/sci/ - Science & Math

No theory in physics ever has or can be proved.

>>6973625
OP said falsifiable, not provable. Do you even Popper ?

>>6973592
String theory and multiverse theory are unfalsifiable garbage. Plebeians seem to want to believe those theories for whatever reason.
>>6973625
This is also true, no rigorous way of proving existentialism, any attempts are just some philosophical wank. Though, physics doesn't need to care about that.

Popper's depiction of science is too simple. Philosophical questions are on par with those of the sciences and theories, not statements/hypotheses are falsified, holistically. Read more Quine.

With that said, metaphysical principles are a part of any scientific theory. Einstein's thought experiments for relativity began with metaphysical thoughts, as did his wave-particle solution to the photoelectric effect (led to QM).

There are metaphysical implications in all theories of physics, but we have to look at the physical evidence to determine if a theory is successful. Of not, it shouldn't be considered to be replacing anything as of yet. Doesn't mean we shouldn't try, though, because that's how revisions happen.

>>6973592
Most modern complex physics is unfalsifiable garbage. This includes "dark energy", "dark matter", "string theory", "M-theory", and even some of Einsteins theory of general relativity. The only theory that honestly has solid concrete and rigorous mathematical proofs with no logical inconsistencies is Shrodingers equations on Quantum physics since they are derived off of spring-mass damper systems in order to model wave like behavior in 3space.

Most of physics (and I believe quantum physics as well) has been reformulated via phase-space models, which in my opinion (being a controls system engineer) is really the only way to adequately model complicated, Markovian/Lyapunov transient systems, but can be extended to everyday normal time independent systems as well. Phase space models are less complicated than Hamiltonian mechanics (math wise and intuitively) and they come up with the same answers.

>>6973721
>Phase space models are less complicated than Hamiltonian mechanics
Hamiltonian mechanics is exactly the phase space formulation.
There are geometric and algebraic ways to pass from classical phase space to quantum mechanics
http://en.wikipedia.org/wiki/Geometric_quantization
http://en.wikipedia.org/wiki/Wigner%E2%80%93Weyl_transform
but not even with string theory are there mathematical discrepancies, from an engineers point of view. It's a pretty geometric theory, may it be a valid description or not. General relativity is much less problematic still - mathematically that's just pseudo-Riemannian geometry which soon is established for 150 years as a proper mathematical discipline.

Also
>Shrodingers

>>6973688
Care to give a small TL;DR on Quine to orient my reading? I like to think I understand Popper well and I want to read on Quine.

>>6973721

I'm also not completely convinced that gravitational lensing has been proven. There are a lot of text books that like to point to a certain blurry pictures of stars and say "oh this is gravitational lensing"; I'm sorry, but a blurry picture of a star (at least for me) isn't conclusive evidence of anything. Chock it up to gases interacting with the light causing it to blur out of focus or something. When you ask people about how exactly they've proven gravitational lensing, the scientific community just says dogmatically "Oh well, you're just not mathematically equipped enough to understand the current theory" - Oh really?


http://www.scribd.com/doc/99140744/The-special-Theory-of-relativity-a-Critical-Analisys

This article was made in 1970, just imagine that- the theory of relativity is so widely misunderstood, mistranslated, mis-communicated, etc. and is so inherently complicated/convoluted that people 50 years after its inception have been struggling to accept it in its entirety. While physics books like to "hush hush" this crowd away. I personally wish I had more time to investigate physics, but unfortunately all I can do is mock how convoluted the entire formulation of einstein's equations are and hope that some day physics people take aim at the model.

>>6973733

No it's not. Phase space formulations and Hamiltonian mechanics are completely different entities; if they were the same they would have the same name.

Phase space models really didn't become remotely popularized until the 1960's when control systems issues started arising (NASA, ICBM's); and as far as science goes, it emerged out of the work of Ludwig Boltzmann, Poincaire and Gibbs but was never formulated as a "model of the physical laws"; that's new science created by Greenwold and Moyal in 1949. Again, control systems engineer here.

>>6973721
>>6973773
Are you an idiot? you dont seem to know anything about the topics you are talking about and just mashing in phisicsy sounding words.

Have you ever read a textbook on any of those field in your life?

>>6973789

Great Ad-Hominem you got there.

Not mashing in "phisicy" (whatever that means, dictionary please?) sounding words, just actually know what I'm talking about.

>>6973773
>special relativity
>inherently complicated
>complicated
You have literally got to be brain dead to think its complicated, its high-school trigonometry for fuck sakes

>>6973796
Thats not an ad-hominem you idiot, I was insulting you. Learn the bloody difference.

