problem you can google that to try to find one that work. If you're powering rows of pistons from a single activation, follow what mumbo does to power multiple pistons from one trigger.


Sharepoint Master list, with views seperated across a site - SP 2010

Question: I have a bit of an issue I'd like some input on.
I'm creating a "Master List", with a bunch of different views for different business units in my company.
My original idea was to have a main site, with the master list on it, then subsites that have views of this list, dedicated for different business units.
The idea of this was so that when other business units adds/changes items, the master list will also be updated, as they are the same list just a different view.
So here's my issues:

This list won't be able to be locked down as it is only views right? This isn't the biggest deal, just means that data can be accessed if someone tries to view another business unit's view.
how do I actually separate the list onto subsites? My idea was to add an "Existing list" but apparently my master list doesn't appear as an option on my subsite.

Adding links on the subsites to the main site is an option.. but I'm trying to basically take a secluded view ie. "Finance View" and put it on it's own site so that it's secluded there.
If I can't actually solve this issue, my best bet is to store everything all on one site? with separate areas for the different views? this would mean that data could be seen by different people surely..
Appreciate the help guys
Answer: The List View Web Part can be saved from the parent site as either a file or directly to the Web Part gallery. After that the web part can be added to the sub site.
Please follow steps mentioned in below given link.
Show listview webpart from parent site on subsite in same site collection


How can i turn mobile data on without going into the settings?

Question: I have recently purchased an Iphone 5s, when i turn the mobile data on and off i have to go into the settings. Is there any way i can do it easier? I have tried flicking up from the top and bottom, however cannot find an easier way.
Answer: There is no specific way to turn off only Cellular Data without going into settings.  A (possibly) quicker work around for you would be swiping up from the bottom to get the control center, then turning on Airplane Mode (far left button) and then turning back on WiFi and/or bluetooth.
That would disable cellular data,WiFi, Bluetooth by going into Airplane Mode, and you would get data over WiFi back when you turn that back on.
Comment: I would argue this is a very bad idea for a big reason. This eliminates any ability to use the non-data part of cellular network for non-data reasons such as phone calls, SMS messages, or GPS information.
Comment: I agree, it's not ideal, but it does accomplish his goal.  There are just side affects.
Comment: Yes, but since turning off cellular data is easy in settings, creating an answer that harder and has massive side affects while touting it as a "shortcut" isn't the way I would go. I would simply answer the question as "No, there is no easier way to do it"
Answer: Try the launcher app. It works great into the mobile data settings screen directly from the Today swipe down screen.
Comment: Welcome to Ask Different! Could you [edit] your answer to provide at least a link to the app, and maybe some screenshots showing how it works? As it stands, this is a low-quality answer and may be deleted.


Can I get 240 volts to a hard-wired baseboard heater by plugging into a nearby outlet?

Question: I need some help I have a 42 inch cadet baseboard heater that needs 240 volts to run at full power. The heater is in a small water meter room I have it hard wired in but its only 120volts coming in and I noticed a 15 amp plug close by that is on a different breaker so I was wondering if i can wire a plug to the heater and plug it in while its still hard wired in to get the additional 120 volts so the heater runs at full power or can I just remove plug and hard wire it from there to thanks
Comment: That's one long sentence you have there. Would be much easier to read if you punctuated it a bit.
Answer: You can run a 240V heater on 120V if you really want to, but it'll be weak tea, operating at 1/4 of power.
You could attempt what you hope, but it will require completely redoing the circuit wiring, to have 2 hots and a neutral in the same cable, at least up to the point where a 120V-only subcircuit branches off. All the conductors must be in the same cable. You cannot grab one hot from this cable and another hot from another cable.
Also, the fixed loads on each half of the circuit must account for less than 50% of circuit capacity.  Otherwise you can't have any receptacles on it at all.  This is per pole, so if you have a 6 amp heater on both poles obviously, and a 5A sump pump on one pole, that pole can't have any receptacles.
You must use a 2-pole breaker with 240V between the poles, otherwise you create a serious overload hazard (and also the heater won't work). An example of a bad breaker to use is a double-stuff that fits in one space.
Doing this type of wiring correctly is hard, and easy to get wrong.  It's harder than using punctuation, for instance.
Answer: Theoretically if the two breakers are on different legs, this would work, but it is a REALLY bad idea. This is likely a code violation and it's just not safe to do. You have 2 breakers that operate independently which is not good. Plus you could run into back feed issues.
Comment: This is such a bad idea that you shouldn't even suggest it.  This is just crazy unsafe.
Comment: What if I put a double pull breaker in the breaker box because the breakers are right next to each other


Is there a complement to GPT/2/3 that can be trained using supervised learning methods?

Question: This is a bit of a soft question, not sure if it's on topic, please let me know how I can improve it if it doesn't meet the criteria for the site.
GPT models are unsupervised in nature and are (from my understanding) given a prompt and then they either answer the question or continue the sentence/paragraph. They also seem to be the most advanced models for producing natural language, capable of giving outputs with correct syntax and (to my eye at least) indistinguishable from something written by a human (sometimes at least!).
However if I have a problem where I have an input (could be anything, but lets call it an image or video) and a description of the image or video as the output I could in theory train a model with convolutional filters to identify the object and describe the image (assuming any test data is within the bounds of the training data). However when I've seen models like this in the past the language is either quite simple or 'feels' like it's been produced by a machine.
Is there a way to either train a GPT model as a supervised learning model with inputs (of some non language type) and outputs (of sentences/paragraphs); or a similar type of machine learning model that can be used for this task?
A few notes:
I have seen the deep learning image captioning methods - these are what I mention above. I'm more looking for something that can take an input-output pair where the output is text and the input is any form.
Answer: This is the task of so-called V&L (vision and language models) which effectively encode information from both worlds. There are also many training corpora covering this field already. Here is a quite recent paper on this: https://www.researchgate.net/publication/354617904_What_Vision-Language_Models_See'_when_they_See_Scenes


How to create faces between parent objects?

