The h Bar

Sir Cumference

02:47

Do all inner products on $\mathbb{R}^n$ induce the same topology?

More Anonymous

07:16

@M.N.Raia Also I'd be curious about the comments of your advisor. Would you be willing to share them?

More Anonymous

07:39

@skullpetrol That obviously belongs to physics! See: quantumcomputing.stackexchange.com/questions/8611/…

Slereah

08:39

Morning

More Anonymous

Morgen :P

@skullpetrol Also here: physics.stackexchange.com/questions/510992/…

Slereah

maybe all we're seeing at all times are sourceless EM radiations

and no objects exist

More Anonymous

@Slereah No measuring something over nothing is a whole different story

Ezze

I see gravitational waves tho

More Anonymous

@Ezze There is no quantum theory of quantum gravity known to us ... One cannot talk about eigenvalues :P

Slereah

08:52

There's plenty of theories of quantum gravity

More Anonymous

@Slereah How many of them make distinctions between observables and operators?

Ezze

@Slereah Hanving plenty of theories for something is exactly the same as having no theory of said thing.

Slereah

whether or not they are correct is another matter

@MoreAnonymous All the ones based on Hilbert spaces

@Ezze We have plenty of theories of classical mechanics, too

More Anonymous

@Slereah It has an observable but I do not know which one it is - is that what your saying?

Slereah

I mean canonical quantum gravity is basically just a standard theory of quantum mechanics

it has the usual observables and operators

More Anonymous

08:55

@Slereah yes in which it is an open problem to distinguish

which from which

Novalium Company

10:39

Business Idea: TV ads personalization, so I don't get pharmacy products all the time.

Slereah

11:02

There's already ads personalization on the internet and I also hate it

Physics Meta

0

Q: Fast successive Likes and Dislikes. Is critical thinking forbidden here?

There is recently an odd reaction to my questions/answers. I see when somebody likes any, it is straightforwardly downvoted $-$ probably by somebody else. I think there is a suspicion against my activities as a critical thinker in this site, and hence, I believe there are some people of the com...

Slereah

11:33

He doesn't even know critical thinking is forbidden here

JMac

12:43

Voting to close this question is another kind of discrimination too. — Mohammad Javanshiry 12 mins ago

I'm not sure why this attitude seems so common with some users

Aaron Stevens

13:02

@JMac It is hard for me to hold me tongue with that comment haha

Sir Cumference

@JMac yeah i want to write "That's not going to save your question" but eh

Aaron Stevens

I guess its that time again for a "I got some down votes and now my feelings are hurt" meta post.

Sir Cumference

followed by a "this site badly needs reform" rant

PM 2Ring

I often find his posts difficult to understand, mostly due to the non-standard dialect of English. So it can be hard for me to tell if what he says is wrong, or I'm just misreading it. If answers like that are really unclear, I do downvote them.

Aaron Stevens

Would this be too harsh or unneeded to comment :

"The issue is that this is not a legitimate question about how the site works. You got some down votes, and instead of evaluating the quality of your answers you are deciding to just make some broad accusations that do not have any real evidence. "

PM 2Ring

13:10

OTOH, now that he's boldly declared himself to be a dissident physicist I will be reading his posts a little more critically.

Sir Cumference

@PM2Ring wow i was about to say i'm a little sympathetic but that just got thrown out the window

Aaron Stevens

@PM2Ring Yeah this meta post will definitely make me not as likely to take future answers by this user seriously

Ezze

Is a dissident physicist someone who does not understand physics?

PM 2Ring

@AaronStevens Looks ok to me.

@Ezze Take a look at his profile page.

Ezze

Cant see anything obvious

Sir Cumference

13:14

he's advertising his book

description on amazon reads

> The subject is a new theory of ether that has been developed.

a bit of a red flag

Aaron Stevens

"These concepts and examples make the book read as an argumentative dissident textbook that is suitable for bachelor students in science and engineering who want to nourish their desires to research beyond the realm of orthodoxy in frontier physics."

