Proof for the completeness of eigenfunctions of a self-adjoint operator

Question: I always heard the eigenfunctions of a self-adjoint operator form a complete basis. Where can I find a proof in infinite dimension space? Presumably readable for physicists.
Comment: This is a subtle question. Infinite-dimensional self-adjoint operators often have continuous spectrum so one has to generalize the notion of a basis - to a basis normalized to the Dirac delta-function - and they wouldn't be considered bases in most terminologies/axiomatic systems preferred by mathematicians. Physicists know how to use these things and all the rules, including the existence of the basis, follow from a careful generalization of the finite-dimensional case.
Comment: You may always regulate the system so that it becomes finite-dimensional, and then the proofs for the finite-dimensional case become usable - the essence of the proof, as accepted by physicists, is the same for the finite- and infinite-dimensional case. The limiting procedure of the regularization is able to produce new effects, but only when it comes to the number of eigenstates and eigenvalues which may get continuous (or mixed).
Answer: The statement is simply false as it stands when adopting the standard Hilbert space formulation of QM. The true statement is that a self-adjoint operator with pure point spectrum admits a Hilbert basis made of eigenvectors.
(It happens in particular, but not only,  when either the operator is compact or its resolvent is.)
The proof is not so simple and is a particular case of the general spectral decomposition theorem. A proof can be found in classical books on spectral theory like Rudin's functional analysis book,  R&S or Prugovecki's book on mathematical foundation on QM. Even the original and always wonderful von Neumann's book contains a proof (I think the most readable for physicists since there all rigorous spectral theory was invented for the firs time).
The OP's statement admits another interpretation, in the sense of Gelfand's rigged Hilbert space theory. In that case the presence of a continuous part of the spectrum is admitted. That approach is much more intuitive than the pure Hilbert space one but, conversely, is extremely more technical mathematically speaking, also because it needs further topological hypotheses to be established than the standard ones of a self-adjoint operator in a Hilbert space. I do not know a book where a complete proof appears and I suspect that there is not (while I am sure that the statement is correct). The most complete proof I know can be grasped from several propositions in Gelfand Vilenkin's books on generalized functions theory. Perhaps the forth volume. However, some statements about some properties of some relevant measures necessary to achieve the final decomposition statement appear without proof therein.
Comment: Yes, the theorem is in the fourth volume of Gelfand--Vilenkin as stated here: https://mathoverflow.net/a/126758. However, the proof there is not entirely satisfactory as stated there in the comments: https://mathoverflow.net/questions/125655/spectral-theorem-for-self-adjoint-differential-operator-on-hilbert-space#comment705509_126758.
Answer: The operator has to be bounded and compact, or unbounded with compact resolvent for that to be true. You can consult the section on compact operators (chapter VI, Book 1) of Reed and Simon "Methods of modern mathematical physics".


QML examples doesn't run on Windows CE

Question: I built the Qt 4.8.4 examples targeting Windows CE ARM4I platform, everything works well except those examples including QML. They just don't run without error message and I couldn't figure out what is the cause of the problem. Has anyone encountered the same problem and got a solution?
Though it's not essential for me to use QML in my development, I still want to fugure it out.
Regards,
Xuan
Answer: Solved. It's dll problem. Some QML examples need sql, network or other dlls to run.

QML examples doesn’t run on Windows CE


$SU(3)_F$ flavour symmetry and $SU(2)$ isospin symmetry

Question: There is an approximate $SU(3)_F$ flavour symmetry that exists at the quark level between $u$, $d$ and $s$ quarks. But we often talk about an approximate isospin $SU(2)$ between up and down quark only? Why?
Comment: Related question by OP: https://physics.stackexchange.com/q/351805/2451
Comment: SU(2) isospin symmetry is a subgroup of $SU(3)_F$ flavor symmetry.
Comment: The SU(2) subgroup of SU(3) is broken less than SU(3) is broken, that is it is a better symmetry than it. This is so because *u* and *d* masses are much smaller than the QCD scale, but the *s* mass is not--it is comparable, so the "strange part" of SU(3) is split apart from the isospin part, crudely speaking.  Consult a text and WP.
Answer: Both SU(3) flavor and SU(2) isospin are approximate symmetries of the Standard Model at low energies. Consider physics below the proton mass, where we can talk about the pions and kaons that are the avatars of these symmetries. At energies this low, it doesn't make sense to talk about the heavy quarks (charm, bottom, top), so we're left with the light quarks: up, down, strange.
Flavor Symmetry
In the limit where the quark masses are identical, then it looks like there's nothing to distinguish these three quarks. But wait, you might argue, the down-type quarks have different charge than the up quark! This is true, but at low energies, the quarks are all confined into mesons: so we only ever see quark--anti-quark pairs and are not sensitive to the charges of the constituents.
So in the limit where $m_u = m_d = m_s$, we can talk about an SU(3) symmetry that rotates these quarks into each other. It turns out that this flavor symmetry let us relate the properties of pions and kaons in a nice way. For example, you can experimentally measure the decay constant of a pion---something which is not calculable from perturbation theory---and then invoke SU(3) flavor symmetry to say that a kaon should have the same decay constant.
Approximate Symmetry
In reality the pion and kaon decay constants are not the same. This is because in reality, the light quarks do not have degenerate masses and so do not have an exact SU(3) flavor symmetry.
$m_u = 2.3$ MeV
$m_d = 4.8$ MeV
$m_s = 95$ MeV.
This means that SU(3) flavor symmetry is broken by the different quark masses. But we can see from the numerical values that the up and down quarks almost have the same mass. Thus there is almost an SU(2) symmetry where you rotate between up and down. If you have a result which is true in the limit where this SU(2) symmetry were exact, then you can say that the result is true up to corrections that scale like $(m_u-m_d)$. You'll need to write this in terms of a dimensionless ratio, usually in flavor physics the ratio is something like $(m_u-m_d)/\Lambda_\text{QCD}$. Thus we would write:
$$(\text{actual result}) = (\text{result with exact isospin}) \times \left[1+ \mathcal O\left(\frac{m_u-m_d}{\Lambda_\text{QCD}}\right)\right]$$
(Don't worry too much about the use of $\Lambda_\text{QCD}\approx m_{\text{proton}}$ as the heavy scale. The expansion will be something around this value if you're looking light hadrons.)
You can say the same about SU(3) flavor, but now we see that because the strange quark is more than an order of magnitude heavier than the up/down quarks, the symmetry between the strange and the lighter quarks is worse. What we mean by "worse" is that any result that is true in the limit of exact SU(3) symmetry is corrected by something that goes like $(m_s - m_{u,d})/\Lambda_\text{QCD}$.
Note that $(m_s - m_{u,d})/\Lambda_\text{QCD}$ is not a bad expansion parameter. So it still makes sense to use SU(3) flavor as an approximate symmetry. But you can see that SU(2) isospin is more precise at the same order of symmetry breaking.
Notes
Why do we focus on isospin and not flavor symmetry?
A more practical answer to your question may be pedagogical. When learning how to use approximate symmetries to extract physical predictions, it is useful to start with the simpler SU(2) isospin symmetry since this encodes all of the physics intuition. SU(3) is essentially the same story but with more generators and multiple breaking parameters. Thus if your goal is to learn physics, then SU(2) is often sufficient.
What is flavor symmetry good for?
We've noted that quarks are confined, at least at the energy scales at which we would be talking about SU(3) flavor symmetry. In this sense, what good is it to talk about symmetries of the quarks if the quarks are all locked up in hadrons?
The reason is "addition of angular momentum." Well, not angular momentum literally, but the power of using representation theory to decompose product representations. We say that the up and down form an isodoublet. This means that a bound state of two of these particles is in a representation that must be in the decomposition of the product of two SU(2) doublets. We know that this decomposes into an isotriplet and an isosinglet (analogous to the hydrogen atom!). Indeed, these are the pions and the $\eta$. ((There's a little subtlety because the bound states are quark--anti-quark pairs rather than spin--spin pairs in the case of the angular momentum of hydrogen.))
So in other words: flavor symmetry is a way to understand and classify the interactions of the hadrons composed of the light quarks based on the approximate symmetry of the constituent quarks. (Historically isospin was originally identified as a relation between protons and neutrons, but it is identical and we don't have to take the historical view.)
Isn't flavor broken all over the place?
If approximate flavor symmetry is something that came from the more fundamental particle theory of quarks, then maybe we go back to saying that it seems to make no sense that there's a symmetry relating up, down, and strange if these have different charges. In other words, flavor symmetry (isospin) is broken by electromagnetism.
Indeed, the reason why the charged pions are heavier than the neutral pion is precisely because of corrections to their self-energy from electromagnetism. Since electromagnetism has a small interaction strength, this is a reasonably modest correction.
Where did this symmetry come from?
One thing you might also be thinking about is where flavor symmetry came from. Flavor symmetry is a subgroup of the chiral symmetry, which is explicitly broken by the quark masses (Yukawa interactions with the Higgs) and the electroweak force (which treats left- and right-handed particles differently). Chiral symmetry is the observation that one can rotate the left-handed quarks between themselves separately from the right-handed quarks.
This symmetry is spontaneously broken by the same process that breaks electroweak symmetry. The Higgs does this and gives masses to the quarks. The mass terms connect a left-chiral quark to a right-chiral quark, and so rotations among the left-handed quarks must be accompanied by rotations of the right-handed quarks in order to remain invariant:
$$m_q \bar q_L q_R \to m_Q \bar q_L U_L^\dagger U_R q_R$$
is invariant only when $U_L = U_R$. In other words, chiral symmetry is spontaneously broken to the diagonal group. (A quick aside: chiral symmetry is broken by the Higgs, but also at low energies by QCD from the chiral condensate, $\langle q\bar q\rangle$.) The residual symmetry is precisely what we call SU(3) flavor. The fact that it is approximate is again a relic that this symmetry is explicitly broken "by a small amount" by two effects:

The different masses of the light quarks

The electromagnetism, which can tell up quarks from down/strange quarks.