Question: I have two objects, and one is the parent of another. The reason of the parent relationship is that I want to apply different textures to each object. The two objects need to be bound, so I need to create faces between the two objects, but in edit mode I can only select the vertices of a single object. Can this be done? if not, what's the solution in my case? I need to separate the two objects somehow because I want to apply different textures to them.
Comment: I don't think you can create faces between different objects. You could use some sort of hack by creating curve between them and arraying one more mesh serving as "faces", but the place of joint will be visible.Try to join them and e.g. [apply different materials for those objects](http://blender.stackexchange.com/questions/516/add-different-materials-to-different-parts-of-a-mesh).
Answer: Instead of parenting the object, you need to join them if you're going to connect them, select both and press Ctrl + J, doing so will make them two objects with separate meshes, you can now press Tab to go to Edit mode and work on vertices, edges and faces of both meshes.
You can still create separate textures, assign separate UVs to the same mesh.


Phone Interview Etiquette: Should applicant or interviewer initiate call? Does it even matter?

Question: I have been phone screening several candidates lately and when it comes to scheduling a phone interview I feel I don't know the appropriate etiquette.
Should I call the applicant or should they call me?
Answer:
Should I call the applicant or should they call me?

It's not a matter of etiquette. Instead, it's a matter of convenience.
I almost always conduct an initial screening by phone. When I arrange phone interviews, I have the recruiter set up a time and ask if it would be easier for me to call the candidate, or for the candidate to call me. Since it's easy for me to arrange my schedule such that I can be at my desk near my phone, I will go with whichever the candidate would prefer.
Often, it's simpler for the candidate to duck out of whatever they are doing and call me.
But sometimes they plan on being at a particular place and would prefer that I call them.
Either way works fine. Nobody feels awkward. No breach of etiquette involved.
Comment: Asking candidates about their preference is the best point +1.
Comment: "Instead, it's a matter of convenience." - I would refine that to, "It's a matter of having a schedule/plan". You're trying to get two or more people in touch at the same time. It's not a matter of convenience, it's a matter of being a functional professional and able to arrange a meeting!
Comment: Yeah this is basically what I would say. Only thing I would add is to make sure you determine who is going to call first and have a backup plan.
Answer: The employer should ask what number to call and be open to the reverse if for some reason the candidate does not have or want to give their number.
While most likely not a big deal, by asking them to call you are asking them to foot the bill for a possibly extensive long distance.
Whenever reasonable, expenses should be borne by the company -- for three (interrelated) reasons.  The company can better afford it, not doing so makes you appear cheap, and if you can't afford reasonable expenses in order to hire someone how are you going to pay them?
This doesn't mean that you should book a week long vacation package in Las Vegas for the interview, or even pay travel expenses for an in person interview -- but do keep it in mind when making arrangements.  For instance some companies like to have a casual meeting -- not a formal interview, but a get to know you meeting, over lunch.  The company should be paying for that, not the current employees and certainly not the candidate.
Answer: It depends on the procedure. If the interviewers are in separate locations and can't be on a single speakerphone then all parties will have to call in to a conference system number.
Otherwise either way works. Both parties have logistical issues that have to be resolved, they may not know the number they will be using in advance. Because the company may be doing multiple phone interviews if they can reserve a conference room then that can be the number that the potential employee can call.
Unless I will be doing a single interview by myself I will generally use a conference number even if I will be sitting in a conference room, so that neither party has to know the number in the room they will be using for the interview. I have worked at locations that you can't reserve a small room in advance, and the phone in the cube is not a good place to do your job search.
Comment: Where I work, we also often use conference calls when screening candidates in other countries; making international calls can be complicated and confusing, whereas conferencing systems often have domestic numbers in both locations that both parties will have no difficulty with.
Answer: Going by your other questions, you dont seem to be from the HR.Just curious, why would you bother yourself with these logistics ?
It is almost an industry standard that the interviewer calls the applicant. Even if its a group interview, most of the interviewers will call the conference number and then call  the applicant. As another member pointed out, I would find it out of the ordinary if the interviewers asked me to call them or even asked me for a preference. I take it as a protocol that the HR will decide these logistical details and the interviewer and myself will stick to that schedule.
It has only been once ever that I called into a conference number, that was when the interviewers were in different countries and I was told to call the conference number. If I were given a choice, since I have never been asked my preference before for phone calling, my mind would have wandered off thinking : Why am I being asked this question ? What if I say that I want to be called - will the company think I am being arrogant ? What if I say that I will call - will the company think am desperate for this job ? What is this - a subliminal interview question ? Will the salary offered to me depend on how I answer this ? And so on.
Comment: Not from HR.  I am doing this for a small company that doesn't have HR resources.  I am just doing the technical screening.
Comment: I figured as much. IMO I think it is best for you to be in control of the scenario and tell instead of asking the candidate what your plan is.
Answer: I have done multiple interviews at top well known companies in silicon valley and all of them are pretty much identical in how their interviewing process is setup.
1) after applying on-line or through a friend referral you get an automated email saying that your application if received and will be reviewed (it's nice when they say that it will be reviewed withing X days).
2) after it was initially screened you get a second automated reply saying that they decided to move forward. If not, they usually say that they think that other candidates are a better fit for the position and they encourage to check their other openings and possibly apply there.
3) If they move forward usually on the next business day you'd get an email from an HR from that company asking to schedule a short 15-20 min long introductory call. Some of them ask to provide three alternative dates/time ranges, or some of them send you a link to their calendar where you can select yourself and reserve available spot. When time was selected (manually or through automated web calendar) you'll get confirmation for date and time of the call. Most of them will automatically add that scheduled time to your google calendar (that's best, I really like that, if you have many interviews and every time you need to add events to your calendar manually). They will always call themselves. I interviewed with more than ten companies in the last couple of months and pretty much all of them would call withing one minute of scheduled time :) when you pick up they introduce themselves and always ask if that's a good time to talk (kind of weird question).
In that 15-20 min long call they would ask general questions about my professional experience and explain what the process is like. Pretty much all of the top companies copy-cat the same process.
4) Next step you have to schedule the same way an hour long call with a technical person that conducts online coding test. Usually it's through hackerrank/codility or even simply through a google doc. Here they also call you exactly at scheduled time and after 5-10 min general introduction and discussion they give a coding question to solve. My calls were always finished within 1 hour. After that online coding test the HR person will follow up withing a day or two with the results. Usually if you did well you'll get a really quick follow up: they will congratulate you and ask to schedule a call. On that other call they will offer to come on site for a day-long interview, or they may do the process via email. On that call some (namely facebook) will provide some feedback regarding your first coding test; they usually provide only positive feedback and possibly provide hints where they think you may improve yourself. That feedback is provided but the HR person and not the guy that conducted the interview.
5) onsite interview scheduling is done the same way as scheduling a call: you give a few preferred dates or they offer available dates. If they consider you a high-end candidate and your availability is limited they will be able to schedule on-site interview within a day or two and will manage to book flights and hotels on short notice like that.
6) top employers will offer multiple days at a hotel and flights on days other than the interview, they will obviously pay for all restaurants, and travel expenses. Google for example will rent a hertz car for you (and it wasn't some nissan micro or whatever, it was a nice car).
Usually all that travel associated handling for bigger companies is performed through a 3-rd party company and they try to do their best.
For some reason I noticed that none will pay for hotel mini bar. None will cover alcohol :)
That's an approximate outline. You may also read chapter about interview process at google/facebook/amazon in "Cracking the Coding Interview" by Gayle Laakmann McDowell. In my case interviews at these companies were exactly as described in the book. In all cases interviewers would call me themselves. If I missed a call, I'd callback right away or within a couple of minutes. They have never called me at any other than scheduled time, whenever they needed something, the would ask via email when they can call me. In a few cases, it was also possible to have a skype or google hangout call instead or regular phone call.


