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Dark matter is a supersolid that fills 'empty' space, strongly interacts with ordinary matter and is displaced by ordinary matter. What is referred to geometrically as curved spacetime physically exists in nature as the state of displacement of the supersolid dark matter. The state of displacement of the supersolid dark matter is gravity. The supersolid dark matter displaced by a galaxy pushes back, causing the stars…
One question I have: is it not possible that the big bang occurred an infinite time ago? If the expansion of the universe is accelerating with time, does it not indicate that, if we reverse the time, the deceleration is asymptotic? In that case the big bang is compatible with a universe that has always existed and did not have a beginning
It depends on what you mean by "the big bang". The strictly correct meaning of "the big bang" is "the hot, dense, rapidly expanding state of the universe that is the earliest state for which we have good evidence". We know that state occurred a finite time ago--about 13.7 billion years.
What we don't know for sure is what came before that state, or how far into the past whatever came before it extends. The current best theory we have is that it was some kind of inflationary epoch, but different models of inflation give different answers to the question of how far back in time that epoch extended. AFAIK the possibility that inflation extended infinitely far back in time (i.e., that there was never any "initial singularity") has not been ruled out.
One question I have: is it not possible that the big bang occurred an infinite time ago? If the expansion of the universe is accelerating with time, does it not indicate that, if we reverse the time, the deceleration is asymptotic? In that case the big bang is compatible with a universe that has always existed and did not have a beginning
The expansion is accelerating now, but from the big bang up until a few billion years ago, it wasn't; it was decelerating. So you can't just extrapolate the current acceleration back in time.
This spawned a question for me that seems like it must be nonsensical but I don’t know the answer. Why did the Big Bang not just produce a Big Hole? IOW, if all the current mass of the universe was in a small volume wouldn’t it have promptly created a black hole? I’m assuming the answer has something to do with mass not actually existing in its current form until the universe expanded enough. However I don’t have any…
The early universe was ridiculously homogeneous. We can infer this with reasonable certainty from the extreme homogeneity of the CMB and from the gravitational instability of density fluctuations: as you expect, they attract more mass and accrete to form stars and galaxies. So if you start from the universe as it looks now and run time backwards, you get ridiculous homogeneity at the bang. And that's why you didn't g…
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The early universe was ridiculously homogeneous. We can infer this with reasonable certainty from the extreme homogeneity of the CMB and from the gravitational instability of density fluctuations: as you expect, they attract more mass and accrete to form stars and galaxies. So if you start from the universe as it looks now and run time backwards, you get ridiculous homogeneity at the bang. And that's why you didn't g…
A second issue is in Time 0.0001 seconds the observable universe is only a 0.0001 light seconds radius which limits how much mass could form a black hole.
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> if all the current mass of the universe was in a small volume wouldn’t it have promptly created a black hole? No, because it was expanding too rapidly. The usual intuitions about how much mass in how small a volume it takes to make a black hole assume that the mass is stationary, or nearly so.
I like u/Retric's comment on this too: > A second issue is in Time 0.0001 seconds the observable universe is only a 0.0001 light seconds radius which limits how much mass could form a black hole. That is, if you imagine all that mass-energy springing into existence in a vast universe (but with every point much closer to each other than today), there was not enough time for all that energy to notice the gravity of the…
You can't; this violates conservation laws. In other words, there is no solution of the equations of GR that describes mass-energy springing into existence in a universe that was empty up to that point.
At the end of inflation, matter and radiation in the form we know them today (the quantum fields described by the Standard Model of particle physics) got a huge amount of energy pumped into them; but that energy did not come from nowhere. It came from the inflaton field--the field that caused inflation up until that point--so that energy was already there and there had already been plenty of time for its gravitational effect to be "noticed".
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How is it the right order of magnitude? Did you compute that based on the size of the observable Universe? But that's arbitrary, the Universe is way bigger than that.
No. The input into the equation is the density of matter in space, nothing having to do with the size of the observable universe. On large scales in the visible universe, matter is fairly evenly distributed at a density of about 1 atom of hydrogen per cubic meter. For any constant nonzero density form of matter, if you pack enough of it together in a sphere in a flat spacetime, its Schwarzchild radius will eventually…
You can't do this in flat spacetime, because the matter curves spacetime, and the denser you pack it, the more it curves spacetime.
Dark matter is a supersolid that fills 'empty' space, strongly interacts with ordinary matter and is displaced by ordinary matter. What is referred to geometrically as curved spacetime physically exists in nature as the state of displacement of the supersolid dark matter. The state of displacement of the supersolid dark matter is gravity. The supersolid dark matter displaced by a galaxy pushes back, causing the stars…
what are you talking about dude, could you point to something on the arxiv?
The Earth displaces the 'stuff'. The displaced 'stuff' pushes back. The displaced 'stuff' pushing back is gravity.
Curved spacetime = Geometrical representation of gravity.
Displaced supersolid dark matter = Physical representation of gravity.
Isn’t “dark matter” just a way to account for an unexplained behavior? It bothers me that its existence is treated as a given, when it could be a case of mistaken assumptions. If calculations say the universe is acting as if it contained much more mass than we observe, we should also consider the possibility that our method of calculation may be flawed. I’m not claiming dark matter doesn’t exist, only that I fear the…
Yes, Dark Matter is a statement about the premise that something appears to be operating gravitationally while have no (or perhaps so little that we don't recognize it) interaction with other matter; however, it is not without reason. The primary focus on matter as the candidate is that if you don't believe that some form of matter is responsible, you begin having to explain how a lot of our Laws are incorrect. Dark…
I'm completely ignorant of the subject so I don't know how crazy that might sound.
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Even a car constantly accelerating for a long time was still at t0.
A big bang event could explain the reason why the universe expanded in the first place, but it does not explain the accelerating expansion of the universe currently, forgive me for my ignorance if any, but in physics I was taught that any object which moves or is in constant motion was acted upon by a force, and so if the big bang created an expansion it will be a constant expansion and not an accelerating expansion…
The expansion is an expected behaviour of space time, and is predicted by general relativity given a certain parametrization of the density of matter an energy of the universe. To explain the acceleration, though, a large energy parameter is required, which has not been yet identified with any known process, although many theories exhist; as placeholder the parameter is known as dark energy. It is of course possible, but generally considered unlikely, that general relativity is incomplete and another theory could explain the acceleration without dark energy.