Simultaneous expansion and contraction in a torus shaped closed timelike curve
According to this cosmological model the multiverse is like a sea with waves going around a torus shaped closed timelike curve. Our universe is just one wave in sea of the multiverse. There is however an almost infinite amount of such waves both before and after us. Waves before us have a higher entropy while waves after us have a lower entropy. Since there are much more paths to higher entropy than to lower entropy, each wave has an almost infinitely higher probability of moving towards higher entropy. The exact configuration of the future for each wave is however somewhat indeterminate as it can move to an almost infinite amount of parallel realities.
A popular interpretation of quantum physics is called the many-worlds interpretation. According to this interpretation, the universe splits into all possible outcomes as we move forward in time. But according to the famous physicist Richard Feynman there should also be multiple histories then. Because if a trajectory can split into the future, trajectories from the past can also converge.
All the particles we know of in the observable universe seem to be traveling at subluminal velocities. These subluminal particles seem to always travel ahead in time. If however particles were to travel at superluminal velocities they might be able to travel back in time. According to Einstein's special theory of relativity an infinite amount of energy is required to accelerate a particle to the speed of light, but according to quantum mechanics particles have a range of superpositions with different velocities. So with enough energy particles with velocities close to the speed of light might be able to transcend the light speed barrier by quantum tunneling to superluminal superpositions.
The escape velocity is greater than the speed of light within the event horizon of a black hole, so there particles might have enough gravitational energy to transcend the light speed barrier with quantum tunneling. At superluminal velocities particles should be able to travel back in time. So the event horizon might act as a spacetime rift between the universe progressing forwards and in reverse, which enables the universe to form a closed timelike curve from the black holes back to the white hole at the beginning of time. There is an infinite amount of gravitational time dilation at the event horizon itself, so the universe isn't located at any specific moment of time there, but rather all moments of time exist simultaneously. From there the universe might appear as a probability distribution of all possible configurations, much like an electron surrounding a hydrogen nucleus appears as a probability distribution to us.
The size of the universe is determined by how rough it is. Concentrations of mass create roughness that stretches the universe so that more space is generated. The universe is smallest at the smooth beginning of time. Then the universe expands as it becomes rougher, until eventually it reaches its peak of size and roughness when almost all matter is captured in black holes. Then it starts to become smoother and smaller as black holes evaporate due to Hawking radiation. Eventually it reaches the smallest size at the smooth end of time, which coincides with the smooth beginning of the next cycle. Some black holes might not evaporate completely before the next cycle starts. These become primordial black holes in the next cycle.
Biological life seems to have risen on earth from simple organic molecules in a process called abiogenesis. Life should therefore also emerge on other planets that have the right environmental conditions for abiogenesis to occur. Another interesting aspect about the biological evolution on earth is that the highest level of complexity has increased over time. This is not because more complex life is more successful, but rather because more complex life can utilize niches unavailable to less complex lifeforms. The top-level complexity probably increases according to a sigmoid function, and life on all planets might be evolving towards the same superorganism found at the end of the sigmoid curve. As our universe evolves from the white hole at the beginning of time to the black holes at the end of time, this superorganism might simply be awakening from a period of sleep.
Consciousness seems emerge from quantum chaos in complex systems, which isn't necessarily reducible to the smaller constituents of the complex system. The wholeness of the universe can therefore be considered to be more than the sum of its parts. All subsystems share the larger system they are a part of and properly functioning subsystems should therefore always work to maintain the health of the larger system. Properly functioning neurons in a nervous system work to maintain the health of the nervous system, while dysfunctional cancer cells only work to multiply themselves. Properly functioning nervous systems should in a similar fashion work to maintain the health of the biosphere, rather than to deteriorate the health of the biosphere with overpopulation and overconsumption.