Can I attach more filters to a full frame lens on a cropped body without vignetting than with a cropped lens?

Question: It seems to me that because part of the image the lens is passing to the sensor gets cropped due to sensor size that it would take more vignetting to reach the cropped sensor. Is that right and how much would this really be in practice? Is it 1.6x more attachments (which isn't a whole lot) or is there fancier math involved?
Comment: yes, but when you start using more than 1 filter, you start to experience reflections, CA, flare etc etc. Its bad practice.
Comment: Do a simple test: Unscrew your filter from the lens, hand hold it while looking through the viewfinder and start slowly pulling it afar from lens until you start to "see" the filter's ring in the corners of the image, go bak just a little and note how far the filter is from the lens. That distance is what you have to fill up with stacked filters to get vignetting. To overcome non-100% viewfinders, use Live view instead, or shoot sample pics.
Answer: To actually work out a formula would be complicated as it depends on the focal length, but for most full frame lenses in order to vignette when used on an APS-C body, you would probably have to attach so many filters that vignetting would be the least of your worries!
The distance between the corners of a full frame and APS-C sensor is about 8mm. If each filter reduces the image circle by 1mm all round, you would need 8 filters to made their presence felt.


Do I need to pay U.S. taxes on a summer internship in Switzerland?

Question: I did a 10-week internship in Switzerland and earned 5770 CHF. Do I claim that on my taxes? Does Switzerland already figure taxes and therefore I do not have to pay because I can not be taxed twice? I live in the US.
Answer: Were Swiss income taxes withheld from your wages (i.e. the 5570 CHF was what you got in hand after taxes were withheld), or was that the entire amount that you earned -- no deduction for any kind of taxes? Regardless, as a (presumably) tax resident of the US (or a US citizen), your Swiss wages need to be reported to the IRS and you have to pay US income tax on those earnings. You can get a credit for taxes paid or withheld in Switzerland against the US income tax due on those Swiss wages if you file the appropriate forms, so that you avoid double taxation of those wages.
Answer: In general, yes
The U.S. taxes income of all citizens, regardless of where the money was earned.

I can not be taxed twice?

This is patently false.  You can be taxed twice in the U.S. alone via state income tax.  In almost all cases, you can write-down your income based on other taxes paid.
You can attempt to do this alone, but every ex-pat I know pays an accountant to do their taxes.  It's not a common case, and you certainly don't want to screw up as your return will almost certainly be scrutinized.
Comment: "The U.S. taxes income of all citizens…" And permanent residents. And the IRS has a nonresident alien form, but I'm not clear on when NRAs are required to file.
Answer: As of about a decade ago (when I last worked there - I don't know if laws have changed), you will have to start by figuring Swiss income tax - both federal and for the canton you worked in.  (Swiss tax returns were dead easy compared to US ones.) This might have been deducted from your pay.)  Then you can take a credit on your US tax return.  If it's a small amount (likely in your case), it can be taken on Form 1040 Schedule 3, otherwise you have to file Form 1116: https://www.irs.gov/individuals/international-taxpayers/foreign-tax-credit
The upside of this is that you may be able to deduct a standard per-diem amount for living expenses, which is likely to be a good bit more than you actually spent as a student.


