The only time they go wrong is when they both operate at once, in a narrow range around black holes or the very earliest universe.
And I guess less formally there's also the problem of complexity: condensed matter physics exists because trying to solve the standard model for a solid directly is both incredibly infeasible (think "cost of flipping bits in the calculation far extends that of all matter in the observable universe") and fails to capture the emergent phenomena in a natural way.
If no inflation, then no Big Bang, so our Visible Universe is much older.
If our Universe is much older, then life evolved multiple times already. Red stars are shallow gravity wells, so they are primary target of an expansive civilization, because it easy to enter/exit them, so they are colonized first and their light is captured fully.
Note that the 'laws' of physics are no better than normal scientific theories, scientists just had more hubris back then.
It’s a much much bigger problem if the universe significantly older than we think it is… if we were to believe the Wikipedia article on this[0], we’d only expect stars to exist at all for about 100 trillion years, but given that the distribution of hydrogen availability is likely to follow an inverse exponential decay curve of some sort, we’d probably see much lower amounts of hydrogen much earlier than that.
[0] https://en.wikipedia.org/wiki/Future_of_an_expanding_univers...
(Not a native speaker).
Most galaxies in our galaxy cluster are moving away from us because of coincidence: Shappley attractor makes accretion disk by attracting mater from Dipole Repeller void[0], so our local group of galaxies is stretched along the way. At scale of our local galaxy cluster, Doppler Shift is responsible for majority of Red Shift.
At cosmic scale, Red Shift cannot be explained by Doppler Shift alone. If we take into account gravitational waves, then at least part of Red Shift can be explained by gravitational noise: gravitational waves are slowing down light a bit, so photon loses tiny bit of energy with every such interaction, which causes major part of Red Shift at cosmic scale.
> where fresh hydrogen for stars comes from in an ancient universe,
This is though question which is hard to answer. If elementary particles are bubbles, then they are popping up because something is stretching our Universe, i.e. our Universe is inflating ... oh, fck.
> where the cosmic background radiation comes from
[If inflation theory is false, no Big Bang, and visible Universe is much older, then] Cosmic microwave background is just light from distant galaxies with large Red Shift z=1000 (light was stretched about 1000 times from galaxies in range of about 4 trillion light years).
> why the distant universe appears 'younger'...
James Webb infra-red telescope is proving that this assumption is false right now. Read the news.
It is possible and I would judge even likely that some other value is conserved; that conservation of energy can be broken doesn't mean all chaos is unleashed and the Patent Office should revoke their ban on perpetual motion machines. When it is finally worked out, we may even pick up our "energy" label and move it to this new quantity. Depends on a lot of details we don't currently know. But what we today call energy is not necessarily conserved at large scales.
Saying that the universe can't do X because it violates conservation of energy is a circular argument; the precise definition of "conservation of energy" used by physics today is derived from our belief that the universe can't do X, but we also know our beliefs are incomplete. Very good approximations. Don't quit your day job to build a perpetual motion machine. But we are not in a position yet to even claim that our description of the universe is complete and we know the exact thing being conserved.
Energy is in general only conserved locally. More precisely, the covariant derivative of the stress-energy tensor `\nabla_{\mu}T^{\mu \nu}` is zero, but this can only be put into integral form in a few special cases.
GR and QM make no predictions about cosmic inflation.
The current microscopic models don’t even attempt to explain how a molecule of water is lighter than the oxygen and two hydrogen atoms that went into making it.
Oh sure, we can wave our hands at it and invoke the mass-energy relation from GR, but this doesn’t “pop out” of the Standard Model in any sense.
This isn’t some exotic phenomena only found in deep space!
We have a long way to go before we can par ourselves on the back and claim to truly understand what’s going on.
No one disagrees, but if it were that easy to just jump straight to the final theory we would have done it long ago. For now, effective theories are all we've got.
> Oh sure, we can wave our hands at it and invoke the mass-energy relation from GR, but this doesn’t “pop out” of the Standard Model in any sense.
