Dark energy is said to be the cause of the accelerated expansion that all galaxies in the universe seem to have wrt each other. This is said to be caused by an accelerated expansion of space itself, but it can also be viewed as an accelerated motion in negatively curved spacetime. In the beginning of the universe, when only virtual particle pairs were present, spacetime was negatively curved. And not a bit. The virtual particles were accelerating away from each other up to the point where they became real. The matter that formed gave spacetime a positive curvature.
So could it be that negative curvature (which makes particles move away from each other) is simply caused by virtual particles, that is could dark energy just be all the virtual particle stuff that's present in spacetime (which would make it an infaton field effectively)?
-
$\begingroup$ There's some good info about the nature of virtual particles here: physics.stackexchange.com/q/230113/123208 $\endgroup$– PM 2RingJun 10, 2021 at 9:01
1 Answer
Yes and no. Yes, according to quantum field theory the vacuum has energy caused by fluctuations of quantum fields (or virtual particles, if you like), and that energy should behave much like the theoretical dark energy. But no, because the originally calculated value for the vacuum energy was 120 orders of magnitude higher than the observed value for dark energy. Later refinement has got that down to 60 orders of magnitude, but it’s still by far the biggest discrepancy between theory and observation. There is something very important that we don’t understand. https://en.wikipedia.org/wiki/Cosmological_constant_problem
-
$\begingroup$ Doesn't that show that the calculations are wrong, or based on a wrong idea of what fluctuations of these fields are? An excitation of these fields is a particle, but what is a fluctuation? Two creation operators followed by two annihilation operators? $\endgroup$ Jun 10, 2021 at 7:10