When we have a spontaneous breaking of global symmetries, we know that we are left with a theory of Goldstone bosons. Because the symmetry is explicitly broken, these Goldstones are "pseudo-Goldstones," which practically means that they have a small mass (that is otherwise protected from large quantum corrections due to the approximate Goldstone shift symmetry).
These small mass states are precisely the light pseudoscalar mesons. We know that the interactions of Goldstone bosons is given by the non-linear sigma model, and so we can write down a theory of pion/kaon interactions in the SU(3) flavor limit. This is quite remarkable when we remember that these are bound states under the strong force, which is non-perturbative at these energies.
The other quarks
This should also give an explanation for why we only talk about flavor symmetries between light quarks. The heavier quarks are heavier than the strong scale, $\Lambda_\text{QCD}$ and the symmetry between these quarks and the lighter quarks is very poor.
Comment: Why do we call ($u, d$) isospin symmetry but ($u, d, s$) flavor symmetry? Is there any difference between isospin symmetry and flavor symmetry? or are they just different names but no essential difference? Put it in another way, can we call ($u, d$) flavor symmetry and ($u, d, s$) isospin symmetry?
Comment: Besides, why is the chiral symmetry $U_{L} = U_{R}$ broken into SU(3) and SU(2) but not U(3) and U(2)?
Comment: @Shen: the name "isospin" is historical. The [wikipedia article](https://en.wikipedia.org/wiki/Isospin) gives some insight on the nomenclature: spin was used because (u,d) form a doublet. It behaves similarly to the doublet of the spinor representation. Isospin symmetry versus flavor symmetry are just names. Perhaps in hindsight we could have named them "SU(2) flavor" and "SU(3) flavor".
Comment: @Shen, for your second question I refer to the answer to your query here: https://physics.stackexchange.com/questions/351805/where-does-su2-isospin-symmetry-come-from/353054?noredirect=1#comment1527546_353054


My cheese congealed and I don't know why?

Question: I mixed up a salad in a glass container I added dressing and goat cheese crumbles and shook it up. The next day when I went to eat it all the cheese ended up in a big congealed lump in the bottom of the container.  Did I do something wrong?
Comment: Did you put it in a refrigerator ? If yes, the fat can congealed like if you put olive oil in the refrigerator it become solid.
Answer: I can't comment to ask a question yet, so I'll try to phrase it as an answer. IF you used a vinaigrette, it could be possible that the vinegar broke down the cheese and/or the oil congealed in the fridge, like someone else mentioned.
Answer: I imagine the cheese just "melted" in the presence of all the liquid in the vegetable and dressing.
You should try not prepare you salad a day before; or at least do not shake all the ingredients until you are ready to eat so that the more fragile ingredients do not wilter in the contact of the dressing, or don't add the dressing at that time, have a small container that you can use for the dressing.
If you are short on time, just have all the separate ingredients in different containers and assemble in the morning (or as close as possible to when you will eat it).
For example, have a look at this:
https://hurrythefoodup.com/how-to-pack-a-salad-in-a-jar/
Comment: Sorry, I don't see an explanation here. I don't think that the salad was heated, so the cheese probably didn't melt literally. And using it figuratively doesn't answer the question "why", it simply another description for what the OP already described.
Comment: that's why I quoted the "melted" word; I know , from the OP, it was not heated; maybe; I still think the why because the cheese was in contact with the dressing.
Comment: maybe dissolve would be a better word ?
Comment: Agree with @rumtscho : The primary question was about cause, not prevention. Adding some form of "try a his instead" is nice, but doesn't answer the question. There's also no indication that the asker has problems with leafy greens, other ingredients may not only stand up to dressing, but actually benefit from a certain soaking time.
Comment: 'Dissolve' would be wrong here, since when something dissolves, the result is a liquid, not lumps within a liquid. And the point is not just to find a correct word to name the process, but also to explain why it happened.

My cheese congealed and I don’t know why?


Ocean modifier foam spray?

Question: Is there a way to make the ocean modifier fake foam spray? I already displace the water with dynamic paint, but I still am stumped as to how to create the foam. I'm assuming it's a particle system of some sort, but I'm not where to place the emitter or what general settings to change (I just need some general tips).
Comment: I'm not quite sure what question you're asking, you've mentioned collisions in the question title but seem to be mainly asking how to create boat spray?
Comment: Good point. I wrote half of the question before I figured out how to use dynamic paint, and needed help on just the boat spray. Updated.
Comment: Could you clarify the question? Foam or spray? You mentioned dynamic paint, so I'm guessing you want to know how to spawn collision particles?
Answer: We need dynamic particle emission to do real foam spray. The foam mask in the Ocean Sim modifier was created to be ready once Blender caught up with that feature.
Once Lukas's Particle Nodes project is finished, it should allow for us to do that. http://phonybone.planetblender.org
The foam mask would be the source of the dynamic particle generation. The nice thing about the ocean mesh generated is that there are speed vectors associated with the waves, which I believe should also be able to be sampled and applied to the dynamic particles' starting velocities. Fingers crossed!
Comment: I should also clarify that I'm referring to foam/spray emitted from the peaks of the waves and not object/water interaction.
Comment: do you know the progress of these  features? if you are aware how to do this,  I could post a question if you could answer?
Answer: You could try using a dynamic paint modifier in weight paint mode that makes a vertex group around the object colliding with the ocean, which you could use as an emission vertex group for some particle systems.
Here is a blend file with an example setup.
(Note, only worked for me with the 2.68RC)
However there seems to be a bug where the particles keep emitting
from the same spot.

This is a limitation of the particle system
  implementation unfortunately.
  http://wiki.blender.org/index.php/Dev:2.5/Source/Development/Todo/Tools#Particles
The location of emitted particles are determined in advance now and
  stay fixed, so this can't be animated. There's been some working on
  designing an improved particle system that can handle such animations
  but it's not finished:
  http://code.blender.org/index.php/2011/03/paged-buffers-for-particles/

Ocean modifier foam spray?


1998 World Cup limited edition soccer figure

Question: I bought a limited edition World Cup soccer figure in Paris during the games in 1998, #3005.  It does not have the shell logo on the package -but does say limited edition on the right lower corner. The package also says collect both teams.  Does anyone know anything about this lego figure?
Comment: Do you have a picture by any chance?
Comment: I believe you are referring to a set numbered 3305, not 3005.
Answer: Is this the figure in question?

He's the limited edition English or Scottish team player. The other limited edition figure was a Dutch (Netherlands) player. Lego released an entire soccer theme in 1998 in conjunction with the World Cup, which you can see here on Brickset.
Comment: Yes it is thank you so much. I could only find the shell branded wrapper with searching.


Rocket equation derivation, question about signs

Question: My question is about signs in the derivation of the rocket equation. Considering a rocket of mass $m$, its momentum at time $t$ is $p(t)=mv$. At time $t+dt$ it ejects a quantity $dm$ so its momentum at $t+dt$ is $p(t+dt)=(m+dm)(v+dv)$. The students I tutor asked why it was written m+dm as opposed to m-dm. I was able to convince them that if you considered the mass of the rocket at time $t$ to be $m+dm'$ it worked out to be equivalent, but I think I must have forgotten something fundamental as I was not able to provide a satisfactory explanation for the former case.
Answer: If you the rate of change of mass is $\dot{m} = \mathrm{d}m/\mathrm{d}t$ and we're talking about passing into the future direction ($\mathrm{d}t > 0$), then $\mathrm{d}m$ is necessarily negative. Thus, $m\mapsto m+\mathrm{d}m$ represents a decrease of the rocket mass.
The opposite convention would require that $\dot{m} = -\mathrm{d}m/\mathrm{d}t$ works against the conventional meaning of the derivative in calculus. You could treat that consistently, but it's an extra hassle to intentionally flip certain signs but not others.
Really, the ambiguity is in the "ejects a mass $\mathrm{d}m$". If one understands this as a shorthand for the magnitude, or perhaps something like "ejects a mass, changing the rocket's mass by $\mathrm{d}m$", there's no problem.
Comment: So it's basically conventional to write a differential quantity with a + sign? I guess that makes things easy to explain.
Comment: @k-selectride Right, you can remind them of the the definition of derivative of $f$ as the limit of $[f(t+\Delta t)-f(t)]/\Delta t$. This corresponds to $\dot{f} = \mathrm{d}f/\mathrm{d}t$ in infinitesimal form. Since we know $m$ is decreasing with time, $\mathrm{d}m$ must be negative if $t$ is going forward, etc.


Expected propagation delay of channel fee update

Question: If I change the fee in one of my channels, how long does it take for the update to get propagated through the network? Are there any rough estimates on how long until it reaches, say, 90% of the nodes?
Answer: If a node is directly connected to yours via a direct channel then they should be able to see any changes to the fees immediately upon attempting to route through this channel.
However if there is for example a node multiple hops outside of your channels, likely they would need to wait until a route happens through this specific path before they would be able to verify the fee rate you have set.
So if they are directly connected they can query the fee directly by doing channel re-balancing or something like that, if they are not directly connected they need to learn about the fee rate from multi-hop paths.
This is just from my experience though I'm sure there is a better technical answer.
Comment: I thought that the p2p layer propagates fee updates somehow, even when no transactions are being routed. Otherwise, how can my node learn about the fees of all the channels in the network?
Comment: This could be true, I don't want to say something incorrect technically I am just speaking from what I experienced while using lightning a little while back. If that is true what it means is that the nodes connected to your nodes still need to learn about the fees in-between their channels so they can technically constantly update everytime someone changes their fee rate but I suppose this also introduces a bandwith spam vector and thus probably has some limitation to it.
Comment: For example the lightning watchtowers that can see fees (since you set up a channel with them) probably do not update those fee rates in real time to prevent spam. And someone without access to a lightning watchtower or a channel connected to yours would likely not be able to (or need to) see/verify your fee rates. So in a sense I think it might be more accurate to ask how fast this fee rate propagates to 90% of ln nodes indirectly connected to yours which is not necessarily the entire lightning network. (question seems to imply entire network propagation)


How to re-enable intro videos?

Question: I got the new Left 4 Dead 2 intro video, but when I try installing the .bik file to the respective game directory and start the game, I still get no intro video. After wards I realized that the intro videos could have been disabled. How do I re-enable the intro video for Left 4 Dead 2?
Comment: Have you tried looking at the app launch options? There could be a -novid lurking in there.
Answer: Comment converted to an answer - Credit: Katie aka Ctrl-Alt-Cuteness

The <code>-dev</code> command line argument disables both the intro video as well as the logo video before it. This command is used as it enables the use of some console commands useful for developers of maps & add-ons (both labeled as "mods" in a generic sense for the Steam Workshop).

