44,768 reputation
2080175
bio website ellipsix.net
location Wuhan, China
age 29
visits member for 4 years, 8 months
seen 6 hours ago

I'm a postdoc doing research in high-energy particle physics. I also have a hobby interest in computer programming.

You can find me on Twitter, or check out my blog and personal website! Or you can email me at stack@ellipsix.net.

Please don't contact me through any other channel about something that should be handled through this site. If you do, I'll probably just tell you to post it here.

Any responses to moderator messages, or comments on official moderation actions here, will be ignored if sent through external channels!


12h
comment DOS behavior of Van Hove singularity in a line
Cool, that helps. Sorry, I didn't mean to imply you had to link the questions amongst each other (in case that was the impression you got).
12h
comment DOS behavior of Van Hove singularity in a line
This is better. But the links at the end don't seem to add anything; I think you could safely take them out, and it would improve the question. I suggested linking to your other questions because you said they were closely related, so I thought you'd write them in such a way that it would provide useful context to links to the other parts, but actually each of these new questions is fairly self-contained; the links seem unnecessary.
12h
comment How to get the asymptotic expression of DOS near Van Hove singularity
I've closed this as a duplicate of the new question asking about the first part, because I can't pick more than one duplicate.
12h
comment How to get the asymptotic expression of DOS near Van Hove singularity
@Ruslan I can't imagine it would catch on to three posts.
16h
comment How to get the asymptotic expression of DOS near Van Hove singularity
@Simon.Z Even if the questions are related, it's still best to post them separately. In each question you can add links to the other parts, or just to the previous part, if you prefer. (These are good questions and I would probably upvote all three of them if they were posted separately.)
18h
comment Generalization of De Rham cohomology for spinor fields
@JohnDuffield keep in mind that you don't know who is downvoting your posts. Anyway, we're looking into it.
1d
comment What happens to sound at speeds greater than mach 1?
The way this is written, at the moment, it's a really good setup that stops right before asking a good question. Questions that lay out detailed reasoning and merely ask whether it's right or not aren't very good for this site. user1179554, if you were to expand on why you think your reasoning might not be correct, I think that would help improve the question.
2d
comment Can a mouse rotating a wheel violate conservation of angular momentum?
I've deleted some off-topic comments.
Jul
1
comment Energy and momentum of a relativistic electron
Incidentally, in high-energy particle physics we do often use $p\approx E/c$ even for massive particles, when the particle's mass is so small as to be negligible compared to its kinetic energy.
Jun
30
comment Clarifying some notation, the square of a vector derivative
@lemon that should be an answer!
Jun
30
comment Problem in solving numericals involving vectors
I'm really not sure what you're asking. Could you be more specific?
Jun
30
comment Need help please
I'm curious as to why someone upvoted this
Jun
27
comment How do you know when you need to use distributions to represent charge densities?
I think the question in the edit is actually a good one: how do you recognize that you need to use distributions? I've edited the question to emphasize that aspect of it. (Naturally, without that, I would have added my close vote.) I've also deleted now-obsolete comments posted prior to the previous edit.
Jun
25
comment Is magnitude of velocity same as speed?
@TimKrul I've edited my answer accordingly. But keep in mind (for the future) that it's best not to edit extra questions into your post. Editing to clarify the questions you've already asked is fine, but when you have a new, separate question, it's best to make a separate post.
Jun
24
comment Why dont we consider force exerted by atmospheric pressure in mechanics?
Actually the right way to handle this (cc @DavidHammen) is to transcribe the problem into text, not to post a different image. Posts shouldn't contain images of text or math. I'll do it this time.
Jun
24
comment What is the radius of the event horizon?
I would actually suggest editing your comment into the answer. (Nice answer!)
Jun
22
comment Can we find actual rest mass of things on Earth
@JohnDuffield I have the same objection to the phrasing used in that answer.
Jun
22
comment Why and how does negative velocity exist?
Comments are not for extended discussion; this conversation has been moved to chat.
Jun
22
comment Travelling faster than the speed of light
I deleted a slightly inappropriate comment. diracpaul, please don't make trivial edits to your post.
Jun
22
comment Can we find actual rest mass of things on Earth
Yeah, that was really a nitpick about your comment, not a complaint about the answer. That being said, I share dmckee's objection to the phrasing you used in the answer.