Basement Bathroom Drywall Behind Toilet

Question: I'm about to start finishing a basement half bathroom. I have a toilet that sits on an unfinished exterior wall. Should I have the wall drylocked, studs placed, board stock insulation installed, and green drywall put up in order to finish that wall? The toilet's water line causes me some concern about potential condensation that could form within the finished wall. Thanks, any input is much welcomed!
Comment: VTC. Questions remain unaddressed and OP hasn't been back.
Comment: Do you have room behind the toilet to add greenboard / studs or during strips?
Comment: I agree with vtc with so many questions asked that the op never voted or answered comments the close should be automatic unless a really good answer that is upvoted by peers.
Answer: You can slow down condensation on cold water pipes by insulating them.
What?  Insulate cold pipes???
Sure, why not.  The insulation doesn't care. The insulation will act as a vapor barrier to keep humid air away from the pipe, and will greatly slow the warm-up of the pipe.   Remember, in condensing conditions, what is warming the pipe is the enthalpy of vaporization as water vapor condenses.  The water vapor gives up 2257 joules/gram or 970 BTU/lb. when it transitions from vapor to liquid, and this is what warms the pipe until it equalizes to ambient.  The insulation greatly slows this process, reducing condensation greatly.
Answer: The wall is concrete or this is wood framed? Is the exterior wall below grade?
It impacts the answer. but Exterior walls should be insulated. If it is concrete *(which if below grade it better be), then you could just concrete paint it.
If your goal is to have an attractive wall made of drywall, then you should stud it. pressure treated. Before doing this, does the wall have visible leaks? cracks? You can and would want to drylock it if so. And you might prefer then to panel it so that you can have an access door to the areas that concern you.
Follow local code, plastic, etc. As it is a bathroom, and in a basement, certainly get green board if you go the drywall route.
As for moisture, this is a bathroom, if there is a shower/sink, and even just a toilet, go for a vent. It will help you keep this area dry when needed.
As for the toilet itself, once the wall is properly insulated, and the space maintained at a consistent temperature, the only time there would be a real question of moisture on the pipe is if there is a lot of water flow, consistently. This could introduce sweating, but it shouldn't. If the toilet is properly plumbed, and the tank fill shuts off after use, this should never present an issue.

Basement Bathroom Drywall Behind Toilet


Can someone be arrested for having an extremely offensive google play games id?

Question: Suppose the person have put an offensive name like jihadijohn in this form : j1had1john1s1s will he/she get in trouble with police? If yes then how will it be report it?
answer according to india law
Answer: Almost certainly not. There was a provision, section 66a of the 2008 Information Technology Act, which criminalized sending "any information that is grossly offensive or has menacing character" by computer, under which one might imagine pressing a claim. That law was struck down as unconstitutional, because it "infringes the fundamental right to free speech and expression", which is guaranteed by Article 19(1)(a) of the Indian Constitution. Thus "it is not open to the State to curtail freedom of speech to promote the general public interest". It was important to the court's decision that offensiveness is highly subjective.


Why stack canary can be brute-force one byte at a time?

Question: I am reading brute-forcing stack canary. But I am confused why the server can be brute-forced one byte at a time on a crashable-server and what does mean this fork-and-accept ?
Comment: This may help: https://security.stackexchange.com/questions/45593/
Answer: A common mistake, while programming a server, is to use a fork() to start it and respawn it when it crashes.
The problem with a fork() is that is uses a copy of the memory to start over. Of course, using a copy means that the respawned server will be stuck with the exact same canaries even if it has been crashed and respawn. Somehow, it's memory layout and it's canaries are frozen until it is really re-run from the executable file.
The good way to program a server would be to systematically use an execve() in place of the fork(). This ensure that the memory start from scratch an re-initialize all the memory settings (ASLR, canaries, and so on).
But, indeed, most of the servers in the wild are using an execve(), we can only find fork() on old implementations or on educational security challenges.


What are packing cubes and amenity kits?