How to re-enable intro videos?


How to delete a library which is not visible for package manager?

Question: Long time ago I've installed matplotlib which I need to remove. I did it from the source, so if I go to synaptic manager (I use ubuntu) then I don't see matplotlib installed. But I found /usr/local/lib/python2.7/dist-packages/matplotlib. My question is how to correctly delete this library?
Answer: Remove it by a judicious use of rm.
If you installed it outside your package manager, why do you expect the package manager to know how to remove it?
Note that this of course means that any programs that rely on this library won't work anymore, and since it's outside of package management nothing will warn you about it.
Comment: but what about other dependence? Is the library present only in one place?
Comment: That's up to you to determine, unfortunately.  You can do things like ldd to determine if the library depends on others, but it won't tell you if the dependancies are orphaned or not.
Answer: First you should check what version of mathplotlib you have installed. There should be __version__ variable in __init__.py which defines version of lib. Next you need to download sources of this lib from their homepage. After that:
tar xvf matplotlib-VERSION.tar.gz
mkdir ~/temp-mpl
cd matplotlib-VERSION
python setup.py build
python setup.py install --home ~/temp-mpl --record list.txt

After that in list.txt there should be list of files that are installed by mathplotlib in your version. So then you need to replace in it your prefix ~/temp-mpl to path where your mathplotlib is installed and remove for example in this way:
cat list.txt | xargs rm -rf

It will remove all files installed by your specific version of mathplotlib. If you installed some dependencies manually you need to know what it was to remove it.
Remember to remove ~/temp-mpl.
BTW, why you installed it from sources? There is python-matplotlib in repo.
Comment: I cannot guarantee that it will remove all files from `matplotlib` and that it will not remove any other files, so you should be careful...


Filter array with a field value

Question: I need to filter filenames (like DJI_0147_3_5.jpg) in an array, and the code below works, but, where you see a 3 in regex, I need instead a field value.
In the array output (sourcefile field) we have a list of filenames paths and I want to get (filter by "filename" field) only those wich contains the field value inside (not exact match) in the final part (after the second underscore). The field value is "Fab_num", wich is a simple buildng number (ex. 3).

If I put a field instead of 3 it doesn't work.

If I use array_contains, it uses only exact match.
array_get(
string_to_array(
aggregate ('Vettore_unito_a9e2e647_ceed_4b78_8400_1b5e06c8b159',
 'concatenate_unique' ,
 "sourcefile",
 filter:=intersects( $geometry, geometry(@parent))AND
 regexp_match ( "filename", '(_.+_).*3' ),
 concatenator:=',' )
  )
 ,0)

the final 0 is to get the first element in the array. The array is from layer 'Vettore_unito....' wich is a building layer one-to-many (reapeted the same building for every photo related to it).
Comment: Not a solution, just a hint: instead of `array_get( [your_array], 0)`, you can use `[your_array][0]` - adding a number (index) in square brackets at the end of an array returns the n-th element of the array.
Answer: The following expression should work:
array_get(
string_to_array(
aggregate ('Vettore_unito_a9e2e647_ceed_4b78_8400_1b5e06c8b159',
 'concatenate_unique' ,
 "sourcefile",
 filter:=intersects( $geometry, geometry(@parent))AND
 regexp_match ( "filename", '(_.+_).*'|| "fab_num"  ),
 concatenator:=',' )
  )
 ,0)

Filter array with a field value


How to specify the right device names when using Ignition for installing Flatcar Linux?

Question: I am currently using Container Linux for my home server and I want to upgrade to Flatcar Linux. To do this I plan to use Ignition and configure RAID 1 for the root filesystem.
I have two disks dedicated for the root filesystem and the rest form a BTRFS array for extra storage, so I want to make sure not to overwrite the BTRFS disks. The root disks for Container Linux currently register as /dev/sda and /dev/sdb. My understanding is that the names of these disks depends on which Linux kernel you are using and other random boot factors.
How can I make sure I pick the right disks in my Ignition configuration? I guess this is a very common issue but I can't find anything specific to Container Linux/Flatcar Linux.
Answer: I solved this using the WWNs in /dev/disk/by-id.


What do the contents of the general purpose registers contain?

Question: I included the iOS tag, but I'm running in the simulator on a Core i7 MacBook Pro (x86-64, right?), so I think that's immaterial.
I'm currently debugging a crash in Flurry's video ads. I have a breakpoint set on Objective-C exceptions. When the breakpoint is hit I am in objc_msgSend. The callstack contains a mix of private Flurry and iOS methods, nothing public and nothing that I've written. Calling register read from the  objc_msgSend stack frame outputs the following:
(lldb) register read
General Purpose Registers:
       eax = 0x1ac082d0
       ebx = 0x009600b5  "spaceWillDismiss:interstitial:"
       ecx = 0x03e2cddb  "makeKeyAndVisible"
       edx = 0x0000003f
       edi = 0x0097c6f3  "removeWindow"
       esi = 0x00781e65  App`-[FlurryAdViewController removeWindow] + 12
       ebp = 0xbfffd608
       esp = 0xbfffd5e8
        ss = 0x00000023
    eflags = 0x00010202  App`-[FeedTableCell setupVisibleCommentAndLike] + 1778 at FeedTableCell.m:424
       eip = 0x049bd09b  libobjc.A.dylib`objc_msgSend + 15
        cs = 0x0000001b
        ds = 0x00000023
        es = 0x00000023
        fs = 0x00000000
        gs = 0x0000000f

I've got a few questions about this output.

I assumed $ebx contains the selector that caused the crash and $edi is the last executing method. Is that the case?
$eip is where I crashed. Is that usually the case?
$eflags references an instance method that, as far as I know, has nothing to do with this crash. What is that?
Is there any other information I can pry out of these registers?
Answer: I can't speak to iOS/Objective-C frame layouts specifically, so I can't answer your question about EBX and EDI.  But I can help you regarding EIP and EFLAGS and give you some general hints about ESP/EBP and the selector registers.  (By the way, the simulator is simulating a 32-bit x86 environment; you can tell because your registers are 32 bits long.)
EIP is the instruction pointer register, also known as the program counter, which contains the address of the currently executing machine instruction.  Thus it will point to where your program crashed, or more generally, where your program is when it hits a breakpoint, dumps core etc.
EIP is saved and restored to implement function calls (at the machine code level -- inlining may result in high-level language calls not performing actual calls).  In memory-unsafe languages, a stack buffer overflow can overwrite the saved value of the instruction pointer, causing the return instruction to return to the wrong place.  If you're lucky, the overwritten value will trigger a segfault on the next memory fetch, but the value of EIP will be arbitrary and unhelpful in debugging the problem.  If you're unlucky, an attacker crafted the new EIP to point to useful code, so many environments use "stack cookies" or "canaries" to detect these overwrites before restoring the saved/overwritten EIP, in which case the EIP value may be useful.
EFLAGS isn't a memory address, and arguably isn't a general purpose register.  Each bit of EFLAGS is a flag that can be set or tested by various instructions.  The most important flags are the carry, zero and sign flags, which are set by arithmetic instructions and used for conditional branching.  Your debugger is misinterpreting it as a memory address and displaying it as the closest function, but that isn't actually related to your crash.  (The + 1778 is the giveaway: this means EFLAGS points 1778 bytes into the function, but the function is unlikely to actually be 1778 bytes long.)
ESP is the stack pointer and EBP is (usually) the frame pointer (also called the base pointer).  These registers bound the current frame on the call stack.  Your debugger usually can show you the values of stack variables and the current call stack based on these pointers.  In case of corruption, sometimes you can manually inspect the stack to recover EBP and manually unwind the call stack.  Note that code can be compiled without frame pointers (frame pointer omission), freeing EBP for other uses; this is common on x86 because there are so few general-purpose registers.
SS, CS, DS, ES, FS and GS hold segment selectors, used in the bad old days before paging to implement segmentation.  Today FS and GS are commonly used by operating systems for process and thread state blocks; they were the only selector registers carried forward into x86-64.  The selector registers are generally not helpful for debugging.


Using directive and namespace aliasing with Ksh

Question: Can I create an alias for a korn shell namespace?
Is there anything like the using directive in C++ (bring several namespaces together and throw a (compiler) error if a symbol designation is ambiguous)?
Comment: Can you make your goals a clearer here? Maybe an example or two demonstrating conceptually what you'd like to accomplish? Also, since I'm pretty sure that your acquaintance with the Korn shell can't be more than a few hours old, maybe you should try reading through all of its `man` page and generally poking at the interface a little more to get an idea about how things work before asking specific questions about implementation details? It could be what you want and what you might want if you knew better are two very different things. At least, it usually works that way for me.
Answer: Even though ksh has more advanced feature than other shells, it's still at its heart a language to automate simple task and write small scripts, not a language geared towards writing huge applications. You can't expect to have all the features of a typical language designed for large applications, let alone all the features of C++.
I don't think you can create an alias for a namespace. You can create a copy of a namespace of sorts by enumerating its variables (parse the output of typeset +p or typeset -p, or use ${!.foo.*} if you want to include variables inherited from the parent namespace) and copying them one by one. You can make a variable an alias of another with typeset -n, but that only takes effect when used inside the namespace:
$ namespace foo { x=1; }
$ namespace bar { typeset -n x=.foo.x; echo $x; }
1
$ namespace foo { x=2; }
$ namespace bar { echo $x; }
2
$ echo ${.bar.x}
.foo.x

Ksh lets you go further and execute arbitrary code when a variable is read, modified or unset, with discipline functions. For example, if you define a function called x.get, this function is invoked each time the value of x is retrieved.
namespace bar {
  x.get () { _=${.foo.x}; }
  x.set () { .foo.x=${.sh.value}; }
  x.append () { .foo.x+=${.sh.value}; }
  x.unset () { unset ${.sh.name}; }
}

I think you have to define these for every variable, and you can't detect variables that are added to the namespace foo.
This can be extended to look up multiple namespaces.
x.get () {
  if ((${.foo.x+1}+${.bar.x+1}!=1)); then
    echo 1>&2 "Ambiguous variable x, available in more than one of foo and bar"
    exit 125
  fi
  _=${.foo.x-${.bar.x}}
}

Comment: I'll take a risk - but this is *really* good. It's just... have you looked at `typeset -T`? With `-T` you can type - or template - a compound variable, which, as I think, could fill the gaps here. It's like a C struct. And you can use it to define your own disciplines. When you've defined a type you get a new builtin assignment command for it - and your subvariables *(including disciplines)* are copied over for each new instance you define with it. And all of that is not to mention that `ksh` is extendable w/ C or C++ libs.


