/sci/ - Science & Math

>>5817308
SR is pretty trivial.

Special relativity by itself isn't much. It only takes about a week to learn (or just a couple of days if you work hard enough).

So far quantum theory, the standard model, string theory, etc. have all been consistent with SR. You can't really find out more about SR unless there's some kind of problem in SR that needs to be solved. Maybe a problem will be realized in the future, but I dunno.

>>5817363

SR is anything BUT trivial. Just because you learned some basic formulas that work doesn't mean there were people who had to mathematically solve it all for you

Go ahead and try to derive the Lorentz transformations from scratch, and then continue on to find relativistic acceleration, velocity, momentum, etc from those transformations. Without checking online to see how they are derived. Somehow I don't think you would be able to get there

>>5817419
pretty sure he meant trivial in the same way that calculus is trivial

how's that superiority complex working out for ya by the way?

>>5817419
its all basic trig based on 1 assumption.

>>5817460

2 assumptions

>>5817375

quantum entanglement ; pls study that

>>5817419
>he cant derive the Lorentz transformations

>>5817536
Already consistent with SR.

>>5817546
ya but how can you have two atoms separated by millions of miles affect each other's spins. even faster than the speed of light ?

>asking research questions to high schoolers and undergrads

>>5817571
They don't, you just have a pop science understanding of physics.

>>5817604

and yet they would remain entangled, even at that distance. It's a Mystery.

>>5817571
SR doesn't imply that you can't. You would only get paradoxes if you had a way to use it for communication.

>>5817538
That's what she implied, hun, but why are you calling >>5817363 a boy?

>>5817614
BAZINGA!

>>5818015
>big bang theory
>le
>WoW
could you make yourself look any more autistic?

>>5818017

>>5817419
jesus christ
>Go ahead and try to derive the Lorentz transformations from scratch, and then continue on to find relativistic acceleration, velocity, momentum, etc from those transformations
why would I do this when

a) any decent textbook covers the derivations much better and more thoroughly than I ever could myself and offers more insight anyway
b) the point of science is that you build off of what other people did. Yes, everyone should at least see a derivation of the Lorentz transform, but the end results are nice and IMO fairly straightforward
c) the Lorentz transform, and all of physics really, was initially motivated by experimental data, and to "really" derive the equations you'd have to start from there

if you derive everything from scratch I honestly can't see how you have time to learn anything

>>5818017
thats from warcraft 3, not WoW. faggot

We haven't yet figured out how to time travel in special relativity. Einstein says it's possible but we don't know how.

>>5821212
Let me clarify. Einstein says time and space are the same thing. Therefore space travel implies time travel.

>>5822115
>space travel implies time travel

http://en.wikipedia.org/wiki/Minkowski_space

>>5822128
Are you confirming or refuting my point?

>>5821212
>>5822115
>time travel
>implying going back in time
>do you even causality

>I will never be able to go back in time and meet Caesar
;_;

>>5823260
Causality is nothing more than a human made explanation for the observation of correlation. Causality is a logical construct, not a natural one.

>>5823264
Who are you quoting?

Have we figured out SR in more than 4 dimensions?

Yes.

>>5828782
an enlightening response
2 a day shit bumper is back

>>5817419
>Go ahead and try to derive the Lorentz transformations from scratch, and then continue on to find relativistic acceleration, velocity, momentum, etc from those transformations. Without checking online to see how they are derived. Somehow I don't think you would be able to get there

This is piss easy. I thought this was the first problem set of every course on General Relativity. Apparently you go to a shit university.

>>5828787
This.

Anyone who learned SR should be able to do it.

>>5817419
Can't you just draw a triangle or something?

>>5830056
the derivations you learn in your first year is not rigorous if that is what you are meaning. if you understand tensor algebra then with some help you could probably do it. most people think you just manipulate expressions which is most people in this thread claiming that they could derive it.

>>5827874
yes, SR (and GR) works the same way in any dimensionality with some special things happening mostly in lower dimensions like dimensions 1,2 (quite trivial), 3 (gravity is topological, no local degrees of freedom, which is a bit cool and simpler than dim > 3). In higher dimensions, its just more complicated field theories that people sometimes study. SR is kind of trivial in all dimensions though.

>>5831952
Does it work with more than one time dimension?

>>5832466
The theory becomes spooky with temporal dimension >= 2.

>>5831528
You can derive it without tensor algebra. Zeeman's theorem gives you that the group of causal automorphisms (bijections on spacetime which map light cones to light cones) is exactly the Lorentz group, and from there it's an easy jump to getting the velocity dependence right.

