Stack Exchange
log in

Vincent Thacker

 Discussion on question by Just a phys…

Imported from a comment discussion on physics.stackexchange.co...
Vincent Thacker
Feb 14 21:43
What is the difference between "conserved" and "truly conserved"?
 

 Discussion on question by user341440:…

Imported from a comment discussion on physics.stackexchange.co...
Vincent Thacker
Feb 13 17:02
@user341440 The comment by Kurt G. is not correct. The definition of scalar includes being invariant under coordinate transformations. Not all functions whose outputs are numbers are scalars, e.g. tensor components.
Vincent Thacker
Feb 13 17:02
@jensenpaull No. Tensors are always coordinate-independent. It doesn't matter whether the coordinate transformation is a Lorentz transformation or not.
Vincent Thacker
Feb 13 17:02
@user341440 What assumptions are you starting with? The covariant derivative maps tensors to tensors, so there is nothing to prove as the expression is manifestly invariant by definition.
 

 Discussion on question by Cecilia: Th…

Imported from a comment discussion on physics.stackexchange.co...
Vincent Thacker
Feb 13 16:59
@Cecilia Your text is mostly incorrect because there is no faster-than-light communication in quantum entanglement. The idea that there is FTL communication is misinformation spread by pop science.
 

 Discussion on question by Chetan pati…

Imported from a comment discussion on physics.stackexchange.co...
Vincent Thacker
Jan 30 04:41
@Chetanpatil Your post is off-topic here. Is this so difficult to understand? We don't entertain such questions. Nothing is stopping you from asking elsewhere.
Vincent Thacker
Jan 30 04:41
@Chetanpatil Please don't take us for fools. This is not what the AI output would look like if you "used it just to draft". In any case, your post is off-topic here.
 

 Discussion on question by Sassinoura …

Imported from a comment discussion on physics.stackexchange.co...
Vincent Thacker
Jan 14 16:42
@Ghoster Even after translating to English, this is a homework dump and is by no means appropriate.
 

 Discussion on question by Aidan R.S.:…

Imported from a comment discussion on physics.stackexchange.co...
Vincent Thacker
Dec 30, 2024 02:41
Can you clarify what your last two sentences mean?
 

 Discussion on question by Duta Kartve…

Imported from a comment discussion on physics.stackexchange.co...
Vincent Thacker
Dec 26, 2024 22:29
Hint: Your angular momentum is incorrect.
 

 Discussion on question by Rumbleweed:…

Imported from a comment discussion on physics.stackexchange.co...
Vincent Thacker
Nov 27, 2024 23:35
@Ghoster The user you're replying to has been promoting their own "theory of Dilating Loop Relativity" in many answers on this site, over a long time.
Vincent Thacker
Nov 27, 2024 23:35
@Rumbleweed The existence of the Planck length and time does not imply that spacetime is discrete. This is a common falsehood that probably comes from pseudoscience. See physics.stackexchange.com/q/9720/174766.
 