Yes, it does. You don't need GR for mass-energy equivalence, just special relativity. And the Standard Model is fully special-relativistic.
No one is claiming to "truly" understand anything and your cynicism is misplaced.
I could understand the atoms sharing electrons, but just want to make sure I'm understanding you correctly, because you said it's unexplained.
" The weight of a molecule of water (H2O) is the sum of the weights of the two hydrogen atoms and one oxygen atom that compose it. Here are the atomic weights of these elements:
Hydrogen (H): Approximately 1 atomic mass unit (amu) Oxygen (O): Approximately 16 amu So for a molecule of water:
2 Hydrogen atoms: 2 * 1 amu = 2 amu 1 Oxygen atom: 16 amu Adding these together gives a total of 18 amu for a molecule of water.
This means that a molecule of water has the same weight as the sum of the weights of the two hydrogen atoms and one oxygen atom that compose it, because the molecule is simply a combination of these atoms. There's no loss or gain in weight when the atoms combine to form the molecule.
However, this does not take into account the minor decrease in mass that occurs during the formation of a water molecule due to the conversion of some mass into binding energy according to Einstein's equation E=mc^2. This decrease is incredibly small and generally not considered in standard atomic weight calculations, but it does technically make the water molecule ever so slightly lighter than the sum of its constituent atoms."
I really don't see what's controversial about what I've said that's riled up people so much...
It may be stated as such, and added in to equations as an external piece of knowledge from relativity, but this is cheating a bit.
Essentially, when we state that H2O has less mass than H+H+O, what we actually mean is that H2O bends spacetime a little bit less than the three atoms individually that made it up. There's no accepted variant of QM or the Standard Model that explains this. The dynamics of spacetime curvature rearranging as the photon is emitted as the hydrogen atoms burn is not explained by modern science. This is fundamentally the "QM is incompatible with GR" issue.
My point was that it isn't just near black holes that a GR-compatible microscopic theory is relevant.
It's relevant even in the flame of a candle. It's a small effect, but it's there. The inconsistency in the theories occurs at all scales.
You're joining special relativity and quantum mechanics in ways we don't understand with this statement, which I think is your point.
That said, I don't see why this statement should seem paradoxical? Burning hydrogen in oxygen is exothermic. Before, one has oxygen and hydrogen atoms containing some mass. Afterwards, one has the same energy, just distributed between the mass of the reaction product and energy. (Energy bends space-time.) Nothing suggests energy is poofed into another dimension.
> it isn't just near black holes that a GR-compatible microscopic theory is relevant
Sure. But black holes are where we get paradoxical and potentially-conflicting predictions. If we solve that conflict, we unify the theories in an observable way.
Even in pure QM, the water molecule will have less inertia than unbonded hydrogen and oxygen atoms. This should in principle be measurable by applying a known force to the water molecule and to the three atoms, and measuring their acceleration. The difference should perfectly match the inertial difference predicted by SR and GR.
GR adds the observation that, if the water molecule has less inertia, it should also bend space-time less, and it is this bending of space time that can't be explained by QM.
Though I should add that I've had a reply to a different comment once that explained that QM is actually compatible with the flat-ish but not perfectly flat space times that GR predicts anywhere not very close to a black hole. They were claiming that in fact modern QFTs can even predict things like the gravitational lensing produced by our sun, and that they only break down when near the event horizon of a black hole.
I'm not sure this is correct. It bends spacetime less simply because it's in a lower energy state. It's correct to say that the Standard Model doesn't explain spacetime curvature, but the curvature in GR is implied by the energy which is explained.
> the minor decrease in mass that occurs during the formation of a water molecule due to the conversion of some mass into binding energy according to Einstein's equation E=mc^2
Is highly imprecise at best, and misleading at worst.
It is true that the mass of the water molecule is slightly less than that of the oxygen and hydrogen atoms combined. It is not true that this excess mass is converted into "binding energy", binding energy is negative in stable molecules. That is the binding energy measures how much energy you would have to add to break up the molecule, or conversely, how much energy is lost (as heat/light/whatever) to the environment when the molecule is formed.