VS2015: Unable to cast COM object of type 'System.__ComObject' to interface type 'IFabricTestManagementClient4'

Question: I am using VS2015 for this particular project but also using VS2017 for other projects.
Installed: Microsoft Azure Service Fabric SDK                                                                         - 4.0.466.9590
VS Project Target framework: .NET Framework 4.6.2
VS reference System.Fabric: Runtime Version v4.0.30319 - Version 220.127.116.11
When I try to debug the application in VS2015, it turns out that it's throwing an exception when:

Unable to cast COM object of type 'System.__ComObject' to interface
  type 'IFabricTestManagementClient4'. This operation failed because the
  QueryInterface call on the COM component for the interface with IID
  '{B96AA7D4-ACC0-4814-89DC-561B0CBB6028}' failed due to the following
  error: No such interface supported (Exception from HRESULT: 0x80004002
  (E_NOINTERFACE)).

Can you help how to debug/resolve this issue?
Answer: This is usually caused by a mismatch between the service code + nuget packages and the software version of the cluster.
The easiest way to fix, is to update everything to the latest version.


Make my computer screen's tint warmer at night?

Question: I use my computer at night, but my computer screen looks like daylight and I find it too bright to use at night.
So, what is a good tool to make my computer screen warmer at night? I'm using Windows 7.
Answer: A tool that you can use for this purpose is f.lux. Just enter your location, and the lightning that you have. Then, at night (the time between sunset and sunrise), f.lux will give your screen warmer colours, and during day (between sunrise and sunset), f.lux will make your screen look like daylight.
It works good and is cross platform, but the disadvantage is that it could be that you, even after sunset, don't yet feel the need of making your screen warmer. So you shouldn't think that with f.lux, you will never have to adjust the brightness of your screen manually.
Answer: redshift was designed to do that, in the background, and even doing a transition while the sun is not yet fully gone:
redshift – Adjusts the color temperature of your screen
The color temperature is set according to the position of the sun. A different color temperature is set during night and daytime. During twilight and early morning, the color temperature transitions smoothly from night to daytime temperature to allow your eyes to slowly adapt.
Answer: This is now a built-in feature in Windows 10 called Night light. You can enable it by following the instructions in this article on Microsoft Support.

This is an old question and you mention that you are using Windows 7. If this is still the case, I would recommend upgrading to Windows 10 by following the steps in this article on The Verge. Apart from giving you a native solution for twilight mode, updating to Windows 10 will come with significant security improvements to your machine.
Comment: Thanks, and no, I'm no longer on Windows 7. I upgraded to Arch Linux ;-)


Windows update not updating drivers

Question: On Windows 10, I have read that all driver updating is done through windows update. Yet if I go into device manager right after running windows update, and check for driver updates, I find that there are some updates that are still available. What am I missing in window update settings to update these?
Comment: Installing device drivers through Windows Update is still an optional setting in Windows 10.  This a personal or corporate computer?
Comment: @Ramhound where is this setting?
Comment: @Moab - [Disable automatic driver update for only one device in Windows 10](http://superuser.com/questions/1096937/disable-automatic-driver-update-for-only-one-device-in-windows-10?rq=1).  The differences in the drivers could be explained by the fact, at some point other drivers were installed, device manager lists any drivers for the device.  Windows Update is suppose to only download the current version of those drivers.  More specific information about the drivers would be required to fully explain the behavior.
Comment: That is a "temporary" driver block, more microsoft bullcrap.
Comment: I have this exact problem right now, it happened after upgrading to 1803, no hidden updates but no drivers listed on windows/microsoft update
Answer: While Windows Update can pull down generic drivers that will work fine for most users and applications, if you want the latest drivers for your specific hardware, your best bet is to get it from the computer manufacturers website. Also, if you are on a domain environment, there may be group policy in place that is preventing you from pulling down driver updates.
Comment: Does not answer why device manager conflicts with windows updates not finding any driver updates, both use the same service to find driver updates.

Windows update not updating drivers


Opposite category of SET is Boolean Algebra

Question: I'm reading introductory notes on category theory. While discussing the notion of opposite category, the author makes a remark that if we take opposite category of SET, that is $SET^{op}$ category, we will get the (isomorphic) category of Boolean algebra. But the book didn't explain it beyond that. I would like to know why this is so? Taking the opposite category simply change the direction of arrow, how can this changing the arrows direction results in a Boolean algebra? Any answer to build intuition or any suggestion of reference that does it in elementary way--that is without using advanced theorems in category theory?
Comment: It's not the category of Boolean algebras but the category of complete atomic Boolean algebras. There's also a natural Boolean algebra structure associated with a set and that assignment conveniently extends to a contravariant functor on $\mathbf{Set}$. You may attempt to derive the result yourself from this by trying to explicitly construct the equivalence.
Answer: This isn't quite true. But the idea is that the opposite of the category of sets may be thought of as the category of powersets and morphisms preserving intersections and unions, since to every function $f:S\to T$ there uniquely corresponds such a function $f^{-1}:P(T)\to P(S)$. Furthermore, $f^{-1}$ is a Boolean algebra homomorphism. This sets up an isomorphism between the opposite of sets and a certain full subcategory of Boolean algebras, namely that whose objects are powersets.
It's true that the opposite category is just some formal construction involving arrows. The point of this example is that in certain (rare) examples, the opposite of a category is isomorphic to some familiar category. Most other examples of this kind are categories which are isomorphic to their own opposite, such as the category of sets and relations, and the category of finite-dimensional vector spaces.


Can't select a disk to install High Sierra

Question: I have a mid 2010 MacBook Pro currently using MacOS X El Capitan 10.11.6. I downloaded MacOS High Sierra 10.13.4 and have the "Install MacOS High Sierra" application. My problem is that when I try to install MacOS High Sierra, the only available disk to select is "Restore Image," which "Install MacOS High Sierra" tells me is used for Time Machine backups, but it is gray and faded and I can't select it. I have FileVault turned off and "Restore Image" selected in my "Startup Disk" menu. How can I be able to select the disk and install MacOS High Sierra 10.13.4?
Comment: Is this a new installation?  Did you wipe (partition) the disk with Disk Utility?
Answer: I think the installer is not allowing you to install because you need to FIRST update the firmware.  You do this by making a USB installer from the installer app and booting to it.
https://support.apple.com/en-us/HT201372
You will need to choose HFS+ as the format and the High Sierra Installer will convert the disk to APFS (if the target drive is an SSD).


Hybrid power supply output voltage

Question: I have a question. I want to make 30V/4A hybrid power supply with stepdown regulator LM22679 as an preregulator and LM338 as an linear regulator to smooth voltage. LM22679 would be powered by Mean-Well power supply with output voltage of 36 V. When I want let's say 10V output voltage, from 36V input I make about 14V with buck regulator and then there would be lower voltage drop on LM338 when making 10V from 14V instead of making 10V from 36V. My question is how to simply control output voltage? If I can somehow use LM338 as Vin=Vout regulator, I can simply set only output voltage of preregulator with one potentiometer but I am afraid that i cannot do that. I hope you can understand what i mean. Thank you.
Comment: Welcome to EE.SE! A schematic is worth more than a thousand words.
Answer: You could try a circuit like the one below.
R1 provides bias for the zener, while R2 and C form an RC filter to reduce the unwanted ripple from the switched power supply (if you have no filtering, you defeat the purpose of using a linear regulator because the LM338's output voltage would carry all the ripple from the switched regulator).
The LM338 output voltage should follow its input voltage minus ~3.9V, what provides an appropriate dropout voltage for this regulator. The output voltage could be controlled by a potentiometer connected to the feedback line of the LM22679, as you suggested.
Disclaimer:

I haven't tested or simulated this circuit
the choice of values for the discrete components may be a little tricky

Other comments:

I'm not sure how clean you need your output to be. Keep in mind that you can reduce the ripple of the switched power supply by simply increasing the inductor and capacitor values. Depending on the load, you could also have a simple RC filter in front of it to further reduce the ripple from the switched power supply

simulate this circuit – Schematic created using CircuitLab

Hybrid power supply output voltage


Procedure & rules to be followed while listening or narrating puranas?

Question: I want to ask about procedure and  the rules to be followed while listening or narrating the puranas and Who can read the Puranas?
Comment: [How to read Hindu Scriptures](http://hinduism.stackexchange.com/questions/15693/how-to-read-hindu-scriptures) may help you.
Answer: The general rules the listener and narrator should have to follow , while listening or  narrating the  puranas are given Shreemad Bhagvat Maha Purana  and in Shiva-MahaPurana (Chapter 7 –Description of worship of the book and the orator) .
Before starting reading or narrating puranas one should do a Sankalpa , Its highlighted that one should listen or narrate the puranas with pure and deep devotion .Only with  pure devotion and pure love towards god gives respective outcome of listening or narrating of puranas.
Some of the  shlokas describing procedure and the rules to be followed while listening or narrating from Shiva-Maha purana chapter 7

आसमाप्तपुराणं हि समुपोष्य सुशक्तिमान
    श्रुणुयाद्भक्तित: शुद्ध:पुराणं शैवमुत्तमं॥६॥
Or a listener who is quite healthy ,should keep fast till the end of
  the Katha ,getting purified. He should listened to the story of
  Shiva-Purana with devotion.One should listen to the katha with comfort
  consuming Ghee or Milk
  घृतपानं पय: पानं कृत्वा वा श्रुणुयात्सुखं
    फ़लाहारेण वा श्राव्यमेकभुक्तं न वा हि तत्॥७॥
The orator or speaker should consume fruit or take food  once in a
  day and recite the Shiva-Purana.
  पलाण्डु लशुनं हिङ्गु गृञ्जनं मादकं हि तत्:
    वस्तुन्यामिषसंज्ञानि वर्जयेदय: कथाव्रती॥१२॥
Onion ,Garlic ,asafetida ,carrots and other intoxicating Drinks should not be consumed by the person listening to the
  katha daily.गृहस्थच्श्रेद्भ् वेच्छोता कर्तव्यस्तेन
  धीमता होम: शुद्धेन हविषाकर्मणस्तस्य शान्तये॥३६॥
In case the listener is a House-Holder , then the wise people should  perform homa with pure ghee of cow for Shanti of Katha.
  Some of the  shlokas describing ,Procedure and the rules to be followed while listening or narrating Shreemad Bhagvat Purana , which are given in Shreemad Bhagvat purana (Mahatmya or glory part) which is originally from Skanda purana vaishnava kanada , bhagvat mahatmya
एषोsप्यत्युत्तम: पक्ष: सप्ताहो बहुसंमत:
  Experts say that its best to read Shreemad Bhagvat purana in 7 days.
पुस्तकं च गुरुंचैव पुजयित्वोपचारत:
  One should pray and honour Purana book and Guru Ved-Vyasa everyday before reading or listening.
  पयसा वा हविष्येण मौनं भोजनमाचरेत
    ब्रह्मचर्यमध: सुप्तिं क्रोधलोभदिवर्जनं  ॥४४॥
    One should only consume milk during those days and maintain celibacy , one should sleep on floor without bed ,and must keep one-self away from anger and lust.
  कथान्ते कीर्तनं नित्यं समप्तौ जागरं चरेत
    ब्रह्मणान् भोजयित्वा तु दक्षिणाभि: प्रतोषयेत ॥४५॥
  After compilation of story , each day kirtan should be performed and at the end of reading or listening of purana. Jagaran (not sleeping whole night while singing songs of god) has to be observed.