>>5833142
>Zeeman's theorem

Never heard of it. What does it state?

>>5817460
>>5817530

Noob here. What assumptions?

>>5834249
That causal automorphisms generate the Lorentz group.

Here's a related paper with citations. (They all seem to be behind paywalls, sorry.)
http://arxiv.org/abs/1111.1613v1

>>5833142
>(bijections on spacetime which map light cones to light cones) is exactly the Lorentz group
What about x -> ax?

>>5834287
My bad. I meant: Lorentz group + dilations + transations. (But the latter two categories are just change of units so I forgot to consider them.)

>>5818036
Lorentz transformations were not motivated by experimental data.
His point is pretty clear also, just because you can look it up doesn't mean it is trivial. SR is complicated, it goes far beyond the Lorentz transformations.

>>5834294
>Lorentz transformations were not motivated by experimental data.
Surely you are avin a giggle.
http://en.wikipedia.org/wiki/Michelson%E2%80%93Morley_experiment

>>5833142
It is also nice that you are able to reconstruct the metric from this causal structure up to a scale factor. Perhaps a neat method of teaching the transition to some of the simple concepts of GR - for conformally trivial space-times, at least.

>>5834306
How does Michelson-Morley imply Lorentz transformations? I thought it only disproved aether?

>>5817308

>>5818015
What does that mean?

>>5837127
troll harder

>>5834294
>SR is complicated, it goes far beyond the Lorentz transformations.

Actually everything in SR can be derived from knowing the Lorentz transformations.

>>5837138
I do not know what that means, either.

How does special relativity follow from general relativity?

>>5841172
GR is SR + gravity fields, in the absence of gravity they give the same results

>>5838256
just to be perfectly clear the lorentz transformation is a contextual recomply with shit right? Notation & all that & w/e else

>>5831045
How would that help?

>>5842078
Lorentz transformations can be derived from a triangle.

>>5842078
>>5843361
It looks like pic related. Guess where the Lorentz factor comes from. Pythagoras.

>>5817455
>pretty sure he meant trivial in the same way that calculus is trivial

Calculus isn't trivial at all.

>>5844559
I love Pythagoras.

If pythagorean theorem doesn't hold anymore in non-euclidean space-time, then how can SR be derived from it?

>>5845576

how do people like this exist

>>5845576
thatsthejoke.jpg

Twin Paradox, still not resolved. If it were, they wouldn't call it a paradox. You can't explain that.

>>5848798
http://en.wikipedia.org/wiki/Twin_paradox#Resolution_of_the_paradox_in_special_relativity

According to Wikipedia it is, although it doesn't seem to address the point of the thought experiment; if they're both traveling at very high speeds away from the other, why does only one experience time dilation?

>>5848818
Only one of the twins is accellerated with respect to the other.

>>5848329
Don't be so arrogant. I bet you haven't even taken calculus yet. It's harder than you think.

>>5850396
Why is it so hard?

>>5851210
Because it's very abstract math with letters instead of numbers.

>>5852941
How are you able to do mathematics with letters?

>>5853625
I am not and I don't know. That's why it's so difficult.

>>5841193
Nope, except in lower dimensions.

>>5855037
How many dimensions is "lower dimensions"?

>>5841193
>GR is SR + gravity fields
This is utterly idiotic and completely untrue.

>>5836441
It doesn't even disprove aether, only the shit versions from before we had the Lorentz transforms.

Protip: you can derive the Lorentz transforms from ether theory, and you end up with something which is <span class="math">empirically[/spoiler] equivalent to normal SR, and one of the things you end up deriving is that you always <span class="math">measure[/spoiler] a constant speed of light. It's kinda interesting, look it up.

>>5855736
>empirically equivalent to normal SR
Not at all. There are new friction forces that try to align particles with non-zero velocity to the preferred frame.

>>5855753
I'm gonna have to ask for source on that, mate.

>>5855759
A source on what? A trivial calculation in statistical mechanics? Why do you not go to the school to learn that?

>>5855767
If it's so trivial, how about you show me? I have several textbooks detailing the Lorentzian SR approach and there are no "new friction forces" in any of those.

>>5855773
>If it's so trivial, how about you show me?
The proof is left as an exercise for the reader.
>I have several textbooks detailing the Lorentzian SR approach
You read demagogic, schizophrenic ramblings of insane crackpots and expect truthfulness?

>>5817419
>and then continue on to find relativistic acceleration, velocity, momentum, etc from those transformations. Without checking online to see how they are derived.