>>6973798

>> Thinks Ricci tensors are highschool physics.

That's pretty funny.

>>6973804

>> "I'm not insulting you to disparage you in order to make myself sound smarter by comparison, I'm insulting you to make myself sound smarter by comparison"..

Oh okay, gotcha. I apologize for the misunderstanding.

>>6973806
>Ricci tensors
>in special relativity
wat

>>6973811
No, im insulting you because i cant come over to your house and bludgeon the knowledge into your head with a physics textbook and I know debating with retards on /sci/ who think they know everything is a waste of time

>>6973740
Quine made many contributions to the philosophy of science, as well as logic, and I couldn't give him much justice here. He had interesting views on modal logic and the necessity of logical laws, but the holism being discussed is probably what he's best known for.

A scientific theory could be viewed as a list of propositions. Part of scientific inquiry is to suggest a new proposition (a hypothesis) and see if it is experimentally demonstrable. One view is that, if an experiment produces a negative result, then the hypothesis is falsified.

Quine's objection is that, logically, ANY ONE of the propositions may be false, and not necessarily the most proximal one. For instance, if a chemist is trying to elucidate a proposed reaction mechanism based on 1H NMR data, and the data fails to demonstrate it, it could be case ANY proposition of the underlying theories is wrong. Not just that specific mechanism, but perhaps some fundamental law of chemistry, or even the theories related to the electronic components of the NMR itself, or the physics behind nuclear resonance, etc. Logically, all it takes is the failure of one link in this extended chain to produce the false result. The telescoping theories on which it is based must be considered as a whole (hence we get Quinian holism).

This seems unlikely to us as older theories have proven successful in other areas, but assuming that unlikelihood could open up whole other cans of worms such as inductive risk, the Bayesian problem of priors, etc. This is a rich area of research in the philosophy of science that has been around for a while.

Wiki the Duhem-Quine thesis for a more complete picture, I know that my shoddy explanation is full of gaps but I'm writing this off-the-cuff.

>>6973832
Hmm, on second thought I'd say he's best known for his Two Dogmas paper blurring the distinction between analytic and synthetic truths (woops!)

>>6973832
Another point to add to this is that Quine rejected the notion that one may believe any conclusion "hold come what may."

For example, suppose I believe I parked my car behind the grocery store on a snowy day. I remember parking it there. My footprints lead from the car to the front door. There is security camera footage of my car parked in the spot I left it.

Now suppose someone does not believe I parked it there. I could tell them I remember doing it, but they could say my memory is foggy. I could show the footprints, they could claim it was someone else's coming from the back of the store. I could show them the video footage, and they could claim the camera is broken. I could even show them the car, and they could claim they're currently hallucinating. They could come up with a constellation of reasons to hold onto that one belief of theirs.

Each instance of rejection above involves rejecting more and more fundamental beliefs in our "web of beliefs," the theories connected in a holistic sense. Obviously there are problems with this, but it does raise interesting questions about why we think some statements are more easily falsifiable than others.

>>6973832
The third paragraph is more related to Duhem's views, but still relevant to Quine's hold come what may.

String theory is probably closer to pure mathematics at this point. I doubt any predictions unique to string theory will ever be decided in the near future unless SUSY is completely ruled out. I think it's probably true, though.

>>6973904
Where can I find the lastest scientific report ?
(high level)

>>6973908
Probably on arxiv somewhere in hep-ex. The LHC is starting again soon, so SUSY will probably be constrained even further.

>>6973811
>Oh okay, gotcha. I apologize for the misunderstanding.

>Insults
>Same as Ad Hominem

Jesus, sure is /sci/ in here.

>>6973913
>>6973813
>>6973811

Confirmed for trolling.. Isn't school supposed to be starting? Don't you guys have homework to do. If you're not going to add anything productive to this discussion please leave.

>>6973913

I thought you physics people actually understood how to read simple dictionary definitions; I know "ad hominem" is latin but it's something that you SHOULD have learned in the 4th grade.

Ad Hominem: Attacking a persons character.

Hmmmmmm...

I mean, it MUST be the same person, there is no way that this many people on /sci/ can actually be this retarded, right?

>>6973688
Can someone provide a working definition of metaphysics for the unwashed masses like me?

>>6974002

These people are just pissy because they don't know anything about Einstein's field equations concerning general relativity and they want you to know how stupid/foolish you are for actually being educated. I guess? I mean, it's really hard to understand Autistic children.