Question: How to keep track of all things you are carrying in the luggage and where they are? mentions packing cubes and amenity kits.  Can somebody explain or/and elaborate about what these are and how they help a traveler packing clothes?
Comment: You can determine whether a packing cube goes in a backpack by comparing the packing cube's exterior dimensions to the interior dimensions of the backpack.  An amenity kit is also known as a toilet kit, a shaving kit, a cosmetic kit, or, if given to you by an airline (nowadays usually only in premium classes) a goody bag.  To know what these things look like, open the google search page and click the link saying "images for packing cube" (or "images for *whatever-your-search-terms-were*")
Comment: I saw what packing cubes are but unable to understand their significance apart form the fact they are translucent and come in variety of sizes. What those pictures don't tell me is the fact whether these cubes go in a backpack or not ?
Comment: i am looking to understand both packing cubes and (dunno what they look-like) amenity kits and how they help a traveler in packing her/is clothes.
Comment: you can see a small packing cube (yellow rectangle with clear face) sitting on a larger (black mesh with something purple in it) one in the picture on my blog entry here https://transpacifictrip.wordpress.com/2015/03/12/gear-report/ if that helps
Comment: @KateGregory valid point, I've removed my comment! Apologies.
Comment: ["The rule is: only bags go into suitcases, not things. Things go into bags, bags go into suitcases."](https://www.youtube.com/watch?v=ZmD9RkCJgDI&t=13m31s)
Answer: A packing cube is a zippered bag (generally more of a rectangular cuboid than a cube if we want to get into it) for storing clothes and other supplies when traveling. One popular manufacturer is Eagle Creek; I have some Spacepack ones (which I don't think I paid nearly that much for) as well; those have a nice two-sided design so you can separate clean and dirty. A similar product is available in the form of packing folders, which work well for dress shirts, blazers, and slacks. Since they're roughly rectangular, you can pack several up together in a suitcase with minimal wasted space, filling in shoes, sweaters, and other items to occupy any gaps.
The idea is that you can fill them with neatly folded clothes (or tightly rolled up clothes if that takes less space) and other items (such as electronics, they make padded ones), then put the cubes into your bag. This avoids having a bag full of loose disorganized clothes, helping you find what you need and keeping it neat. I'll usually organize things into different cubes based on type: socks and underwear in one, t-shirts in another, button-down shirts and pants in a folder. Unpacking is as simple as pulling out the cubes and packing just involves putting the cubes back in your bag.
Amenity kits are small zippered bags often given by airlines to (usually international) first and business class passengers containing various travel supplies, such as a sleep mask, toothbrush and toothpaste, earplugs, socks, perhaps a comb and a small container of hand lotion, etc... The supplies are useful, but the bags they come in are also handy toiletry bags for future trips. If you don't happen to have your own collection of premium cabin amenity bags, you can buy a toiletry bag of your preferred design, which is what most people do.
Comment: @user568458 I mean there are some advantages, but plastic bags can work too. See [Plastic Bags vs. Packing Cubes](http://petergreenberg.com/2015/01/27/plastic-bags-vs-packing-cubes/). Cubes are also breathable, closable, and look more professional than a heap of plastic bags, if you care. They also make [compression bags](http://shop.eaglecreek.com/smart-compression/l/214) for traveling, which are basically fancy plastic bags with one-way valves on the end so you can roll out all the air. These can be great for packing bulky sweaters and the like.
Comment: Just curious, what can you do with packing cubes that you can't do with plastic carrier bags? A bonus of plastic bags is they can be made to fit any size and shape


Is there a way to force the review of a suggested edit?

Question: I've made this suggestion that fixes an error in a question. It's pending since about 15 minutes, but maybe this delay is normal for this site? If not, is there a way to stimulate the review process?
Comment: I **did** mean that comment to be in jest.... but, re-reading it, it sounds like a 'real' suggestion.... DO NOT post to Meta as a general practice for 'bumping' a suggested edit.
Comment: Be patient!!!!!
Comment: Done ... post to meta and someone will see and review
Comment: @tintinmj: This means **No** to my question? It really wasn't a rhetorical one.
Comment: @rolfl ...and this means **Yes**? What about adding a real answer (even short) that I can *accept*?
Comment: This link should show you what the wedit-review screen looks like: http://codereview.stackexchange.com/review/suggested-edits/14744
Comment: @Wolf Good point about actually answering your question. We're sorry for commenting about the wrong things. I edited my answer which actually might answer your question.
Comment: Upvoted because this ought to be [meta-tag:faq]
Answer: That speed is normal for this site. We are not StackOverflow (and I feel that the speeds for suggested edits on StackOverflow has been increasing lately).
I myself rejected your edit as "Too minor" (Other people will probably approve it though). I would suggest that you instead post a comment on the question stating that you believe it's about problem 32 and not problem 34, and include links to the different problems. It is very hard to verify an edit comment saying "It's about Problem #32, not #34"
To answer the actual question: There is not really a way to speed up the process. The only things you can do is to post on meta (not recommended, because in that case we would have plenty of such requests sooner or later). Another option is to visit the chat room which tends to be quite active actually and let the people there know that you have a suggested edit pending, and while you are there you can also star some of our very interesting conversation messages.
Comment: I would have rejected it as *incorrect or an attempt to comment* - i.e. "is that not *problem 32*?"; but I agree with *too minor*.
Comment: Thanks, I understand that it is *formally* indeed minor, and I already thought about better commenting this suggestion instead. BTW: Is there a way to "rollback" a rolling suggestion?
Answer: I approved the question. For me the question of "too minor" is not about how many characters you changed, but rather how fundamentally you changed the nature of the question. In this case although it was a minor textual change, it was a major change to an important detail of the question.
Comment: @Wolf Now I see that you included a link to `Problem 32`. Sorry, didn't see that before. I do however think that it is better to first post a comment about such "issues" with a question
Comment: I approved as well, for the same reasons.
Comment: Thanks, this is just my idea of the minor-major relation. But it may be better style in this very case to suggest the change via comment.
Comment: I agree that too minor perhaps wasn't the best rejection reason, I mostly miss the links to back the edit. If I would have seen a link to the problems 32 and 34, I would have checked the links and decided whether or not it was a correct edit.
Comment: @SimonAndréForsberg the links are really invisible?
Comment: @Wolf - the links work in the edit review window, but there are multiple displays, one display shows the way the edit visually looks compared to before, and this is great for all the 'fixed formatting' edits that come through. The links are available there, but because of the change, there is highlighting on the link that 'blends it in' to the other changes. The other view allows you to see the markup changes, and the links there are obvious, but not-clickable. Most people review from the 'how it looks' perspective
Comment: @rolfl and this means, that they sometimes don't give much on the edit comment?
Comment: @Wolf editors are often a PITA (like you... ;-) ) and leave comments that don't help. My pet peeve is people (like you) who add/change links but do not say what and why in the comment, or people who add tags and make other small changes to the text, but don't mention the tag change in the comment. IMHO, no link or tag edits are minor, and they are the hardest things to 'spot' in an edit review
Comment: @rolfl does this mean, I have to tell the change itself in the edit comment? I wasn't aware of this, because that wouldn't be a help for me (provided that the changes are shown by the software - as I know it from, say, Wikipedia).
Comment: @Wolf - no, you don't have to, but a comment saying `corrected problem number, added link` is more useful than `It's about Problem #32, not #34` ... because, the change from 34 to 32 is obvious, but the link is not ... ;-)
Comment: @rolfl thanks for the clarifying example. I'll try to improve my edit comments.