JMac

It seems like a more mild case of some other recent meta users; where after getting a bunch of closed questions they make a thread asking something along the lines of "Am I being downvoted/silenced because the questions I'm asking require too much critical thinking for the users of this site." when really its just due to non-mainstream/unclear questions and answers.

Aaron Stevens

@JMac Yeah... Users who make many unclear posts, get many down votes, and then conclude that the down votes are due to users who are against them and their ideas.

From Amazon profile

JMac

Yup. This OP isn't as extreme as some of the "angular momentum is wrong", or "GR is really force dilation and everyone is ignoring me" posts at least.

Aaron Stevens

"In my early years at the university, I developed a deep suspicion about the correctness of mainstream science methodology when I understood that many teachers had not been as deep as I was in analyzing some mathematical and physical problems.

Moreover, the novel scientific outcomes had never added anything of high importance or interest to my knowledge in comparison to the beautiful theory of relativity and the strange quantum mechanics developed by Einstein, Schrödinger, Heisenberg and Bohr. However, attending a three or four day-a-week university was a good excuse for me to continue my independent research without my parents' interference..."

Seems to be a common pattern of taking a few bad examples and assuming it applies to everyone

PM 2Ring

13:24

I get the feeling that these guys don't realise that their dialect of English can be hard to understand for those of us outside the Subcontinent. They communicate adequately with their colleagues in English, and probably got good marks in their English exams. I've been interacting with people of Indian extraction for around 40 years, both IRL & online, so I'm pretty used to Indian English, but I still get tripped up by it.

Aaron Stevens

@PM2Ring As a minor example, I still have to remind myself that "doubt" doesn't mean "I don't think it is true"

PM 2Ring

@AaronStevens I'm tempted to calculate his crackpot index...

JMac

@PM2Ring Almost all of my experience has been with people online, a majority probably here. I've gotten used to some aspects; but it bothers me when there seems to be a refusal to understand that its not standard English. Like I totally get that to them, there's noting wrong with how they express it; but when everyone tells you there's a problem at some point you need to stop blaming everyone else.

More Anonymous

@AaronStevens thanks for editing my question. Can I ask why are people opposed to this question so much? physics.stackexchange.com/questions/510992/…

@JMac I dunno how bad this problem is but do remember one sees the worst of someone whose been on the meta for a problem (usually) . I know I've been there :P

Aaron Stevens

@MoreAnonymous Probably because the title is a subjective, somewhat philosophical question. And because the actual question is really broad. "Can someone construct a model?" Is not a very focused question

More Anonymous

13:30

@AaronStevens It isn't when I say: "The question then becomes can one construct a non-zero (conditional) probability situation"

This is a yes or no question. Not philosophy

:/

I feel that dumb youtube video is working against me. It was only meant to give some history of the question :(

Maybe I should bold that line? - "The question then becomes can one construct a non-zero (conditional) probability situation"

Aaron Stevens

@MoreAnonymous Then your post is unclear because you have to point to different places in the post to piece together what the question is. And I just said the title makes it look like a philosophy question, which might be working against you.

More Anonymous

@AaronStevens So it's not well written basically ... sigh :/

I thought it was a wonderful question. Will I get into trouble if I delete it and repost it but worded significantly differently?

Aaron Stevens

You have even put the title question in bold on your post

More Anonymous

I feel that was the gist of it :/

PM 2Ring

@AaronStevens Another common one is "the same" to refer to something they just wrote. It's understandable, but it feels very formal and rather old-fashioned, like Charles Dickens, or earlier.

I imagine some ancient English grammar textbook, from the height of the British Raj, frozen in time, being perpetuated indefinitely...

yuvraj singh

13:34

1

Q: Does Faraday's Law take into account the induced flux?