What are the coins John Wick is using?

Question: In the movie John Wick, the title character is using some kind of gold coins to pay for cleaning his house or for the receptionist and to enter the bar.
So my question is: What type of coin is he using?
Answer: This is discussed in the one of the video extras that were released to advertise the movie.
In short, the coins were custom-made for the film and represent a secret currency used by the society of assassins (of which John is a member) with which one can purchase a variety of services including body disposal, medical care, accomodations and transport.
Quoting from the video linked about;

One side of the coin is Peace and Violence in one character, the other
side is a Lion (for strength) and a Shield for protection because
these coins, if you've got one, you're protected
Answer: The video link in the other answer no longer work, but after using the wayback machine to check an older iteration, we could see the page was titled: Exclusive clip: The assassin's code of 'John Wick'.
The video can be found on Youtube: John Wick (2014) The Assassins Code - Featurette.
The quoted passage in the other answer happens at 3:17:

Starting at 2:41, we get explanations as to what the gold coin represents in universe from various people who took part in the movie:

Adrianne Palicki (Ms. Perkins): Apparently, if you have a gold coin, you can pretty much get in [the Continental] and get pretty much everything you need.
Dan Leigh (Production Designer): The gold coins are, in a way, sort of the private credit card.
David Leitch (Producer): The gold coins are kind of like your entrance into the world. Not only do you have to have the wealth to... to be in this sort of underworld, you have to have that type of wealth where you can drop a thousand bucks and enter these places. But it's more like a membership.
Keanu Reeves (John Wick): We deal in a currency of gold. Gold coins are passed amongst us. This special group.
Adrianne Palicki (Ms. Perkins): You can get somebody to remove bodies for you, you can get a doctor that's not going to go to the cops.
Dan Leigh (Production Designer): That gold coin identifies them with each other and it's their way of moving through the process. One side of the coin is peace and violence in one character, and the other side there's a lion for strength and a shield for protection. Because these coins also, if you've got one, you're protected.

We are also given an explanation from Berrada in the third movie, around 52:50 into the movie:

Berrada: You see that coin? The first coin ever minted in this facility. Next to it, the first Marker. Not easy to track down, believe me. Now this coin, of course, it does not represent monetary value. It represents the commerce of relationships. A social contract in which you agree to partake. Order and rules.

Also, here's a picture of Winston holding a gold coin from the second movie, when John was paying him a visit as he was analysing gold coins to be put into circulation:

Here's that same picture, tilted to the left for convenience of looking at the coin. You may notice lines that look like those were 3D printed, unlike the ones from the other answer:
Comment: Normally, I would have just edited the dead link of the other answer and call it a day, but I figured I might as well write my own answer when I realised I would be adding too much information.

What are the coins John Wick is using?


How would volcanism be different on a terrestrial planet denser than earth?

Question: Specifically, how would volcanism be different on a terrestrial planet with these parameters:
Mass: 0.38 Earth
Radius: 0.7 Earth
Density: 1.1 Earth
Comment: Why is it denser if it is smaller? There would be less gravity compacting its mass. Does it have a lead core instead of an iron one like Earth?
Answer: The lower mass and radius implies that the thermal capacity of the whole planet is lower than the one of Earth. This means that, all the rest being the same, the planet will cool down faster.
Cooling down faster means that volcanism will be active for a shorter time than it is on Earth: once the mantle is solid there is no way for having tectonics.
This is similar to what happened to Mars (which has a radius 0.5 Earth).
Answer: Given that the radius of the Earth is "1" and the new planet is "0.7 Earth" then the volume of your planet is 34.3% of Earth.
It appears you then multiplied your desired density (1.1) by that number to get 0.38 mass. Except that it wouldn't work that way. (Click on the image to see the full-sized version.)

You have less volume to work with and you can't simply jump to using lead or another metal that's more dense than nickle-iron to get your density increase. That means the inner core is a much greater percentage of the planetary volume than Earth enjoys.
Further, the crust, to keep that density somewhat in balance, will likely be thicker. This is probably necessary if only to keep the heat inside the planet longer.
The consequence is that the outer core and mantle are much thinner than on Earth.
What does this mean? IMO, it means much less volcanism once the crust has cooled and people could theoretically live on it. The thicker crust will keep the heat at bay and make it harder to pierce.
Further, the reduced mass of the planet means less pressure at the core, which means less pressure for volcanism to take advantage of.
IMO Conclusion
Much less volcanism and a much cooler surface (due to planetary warmth, which has nothing to do with solar heating). When it does happen, it will be sluggish compared to Earth due to the lower core pressures.
However, the ejecta will have a much higher metal content due to the much smaller mantle and outer core regions. Consequently, I would expect the crust itself to be much richer in metals.
Disclaimer
I'm ignoring current science about how planets are formed. I believe I'm free to do this because we constantly find exoplanets that blow everything we know about planet formation out of the water.
My conclusion is that you want as a starting point (you don't mention it, but what would be the point if I'm wrong), a planet that is useful in your story and therefore needs to be something more than a big rock in space.
Generally speaking, unless acted upon by gravimetric forces (like a moon around Jupiter) or solar wind (like Mercury), a planet this small is most likely to be just a big rock in space with basically no volcanism at all...
...unless the solar system was very, very young.
Now that I think about it, you didn't provide nearly enough details for an objective answer....
Comment: Yeah, sorry about that, i am new to this site and still figuring out how to ask questions properly, thank you for your answer.
Answer: Well
The Surface Gravity is 5,33m/s² after a = GM/R². Which is not a lot but still more than Mars. What makes this case interessting is that the Density is at 6,07g/cm³. Which is more than any major Body in the Solar System.
What does this tell us ?
The Planet is unlike anything we have in the Solar System. The Density and small Radius suggest that it is made out of Heavyer Elements. And Remeber, this is the Avg. Density. So if your Avg. Density is so much higher, that also suggests that the Change in Density from the Surface to the Core is less drastic than for example on Earth.
This then points to a very Dense and large Core.
If i had to guess how something like that would become a thing, i would say that a Proto Planet collided with your World and basically removed the higher layers. Sort of like the Moon did to us. But on a Grander scale.
A collision like this would, as i said, remove most of the light elements. It would also intruduce a lot of spin. Not to mention the giant Moon in the sky. Depending on the Impactor, your World and the Moon could have a 2:1 Mass Ratio or even greater.
This Giant moon pulls on the Planet with such a Force that it would deform the Planet. After a while it would more or less be a Giant Lava See. Duo to a lot of Forces, the Moon and your World would become Locked to each other. At the same time the Moon drifts away into a more Stable orbit.
After a lot of time, the System would reach an "Nearly equal" point of Energy. But still with strong Tides.
Why is this Important ?
Because, this point where the Moon dosnt project Tidel Forces so huge on the Planet it would literally destroy Mountain Ranges and lift the Surface, takes a long time. Maybe Billions of Years if you are unlucky.
During all of this time, the Mantel will break into smaller plates. And a lot of them. So in the end, you end up with Plates very similar to the ones on earth.  Although there Composition is different and i would assume duo to the nature of the Impact, they would be smaller. But idk that for sure.
The End
Where this leaves us is a simple Answer. Duo to the close Moon, the still huge forces, the shi+ton of Plates and very dense Interior, you would see a lot of Volcanism.
Comment: If it has more dense elements, it probably has a lot more radioactives decaying and generating extra heat as well. Core stays nice and hot?
Comment: Good question. The ratio between "Light" and "Heavy" elements is almost bound to be very different. In the phase where the Moon Melts the Planet, the Elements would further seperate. Maybe into something like a Super Dense core with a lot of Radioactiv elements.
But tbh, with a moon this close by, you dont need a core.
Answer: Your planet is smaller than Earth, but denser.
This means the iron core is much larger, or the core contains more heavy elements.
Either of these scenarios lead to a core that retains and/or generates a lot more heat.
.
.
Volcanoes everywhere!
You might not even have plate tectonics, just a thin crust floating on the hotter mantle like pond scum. So NOT volcanoes, but rather long fissures and lava fields.
Not a very nice place to live.


Can we know the exact date of Resurrection?