The mass is lower because it has been converted into heat in the environment, not because it has been converted into binding energy.
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I would call this an instance of the language model producing convincing sounding nonsense (something that they do quite often when asked about technical stuff).
Just to be clear, that statement is very well accepted physics, and we have plenty of evidence of bounding energy changing the mass of things on the more energetic reactions (the nuclear ones). It would be incredibly surprising (in "redo all of physics" surprising) if it didn't hold for chemical reactions too, but I don't think anybody has evidence.
The chemical energy in the electron orbitals is far lower by comparison (infrared as opposed to gamma radiation).
You don't need to weigh individual atoms or molecules to take measurement!
Just to be clear, that statement is very well accepted physics, and we have plenty of evidence of bounding energy changing the mass of things on the more energetic reactions (the nuclear ones). It would be incredibly surprising (in "redo all of physics" surprising) if it didn't hold for chemical reactions too, but I don't think anybody has evidence.
Not sure I follow your direction here. Seems to be a conflation of three separate things, not necessarily compatible with each other. In classical physics mass and charge (of a particle) are different properties. One defines how particle behaves in response to forces, the other how it interacts with em fields. That's one. The other, if we go into relativistic physics, there's mass-energy equivalence (as stated by einstein)... however, charge itself isn't a form of energy, BUT charged particles can have energy associated with their electric fields that would contribute, in a sense, to the overall mass-energy of a system (which is usually ignored unless we're talking sub-atomic particles or high-energy physics). That's two. And then there's binding (not bounding) energy which represents the amount of energy required to split a system of particles into its non-interacting components (such as, in context of nuclear physics, splitting a nucleus into protons and neutrons).. or you've meant electron binding energy which represents amount of energy needed to remove an electron from an atom.. that'd be a third.
Not OP, but burning hydrogen in oxygen is exothermic. It makes intuitive sense that the energy from that reaction no longer contributes to the mass of its products.
Mass-energy equivalence, a.k.a. E=mc^2, is special relativity. It's fundamentally linked with our understanding of electromagnetism. Physics students generally learn about special relativity before they get to quantum mechanics.
This is undergraduate physics level material.
Suggest a better theory so you can pat yourself on the back then.
This is a misconception of scientific endeavour in general and of physics in particular. All models are approximations of reality. We have a theory that is consistent with experimental observations, then we make observations with which the theory is not consistent anymore and we develop a new theory that explains those new observations as well, and so on. We will never have an "exact" model, whatever that even means. But we have models that have limitations that are far beyond what's relevant for most people's life.
At many points in time, we could pat ourselves on the back. The heliocentric model. Newtons model. General Relativity. The Standard Model. All these models were important steps forward and led us to where we are today, which is absolutely astonishing. No, we don't have a full theory explaining everything, but we never will.
Your are correct that there is a (strong) conflict between general relativity and quantum field theory, and this is a major problem for theorists, but it does not pose problems for using mass-energy equivalence in quantum field theories (since it comes from SR not GR).
There are real, physical, examples where the GR/QFT conflict is more problematic. For example in quantum physics labs around the world it is possible to put things which have mass in superpositions of being in two different places. This is usually done with very small objects, but it happens. We have absolutely no idea what is happening to space-time when we do this.
...except, isn't it true that the galaxy that contains the earth wouldn't exist were it not for dark matter?
In contrast, there are phenomenon which we know standard particle physics and quantum mechanics gives the wrong answere (despite getting so much else right).
If you do not possess that curiously then so be it, but others are still motivated by it.
And then of course as there are complex emergent effects of multiparticle systems that are difficult to calculate accurately.
[1] https://en.m.wikipedia.org/wiki/Standard_Model#Construction_...
[2] https://www.preposterousuniverse.com/blog/2010/09/23/the-law...
[3] https://physics.stackexchange.com/questions/128374/evidence-....