Which law of physics will eventually be disproven?

>>9053792
The law of conservation of energy follows from the time-symmetry of the differential equations of physics.

It doesn't apply, for example, in General Relativity e.g. in big bang cosmology

The total wavefunction must be antisymmetric with respect to the interchange of all coordinates of one fermion with those of another.

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>>9053792
The second law of thermodynamics is definitely bullshit. It doesn't even hold true all the time and is just "on average."

The existence of the Universe does not contradict the law of conservation of energy because there is always as much positive energy (mass) as there is negative energy (gravity).

>>9053878
I've heard the zero energy universe theory but I didn't think gravity was officially considered a negative energy.

>>9053861
Why is reversing entropy in a closed system considered impossible then?

>>9053937
It literally isn't considered impossible technically, it's just highly unlikely. Entropy is defined in such a way that in a closed system higher entropy states always have higher probability than lower entropy states. Decreasing entropy spontaneously is always a low nonzero probability.

>>9053792
Laws don't exist for the universe to follow dumb dumb they are just ways we describe its behavior. The universe in general conserves energy. The universe isn't obligated to follow that rule, that's just something it does. It doesn't contradict anything to say that the universe began and ever since it did its been conserving energy, because energy literally only makes sense to talk about in the context of a universe existing.

>>9053792
Conservation of energy is already BTFO by relativity.

>>9053997
Is that why it's considered a current technological impossibility/why the current theorized fate is heat death?

>>9054022
How so?

>>9054027
>technological impossibility
"Beating entropy" would be like rolling a million dice and "trying" not to roll certain numbers. Maybe one time you get lucky and there is a certain number that didn't get rolled out of all 1 million, but obviously this isn't the trend and there isn't really anything you can do to fix that. It's not just technologically infeasible to reverse entropy globally, there literally isn't a way you could do it besides crossing your fingers and wishing upon a star.

>>9054027
When you try to quantify gravitational potential energy in curved spacetime, you don't get the same result in all coordinate systems.

>>9054059
Neat.
>>9054056
So why has our universe not succumb to a heat death paradox prior? A previous global entropy reverse?

>>9054074
As far as we can tell the universe began in an incredibly low entropy state and has been increasing ever since, so no paradox. High entropy/entropy increase isn't the rule, the rule is that the universe as a whole should evolve in the most probable way it can. The universe could be in a much higher entropy state than it is right now, and that kind of state is more likely, therefore entropy increases.

>>9054102
I know for the past several billion years that has been the case, but I mean in relation to conservation, the universe should be of infinite age; the increase that has been happening over the past several billion years should have happened already.

>>9054120
>universe should be of infinite age
Not true. Conservation is only meant to describe behavior, not explain it. Even if the universe required energy to begin (not a given) this would not violate any laws because our laws don't matter in a universe that doesn't exist.

>>9054130
That makes sense but seems like a total hand wave.

>>9054263
>if the universe had a beginning, there must be non conservative forces in nature because something coming from nothing is against da rules.
Yeah because that shit isn't hand waving. If you want something more rigorous, don't be starting discussions about what rules nature needed to follow in order for it to bring itself into existence. It isn't a very scientific question and you aren't going to get a scientific answer. Bottom line is they aren't called laws because the universe needs to follow them, they are laws because the universe has always and continues to follow them every time we check. They are just patterns.

>>9054320
>establish patterns but they are literally pointless ontologically because they do not count or matter then and don't ask about it
>scientific

>>9054432
Not him, but they quite obviously only matter when the universe already exists, trying to use them for whatever came before the universe is an extrapolation that assumes too much uniformitarianism

>>9054432
science explains how things work
if you want to make up some "why" that feels you inside, don't come here pretending it has anything to do with science, brainlet

>>9054516
Yes but you have to start making postulations about a metaverse to sustain your model of the universe, in that case; at least so much as other things outside of the universe stop interacting for some reason after creating it.
>>9054521
See ----------------^
>Science explains how things work
>No it won't explain this thing, brainlet, why do you care?

Because without it you don't even know how persistent the patterns inside the universe can be if you just say well obviously there's some other shit going on that can just violate the laws of physics and interact with reality at least insomuch as creating it.