Question: Wikipedia gives two possible dates for crucifixion 7 Apr 30 and 3 Apr 33: I wonder why we cannot date the event with accuracy since we know the details : full moon on 14 Nisan. It would seem quite easy , with modern knowledges and techniques, to determine on what year the first vernal full moon took place on 14 Nisan, what are the problems?
Comment: Actually the dates given in the Wikipedia article are for the Crucifixion.
Comment: But Wiki is also using the Julian Date, which is the convention for dates before the Gregorian Calendar was introduced.  In the 1st century the Gregorian date differs from the Julian by 2 days. It turns out if we use our Gregorian Calendar (not the Julian) then the Resurrection was indeed either 7th April AD 30 or 3rd April AD 33.
Comment: The Wikipedia article and the current answers to this question all assume that the Crucifixion was on a Friday. Some denominations find Wednesday a much more believable day for it, in which case the resurrection would have been just before sunset on Saturday 27th April AD 31.  See for instance my recent answer in [judaism - In Matthew 27:62, what is "the day of preparation"? - Biblical Hermeneutics Stack Exchange](https://hermeneutics.stackexchange.com/questions/58658/in-matthew-2762-what-is-the-day-of-preparation/58668#58668)
Comment: It was/is **always** full moon on 14th Nisan.  1st of each month is/was the day the appearance of first crescent moon, 14th of every month was full moon.  They followed a lunar calendar.  And 14th Nisan was always in _every year_ the first vernal full moon by definition.
Answer: It is indeed possible to calculate, within a few hours, the timings of full moons in the first century. Stochastic variations mean we cannot be more accurate.
The question asks whether we can apply the knowledge that there was a full moon on Nisan 14 to narrow down the possible years it could have been. Unfortunately this does not help. This is because Nisan like all Jewish and Islamic months only starts when the new moon is sighted. This means there is always a full moon on, or very close to, Nisan 14. We would be looking for a full moon occuring 14 days after a new moon became visible. Not a distinguishing feature.
Because the Resurrection was Sunday, and the Crucifixion believed to be Friday, this means that we are looking for a year in which the full moon was Thursday or Friday. We know there was a full moon on Thursday evening, April 6th, 30AD; and one on Friday afternoon, April 3rd, 33AD. In other years in the late twenties and early thirties the full moon was on a different weekday.
These dates are calculated according to the Roman calendar (Julian). We cannot say, with certainty, what date in the Jewish calendar, used in the first century,  was the equivalent to a Roman date. In principle these dates should have been Nissan 14. However the start of a month depended on actually seeing the crescent moon, and this depennded partly on the weather and the amount of sand in the air.
Furtermore, although the temple authorities aimed to ensure the Nisan full moon was the first full moon in Spring, there were other considerations. If there was a risk that the Nisan full moon would happen before the equinox they interposed an extra month, making Nisan later. Two other considerations were that the barley and wheat were developing. If they were not Nisan might be postponed leading to the Nisan full moon being the second full moon of Spring. This was because a barley offering was made at Passover time, and a Wheat offering at Pentecost. If the winter weather persisted later than usual Nisan might not be announced at the expected time.
We do not know the exact dates, in Roman terms, on which Passover occurred. We do know there was always a full moon on or close to Nisan 14, but that doesn't help.
The reason  AD30 and AD33 are the main candidates, rather than nearby years, is purely because the full moon was Thursday evening and Friday afternoon respectively.
Comment: Thanks, but we do know that preaching started in what is currently called 29 A.D. (15th year of Tiberius)  so, why can't we calculate how long preaching lasted to get the exact date? 30 A.D. seems too close, don't you agree?
Comment: _30 A.D. seems too close, don't you agree?_  I agree with that 100%, more if possible!
Comment: 15th year of Tiberius counting from co-regency was 26 AD.  15th year of Tiberius counting from sole reign was 29 AD, but to reconcile Luke, Dionysius, Eusebius, and Tertullian as the 12th year, then the same date of 26 AD corresponds.  Further, Luke 3:2 mentions the co-high priests.  Christ preached 3 1/2 years to 30 AD.
Answer: Catholic apologist Jimmy Akin in his 2013 blog article which he reprinted in the 2020 National Catholic Register article 7 Clues Tell Us PRECISELY When Jesus Died (the Year, Month, Day, and Hour Revealed) has a convincing algorithm that happens to agree with the two Wikipedia choices at Step #5: 7 Apr 30 and 3 Apr 33.  In Step #6 he said the A.D. 30 date is out.  That leaves us the time and date of Jesus's death to be precisely:

around 3:00 p.m on Friday, April 3, A.D. 33

Therefore, the resurrection date is Sunday, April 5, A.D. 33.
Here are the summary of the steps (see article for details):

The High Priesthood of Caiaphas: narrow to A.D. 18 to 36
The Governorship of Pontius Pilate: narrow to A.D. 26 to 36
After "the Fifteenth Year of Tiberius Caesar" (Luke 3:1-2): narrow to A.D. 29 as the earliest year of Jesus's ministry
Crucified on a Friday: narrow to a Friday between A.D. 29 and 36
A Friday at Passover: narrow to 2 candidates of all Passover between A.D. 29 and 36:

Monday, April 18, A.D. 29
Friday, April 7, A.D. 30
Tuesday, March 27, A.D. 31
Monday, April 14, A.D. 32
Friday, April 3, A.D. 33
Wednesday, March 24, A.D. 34
Tuesday, April 12, A.D. 35
Saturday, March 31, A.D. 36

John's Three Passovers require ministry to span over 2 years.  Since Jesus's ministry couldn't start until A.D. 29, A.D. 30 is out.  Narrow to April 3, A.D. 33
"The Ninth Hour" (Matt 27:45-50, Mark 15:34-37, Luke 23:44-46), narrow to 3pm Friday, April 3, A.D. 33
Comment: As I understand it, Sabbath doesn't just mean Saturday but can also refer to any of the feasts; there were many Sabbaths beyond just the weekly one.  Regarding step 4, couldn't the "day of preparation" have been prep for the Passover, which was also considered a Sabbath?  If this is the case, then Wednesday March, 24, A.D.34 is a candidate.
Comment: @MikeBorden I don't know.  But the identification of Good Friday as day of preparation for Sabbath (not Passover) seems quite prevalent (see [here](https://www.baptiststandard.com/news/faith-culture/was-friday-a-preparation-day-for-the-passover-meal/) for an example).  Curiously, here's an NT scholar [Andreas Köstenberger](https://en.wikipedia.org/wiki/Andreas_J._K%C3%B6stenberger) reaching [the same date](https://www.firstthings.com/web-exclusives/2014/04/april-3-ad-33) using similar calculation but has Nissan 15 (April 3) to start Thursday night instead of Friday night !
Comment: 3 days and nights, based on a Friday death of Jesus has always troubled me.  The accepted answer to this question is interesting:  https://hermeneutics.stackexchange.com/questions/2198/how-is-it-that-jesus-could-be-three-days-and-three-nights-in-the-heart-of-the-e
Answer: There are a couple of issues to consider as background to answering the OP with an emphatic yes.
Technically, the full moon is supposed to fall on the 15th of Nisan.  They left Egypt at night by that.  It was 24 hours of light with sunset and moonrise within minutes of each other.  But to find the full moon, you have to sight the new moon.  So, its not enough to only know the date of the full moon.

And they departed from Rameses in the first month, on the fifteenth day of the first month; on the morrow after the passover the children of Israel went out with an high hand in the sight of all the Egyptians.  Numbers 33:3
Observe the month of Abib, and keep the passover unto the LORD thy God: for in the month of Abib the LORD thy God brought thee forth out of Egypt by night.  Deut. 16:1

The other issue with the new and full moon is the time of the Spring Equinox.  Some disagree that the new moon must first appear after the Equinox, but nearly all agree that the full moon must appear after the Equinox.  So, one also has to know when that occurred.
The final issue, and there are many in this area, is the timing of the birth and life of Christ.  These things have to align with historic events, like the death of Herod or who the high priest was or how many Passovers Christ observed during His ministry, and when was He baptized.
If one puts all considerations together, one would find that the Triumphal Entry was on a Sunday the 10th when the people picked their Lamb (or King), Christ was crucified in CE 30 at age 33 1/2 on Thursday the 14th of Nisan on Passover.  He was already buried on the 15th Friday (full moon) on first day of Feast of Unleavened Bread.  He was resurrected at sunset as the Sabbath ended and the first day dawned (see Mat. 28:1-4).
Comment: "Christ was crucified [...] on Thursday" — do you have a citation for that? I've always understood (as does every church to my knowledge) that the Passover meal was Thursday. There is definitely nighttime following that meal and preceding the Crucifixion, and Christ was crucified on Friday morning (n.b. Matthew 27:1, and Matthew 27:45 suggests He was on the cross by noon). Strictly speaking, as Jews mark time, AFAIK he wasn't even *arrested* on Thursday (although *we* would call it Thursday, since we use midnight rather than sunset as the end/start of days).
Comment: @Matthew at the time, for example, the authorities said they will not arrest or crucify Jesus on the feast day (the 15th, first day feast of unleavened bread).  Did they do so anyway?  There are numerous citations and proofs of a Thursday betrayal, arrest, crucifixion..
Comment: AFAIK, no; after the Passover meal, Jesus went with his disciples to Gethsemane. As I understand things, it was night (i.e. after sunset) when Judas and the soldiers showed up, which, as Jews mark days, would make it Friday. Whether the *betrayal* is on Thursday or Friday is unclear. The *arrest* was, AFAIK, on what *we* would call Thursday, but was Friday to the Jews. The crucifixion AFAICT was Friday morning (by either accounting). (con't...)
Comment: (...con't) So, "proofs of a Thursday [...] arrest" is probably misunderstanding how Jews mark days, i.e. correct for the day not ending until midnight, but incorrect in that the *Jewish* day ended at sunset. Since AFAICT the timeline is quite clear that there is Last Supper (some time on Thursday), then evening/night in Gethsemane, then the arrest, then the trial *in the morning* (Matthew 27:1), I would be very suspicious of, and would very much like to examine, any claim that Christ was *crucified* on Thursday.
Comment: Alternatively, if you're claiming that the Last Supper was on a *Wednesday*, I'd be interested to see those sources also, because I'm not familiar with any churches that believe that. I'm quite familiar with Maundy *Thursday*. I've never heard of Maundy *Wednesday*.
Comment: I understand the traditional scenario and Jewish evening/day.  The authorities say they will not arrest or kill Christ on the feast day (first day of unleavened bread the 15th) Mt 26:5 Mk 14:2 Lev 23:6.  So, either they had totally lost control or they lied or contradicted themselves or they arrested and killed Him the day before the 15th Feast on the 14th Thursday as they had planned and said.  Last supper was on Thursday the 14th after sunset after Wednesday ended (about 8pm our Wednesday).  The Wednesday arrest/death scenario is completely impossible.
Answer: Lots of people think they know but if God had wanted us to know, there would have been sufficient detail in the text to work out unambiguously what the date of Jesus' resurrection was. Yet we are not given to know the year of his birth (let alone the month or the day) so why should anybody be surprised that we do not know the year of his resurrection (though it likely was April, whichever year it was.)
Consider how many specific, historic dates ARE given in scripture, especially in the Old Testament. Too many to list here. When we need to know an exact date, that is provided in scripture. So, what is God trying to get through to us by withholding enough detail to exactly date Jesus' birth, death and resurrection? After all, these events were the most momentous in all history. It's rather simple.
Paul warned Christians not to become enslaved to arguing about words and dates. He had explained to them the miracle of grace in becoming children of God and so being liberated from bondage, then continued:

"...how is it that you are turning back to those weak and miserable
principles? Do you wish to be enslaved by them all over again? You are
observing special days and months and seasons and years! I fear for
you, that somehow I have wasted my efforts on you" (Galatians 4:9-11).

