Another universe existed before ours

[Gawdzilla Sama]

I know one thing for certain, and that is we'll never know for certain.

[polymath257]

Penrose's CCC model depends upon unexplored physics conjectures.  It's make-believe.

Which is probably why the Nobel Committee didn’t consider it. There’s precedent - Einstein won for optics, not relativity.

Boru

The photoelectric effect is usually not considered to be part of optics. it's more about the response of metals to high energy light.

[Brian37]

I wish I could remember the lady "M-theorist" who was part of a panel that Neil deGrasse Tyson hosted quite a few years ago. The way I remember it, basically she was saying, that no matter what, bubble universe, multi or parallel, "all this" , would basically heat up like boiling water and dissipate.

[BrianSoddingBoru4]

Which is probably why the Nobel Committee didn’t consider it. There’s precedent - Einstein won for optics, not relativity.

Boru

The photoelectric effect is usually not considered to be part of optics. it's more about the response of metals to high energy light.

Oops.

Boru

[FlatAssembler]

As far as I understand it, mainstream physics considers there to have been no time before the Big Bang, so talking about "universe before ours" contradicts that.

[BrianSoddingBoru4]

As far as I understand it, mainstream physics considers there to have been no time before the Big Bang, so talking about "universe before ours" contradicts that.

Not really. If there’s anything to the ‘Big Crunch’ hypothesis (and it’s still in the running), time begins anew with each universe. To say ‘universe before ours’ is a fault of language, not of physics.

Boru

[onlinebiker]

Oh come on - everybody knows it's turtles all the way down......

[polymath257]

As far as I understand it, mainstream physics considers there to have been no time before the Big Bang, so talking about "universe before ours" contradicts that.

It's more accurate to say that the simplest model, based on general relativity, does not allow for the extension of the time coordinate to before the Big Bang.

But, when quantum effects are modeled as well, that singularity at t=0 is 'smoothed out', which allows for time to make sense prior to the BB.

Unfortunately, we do not know which of several quantum gravity models is accurate (if any of the current ones are), so saying anything more is pure speculation.

Penrose was working on aspects of quantum gravity, so it is reasonable to talk about 'before the Big Bang' in that context.

[Gawdzilla Sama]

Oh come on - everybody knows it's turtles all the way down......

I wish.

[no one]

Since our universe got trump, we're probably in the reject pile. Like that one relative so repulsive, they aren't even acknowledged.