>>9053792
Please learn formal arguing before you start using 'logic'.
Suppose the universe exists, and this implies that energy can be created from nothing.
All this means, that, there exists a point in time t_0, such that energy was once created from nothing. It does not necessarily imply that energy can always be created from nothing.

For you're point e, you haven't considered how this 'force' could work. Suppose there is a non-conserving force as you've described. It does not imply that the universe must suddenly arbitrarily die of heat death. Suppose the effect is so small, it would take limit of time going to infinity for the effect to take place.

Then consider g. Do we exist? Could we be in a simulation? if either of these two hold, then your argument is moot, But lets assume we do exist, and we aren't in a simulation. Then, if the universe is how I've arbitrarily described in counter to point e, then it is independent of entropy, and your point holds without invoking a negative change in entropy.

It feels like you've convinced yourself your argument makes sense, but try and think counter to what you have said, see if it holds, or if it produces a contradiction.

>>9053792
>the universe should have underwent heat death untold eons in the past and never recovered. Thus, we shouldn't exist at this time
This sounds like total bullshit.
There's no reason to rule out that we are observing the first expansion -> heat death transition of the universe

>>9053792
b. is statistics more than anything.

Imagine you have 100 coins with heads up. You randomly choose a coin and then flip it. Continuing to do this could eventually make them all end up with tails up but the chances are insanely low. Even when 99 of them are in tails theres a 1 in 200 that the last one will flip into tails as well.

The most likely state 50 tails and 50 heads will also not be stable with a 50% chance to disrupt it every time you make a new toss. after this disruption theres a 25.5% chance that it will go back to being in the most likely state but 74.5% chance to be as unlikely or even more unlikely as it currently is.

>>9054750
>you guys are just shrugging off that apparently sometimes your models don't work waaaaaa take these questions seriously waaaaa
I don't think I will take the question seriously until there is empirical support to go off of. I am sorry that it makes you so uncomfortable that we know nothing about things beyond nature. There is no empirical basis for things outside/before the universe and there is no expectation that our models hold any predictive power there. It's not likely that this will change, and whatever implications you think any of this shit has will always be a matter of speculation and it will never be a matter of science.

>>9054926
If the universe has no "beginning", it's statistically impossible we're the first transition. Also, I don't know if it's physically possible to cycle beyond heat death.

>>9054818
>All this means, that, there exists a point in time t_0, such that energy was once created from nothing. It does not necessarily imply that energy can always be created from nothing.

I thought that laws must be universal across space and time; does conservation still hold as a law if it's broken at t_0?

>>9054818
>think counter to what you have said, see if it holds, or if it produces a contradiction.
Alright.

>>9055439
>I thought laws need to be universal
>is it a law if it breaks down at t0
Laws don't need to be universal, and conservation of energy absolutely is a law even if it breaks down at t0. In general, you are attributing far too much significance to laws, but it sounds like it's because you just misunderstand the meaning of the word. A law is an observed relationship between a handful of measurable things. A law is not meant to be true everywhere, and most laws we have come up with do break down in some places. A great example is keplers laws since those are strictly speaking not true at all but they identify an observed relationship that holds so long as x y or z assumptions are valid. The fact that laws break down in places isn't significant in its own right, we expect them all to break down eventually. In this case, energy is actually more or less defined so that it is conserved in time symmetric systems. There is no empirical basis for talking about the universe at t0 so this is just speculation, but I would imagine that energy would be undefined at that point in time and any point previous. But that's the thing, there's no empirical basis. The only thing that can give weight to anything we are talking about right now is empirical observation and we don't have that.

>>9055439
>If the universe has no "beginning", it's statistically impossible we're the first transition.


Okay then...
1) It's probably not possible to cycle beyond heat death
2) We exist

Conclusion: we're in the first iteration of the universe. This implies the universe has a beginning.

Now stop navel gazing.

>>9055534
Well, now I'm just more curious.

>>9055536
Your curiosity will never be sated unless you're willing to accept some mystical answer about the origins of the universe. You could also make one up yourself, but be prepared for people to laugh at you.

Also whatever that answer is, don't post it on /sci/. Nobody cares.

>>9053861
Not on average, always. If you graph the number of microstates vs the energy of them (the macrostate), you'll see that the width of the peak with the most probably macrostates is lower than a single quantum of energy. Because of this, quantization of energy makes it impossible to traverse the barrier into the next lower entrop macrostate.