What do day-age theorists do with "very good" in Genesis 1:31?

Question: I would like to know what day-age theorists do with what God says at the end of creation - that everything was "very good" (Genesis 1:31)?  That is to say, if you look at the fossil record, you see death, disease, cancer, killing, etc.  So how could God say at the end of creation that everything that He had made was very good?
Comment: I'm confused by your question a little.  Day age creationists would believe that the fossils had not yet been formed at creation.  Did you mean to ask how new Earth creationists view fossilized remains as "very good"?
Comment: Great question.  God said creation was "very good" after all six days.  Is it not the understanding of day-agers that the fossils were laid down during the "days" of creation?
Answer: The best way for me to answer this as a Day Age person is to quote from my main go to guy on the topic, Hugh Ross so I'm going to quote from one of his articles.
Was Evil Present in God's Very Good World
If you read the full article you will notice that Ross shows that the Bible uses the words Good and very good in both a moral sense, as well as in the sense of beauty and aesthetics.

Interpreting tob in Genesis 1
  Tob carries both a moral and a physical appraisal in Genesis 1—the former based on supplementary information in Genesis 3, and the latter on the verb "saw." Hence the essential question is how to weigh these two components: is the meaning more moral than physical, or the reverse? Those who believe that the moral component dominates will typically suggest that God's creation contained not only no real evil, but also no apparent evil. Such interpreters usually picture the original creation as being like the popular concept of "Nirvana"—with no vertebrate animal death or harsh conditions whatsoever. There are, however, severe problems with this interpretation, detailed in our previous TNRTB, "What Does a 'Very Good' World Look Like?" (see here and here.)
  On the other hand, a strong argument can be made that the good God sees in Genesis 1 refers to the aesthetic and/or functional beauty of His creation. This is not to deny the moral aspect of the word tob in Genesis 1, but to emphasize the pleasing sight that God beheld in His work. There is harmony and structure in the creation narrative that points to the harmony and structure of the cosmos. Furthermore, His laws of nature are working together, and something that works harmoniously is beautiful to behold. Additionally, God may have seen Earth as tob because of its potential as humanity's habitat and the place where humans fellowship with the Creator.
Our belief is that the language of Genesis 1 fits better with the aesthetic/functional interpretation. Although it is true that no real evil was present in the original creation, that is not the primary emphasis. Instead, the primary emphasis rests on the beauty of the created order. This is in harmony with the language and biblical theology (Psa. 104; Rev. 4:11). By contrast, there seems little justification for those who claim there is no apparent evil in the created order.
  If we combine the aesthetic and functional concepts of beauty with the moral, one can see why God sees His creation as very good.
Answer: Day-age Theology does not deny the Genesis account; only that a day in Genesis does not necessarily refer to a 24 hour period. I am one. I base my belief on Genesis 1:1 as compared to Genesis 1:3 and 1:5.

Genesis 1:1 KJV  In the beginning God created the heaven and the earth.
Genesis 1:3  And God said, Let there be light: and there was light.
Genesis 1:5  And God called the light Day, and the darkness he called Night. And the evening and the morning were the first day.

There is no way to determine the length of verse one until verse 3. Accordingly in my estimation time began when God said let there be light. Verse 5 says that the evening and the morning made up the first day, which appears to include the first verse in composition of the first day. Logically we would seem to deduce that verse one would be the eternity before verse 3, since the period before light would extend throughout the eternity before the creation of light.
To answer your question about dealing with the statement that "It was very good" we affirm that since at that time according to the Genesis account there was no death. If there was no death there would be no Fossils therefore the Fossil record is not broached.
It is also necessary to accept another Genesis concept that being that if there was no death there would also be no diseases and such that do lead to death; and along with that the concept that there were no Carnivores before no injuries from being killed.
We are also stymied by verses 14 through 16:

Genesis 1:14  And God said, Let there be lights in the firmament of the heaven to divide the day from the night; and let them be for signs, and for seasons, and for days, and years:
Genesis 1:15  And let them be for lights in the firmament of the heaven to give light upon the earth: and it was so.
Genesis 1:16  And God made two great lights; the greater light to rule the day, and the lesser light to rule the night: he made the stars also.

Since the 24 hour day is based on the rotation of the Earth through its darkness and light, would that measurement also apply to the period before creation of the sun, moon, and Stars; after verse 3?
Comparing these verses I find there is room to question whether the Genesis account expounds a 24 hour day or not. while it is true that the Earths rotation is almost a constant 24 hour cycle; it is also clear that not always did the occupants of the Earth account for the extra time that the rotation actually takes. That alone makes a day something other than 24 hours, and if the age of the Earth is quantify 6,000 plus or minus years old do those deny the age as computed by Biblical aging?
In short what we as day-age theorist believe is that there is no conflict between the Bible and true Science, and in the end one verifies the other.
at any rate if we believe that God is in fact the Creator of all things he would not create a World of imperfection, and as the Bible delineates it was man and not God who caused imperfection.
Comment: This sounds more like the Gap Theory than the day-age theory.
Comment: @anonymous2 The Gap theory does not dispute the length of the days only that there was a period between Genesis 1 and 5 of indeterminate length. Day-age proposes that a day as defined in Genesis is not a 24 hour time span.
Comment: Gap Theory says that there was an indefinite period between Genesis 1:2 and Genesis 1:3.
Comment: @Flimzy there is disagreement between Gap enthusiast as to where to place the gap, but all seem to put it between verses 1 and 5.