 The h Bar

General chat for Physics SE (physics.stackexchange.com). For M...
9
22
Vincent Thacker
Nov 14, 2024 22:09
But still it's really strange how his "delete" review was accepted after it was marked as no longer reviewable, because I don't think the no longer reviewable status has the same 15-minute grace period as the review completed status (I could be wrong about this)
Vincent Thacker
Nov 14, 2024 22:06
Anyway, it's the first time I saw something like this happen
Vincent Thacker
Nov 14, 2024 22:06
@ACuriousMind I see. I think it may be a strange thing with casting delete votes from review. I don't think a "recommend deletion" would work the same way
Vincent Thacker
Nov 14, 2024 22:03
The fix lowered the grace period to 15 minutes and upon "dequeuing", the item will be marked as "no longer reviewable" and the system will no longer accept any reviews even if the user loaded them earlier
Vincent Thacker
Nov 14, 2024 22:01
The loophole was that as long as you had the review loaded when it was active, you could submit it many months later and it will still get accepted even though it no longer has effect
Vincent Thacker
Nov 14, 2024 22:00
@ACuriousMind Interesting. But I believe that the late review loophole was closed long ago in around 2016
Vincent Thacker
Nov 14, 2024 21:57
It's either 3 delete votes or 6 total reviews in favour of deletion, whichever comes first
Vincent Thacker
Nov 14, 2024 21:56
@ACuriousMind Hmm, I think 6 total deletion reviews (recommend deletion or delete votes) automatically deletes it anyway if I'm not wrong
Vincent Thacker
Nov 14, 2024 21:55
But wait, how did it manage to accumulate 6 delete reviews, though? Doesn't 6 delete reviews automatically cause deletion and mark the flags as helpful?
Vincent Thacker
Nov 14, 2024 21:51
@ACuriousMind Oh I see, thanks
Vincent Thacker
Nov 14, 2024 21:43
It didn't get deleted even though it has negative score, not accepted and unanimous delete review
Vincent Thacker
Nov 14, 2024 21:43
Hi @ACuriousMind any idea what happened to this review? physics.stackexchange.com/review/low-quality-posts/466270
Vincent Thacker
Nov 14, 2024 18:39
@Relativisticcucumber Because the charge density is constant?
Vincent Thacker
Sep 26, 2024 21:27
So the proof of the equality of distributions is integrating over the volume containing the origin
Vincent Thacker
Sep 26, 2024 21:26
@Relativisticcucumber Distributions like the dirac delta are defined by how they act in integrals
Vincent Thacker
Sep 21, 2024 21:38
@Slereah This also applies to dependencies in programming libraries
Vincent Thacker
Sep 15, 2024 20:51
@SillyGoose Yes, same for me
Vincent Thacker
Sep 15, 2024 20:47
So the fastest way to do that is a mechanistic set of rules on how to do it
Vincent Thacker
Sep 15, 2024 20:47
It's purpose is just to teach people how to use it to do essential tasks
Vincent Thacker
Sep 15, 2024 20:47
@SillyGoose Yes, because the general education system isn't designed to turn everyone into mathematicians
Vincent Thacker
Sep 15, 2024 20:41
@imbAF Index notation doesn't "mimic" matrix multiplication; it's a way of representing matrix multiplication (and is also capable of representing much more general expressions).
Vincent Thacker
Sep 15, 2024 20:36
@imbAF Yes
Vincent Thacker
Sep 15, 2024 20:32
Because in matrix multiplication, the second index of the first matrix is contracted with the first index of the second matrix, which is again by convention taking the first index as rows and second as columns
Vincent Thacker
Sep 15, 2024 20:32
So you take the transpose in order to make it match.
Vincent Thacker
Sep 15, 2024 20:32
You are trying to make the index notation match up with the matrix multiplication notation
Vincent Thacker
Sep 15, 2024 20:31
@imbAF I mean that it is not a requirement of index notation itself.
Vincent Thacker
Sep 15, 2024 20:30
@imbAF No, this is not a requirement
Vincent Thacker
Sep 15, 2024 20:27
@imbAF Because $\Lambda^\alpha_{\;\beta} = (\Lambda^T)_\beta^{\;\alpha}$
Vincent Thacker
Sep 15, 2024 20:24
Are you aware that it currently can't really do problems like a person can?
Vincent Thacker
Sep 15, 2024 20:23
@imbAF Why would you ask ChatGPT this kind of question?
Vincent Thacker
Sep 15, 2024 10:54
@imbAF Yeah and higher ones as well
Vincent Thacker
Sep 15, 2024 10:50
Which were the terminologies I initially saw when I was learning it the first time
Vincent Thacker
Sep 15, 2024 10:49
What led me to the correct mathematical view was the absolute confusion of physicists' attempts to explain "contravariant" and "covariant" indices
Vincent Thacker
Sep 15, 2024 10:45
You can choose to write both however you wish as long as you keep track of the contractions correctly
Vincent Thacker
Sep 15, 2024 10:44
Again, it goes back to what I've said earlier - how it is written out on paper is secondary
 

 Discussion on question by To Jay: Var…

Imported from a comment discussion on physics.stackexchange.co...
Vincent Thacker
Nov 11, 2024 22:51
@ToJay Do not delete and repost closed questions. Instead, you are supposed to fix the original and submit it for review. Original question: physics.stackexchange.com/q/833702/174766
 

 Discussion on question by Robo: Does …

Imported from a comment discussion on physics.stackexchange.co...
Vincent Thacker
Oct 23, 2024 20:33
This is an extremely poor question. de Broglie's law is $\lambda=h/p$, and the equation $p=mv$ doesn't apply to photons. That's it. Every equation has a set of conditions under which it holds, and there is no reason for it to work if you violate them.
 

 Discussion on answer by Dale: How doe…

Imported from a comment discussion on physics.stackexchange.co...
Vincent Thacker
Sep 15, 2024 20:22
@YBZ98 The reason I mentioned your earlier question was because your initial attitude was terrible. Anyway, what's the issue now?