Knowing those exact dates to do with Jesus have no bearing on anyone being saved by God's grace. It is the fact of his birth, death and resurrection that we are to focus on, not when - exactly - they happened. Yet over the centuries religious groups have set great store by producing an ecclesiastical calendar precisely to celebrate events on exact dates! And how they argue with groups that produce different dates!
Even Jesus warned us (after his resurrection) about this trap of wanting to work dates out. His disciples had asked him a specific question about the date of a truly important event they were looking forward to:

"Lord, are you at this time going to restore the kingdom to Israel?"
He said to them, "It is not for you to know the times or dates the
Father has set by his own authority" (Acts 1:6-7).

Sadly, much of the continuing debate about dates to do with Jesus is directly linked to being able to anticipate when he will return to usher in the Day of Resurrection and Judgment. Yet the Bible is clear that we are to anticipate his unexpected return as if that was going to happen today. We do not need to know any dates - we just need to have continuously demonstrated faith that, one day, he IS going to spectacularly return, catching everyone on the hop except his own.
That is why we cannot know the exact date of Jesus' resurrection, or of the Day of Resurrection and Judgment. We are not meant to know, for such knowledge would have no bearing on anybody's salvation. On the contrary, that could even detract from putting total faith in what Christ has done, because of pride of having special knowledge (gnosis), which is something else the Bible warns Christians against. What we have been given to know is what we should be getting on with, then, whenever Christ suddenly appears, we will not be caught wrapped up in matters we have been told not to get wrapped up in.
Answer: The main problem is that the Bible itself doesn't state the exact date of Jesus' resurrection from the grave.
The two main points of Biblical information about the day of Christ's Resurrection from the Grave:

Matthew 28:1 After the Sabbath, at dawn on the first day of the week, Mary Magdalene and the other Mary went to look at the tomb.
John 2:19Jesus answered, "Destroy this temple, and in three days I will raise it up again." 20"This temple took forty-six years to build, the Jews replied, "and You are going to raise it up in three days?" 21But Jesus was speaking about the temple of His body."

The Bible gives us the information that God wanted us to know in order to believe.  We know that Jesus rose on the first day of the week, and that he was in the earth for 3 days.
Any attempt to settle the exact day that Jesus arose would have to use information outside of biblical context and therefore unable to confirm.  So to answer your question, while information you quote could raise supposition, it can never affirm without Biblical context.
thank you
Mel
Comment: Christ died sometime in the afternoon of what would have been Friday to the Jews, i.e. before sunset. We can probably suppose He would have been in the tomb by sunset as well, since no work shall be done on the Sabbath. Let's be generous and call it early afternoon. He had Risen by Sunday, "very early in the morning" (Luke 24:1). Again, being generous, let's say this was six hours earlier than He was buried. This means He was actually *in* the tomb ("the earth") for maybe 1¾ days (not 3), which is why some churches can have Good Friday and Easter Vigil services only about 24 hours apart.
Comment: Why are you unable to confirm facts that rely on extra-biblical information?
Answer: What must be understood is that Nisan is always determined by the spring equinox: in other words 14th and 15th Nisan is always the first full moon after the spring equinox in every year, by definition.
At least, nearly always: one problem is we do not know for sure if this rule applied in the Jewish Calendar of the first century.  Do we know for sure if it was the 1st of Nisan or merely the 14th of Nisan which had to be after the spring equinox?  From the work of Anatolius, Bishop of Laodicea in Syria, called "Canons of the Passover", written about AD 270:-

'This rule [that the Passover must fall after the spring equinox] .. was known to the Jews long ago.. as witnessed by Philo, Josephus and Musaeus .. they say that .. all alike sacrifice the Passover after the vernal equinox, in the middle of the first month.' (Colin Humphreys, "The Mystery of the Last Supper", note 21 on page 210).

There are only two years when the day of preparation of the Passover, 14th Nisan, could have been a Friday (always at full moon): A.D. 30 or 33.  If you think the crucifixion happened on a Friday these are the only possible years.
There are (at least) three passovers in John's Gospel, at 2:13, 6:4, and the final one 11:55 to the end of gospel.
And "Jesus began to be about 30 years old" when he began his ministry (Luke 3:23).  Most believers suppose this means within a few months of 30 years old, not years.
A critical factor influencing when we believe he was crucified is thus the year we believe he was born.  If you think he was born about 5 BC, then you choose AD 30.  If you think he was born late in 2 BC then you choose AD 33.
The year we believe he was born is largely determined by the year we believe Herod the Great died.  And the year of Herod's death is largely determined by our interpretation of the data in the writings of the first century historian, Josephus.
For an examination of the data in Josephus see "Elapsed time for Herod the Great in Josephus" by Andrew Steinmann and Rodger C Young here http://www.rcyoung.org/articles/ElapsedTimes.pdf
Personally, I think the fact John the Baptist's ministry began in the 15th of Tiberius rules out AD 30 as a possibility.  The only way AD 30 could come back into the reaconing is if 1. Tiberius Caesar had a co-regency.. historians are very divided on this (certainly Tiberius dates his reign on coins from his sole reign), and 2. Luke in Luke 3:1 dates the reign of Tiberius from the beginning of his co-regency (very unlikely/unprecedented).
Comment: Luke 3:2 mentions a co-high-priesthood.  Most scholars date Luke's 15th year of Tiberius from the co-regency.  Tertullian, however, dates Jesus' ministry to Tiberius' 12th year, which is marked from the first full year of his sole reign.
Comment: @SLM - It is because they feel compelled to because they are convinced Jesus was born 5 BC.  It would not otherwise be considered an option.  I'm also told Tiberias co-regency began the same year as his sole reign, it doesn't add a significant number of years.
Comment: Augustus/Tiberius co-regency began 12AD, then Augustus dies 14AD.  Sole reign of Tiberius begins 15AD.  This aligns to the historic evidence.
Comment: @SLM - "This aligns" - don't think so.  If he was co-regent when AC died then there would have been no need to try to persuade T to be Emperor.. he would have been already.  There would have been no comment that T made more effort to stop being emperor than many a man would spend trying to become emperor, nor the comment that some men promise but do not deliver but that Tiberius delivers but does not promise.. (He was effectively ruling the moment AC died, but would not agree to become emperor for several weeks.)
Comment: Here's another comment.  https://history.stackexchange.com/questions/37567/is-there-any-historical-evidence-for-a-co-regency-of-tiberius-and-augustus


Saving a rendered picture with selected Buffer?

Question: I was told that when you have a rendered picture and then save it, it would be saved the way it is shown in the uv/image editor. What i mean by that are the several buffers (color and alpha, color, alpha, z-buffer). Unfortunately when im saving my pictures the buffer i selected is not being respected and i always get the same picture no matter which buffer i used. Does anybody know what could be wrong?
Answer: Nope, saving the image from the Image Editor will save the "Color and Alpha" channel no matter what channel is selected.
If you want to save one of the other passes you will have to use the compositor.
The Render Layers node is the output of what blender rendered (there are lots of passes you have access to).
The Composite node will be what is displayed in the Image Editor as the Render Result.

With the two nodes connected like in the image above (Render Layers Image output to the Image input of the Composite node) you will get the exact same thing as what you could save before.

However taking the Alpha out of the Render Layers node will give you a grayscale image of just the alpha. (In most cases there is no reason to do this because if you are saving to an image that supports transparency then the alpha channel is the same as the output here.)

Now the last option in the image editor is Z depth. If you simply take the Z and plug it in to the Image output, you will get an image that looks all white. However all the values are there, they are just over 1. (If you save to an image format the supports full floats, exr is the most common, then you will have access to all the values.) But if you are saving to a png, or just want to visualize the Z data, add a Normalize node (like in the picture). That node will compress all the values to fit between 0 and 1, which is the range that your monitor can display, and a png can hold.

Now if you want to save multiple passes all at once, you can use the File Output node.

To add outputs to the file output node open up the properties region with N then click on the large "Add Input" button.
Comment: If you save form the UV/Image editor window and choose OpenEXR as the format to save on,  you can save RGBA plus the intact Z-buffer (no need to normalize ). Moreover, you can choose not to "save as render", so you can save the Scene Referred information without applying the display transform.
Answer: another way is to use a screen shot program like Greenshot, works for me every time! as seen in this picture:

Hope i helped :)
Comment: The question is about saving the buffers along with the main image. Also there is no need to use external software to save screen grabs in blender,  just use Ctrl F3 or use the save as image option on the menu.


Stopping Cardano node... Daedalus Mainnet (5.3.0#44942bd51)

Question: I have just installed Daedalus Wallet V. 5.3.0 for the first time, in order to stake my ADA Cardano 3,800.00 tokens. I ran the 24 hour initialization synch before loading any ADA. that worked fine. then I proceeded to load my tokens: test 1 was from Coinbase of 39.00 tokens, it transferred and registered fine in the New Wallet. Then I transferred a second batch of 39.00 tokens from Binance-US to the Daedalus Wallet, that also transferred fine and showed in the wallet. Then I transferred the final large batch of Tokens from Binance 3700+ tokens to the Daedalus Wallet. That batch also showed up in the Cumulative total in the Wallet. I was getting ready to stake the tokens was checking out the Menu options, and i got a new screen:  Daedalus Mainnet (5.3.0#44942bd51)
Daedalus  Edit   View   Help
And and active Image updating over and over with a message below
Stopping Cardano node...
This process updated the databases and could take several minutes.
To preserve the data integrity, please wait until this process is complete.
then 4 symbols below: the on/off button (active), (the rest of the icons are grayed out inactive) sound icon, clock Icon, Refresh icon
MY pc is a windows 10 pro OS, with 3.7 ghz I7 CPU, 32 GB ram, and 1 Samsung NME m.2 SSD, and 1 Samsung 870 Sata SSD drive.
Windows build 44942bd51, Cardano Node 1.35.4-ebc7be471, Cardano Wallet 2023.4.14-3f9055373
This Process has been running for 16 hours so far. Do I interrupt it, as I am not familiar with Daedalus Wallet, and I don't want to corrupt or lose my tokens. I am also very new to Crypto, about 40 days now. Please advise!
Answer: Don't worry! All your transfers are already showen in the wallet, that means the transaction is confirmed. They will always stay there, As long as your seed phrase is safe, your funds are also safe. In simple term Your address is tied to your seed phrase not to deadelus.
You could restore your wallet in the Eternl app. It's fatser than daedalus


What is the size of an MC mob head?