>>9053816
>It doesn't apply, for example, in General Relativity e.g. in big bang cosmology
What. Hit the Stress-Energy tensor with the covariant derivative and it disappears by construction...

>>9055772
It only disappears covariantly with the Levi-Civita connection, it does not disappear properly you stupid undergrad.

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>Implying you can Prove or Disprove anything in Science

>>9055787
How does that statement support your claim?

>>9055787
>Levi-Civita connection, it does not disappear properly you stupid undergrad.
What? What does it mean for something to disappear properly?

If you're doing GR, then you're using EFE...hit the curvature side of the EFE with a covariant derivative, do some chain rule and shit cancels out by construction...so the cov. deriv. of the stress-energy tensor disappears too?

I don't see how you're escaping this conclusion while doing GR.

>>9055810
>you can't disprove things in science
hmmmm

Hypothesis: Gravity pulls things upwards
Experiment: Drop a apple
Result: Hypothesis disproved

>>9055852
I'm the anon who posted directly above you, not the guy we're responding too. It's my understanding though that this particular combination of the Ricci quantities only vanishes identically in a torsion-free connection. There have been serious questions raised as to whether this is a legitimate restriction to make for GR. No definitive evidence has been found (at least not in local measurements - idk about big bang cosmology) suggesting that we should be using a torsion-full connection.
Perhaps that's what he means?

>>9055880
I would also like to point out that no-matter which connection you use and what exactly your Einstein field equations look like, there are going to be conserved quantities analogous to the components of the stress-energy tensor. It's inevitable from the Poincare invariance. There will always be a conserved canonical energy.

>>9055861
>implying up isn't down
direction is a spectrum, bigot

>>9055880
But energy is essentially the noether charge of time translation symmetry. Even if you relax GR to some sort of Cartan theory with torsion you're going to get a conservation of energy unless your action is time dependent

A time dependent actions seems absurd philosophically and there's no evidence for it in practice. (I mean for a model of the universe rather than some sort of open thermodynamic model or something similar)

>>9053792
low quality bait. saged.

>>9055861
What if the next time the apple does not drop?

>>9055913
I agree with you. Just trying to play devil's advocate since the other anon seems to have left.

>>9055922
The point is, all one needs to disprove a theory is a single piece of evidence.

This is essentially Karl Popper's philosophy of science: that a theory's strength lies in its readiness for disproof but its refusal to be disproved. A theory which can't be disproved makes no measurable predictions.

>>9055931
I guess we'll never know.

>>9053792
"Entropy" is subjective - it is related to the number of microstates that a macrostate permits within some system. The definition however of the macrostate can vary.

If you worship the devil, like chinks do, then from your perspective entropy is always increasing, however in reality it is always decreasing.

>>9055933
>The point is, all one needs to disprove a theory is a single piece of evidence.
I disagree with this. This is exactly the reason that experiments need to be reproducible. One singular piece of evidence has no particular impact on science. You need a set of data from independent sources in order to claim something that contradicts current knowledge.

For instance, it's far more likely that a piece of electronics wasn't working properly rather than neutrinos moving faster than light.

>>9055948
>The point is, all one needs to disprove a theory is a single piece of evidence.
This is difficult because one can always attribute this to random chance. That is the point of quantum mechanics - argue that it's all random chance, attribute any thing that contradicts your worldview to thus, and argue that its true because it fits to some degree.

>For instance, it's far more likely that a piece of electronics wasn't working properly rather than neutrinos moving faster than light.

What is your definition of "likelihood"? That which you can trick people into believing?

>>9055960
I think you dropped your tinfoil hat on the way in here.

>that's the point of quantum mechanics
That is absolutely not the point of quantum mechanics.

>>9055962
But how can you be certain of this? Isn't there a such thing as "uncertainty principle" in QM? Aren't you contradicting yourself here?

>>9055948
>This is exactly the reason that experiments need to be reproducible.
Sure but once we found the faulty cable at the LHC the "FTL" neutrinos were ignored.

By single piece of evidence I mean a experimental result which has been checked and reproduced beyond reasonable doubt. I should of stated this properly.

>>9055982
"Reasonable doubt" is still not absolute certainty.

Would it be alright if someone framed you for a murder, faked video evidence, dna results, eyewitness testimony and so forth so that to a jury there would be no "reasonable doubt" as to your guilt?