Velocity is just velocity
Momentum can be defined multiple different way so you need to pick one.
If by acceleration you mean force then that too has several definitions and is made by convention.

>>5855776
>does not demonstrate any substance behind his claims
Yeah, no, I'm not sure why you think anyone should take your point seriously.

Explain to me from what these "frictional forces" are said to come, otherwise I'm gonna go with my gut and continue to assume that since you just threw out the phrase "statistical mechanics" you're just bullshitting.

>>5855788
Do you not know what entropy is? How old are you?

>>5855791
>entropy has fuck all to do with your supposed "frictional forces" which relax matter back to the preferred frame
What the fuck are you smoking?

>>5855793
>>entropy has fuck all to do
Are you 12? Do you have a psychiatric illness?

>>5855753
Bullshit detected.

>>5855805
What is that supposed to show? How you are unable to find the expression for an ensemble of relativistic particles with and without a preferred frame?

>>5855809
If it's so easy, fucking post it. Don't just sit here spouting
>you're just stupid, I don't have to show anything, I can claim whatever I like

>>5855813
I am not doing your homework.

>>5855776
>ramblings
Oh, so David Bohm and John Bell are insane crackpots, then? top kek

>>5855822
The quality of posts is extremely important to this community. Contributors are encouraged to provide high-quality images and informative comments.

>>5855823
>argumentum ad auctoritatem
Way to objectively demonstrate that you are indeed twelve. Yes, they are - and not only for the aforementioned reason.
>>5855825
>>>/global/rules/3
>>>/sci/rules/2

>>5855830
>claims that some particular physical effect applies in one theory and not the other
>"Go on, what is it then? Tell me where I can read about this so we can discuss this further like adults."
>I'M NOT DOING YOUR HOMEWORK FOR YOU WHAT ARE YOU TWELVE
0/10 shoddy ruse

>>5855832
It is unfortunate that you are too much of an mentally defective toddler to do an undergraduate, freshman level exercise in statistical mechanics with physicist-tier rigor. I cannot expect you to understand the argument if you lack the intellectual facilities to deduce it yourself.

>>5855835
Stop talking out your ass. There's nothing in Einsteinian or Lorentzian relativity that says anything about particles experiencing 'friction' against the ether frame. The final form of the Lorentz transformations you get in either case is exactly the same. See:
J.S.Bell - Speakable and Unspeakable in Quantum Mechanics
D.Bohm - The Special Relativity
https://en.wikipedia.org/wiki/History_of_Lorentz_transformations#Poincar.C3.A9_.281900.2C_1905.29
Poincaré, Henri (1905), "On the Dynamics of the Electron"

How about you actually demonstrate some evidence rather than hurling insults at me?

>>5855844
None of those pseudoscience/outdated works are related to my post.
>How about you actually demonstrate some evidence rather than hurling insults at me?
How about you do your homework alone? I already gave you precise instructions.

>>5855856
>pseudoscience
I chuckled.
>outdated
Burden's on <span class="math">you[/spoiler] to show us all why those are wrong, since those have already argued their case in their text.
>homework
lol, no, this just you claiming something you pulled out your ass, and getting bitchy when we're calling out on it asking for evidence
>precise instructions
"the expression for an ensemble of relativistic particles with and without a preferred frame"
"The" expression for what, exactly? 0/10 instruction quality

>>5855862
>I chuckled.
Did you drop out of high school?
>Burden's on you to show us all why those are wrong
I do not have the time to write that out for you.
>evidence
Your cognitive impairments have nothing to do with evidence.
>"The" expression for what, exactly?
Your reading comprehension had dropped below the level of a primary school English lesson.

>>5855867
>point-dodging and insults

>>5855776
>The proof is left as an exercise for the reader.
You only say that because you know you couldn't show it yourself.

>>5855805
All I see in that screenshot is your lack of google skills.

>>5857031
Well, I don't see you showing the search terms that find the right thing. All I have to go on is a "new friction" in Lorentz Ether theory which is not mentioned in any sources I've ever seen on the subject.

>>5855753
Are you confusing undetectable preferred frames with Le Sage gravitation?

>>5857759
>Le Sage gravitation
I'm the LET guy, and reading the wiki article on Le Sage does make me think it's what the other guy was talking about. Hopefully he'll come back to the thread.

