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View Full Version : Would Black Holes form in a big bang cyclic universe?



WaxRubiks
2014-Aug-04, 02:46 PM
I read some stuff about the book Cycles of Time, by Roger Penrose.......and it said something like, eventually all matter turns to radiation, and at that point you get another big bang, and all the angles and structure of the old universe's radiation are preserved.

If that was true, would that mean that there would be no concentrations of matter, enough to form primordial black holes? If all the radiation was spread out, I mean.

I suppose that it might not mean that...but maybe it could..


eta: 'form', and 'cyclic' in the title..:rolleyes:

Jeff Root
2014-Aug-04, 03:31 PM
I haven't read it and I have no idea why he'd say anything
about it being cyclic, with another Big Bang. I see nothing
which suggests such a thing might happen.

I presume that "eventually" is after an absurdly long time when
all black holes have evaporated and all baryons have decayed.

But so far as I know, not one baryon has been seen to decay.

Ummm ... Which reminds me ... If baryons decay, what happens
to the electrons?

-- Jeff, in Minneapolis

Shaula
2014-Aug-04, 05:04 PM
But so far as I know, not one baryon has been seen to decay.
This is about the opposite of the case. All bar one baryon have been seen to decay.

JohnD
2014-Aug-04, 05:11 PM
This week's New Scientist has an article, Einstein's Perfect Theory, which shows how General Relativity is making a comeback from being obscured by Quantum, and that new work, such as the recent evidence (disputed) of gravity waves, will open it up to new ways of thinking. That, as the article says, GR wil be 're-booted'!
Read it if you can at: http://www.newscientist.com/article/mg22329800.500-einsteins-perfect-theory-general-relativity-rebooted.html

To quote one sentence, relevant to the above, "The multiverse is ... a steady state of creation and destruction"

John

Jeff Root
2014-Aug-04, 10:05 PM
Make that "proton" then. Not one proton has been observed
to decay. I walked all around the detector myself, 2340 feet
underground, and didn't notice a single proton that wasn't in
fine form.

:p

-- Jeff, in Minneapolis

WaxRubiks
2014-Aug-04, 10:32 PM
protons get tired of being positive all the time.

John Mendenhall
2014-Aug-04, 10:50 PM
Ummm ... Which reminds me ... If baryons decay, what happens
to the electrons?

-- Jeff, in Minneapolis

They barium.

Sorry Jeff, couldn't resist it.

LookingSkyward
2014-Aug-05, 01:08 AM
:rofl:

Reality Check
2014-Aug-05, 02:49 AM
This is Conformal cyclic cosmology (http://en.wikipedia.org/wiki/Conformal_cyclic_cosmology)

The conformal cyclic cosmology (CCC) is a cosmological model in the framework of general relativity, advanced by the theoretical physicists Roger Penrose and Vahe Gurzadyan.[1][2][3] In CCC, the universe iterates through infinite cycles, with the future timelike infinity of each previous iteration being identified with the Big Bang singularity of the next.[4] Penrose popularized this theory in his 2010 book Cycles of Time: An Extraordinary New View of the Universe.