Stephen talks, Universe listens

Stephen talks, Universe listens

Jan 01, 2019 / By : / Category : 老域名购买

Stephen Hawking is one of science's quintessential iconic figures. When he opens his mouth to speak the rest of us shut up and listen. Thus it was with great interest that I noted he had published a new article. It goes without saying that Hawking talks of nothing less than the origin of the universe, however, unlike other papers on the subject which I have tried to present here, I could actually understand some of this without too much effort. That is the sort of thing I really appreciate. 老域名出售

Theoretical cosmology usually works in the same way that everything else in physics works. Figure out the initial conditions, figure out the fundamental physics. Apply the initial conditions to the fundamental physics and out falls all the answers you could hope for. Unfortunately when this approach is applied to cosmology, one ends up with a finely tuned universe, where the initial conditions must be very precisely defined to get the universe we observe. The cause of this problem, according to Hawking, is that we are essentially in the middle of the experiment and are thus in no position to determine what the result from any initial conditions are. His solution has been to figure out how to solve the governing physics without initial conditions, but instead use what might be considered later conditions to help constrain the system. Combine this with the quantum nature of the universe and what you get is the wave function for the universe, which doesn't require a special state to get the way we observe it to be.

In some respects, this looks a lot like the anthropic principle at work and there is no problem with this, since we are not selecting boundary conditions that lead to what we observe. Better yet, the no boundary conditions approach naturally leads to inflationary periods such as that experienced by the early universe and the one we are currently experiencing. Not only that, this approach should lead to predictions on the structure of the cosmic microwave background, which should distinguish it from other competing approaches.

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