>>6974006

Metaphysics concerns itself with the philosophy of the knowable reality or finding the constituents of reality. By "finding" I mean arguing and philosophizing about realities underpinnings as people involved with metaphysics aren't necessarily following the scientific method, although their arguments usually follow some sort of logical/pseudo-logical paradigm built on top of generally unproven assumptions.

Popper is outdated. Keep up damn it.

>>6973832
I don't see how this affects Popper's postulates in any way, other than minor clarifications. Care to elaborate in this?

>>6973721
>Shrodingers equations
>equations
Can I laught yet?

>>6973721
>which in my opinion (being a controls system engineer)
Opinion discarded.

>>6973785
>if they were the same they would have the same name.
That's a silly argument.

In any case, I guess we just use the word differently..

>>6973785
>if they were the same they would have the same name.
That's a silly argument.
In any case, I guess we just use the word differently.

Also, why do you emphasis twice
>Again, control systems engineer here.
I don't see why that would make me take your point about what consistutes science, and the shortcomings of general relativity an string theory, more seriously. I'm a theoretical physicist - don't know why you feel the need to call most of "modern complex physics" garbage..

>>6974002
"Your argument is wrong because x, therefore you're a retard." is not the same as "Your argument is wrong because you're retarded, therefore x."

Please learn what ad hominem actually is before bandying it about. http://laurencetennant.com/bonds/adhominem.html

>>6974179
So, is the later the ad homonym?

>>6974201
Yes, and it's "latter".

>>6974179

I'm pretty sure he just gave you the definition of ad hominem. I'm just having trouble understanding how retarded this person actually is.

>>6973882
/pol/ and /x/ in a nutshell

>>6974179
>>You're argument is wrong because x, therefore you're retarded.

Looking back at the comments let's see.

>>6973789
>>Are you an idiot? You don't seem to know anything.

>>6974206
Yes it's the latter.


Hmmmmmm, confirmed for austist.

>>6974278

Well regardless of who's right and wrong, I really just don't see what importance he's bringing to the conversation.

>>6974179

Obviously he THINKS he's intelligent, and he THINKS he's in fact so intelligent as to make previous poster look like a retard in comparison; however he's brought nothing to the conversation but acting like an autistic child. I wish he would actually start bringing in some math/physics and enlighten us all on how the Einstein General Field equations can be taught to highschool children (which was a claim made earlier).

>>6974172

"Symplectic manifold" is then called the phase space.

Hamiltonian Mechanics, as derived by Hamilton in the early 19th century has nothing to do with phase spaces. I'm just being clear here, because honestly if you look at his writings, neither Lagrange or Hamilton had any idea of what their work could do for the control systems industry.

It's not a silly argument, if they were the same exact thing (which they aren't) , they wouldn't have books written entirely on the subject of how to interpret phase diagrams as opposed to "Hamiltonian mechanics". Hamiltonian mechanics as the name suggests is a method of calculating properties of a mechanical system, it's not entirely useful for most everyday events either which is where we would choose to use Lagrangian Mechanics instead.

>> I don't see why that would make your point

Because we use phase space formalism to solve control functions every single day.

>>Theoretical physics

Do you know the answer to why gravity would affect the acceleration of a photon if photons are massless entities? I can't find anyone who knows the answer to this question.

The article I posted here:

http://www.scribd.com/doc/99140744/The-special-Theory-of-relativity-a-Critical-Analisys

Also seems to think that there are some quirks with Einstein's ideas. Although, it didn't really offer much in the way of alternatives.

>>6974322
I think this post is the definition of what is known as "damage control".

>Do you know the answer to why gravity would affect the acceleration of a photon if photons are massless entities?

>Mass is the source of gravitation in GR

HAHAHAHAHA! But if you're being serious, it's because in GR it's momentum flux that leads to gravity not mass, as you should expect.

>>6974341

It's not damage control, it's responding to people who are obviously confused, then asking a question to see what kind of responses a theoretical physicist and a troll would provide.

>>Momentum flux leads to gravity

Wrong, it's because light possesses energy even though it has no rest mass. Gravity according to Einstein effects everything with energy, light has energy therefore gravity has an effect over it. Gravity according to Einstein isn't a vector like force but the bending of a geodesic space time, so light simply follows the geodesic. I'm glad to see you pass the test.

;P

>>6974570
>Implying the stress-energy tensor doesn't have components of energy and momentum
>Not talking about stress-energy tensor

>>6974581

But that's not what you said. If you had said the Einstein stress energy tensor gives rise to the geodesic nature of space time, which therefore gives rise to the effects of gravity on light. Since this isn't the answer you've chosen to give, because you wanted to show off how much more intelligent you were than me, you are wrong. Lol

Nice try.