Similarly, any degree of certainty in science is still not absolute certainty and does not preclude the possibility of there being a root cause different than what is implied.

>>9055982
There are plenty of anomalous results in science that have no "faulty cable" source. We need to be careful and not overstate the importance of one (perhaps flawed) result.

>>9055968
>But how can you be certain of this? Isn't there a such thing as "uncertainty principle" in QM? Aren't you contradicting yourself here?

If you think quantum mechanics is *just* the uncertainty principle, you don't know enough about quantum mechanics. Also,
>alleging that physicists are trying to "trick people"
Fuck off, shill.

>>9056000
>If you think quantum mechanics is *just* the uncertainty principle, you don't know enough about quantum mechanics.

How can you know anything at all under a system when your electron can be anywhere at all as long as you aren't looking? What's preventing you from tunneling out into space and ending up on Mars?

>>9053792
>If energy can never be created or destroyed, the Universe simply Is and has no beginning or end in relation to time. Otherwise, the universe should have never come into existence.
Maybe. Or maybe the universe was created from the conversion of energy from some unified state into its disordered state we see now
> The universe does exist, thus energy must either be capable of being created from nothing OR a state of eternal being.
Maybe. but see above.

>>9056006
I read a book by michio kaku once. He basically said that this is theoretically possible but with such a small chance it will likely never occur in the lifetime of the univers

>>9056006
It is not my job to educate you. If you want a real answer to that question, read a book.
https://physics.stackexchange.com/questions/33215/what-is-a-good-introductory-book-on-quantum-mechanics
>>9056010
>I read a book by michio kaku once
Not a good source.

>>9056009
>maybe the universe was created from the conversion of energy from some unified state into its disordered state we see

Then it violates the second point because it's a global reduction of entropy out of nowhere.

>>9055996
>"Reasonable doubt" is still not absolute certainty.
Nothing passed cogito ergo sum is a absolute certainty.

>Would it be alright if someone framed you for a murder, faked video evidence, dna results, eyewitness testimony and so forth so that to a jury there would be no "reasonable doubt" as to your guilt?
Under those circumstances I would be convicted and perhaps set free once further evidence was found. A system which didn't convict me would be ludicrous.

>Similarly, any degree of certainty in science is still not absolute certainty and does not preclude the possibility of there being a root cause different than what is implied.
Sure but that doesn't mean we can't held things as disproven to a high level of certainty. This should be obvious.

>>9056014
I already know what QM says, what I'm trying to gather is why people think it is right.

>Not a good source.
Okay, how about the fact that [math]e^{\frac{-x^2}{a^2}}>0[/math] everywhere?

>>9056014
but hes on all the tv shows

>>9056016
>Under those circumstances I would be convicted and perhaps set free once further evidence was found. A system which didn't convict me would be ludicrous.
What if you were to get the death penalty?

>Sure but that doesn't mean we can't held things as disproven to a high level of certainty. This should be obvious.
Even 5 sigma degree of certainty still leaves a non-zero possibility it could be false.

>>9056019
>>>9039057

>>9056029
So the gaussian curve is zero at some point in x? (x can't be an imaginary number in this case)

>>9056028
>What if you were to get the death penalty?
You don't see this as an appeal to my emotions lol? I don't believe in the death penalty firstly and secondly no scientific theory has an analogous death penalty. Every theory can be resurrected if the experiment falsifying it is found to be faulty.

>Even 5 sigma degree of certainty still leaves a non-zero possibility it could be false.
Sure. Like I said, only "ergo sum" is a certainty for every individual. Everything could be a lie and we could be in the matrix...

>>9056052
>Everything could be a lie and we could be in the matrix...
Is the point of science not to prove what is true?

>>9056059
That is the point of mathematics.
The point of science is to understand the behavior of the things around us. Until rather recently, it has not been our goal to concretely define what those things are. We may not be able to, as we have nothing to compare them to.

>>9056059
No. It is to provide useful models of reality.

>>9056064
>>9056063
Ok, so we have "proven" to whatever degree of certainty that some set of rules holds true in the particle accelerator. Am I then to assume it holds true everywhere?

To say that an electron can be anywhere as long as I'm not looking sounds like some nigger is trying to steal my wallet by making it "tunnel" out of my pocket

>>9056069
Replace "everywhere" with "at all energies" and you have the main question of particle physics in the 20th century.
The answer is no. The main question these days is "what is the theory that holds true for all energies?"