Obligatory:
>le sage
>>>/reddit/

>>5855869
>unable to understand the point
>uses the term "point-dodging"
<
>>5855895
>projecting
You are not going to make me do your kindergarten homework, you decadent moron. If you are too impotent to understand such banal material, there is no hope for you; I may as well be talking to a wall, if you or that poster is so flagrantly ignorant to claim they know what special relativity is yet lack the elementary knowledge in statistical physics to see the difference between the entropy of any distribution on the phase space of a model with and without a preferred frame. Similarly, if you would like to possess some knowledge of what the Griess algebra is, it is generally a requirement that you are able to compute correlation functions in conformal field theory - a prerequisite necessary on the students' part to comprehend.
>>5857759
No, I am not. We are not discussion gravitation or that pseudo-philosophy at all. There is no such thing as an "undetectable preferred frame", btw.

>>5857988
Abstract:
The Lorentz covariant statistical physics and thermodynamics is formulated within the preferred frame approach. The transformation laws for geometrical and mechanical quantities such as volume and pressure as well as the Lorentz-invariant measure on the phase space are found using Lorentz transformation in absolute synchronization. Next, the probability density and partition function are investigated using the preferred frame approach and the transformation laws for internal energy, entropy, temperature as well as other thermodynamical potentials are established. The Lorentz covariance of basic thermodynamical relations, including Clapeyron's equation and Maxwell's relations is shown. Finally, the relation of presented approach to the previous approaches to relativistic thermodynamics is briefly discussed.

>>5857953
>difference between the entropy of any distribution on the phase space of a model with and without a preferred frame
But that's wrong. All the thermodynamic relations are still Lorentz-covariant even in a preferred-frame approach.
http://arxiv.org/pdf/cond-mat/0102170v2.pdf

>>5857988
>All the thermodynamic relations are still Lorentz-covariant
What does this have to do with the entropy of a system with and without a preferred frame? Spoiler: nothing.

>>5817308
No, not really.

\thread

>>5857998
>entropy is not involved in thermodynamic relations
top lel
Also "systems" don't have preferred frames, the idea is that the universe does.

>>5858000
Do you have any fucking idea what you are talking about? At all? Did you fail physics 101? This is breathtakingly pathetic. After skimming through the paper - every observer will have the same expression for Boltzmann's formula, that is invariant under Lorentz transformations, so what? This has fuck-all to do with what microstates or volume of phase space they see, i.e. nothing to do with my original argument.
>Also "systems" don't have preferred frames, the idea is that the universe does.
The universe is by definition a physical system.

>>5858008
How will they 'see' different microstates or phase-space volume if the Lorentz transformations hold? Do you even understand what it means to be Lorentz-covariant?

>>5858000
Why does the universe have preferred frames? Doesn't relativity say the opposite?

>>5859539
Well, you can't exactly conclude it either way, since they give the same testable predictions. Read Bell's book. Pic related, an excerpt from the relevant chapter, chapter 9.

https://dl.dropboxusercontent.com/u/3219541/%5BBell%2C%201987%5D%20Speakable%20and%20Unspeakable.pdf

>>5858010
>they 'see' different
>different
Where did I ever claim this? Do you have some severe reading problem or brain disorder? It seems completely unbelievable to see such a reply of yours under a post which agrees with you that the Boltzmann entropy, etc. are covariant and you still get what I am arguing upside down. And I guess that your next comment will still pretend that you believe I am referring to something else. How should I scream how complete an idiot and bigot you are so that you will kindly notice that I am not talking about the faked Lorentz covariance of some formulae to calculate thermodynamical variables in a model with a preferred frame (which would have no relation to the introduction of friction forces at all unless the formulae were modified)? I will once again try to ask you: what do they see in the first place? What is the difference between the expression for the entropy of a collection of particles in a background with and without a preferred frame?
>Do you even understand what it means to be Lorentz-covariant?
I do - do you?
>>5859694
>since they give the same testable predictions
Wrong.

>>5860753
>insults
right, whatever

>faked Lorentz covariance
You keep saying things as if you're God, but not once have you justified anything you've said.

>would have no relation to the "friction forces" unless the formulae were modified
Exactly; and since the formulae aren't modified this is why you're wrong, unless you start presenting some substance rather than simply repeatedly claiming that you're correct /over/ and /over/

>what is the difference between the entropy of a collection of particles with and without a preferred frame
http://arxiv.org/pdf/cond-mat/0102170v2.pdf , again. There is no difference.
<span class="math">S = -\sum{\rho_i ln(\rho_i)}[/spoiler] and independent of whether there's a preferred frame, you get frame-independence of entropy, i.e. <span class="math">S = S^\prime[/spoiler].