>>6974605
I have no interest in getting into an argument with you over this, mainly because given what you've written and how it's written I can tell this is a subject you know very little about, for example:

>geodesic nature of space time

This doesn't make sense, space time doesn't have a "geodesic nature", since a geodesic is just a generalisation of a straight line, it's a property of the motion of test particles, not a fundamental feature of space-time. Moreover you seem to think that it's the energy content of light that causes it to be affected by gravitation, this is wrong on a fundamental level, <span class="math"> \mathbf{T} [/spoiler] causes a curvature of space time, light then follows this curvature moving along a geodesic. If you knew even the most basic part of GR you'd know that <span class="math"> \mathbf{T} [/spoiler] has components of energy density, momentum density, and momentum flux.

>>6974616

Did you not read

>>6974570

>>light simply follows the geodesic

I guess reading comprehension is pretty hard for you? :p

>>Geodesic , not a fundamental feature of space time.

Let's see according to wikipedia

>> In general relativity, gravity can be regarded as not a force but a consequence of a curved spacetime geometry where the source of curvature is the stress–energy tensor

Hmmmm, which more or less is exactly what I said above..


My point is, you are so god damn concerned with making yourself look smart. What with your less than witty comebacks and flat out trolling. I would hope that someone who's actually in upper level physics would at least behave properly in a scientific debate.

>>Since this is a subject you clearly know very little about.

I derived the Einstein equations a while ago when I thought theoretical physics looked like an interesting major, I still have a passing fancy with theoretical physics. I don't personally consider myself an expert, but I didn't start out the conversation talking down other people- simply reiterating points where there seemed to be confusion. Such as people apparently not understanding that Ricci tensors appear in G.R ERE equations (I thought all physics students knew this) or that the phase space and Hamiltonian mechanics are completely different (duh, should be obvious by just looking at Hamiltons writings). But apparently I'm the one who doesn't know anything? Clearly you're joking right?

I'm done with this debate. Go back and get a proper education since you don't have any reading comprehension

>>6974645
>Hmmmm, which more or less is exactly what I said above..

Not that guy but, that's nothing to do with what you said.

>or that the phase space and Hamiltonian mechanics are completely different

Retard alert. Retard alert.

>>6974655

Best troll ever 10/10

>>6974645
>or that the phase space and Hamiltonian mechanics are completely different (duh, should be obvious by just looking at Hamiltons writings).

It's like they might have been developed and unified at different times or something.

>>6974660

Personally in a convo like this, without in prior background in the matter at hand, I would believe the person who sounds the most sane/rational as opposed to the person who seems to be arguing for arguments sake without contributing anything meaningful to the discussion at hand.

>>6974655
>>6974616
>>6974581
>>6974341
>>6974278

Seems to just be arguing for the sake of arguing. Not on topic either.

>>6974666

>>Shows picture

Critical reading comprehension skills

"manifold cotangent bundle describes the phase space of the system"

key words -

"manifold cotangent bundle" describes (not the same as) "phase space"

It's like they didn't take a 4th grade reading class or something?

>>6973721
>Most modern complex physics is unfalsifiable garbage
Translation:
>I don't understand it, therefore it must be false

>>6974685

>>gets angry

>>Everyone who criticizes must be wrong.

Dropping physics essay showing that Einstein's "gravitational lensing" interpretation of light being bent isn't the only or best interpretation of that phenomena.

www.colutron.com/download_files/Bend.pdf

Looks like it's time to get out Ockham's Razor.

>>6974714
>Implying "Most modern complex physics is unfalsifiable garbage" is a criticism and not just a proclamation.

>have often been criticized for being weird since they are conceptually difficult and often impossible to understand.

Well that's not really a criticism, well maybe with some undergrads when they're first exposed to GR, but from actual physicists? No.

>One serious problem with Einstein’s bending of light theory is the assumption that light accelerates and falls closer to a gravitating body according to the equivalence principle

Oh god no, this is wrong on a fundamental level, in GR light travels at a constant speed, when it enters a gravitational field the direction of the velocity changes but it's magnitude doesn't change.

>thus most probably ruling out the existence of so called black holes.

It's like whoever wrote this has never heard of the Schwarzschild solution.

I'd like to see whoever wrote this shit to come up with a Newtonian explanation of time dilation. GR is currently the best description of gravitation we have.

>>6974645
>>I derived the Einstein equations a while ago

Sorry dude, calling horseshit on this. You might have read the relevant chapter in a book, but you didn't derive them from scratch.

>>6973816
this sounds like a teaching technology of the future. Patent that shit