From the Newtonian world of eternal time and Universe, we have moved forward and accepted the Einstein-Big Bang universe which is evolving and where space and time are closely related. However, two great theories of twentieth-century
physics – General Theory of Relativity and Quantum mechanics have never converged and predict if one istrue the other can’t be. But experimental evidences till date predict the both to be true to the best precision we can measure. The key to understand our universe according to the new generation of physicist is the entropy and time.
In our universe Time increases, so as randomness and entropy. Universe started from zero entropy, zero space and immense energy according to GTR. If we dig deep into the relation of time and entropy we find when there is a change there is heat and there is space and time. If we imagine the universe where nothing changes – there is no question of entropy – thus no question of time. So time can be unified to the concept of change. We can safely argue that the singularity of space and time is the state of no change and thus no heat and no entropy. Space and time begins with the notion of change and thus the concept of randomness is born.
The laws of nature restrict us to explore both the world of very small, very big as well as the universe prior to big bang. But our ability to imagination and extrapolation is infinite. We thus can imagine that the space time crunch in the black holes of our universe can collapse to the zero entropy state and then evolve to a new universe. Moreover our universe itself may be growing inside another universe. We don’t, and perhaps never will, have any tool to verify these hypothesise.
References:
[1] Smolin, Lee, and John Harnad. “The trouble with physics: the rise of string theory, the fall of a science, and what comes next.” The Mathematical Intelligencer 30.3 (2008): 66-69.
[2] Rovelli, Carlo. Quantum gravity. Cambridge university press, 2007.
[3] Penrose, Roger. Cycles of time: an extraordinary new view of the universe. Random House, 2010.
[4] Carroll, Sean. From eternity to here: the quest for the ultimate theory of time. Penguin, 2010.