>Wrong.
/Again/, you keep <span class="math">saying[/spoiler] things as if you're the utmost unquestionable authority on the matter, but offer no reasoning or justification whatsoever.

Why are you being so incredibly abrasive and insistent, and yet offer no justification whatsoever to back-up your claims other than insults and repetition?

>>5817375
>Special relativity by itself isn't much.

If it isn't much, then why are there entire books about the topic?

>>5860872
Why do you link to thermodynamics when we're talking about relatitivty?

>>5862942
Because the guy I was arguing with was talking about entropy (somehow) measurably changing relativistically dependent on whether your framework involves a preferred (Lorentzian) frame.

>>5862947
neither of you know what you're talking about

>>5862952
Do you know better? Please correct them. I want to learn.

>>5845576
calculus is essentially just elementary algebra. it is trivial.

>>5864340
>calculus is essentially just elementary algebra. it is trivial.
wrong on so many levels. If you can only say that if you can do systems of line intergrals on complex manifolds in your sleep.

>>5864364
computationally intense doesn't make it nontrivial...

>>5864398

Actually, trivial in math doesn't mean easy, it just means something that isn't necessarily a huge result but has to be included for completeness.
For example from wiki:
empty set: the set containing no members
trivial group: the mathematical group containing only the identity element
trivial ring: a ring defined on a singleton set.

Trivial also refers to solutions to an equation that have a very simple structure, but for the sake of completeness cannot be omitted. These solutions are called the trivial solution. For example, consider the differential equation

where y = f(x) is a function whose derivative is y′. The trivial solution is
y = 0, the zero function
while a nontrivial solution is
y (x) = ex, the exponential function.

>>5860872
>whatever
Those are not insults, they are scientific observations. You would care about them, if you completed your infant education.
>You keep saying things
You do not know the definition of the word "fake"? I am sorry, I do not know how to dumb this down any further for you. As before, I might as well be talking to a wall.
>God
Go back to >>>/x/.
>since the formulae aren't modified this is why you're wrong,
This does not follow at all. Why are you so keen on posting disorganized and inconsistent flapdoodle after being explicitly told that it is extraneous? Could you please answer the question in my last post regarding your potential brain disorder(s)?
>unless you start presenting some substance
Once again I am not your tutor and I am not going to waste my time typing up the answer to a freshman physics homework exercise that you will (most likely at this point) not even understand. That is something a middle schooler can work out; a mentally healthy child who unlike you does not suffer from some kind of cortical infarct.
>repeatedly
With your low intellectual capacity in mind this conversation may have to carry over to the Poincare recurrences where I will have to repeat myself a countably infinite number of times before you are able to follow.
>0102170v2
That preprint does not at all answer any of my questions. You once again make an efficacious presentation of your never-ending reading comprehension difficulties approaching the level of profound mental retardation. My suspicions are confirmed: you are either a troll fraudster or have the mental age of a three year old.
>S = -\sum{\rho_i ln(\rho_i)}
That is the formula for Gibbs entropy, yes. It is also an invariant. How fucking fascinating! It is like I am really in middle school again. Tell me, what does this and your long list of other psychotic diatribes have to do with my posts or the thread?

>reasoning or justification
Something that is self-evidently wrong does not require any reasoning or justification unless some clarification is required by the other party. If you meant to ask something, please do it. Nobody is going to try and interpret what you want out of your pernicious junk.
>abrasive and insistent
It is not my fault you do not like the truth. Keep emotions and other animal instincts out of the science board.
>offer no justification whatsoever to back-up your claims other than insults and repetition?
Quite on the contrary. You are grossly misinterpreting my posts in a delusional manner. You should ask the psychiatrist who is paid for listening to you.
>>5862952
Is this comment designed to flaunt your ignorance, innumeracy, or a combination thereof? It is hard to tell.

>>5864340
If that's what you believe, then you clearly don't know much about calculus.

If you think special relativity is trivial, you really have no idea of it

>is there anything left to study in special relativity?
Yes, for example the usual long list of classification problems of various embedded curves and surfaces with particular properties that come along with any geometry.

>>5864863
>yet another seemingly endless ream of insults

>>5827070
God.

>>5866761
That rather sounds like a problem of math and not physics.

>>5866761
Can you give an example?

>>5837138
Not eeryone watches the big band theory anon..it's not even that funny actually so they're not missing much
>>5837127
>>5839468
It's from The Big Bang theory. Said by the character named Sheldon who is an aspie physicist