Can ncRNA convert to coding RNA/mRNA by mutations?

Question: DNA has transcribed into RNA (Non-coding). Can this RNA mutate and become a Protein-Coding one/mRNA? Have there been any such instances reported by scientists?
Comment: The ncRNA will be transcribed from nuclear genomic DNA.  Therefore the mutagenic events would take place in the DNA that codes for that ncRNA gene.  It has nothing to do with the relative chemical stability of the different types of nucleic acids.  There are viruses with RNA genomes, that do not require a DNA intermediate for replication, like Q-Beta, which codes for its own RNA-based RNA polymerase (as I recall).  Are you familiar with the so-called "Central Dogma" of molecular biology? DNA makes RNA. RNA makes Protein (or in this case, the RNA does not code for a protein).
Comment: @mdperry Let me rephrase it: Can a ncRNA (transcribed product from DNA) convert into a mRNA? By mutation, I mean mutation in RNA, not in the DNA which makes that RNA (as it has already transcribed now)
Comment: If you had a gene that mutated its start codon or something, so that it was still transcribed, but the RNA could not be translated, that could be considered ncRNA. If that mutant gene had another mutation that fixed the original error, it might be translated again and become a coding RNA. But mRNAs typically need a start codon, kozak sequence, etc. These features would be hard to find on a ncRNA that didn't originate from a mutated gene.
Comment: @user137 Thanks! I got you! Yeah it seems highly unlikely to have that much modifications/mutations to ncRNA. You made an interesting statement in start of your comment. Can you please explain it further (start codon or something)?
Answer: Answers

Possibly, but with such a low frequency as to be unimportant and undetectable. (Monkeys with typewriters producing Shakespeare's Hamlet comes to mind.)
No. Because it would be extremely difficult to detect, it would seem to be of no importance if it did occur at a very low frequency (you make no suggestion of why it would be of interest) and therefore there would be no reason for anyone to try.

Why would it be difficult to detect?
The difference between mutations that occur in DNA and any that might occur in RNA, is that a mutation in DNA can give rise to a population (e.g. of bacteria, or offspring) all of which carry the mutation. Thus, even though the chance of the particular mutation may be very low (say 1 in a million or less), a situation can arise in which the whole population is producing the RNA transcribed from the mutated gene and the protein encoded by the RNA. If RNA mutation occurs with the same frequency and managed to change a non-coding RNA (perhaps a pseudogene with a frameshift) to a coding RNA, only 1 in a million transcripts would be changed. Therefore if one sequenced the RNA the incidence of such changed RNA would be too low to detect, or if detected would be below the error margin in such experimental work.
Why has nobody looked for it?
Experimental science costs time and money. Scientists explore theories that have an importance and probability of success that attracts competitive funding. If there is no particular reason to look for something and the chances of seeing it are minute, nobody will waste their time on it, and they would certainly not get funded to do so.


How fast can the Galaxy class Starships go in reverse?

Question: I've seen them maneuver. They definitely can go backwards. How fast can they go in reverse? Is warp speed possible, or is reverse limited to impulse power? If it is limited to impulse power, can they travel backwards under impulse power as fast as they travel forwards under impulse power?
Comment: Given an appropriate plot obstacle, the Enterprise can go backwards as fast as it wants to. They always find a way...
Comment: As The Firm put it: "Star Trekking, across the universe; keep on going forward, 'cause we can't find reverse!"
Comment: Well it's a starship. Since they cannot step their foot outside the door for braking (or anything else friction based) and since I've never seen the Enterprise turn around for braking they probably can muster as much reverse thrust as forward thrust, so, same speed forward and backwards.
Comment: I would tend to agree with Eike. The limiting factor for moving in reverse would be ergonomics/convenience and safety. The ship's bridge is forward-facing. The main/navigational deflector is forward-facing, as well as the long-range sensors. It would be very dangerous to travel in reverse at full impulse or warp. But there's no reason why a ship that can seem to accelerate equally fast in either direction can't move as fast in reverse.
Answer: Most Federation ships are not designed to maneuver much under thruster-based power. As far as their schematics go, Federation ships are very limited on what they show for control surfaces for thrust. Given the design limitations, I would give them no more than 1/8 to 1/4 impulse at a full out reverse thrust reaching 5 to 10 percent the speed of light. (and sufficient enough to escape Earth's gravity...)

Why do I think it is so slow? Because there are no specifications for any Galaxy class ship which places a complete and fully functioning impulse engine facing forward for maneuvering control.

I base this on the lack of thrusters shown on their schematics (I am certain this was an oversight/design flaw). See image below:

Could they use some exotic force field arrangement or the deflector array? Perhaps, but that certain seems more complicated than its worth. To be fair, this is not the first time this question has been asked (and unsatisfactorily answered by all involved.) See: Ex Astris Scientia - Sublight Propulsion

Since I didn't like their answer entirely, I decided to try my own.
Mobility and Maneuverability

Most ships have a main dorsal impulse engine and a main hull impulse engine. We assume these engines have a limited capacity to turn, at least a bit, allowing main engines to promote some maneuverability. These engines are the most power non-warp engines on the ship.

Given how nimble most Federation ships, even the Galaxy-class ship, able to make a 180 degree rotation in under three seconds, it makes sense there would not be a major need for a powerful reverse thrust capacity. But even the ability to change direction so quickly requires some kind of attitude adjustment capacity and a very powerful one at that.