Picture a conducting loop and a bar magnet. When the bar magnet is brought near the loop, the magnetic flux through the loop changes and induces a current in the loop to resist the change in flux. The current in the loop is generating a flux in the opposite direction, so therefore the net flux m...

electromagnetism magnetic-fields

Aaron Stevens

@MoreAnonymous I think a common theme of your posts is that you put a bunch of unfocused thoughts in your "background" section. Within this section you also sort of just throw around different questions. It is really hard to find a single, focused question. The post reads more like a "stream of consciousness" than a question.

JMac

@MoreAnonymous I generally try to be as neutral as possible when first responding to meta threads that I find bad. When I get responses back like "any negative feedback is discrimination"; I usually don't remain as neutral.

Aaron Stevens

@PM2Ring I wonder if that is the primary reason for the down votes for this user?

More Anonymous

@AaronStevens I swear I should have focused more on my language skills :/ (also part of the problem might be I use a lot of intuition when I formulate a question)

Aaron Stevens

@MoreAnonymous I don't think intuition is the problem. I think your post just lacks focus. I feel like a lot of your questions can be summarized as "I am having these thoughts, but I need more help focusing them and producing a logical conclusion." In general questions like these are not bad at all, but I would say that this site might not be the best place for those questions.

JMac

13:40

@PM2Ring I think my favourite relic is calling everyone they respect "Sir". I usually find it funny just because it seems so out of place compared to my American/Canadian English.

More Anonymous

@AaronStevens Thanks

Aaron Stevens

@JMac I'll agree with you on that one. I am not sure I will ever be comfortable with someone calling me "sir"

JMac

It's especially hilarious with John Rennie, because so many people call him Sir, and he's actually from the UK. He's basically knighted on Physics SE.

Aaron Stevens

@JMac I mean that is how I picture him in my head for sure

I might make a meta post requesting that he update his profile picture to be him in some medieval armor.

I think it would be a perfect post because it doesn't require any critical thought, which is something this site abhors apparently

JMac

@AaronStevens TBH his profile picture already screams "Sir John Rennie" to me. It really adds to the charm.

And yeah, I definitely wouldn't downvote that meta post, as long as you don't include any deep thoughts by mistake.

Aaron Stevens

13:47

@JMac Yeah, we don't want any unintentional deep thoughts that would attract discriminatory down votes

JMac

@AaronStevens Well obviously, that would oppose the mainstream dictatorship here.

Aaron Stevens

@JMac I mean that's why I use this site. The feeling of absolute authority when I vote to close a question is the only thing of worth in my life.

JMac

@AaronStevens I'm glad I'm not the only one who uses this site purely for the joy of suppressing new ideas and crippling the advancement of science.

Aaron Stevens

@JMac Along those lines, that is a view I see here sometimes. I love this site and I think it is helpful in helping others understand physics, but I am not as sure in its use for "advancing science". Yet there are those users who claim that closing their questions is hindering science

Very odd

bolbteppa

Does $\pm Q = \sqrt{G \varepsilon_0} M$ even have the right units

JMac

14:00

@AaronStevens Yeah, I've never seen the site as a good way to advance the field. It's more like a very useful tool to help get people up to speed. They might be able to advance the fields themselves; but SE just isn't the place for it.

Aaron Stevens

@JMac Nice "mainstream physics" comment haha

Novalium Company

14:21

shysics

I said, SHYSICS

ChoMedit

Is there an analogy of gamma matrices for 5(or any number $\ne 4$)-component (Lorentz Invariant) field?

Slereah

Errr what do you mean

ChoMedit

Actually, I think Rarita-Schwinger equation is for 6-component field. But well, it's completely well written in terms of gamma matrices. What am I missing?

I'm sorry. I feel I totally misunderstood this.

Maybe I want to find something gamma matrix-like thing for any representation. Gamma matrix is for (1/2,0) + (0,1/2) and.. maybe something for (1,1/2)+(1/2,1) etc.. If we just focus on 4-component field, then it will be meaningless for searching all reps.

bolbteppa

14:41

There are gamma matrices in all dimensions

Higher-dimensional gamma matrices

In mathematical physics, higher-dimensional gamma matrices generalize to arbitrary dimension the four-dimensional Gamma matrices of Dirac, which are a mainstay of relativistic quantum mechanics. They are utilized in relativistically invariant wave equations for fermions (such as spinors) in arbitrary space-time dimensions, notably in string theory and supergravity. Consider a space-time of dimension d with the flat Minkowski metric, η =∥ η a b ∥= diag...

