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The Paradoxes That Threaten To Tear Modern Cosmology Apart
KentuckyFC writes Revolutions in science often come from the study of seemingly unresolvable paradoxes. So an interesting exercise is to list the paradoxes associated with current ideas in science. One cosmologist has done just that by exploring the paradoxes associated with well-established ideas and observations about the structure and origin of the universe. Perhaps the most dramatic of these paradoxes comes from the idea that the universe must be expanding. What's curious about this expansion is that space, and the vacuum associated with it, must somehow be created in this process. And yet nobody knows how this can occur. What's more, there is an energy associated with any given volume of the universe. If that volume increases, the inescapable conclusion is that the energy must increase as well. So much for conservation of energy. And even the amount of energy associated with the vacuum is a puzzle with different calculations contradicting each other by 120 orders of magnitude. Clearly, anybody who can resolve these problems has a bright future in science but may also end up tearing modern cosmology apart.
The vacuum seems to have energy, so if space itself expands, the vacuum left has to either not have any energy whatsoever or drain the energy from nearby space. And since the energy of the vacuum seems to be constant, the conclusion is that the expansion is creating vacuum with its own energy
Paradox - "a statement or proposition that, despite sound (or apparently sound) reasoning from acceptable premises, leads to a conclusion that seems senseless, logically unacceptable, or self-contradictory."
The paradox is that energy is supposed to be conserved, but space has energy and is increasing. So, we have a logically unacceptable a conclusion.
Just because it is a current paradox doesn't mean it can never be resolved. We find an energy source, or figure out the laws of physics which in this case allow for the creation of energy and is stops being a paradox.
Quantum physics calculations say the vacuum energy is one value while measurements of the curvature of the universe say it is a different value. That is a paradox especially when both Quantum physics and the physics involved in measuring the curvature of the universe seem to both be right in other respects such that making changes to resolve this paradox causes them to stop describing other things accurately. So, we have logically unacceptable conclusion.
The red shift thing doesn't look like a paradox, but a really cool test of our understanding of cosmological red shift.
And, the homogeneity problem could be a paradox linearity of expansion says the universe is homogenous, observations say it is not. But, they don't mention whether observations have done a reasonable job of determining the dark matter distribution of the universe.
There are paradoxes in the article, but it does drift into one topic that is not a paradox and another that is borderline.
Even professional physicists like some good numerology sometimes.
Also, just so we're clear, you took a number e-26, multiplied it by a number e+23, and you ended up with a number e+0?
Don't blame me, I voted for Baltar.
in fact, general relativity doesn't conserve energy anyways,
GR does conserve energy, but in a very messy way with a lot of subtleties that means it gets skipped over in the grad level intro courses. Especially when dealing with an expanding metric, it is possible to formulate a contrived analogy to potential energy.
There was a beginning to the universe (which alone breaks the symmetry: you can't shift backwards in time more than ~13 billion years), and the universe as it is now looks nothing like it did 10 billion years ago.
The beginning of the universe does not need to conserve energy, but things as far as we can tell are conserved after that. The fact that things look different doesn't contradict the type of symmetry needed by Noether's theorem, just as Noether's theorem applies just fine in classical mechanics despite the second law of thermodynamics.