>needless racism
Why? This isn't /pol/

>>9056069
No we don't "prove" anything in science. We create theories which have testable predictions, we test the predictions. The ones which hold up against experimental data we keep. The ones which don't are discarded.

The process gives us models which give good predictions. We don't aim to prove anything at all.

This is simple stuff dude. You should stick to basic stuff before trying to move onto quantum physics.

>>9056081
>This is simple stuff dude. You should stick to basic stuff before trying to move onto quantum physics.
t. This guy is right.

>Replace "everywhere" with "at all energies" and you have the main question of particle physics in the 20th century.
Position space != momentum space

>>9056081
But what is the point?

Suppose we were in 1940s Germany and we wanted to prove that Hitler is a Nazi. Ok great, I see that 6 million Jews have died, and that is enough to give me my 5 sigma degree of confidence. Now what does that prove?

>>9056096
>>>/out/
go do your homework
>>>/hm/

>>9056096
>I've been exposed as being clueless about the basic methodology of science and have a spurious wiki-skimming grasp of quantum physics so I'm just gonna shitpost about Hitler then creep back to /pol/ where I belong
bye bye :)

>>9056106
>>9056102
>using circular logic
Okey then. Seems like science isn't that different than religion after all.

>>9055852
There's only conserved energy if your solution to Einstein's equations has a timelike killing vector, not generally. For there to always be conserved energy, the stress-energy tensor should vanaish when a partial, not a covariant derivative is applied.

>>9056109
Weakest bait I've seen in some time 0/10.

>>9056111
Can you give an example of a Einsteinian manifold with no timelike killing vector field?

>>9056106
I've actually taken graduate level QFT before.

When asked why 1+2+3+4... = -1/12 in the case of the calculation of the Casimir force, the professor told me "you might not be able to really add up the energies but that's just what it is". Basically, you have to engage in double-think is what he was saying.

>>9053792
h. The "rules" of whatever pre-Universe is different than after the Universe existed

>>9056136
>I've taken courses on QFT but don't have the necessary brain power to look up methods of assigning values to infinite series
Slightly better bait. 2/10

>>9056123
De sitter space does not have an (everywhere) timelike killing vector field. That's the simplest example probably.

>>9056136
lol what fucking professor would focus on the casimir force in a QFT class? That's such a waste of time.
Also nobody believes you.

>>9056145
>For some values of s (but not others), [math]\sum_{n\to\infty}\frac{1}{n^s}[/math] equals the Riemann zeta function,
>1+2+3... equals that series with s = -1
>1+2+3... is "equal" to [math]\zeta(-1)[/math]

>fallacy of affirming the consequent

I think I understand perfectly actually.

>>9056156
Haven't done GR for 3 years now. I'm really slow. But in de Sitter space the stress-energy tensor vanishes when hit by covariant derivative because the all the curvature encoding tensors are just products of the metric tensor right? How does this not imply energy conservation? Also it's got loads of Killing vector fields (maximal amount??) so can't you just pick one of those to be timelike?

>>9056171
No, you can work out the Killing vector and while you'll find that they can be timelike for a patch, you can't have killing vector fields that are timelike over the whole space. The killing vectors encode the conserved quantities. No timelike Killing = no conserved energy.

>>9056096
>Suppose we were in 1940s Germany and we wanted to prove that Hitler is a Nazi.
Nice job getting "Nazi" and "responsible for genocide" mixed up. The two aren't synonyms, dipshit. If you were in 1940s Germany, the fact that Hitler was the leader of the Nazi party would prove that he was a Nazi by definition.

>>9056224
You're right actually...

That one is a Nazi (NSDAP and their racial ideology specifically) implies that one would murder Jews, and that Hitler would murder Jews would be what the Holocaust would be used as proof of. But that one would murder Jews doesn't mean that one is a Nazi.

Similarly, that QM is true would imply that reality is inherently uncertain, and would imply certain relations which scientific experiments would be proof of. But experimental results that agree with these relations don't prove that QM is true.

Thanks!

>>9055968
VERY poor quality bait! 0/100 :( SEE ME!!!

>>9055968
You not understanding the basic principles of QM doesn't mean that QM is wrong, it just means you don't understand it.