Novalium Company

@Slereah he means shysics

Slereah

I mean you can write every rep in terms of spinor indices

So the gamma matrices for any rep are simple enough to do, if a bit tedious

although finding them for arbitrary dimension is a bit tougher, yes

ChoMedit

@Slereah Thanks. Understanding spinor indices may be clue for my question

Slereah

It helps yeah

Geroch does a nice introduction for those in springer.com/gp/book/9783642419911

ChoMedit

@bolbteppa Yep. but that's for 1+D spacetime and so.. but anyway it seens to give a hint that gamma matrices are enough to describe all reps of lorentz group for any dimenison. Thanks

Physics Meta

15:57

0

Q: About synonymous tags

While asking asking a question I noticed that there are two similar tags weak-interaction and weak-interactions which leads to question for their necessity. Should any of these be deleted? If not why?

support tags tag-synonyms

Aaron Stevens

16:59

Random physics thought: Everyone is familiar with how a rolling wheel has an instantaneous axis of rotation with where it touches the ground. However, a stationary rolling wheel's axis of rotation is about its center. But we know that a wheel rolling past us and a wheel being stationary is the same scenario viewed from different inertial reference frames

So isn't it interesting how a shift in reference frames with different horizontal velocities causes the axis of rotation to move vertically?

Novalium Company

17:11

If we somehow get the neurons a brain to fire faster and the person experiences that time passes slowly (everything around him moves and happens slowly than it did before), then time is a product of our brain. HA, in your face Einstein.

ACuriousMind

@AaronStevens Think about it like this: The (momentary) axis of rotation is through a point that's stationary. When you have the rotating wheel and shift frame horizonally, the only points with pure horizontal velocity (that therefore can become stationary through the shift) are on the vertical through the axis of rotation before the shift.

Aaron Stevens

@ACuriousMind Yes I understand it. I just think it is interesting

Novalium Company

17:30

Speed superintelligence.

Sir Cumference

17:43

@NovaliumCompany Relativity doesn't talk about the perception of time, it's that objects moving at different speeds will literally experience time slower (e.g. they will age differently as well)

So if I travel at 0.9999c for 3 seconds, then come to rest, I may find myself 100,000 years in the future with humanity long gone

Time will have passed for me at a different rate compared to the rest of Earth

Aaron Stevens

@SirCumference But why can't the Earth say the same thing? :)

Sir Cumference

17:59

@AaronStevens You mean the twin's paradox?

you'd need to take into account my acceleration

oh wait you know this, you're a grad student :P

Novalium Company

18:15

@SirCumference I'm not talking about relativity at all. I'm saying that if we increase neuron fire speed, and we start experiencing time slower, than time must be a product of our brain.

This has nothing to do with relativity nor Einstein.

Sir Cumference

oh you mentioned Einstein :P

Novalium Company

Yah, just a joke

Slereah

20:05

You have to use the

RINDLER COORDINATES

roobee

22:24

Anyone know how to recreate this?
https://www.reddit.com/r/oddlysatisfying/comments/54c9a0/this_water_stream/
I heard laminar flow nozzles and strobe lights mentioned. But most laminar flow nozzle video's I've searched although the water does look smooth it doesn't look nearly as frozen

JMac

Laminar Flow DISAMBIGUATION

►

2

You don't even need a strobe AFAIK. I found this video really cool (and very relevant)

Emilio Pisanty

23:06

0

A: Are any knot volumes known to be (ir)rational? If not, then why is the question difficult?

I asked Adams at a talk earlier this year if it's still true that we don't know the (exact) hyperbolic volume of a single knot. His answer was *yes." --Ken Perko

Knot theory is hilarious

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