Question: I need to know the size of a mob head in MC so I can model a mask for my modelpack. Thanks a lot if you answer.
Comment: What do mean by size? Pixel dimensions?
Answer: Mob heads are 8x8 pixels per side. However, mob heads are directly linked to the mob's texture. Therefore, to change, say, a creeper skull, you have to edit the creeper's texture. (creeper.png, under the creeper folder in entities)
Comment: Don't edit original file though, make a copy and use it via texture pack!
Comment: @AntoineHejlík He said he needs to make it for a model pack. I included the directory for the purpose of being able to put the texture under the right somewhat unusual) file directory.

What is the size of an MC mob head?


no sound on playing videos using vlc beta on nexus 4

Question: I have nexus4 . i installed vlc beta from this link as default player couldn't play all formats.while playing videos on phone, it showed only video , no audio.
video is alright.
Comment: What is 'this link'?
Comment: Plus: Did you check the videos with another player? Maybe they do not have any audio track.
Comment: after upgrade it worked all fine. thank for voting negative :(
Answer: Try another player for the device
of try the same video file in a different format if possible.
This will determin if the the video or not.
It's most likely that the vlc player doesn't support that file format as well.
Your best chance is to t another player like MX Player or BSPlayer (googled that).
Video players for mobiles are more limited on what formats they can play.
Reference/guide for you: http://www.real.com/resources/mobile-video-player


Crystal Report - Print Records at Specified Location on Page

Question: I have a crystal report that is used to print pay slips for roughly 500 employees.
Three pay slips are listed on each page and each pay slip is separated by a horizontal line which is used to determine where the pay slip should be cut in order to separate them for hand out to employees.
I would like each pay slip to be printed at a specified location on each page. I would like the first pay slip to be printed at a set location at all times and the second at a set location below the first and the third at a set location below the second so when all 170 pages are printed and stack together they can be easily cut apart on a guillotine
I am using crystal report xi
Comment: is it a pre-printed stationary
Comment: No it is not, the pay slips are printed on blank letter size pages
Answer: I think you can put a long text box as divider at the left side of the report.


Grammar: Should the sentence say, "my sister or I" or "my sister or me"?

Question: I read the following sentence, "My mother won't put up with my sister or I swearing." My question is, should the sentence say, "my sister or I" or "my sister or me"?
Comment: Take your sister out of the picture.  Which word would you use?
Answer: "I" is definitely wrong. You wouldn't say "My mother won't put up with I swearing" either. However, there are still two possible correct wordings: Either using "my" or using "me"

My mother won't put up with my sister or me swearing.

meaning she won't put up with us [when we swear].

My mother won't put up with my sister's or my swearing.

meaning she won't put up with our swearing.
The difference in meaning is negligible and mainly syntactical.
Comment: Hooray for "... my sister's or my swearing," a construction that is 100% correct and 99% underused. Although this construction is also 98% unfamiliar it hardly ever causes a ripple in conversation if the speaker's tone of voice casually treats it as 100% normal
Answer: I never heard such a sentence: My mother won't put up with my sister or I swearing. Even though it exists, since you read it, it sounds weird to me.
I think that the sentence My mother won't put up with my sister or me swearing is correct, because:

there's with in the sentence that is a preposition that doesn't support the personal pronoun I.
My sister and me are the object of the sentence.
Answer: I recommend with me. I think the general rule is prepositions such as with are followed by object pronouns ( me, you, him, her, us and them )
Answer: The correct way to say it would be me.
Consider these alternatives:

My mother won't put up with us swearing.
My mother wont' put up with we searing.

It's obvious to any native ear that we would say "with us swearing" instead of "with we swearing."  Us is used when something is an object.  We is used when something is a subject.  In this sentence, us is receiving the action of what mother won't put up with, making it an object and not a subject.
Translated into your sentence, you would also use the object me as opposed to the subject I.  So the sentence becomes:

"My mother won't put up with my sister and me swearing.


How can I make a diffuser for a 22 X 30 skylight shaft?

Question: I need to make a diffuser to an existing 22 x 30 skylight shaft. A flush mount of some kind would be my first choice. My goal is to keep heated air from going into the shaft instead of the bathroom.
Comment: This is in inches, correct? How tall is the shaft?
Comment: As an experiment, you could use the standard window heat-shrink insulation, which is attached to the edges by removable double-faced tape. 3M is the big brand, but there are off-brand versions as well.
Comment: Just thinking about warm wet air in the bathroom and, if sealed cold air above causing condensation on the diffuser. Something to think about with this project.
Answer: A standard recessed ceiling diffuser (for a 48" light) would work if you installed a divider to support the middle section for two.


Distinction between ClassObject.getClass,ClassName.class and Class.forName("ClassName")

Question: I wish to understand if both Class.forName("ClassName") and  ClassObject.getClass
return runtime instance of the class. Then why on comparing the resulting Class object obtained from the two fetches us a Boolean false(if we compare using == or equals).
    I also want to know what is the exact use of .class method called on the class name.I have read that it is determined at compile time etc but to what purpose. Won't Class.forName("ClassName") suffice??
Thanks
Comment: `Class.forName("ClassName")` attempts resolution at runtime and throw an exception if not found, while `ClassName.class` will either prevent the class from passing verification or compilation entirely.
Answer: Class.forName loads and initializes the class. obj.getClass() returns the class object loaded into permgen. If the class is loaded by the same classloader == has to return true. When you are see false for == comparison it means that they are loaded by different classloaders.
Answer: Yes, they are the same - and they return the exact same object.
Example:
public class Tryout {
    public static class A {
    }
    public static class B extends A {
    }
    public static void main(String[] args) throws Exception {
        A a = new A();
        A b = new B();
        //the same class object, one achieved statically and one dynamically.
        System.out.println(a.getClass() == A.class);
        //the same class object using forName() to get class name dynamically
        System.out.println(Class.forName("Tryout$A") == A.class);
        //different class. B is not A!
        System.out.println(b.getClass() == A.class);
    }
}

Will yield:
true
true
false

Note that the last is yielding false because - though the static type is the same, the dynamic type of B is NOT A, and thus getClass() returns B, which is the dynamic class object of b.


Eagle tstop and tcream layer values unable to change

Question: In my eagle design )I added a package from eagle lib. to my own library. I need to change the default values of tstop and tcream for this package. I was able to change the left-side tstop and tcream values and adjust accordingly. But as I tried to apply the same on the other 3 sides i am not able to do. I tried turning off the default tstop and tcream layer even that is not working. It is resetting again to 'on'.
Comment: Are there little boxes drawn inside the pads on the tPlace layer or something like that which you are accidentally clicking on when you try to change the pad settings? Could you post a picture of the part in question and which library it is in.
Comment: Doesn't answer your entire question, but to change the stop or cream for a pad/SMD you pass a point locating the part to apply the change to. For example, if you have a SMD at the origin, you would do `change stop off (0 0)`.
Answer: You change those in package definition. Select 'Information'(top left in the toolbox), click on the pad and in a window that appears uncheck 'Stop' and 'Cream'. Eagle will stop generating these two layers and you can then draw whatever you need manually.
Answer: You must increase the "Limit" value in "DRC: Masks" larger than the actual via drill value. Then, command "change stop off" will works.


How to convert 0-5v inverted serial to 0-3.3v non-inverted serial

Question: This weather stations has a 0-5v serial output.  I'm trying to read the serial output with the Adafruit 32u4 feather board and I get nonsense data out of it.  When I hook the Ultimeter up to my serial->usb cable I get the normal data output.  When I hook up the Ultimeter to a 5v arduino via SoftwareSerial in inverted mode I get proper data.  But I need to connect this weather station to a 3.3v Feather board's hardware uart which doesn't seem to be able to operate in inverted mode.  Is there a 5v -> 3.3 level converter that also will invert the serial signal ?
Comment: Please add more information to your question about the used weather station and feather board. Specifications, brand, type, links. Does that weather have a rs232 output? and the arduino is a 3.3v atmega32u4 running at 8mhz and costs 45 dollars? You need to convert the rs232 to ttl-level. The feather board might be damaged by the rs232.
Comment: I have determined that the serial output of the weather station is inverted 5v ttl.  I can get the proper data using software serial inversion.
The 5v output may be too much for the 3.3v TTL but the hardware uart doesn't seem to be damaged at this point although I can't seem to get software serial to work on the Feather board.
Comment: The rs232 can be a signal from -12v to +12v, but some devices use -5v to +5v and there are also some devices that are not very compatible that use 0v to +5v. You should use a rs232 to ttl-level converter. For a test use at least a protection resistor to the arduino. For example 4k7 or 10k. The arduino serial is idle high and the rs232 is idle -12v. It is indeed inverted as you already noticed. You can try a transistor to invert the signal. There is no need to use SoftwareSerial. The SoftwareSerial has limitations for the atmega32u4/Leonardo https://www.arduino.cc/en/Reference/SoftwareSerial
Answer: I think you're looking for an inverting amplifier. This can be done with either a BJT or a MOSFET (assuming your input is enough to turn the MOSFET on). Here's an example with a BJT:

simulate this circuit – Schematic created using CircuitLab
The output range is independent of the input and is defined by the supply voltage.
Answer: Base > Collector is not good ,for NPN transistor.
Because "Base -> collecter" is PN.
So use LM393 for level convert.
LM393 is open collecter.
Answer: I ended up using a simple voltage divider to reduce the 5v to 3v and used SoftwareSerial to read the inverted serial. Thanks everyone.