
Big Bounce Simulations Challenge the Big Bang - theafh
https://www.quantamagazine.org/big-bounce-simulations-challenge-the-big-bang-20200804/
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PaulHoule
People were running simulations like this circa 2005, but it seems the new
thing here is that the collapse causes smoothing and replaces the 'need' for
inflation.

Steven Hawking held back quantum gravity for about 30 years by keeping the
idea of information loss around black holes alive. If you take that seriously,
you give up unitarity, which is the basic requirement for doing quantum
mechanics (the requirement for unitarity played a big role in my PhD thesis --
unitarity means "the probability that some outcome occurs is one".

If you accept that then it is easy to get a "big bounce" or just about
anything except the universe bursting out of a singularity at time 0.