One that distributes thrust evenly and across all the surfaces of the ship avoiding shearing stress (though with structural integrity intact, that should be less of a problem)

There are three kinds of maneuvering on any Federation starship.

Warp power: This is the most effective energy to movement power. As far as we know, a ship may change its orientation while in warp without affecting the warp bubble or changing the ships direction. However, we have never seen a ship go to warp without first being aligned in the standard flight configuration.

Impulse Power: This is thrust delivered by the powerful reactor impulse engines. These engines max out at .75c and are used for inner star system, non-emergency flight.

Maneuvering Thrusters: used to navigate the ship at very slow speeds with high degrees of precision. Used in docking maneuvers with space stations, other ships or space docks for repairs. This can be a slow as meters per second or up to hundreds of meters per second (clearing a docking area). These maneuvering thrusters are not prominent on any design specifications but we can make the assumption they are there and are part of the basic hull design.

So where did they hide them?

My theory? In the surface of the ship. Consider such thrusters to be on the flat surfaces of the ship capable of being swiveled and rotated giving directional capacity but remaining flush with the surface of the ship.

Think of them like the tiny fans you see in your overhead when you are onboard a plane. Rotate them to change the direction and intensity of the wind from them. These could be built into the ship as comparatively tiny things linked to the ship's subspace field, becoming more active as the field is intensified.

The subspace field reduces inertial drag, giving the thrusters less ship to move. This removes the issue of why we don't see individual thrusters, they could instead be "thruster clusters" all over the surface of the ship allowing for maximum control with minimum profile.

In the Real World

Using my experience in the US Navy, since Roddenberry was fond of naval ships, perhaps his goal was to consider Federation ships in a similar fashion. Most Navy ships are capable of reverse thrust, used to get into and out of port but this is a very limited capacity. These speeds tended to top out at 1/8 to 1/4 of the ship's maximum forward thrust.

These commands would sound like: "All back full." "All back 1/2" "Back 1/4" indicating how much thrust would be expected to be expended on reversing power. In most cases, this would amount to about 2 - 8 knots top speed (a man could run faster).

Given that most of the design specifications barely seem to consider adding thruster mechanisms of any kind, it would appear obvious thrusters were not considered by the show's designers, who wanted to create visibly elegant ships that were as far away from our bulky rocket-engine-driven designs of ships as possible.
Comment: I watched this recently and you're correct - I'd forgotten. The Enterprise does back off from the probe at half-impulse or so, but it then turns about in order to go faster. The viewscreen still shows the probe approaching, so I suppose it's a rear view.
Comment: This has been here for a while, but I seem to remember two instances of warp speed backwards - the first was in TOS, upon meeting the spinning cube in the Corbomite Manuever. The second was in TNG and I think it was a similar situation - I think it was in the Nth Degree when Barclay boosts the shield output so that they can destroy a probe. Starships can move backwards at warp speed.
Comment: @lunchmeat317 - I took a look at both episodes. In the Corbomite Maneuver, the Enterprise goes backward under command at up to "full impulse" - the top end of sublight speeds. When the command is given to go to Warp 1, no reverse command is given. Until now we have been given clear commands for reverse or spiral course settings. It may be implied the ship is moving in reverse, but when the ship reaches Warp 3, we are left to question if that is possible or perhaps an oversight on the writers part. The only thing that confirms any sort of movement is the visual field is still moving in reverse.
Comment: The TNG episode does not deal with reverse movements only extreme warp jumps to distant parts of the Galaxy to meet the Cytherians.
Comment: TNG: Relics has the Enterprise-D use its impulse engines at full reverse (dialog between Scotty and Geordi).
Answer: Just a speculation as i haven't seen this issue addressed in any episode,

impulse thrusters on federation ships are always directed to push ship forward, with most hull designs having these thrusters on main hull, so there is no hint how it could propel ship backwards, Voyager had them on nacelle pylons, there it would be easy, but may be reverse is done by some complicated system of force fields deployed in thruster exhaust to push ship backwards
maneuvering thrusters can push ship in any direction
warp field is generated around entire ship but hull geometry is binding factor and also the deflector dish is facing forward, if reverse is possible its most likely very limited because deflector cannot project to aft as easily as forward

For Galaxy class reverse on maneuvering thrusters - definitely, impulse thrusters on engineering section are bit outside so some system of reverse thrust quite likely, on saucer are on other hand bit hidden so may be, may be not.
Answer: We have a few examples from on-screen evidence where both Riker and Picard ordered the ship to go in reverse at full impulse (most notably with the Cytherian probe that chased the Enterprise-D).
But, from what we saw, ships can't go to warp in reverse.
And their maneuverability at sublight is actually quite high because all ships seem to employ subspace fields to lower their mass, making even huge ships as nimble as fighters, and able to achieve high sublight velocities (0.25 to 0.75c without relativistic effects since subspace manipulation would be used).
Comment: I can find no references to the Enterprise travelling in reverse at full impulse in [the script](http://www.st-minutiae.com/resources/scripts/193.txt). Picard gives orders to "take us away from it. One quarter impulse" and "full about, go to one-half impulse." It's unclear from the script whether the ship is actually travelling in reverse on either of these occasions.
Answer: I'm pretty sure the science of warp speed is that the starship isn't moving at all. Space is being "warped" around the ship, essentially bending matter and giving the ship the appearance of movement when in reality it's the space that's moving, not the ship. So in theory there is no real reason to have thrusters since as soon as the warp field is collapsed space will return to normal and the ship will slip out and arrive at its destination.
Comment: Can you provide some support for this?
Comment: If space is being "warped" around the ship, what makes you think that this can be done just as easily in either direction?