PRIDE CHEKERAwhich when the direction of time is reversed the equations
remains invariant. This is the power of the metric tensor in EFE,
and was the basis of modeling an expanding universe, into a
contracting universe, back in time to the instant of the Big Bang
as discovered by Georges Lemaitre.
Considering T-duality, if we have a model of an accelerating
universe, of radius R, in its expansion, there must also exist a
universe decelerating, of radius 1/R, in its expansion. The Big
Bang according to the string theory was a collision of two brane
worlds, of which the momentum from their collision set a force
which caused the observed expansion.
Multiverse, Wormholes and Parallel universes
M-Theory, of a 11D hyperspace predicts the existence of a
multiverse, billions of 3-sphere bubble universes. All these
universes have different physics. Our universe is just one of
these many universes, and we are trapped on the surface of this
bubble (the present we can't escape), its inside is the past and
outside is the future.
We don't know if there are other multiverses. These universes
are joined by wormholes (Einstein-Rosen bridges) shortest
distances in space-time used when traversing long distances.
Remember l had talked of these wormholes, as l said can be