Before the Big Bang

[Stranger]

I mentioned Penrose's conformal cyclic cosmology in the The infinitely old universe thread but somebody on another forum pointed out this video, which it explains it really quite well: Before the Big Bang 7: An Eternal Cyclic Universe, CCC revisited & Twistor Theory. It's almost an hour but it's well worth watching for those interested in this sort of thing.

It also turns out to be part of a whole series of films about different ideas in cosmology. The issues of entropy, the arrow of time, 'fine tuning', falsifiability (is it real science?), and Boltzmann brains are addressed in many of the different cases.

For pop-science programmes they seem to be really well done (they avoid the usual howlers at least) and most of the material is from people directly working on the ideas. So, here are all the links if anybody's interested:

Before the Big Bang 1 - Loop Quantum Cosmology Explained
Before the big bang 2 - Conformal Cyclic Cosmology explained (part 7 is an update of this)
Before the Big Bang 3: String Theory Cosmology (unfortunately there's no sound for about the first minute)
Before the Big Bang 4 : Eternal Inflation & The Multiverse
Before the Big Bang 5: The No Boundary Proposal
Before the Big Bang 6: Can the Universe Create Itself?
Before the Big Bang 7: An Eternal Cyclic Universe, CCC revisited & Twistor Theory
Before the Big Bang 8: Varying Speed Of Light Cosmology (VSL)
Before the Big Bang 9: A Multiverse from "Nothing"
Before the Big Bang 1O : Black Hole Genesis

They reveal how many different ideas there are, how much we don't know, and the extreme difficulty of testing ideas of this nature, but there are some quite interesting similarities between some essentially different approaches.

[Udayana]

Thanks, nice to have a list of references.

[torridon]

Good stuff, thanks; lots of material there 

[SusanDoris]

Although I do have the time to listen to those videos, I don't think I will, but it all sounds very interesting indeed.
Unfortunately, I think it is morelikely that this galaxy will have caused the extinction of all species before any one of our species has managed to work out what came before the very beginning of all those universes!

[Alan Burns]

Although I do have the time to listen to those videos, I don't think I will, but it all sounds very interesting indeed.
Unfortunately, I think it is morelikely that this galaxy will have caused the extinction of all species before any one of our species has managed to work out what came before the very beginning of all those universes!

The concept of "before" is not quite right concerning universes in which time began.  The word "outside" might be more appropriate.
There are many different man made theories which try to make sense of our existence and origins, none of which can be tested from what exists on this cooling crust of star debris we call earth.  Our conscious ability to contemplate such matters is a wonder in itself.  Can we honestly say how such an ability came into existence ?

[jeremyp]

The concept of "before" is not quite right concerning universes in which time began.  The word "outside" might be more appropriate.

Given general relativity, "before the Universe began" and "outside the Universe" are very similar - if not the same - concepts. Neither is well defined, at least under some models.

[Sebastian Toe]

Can we honestly say how such an ability came into existence ?

Do you not say, with a degree of conviction, how it came into existence?

[Stranger]

There are many different man made theories which try to make sense of our existence and origins, none of which can be tested from what exists on this cooling crust of star debris we call earth.

Actually many of them do make predictions (generally about patterns in the CMB or gravity waves) that are, at least in principle, testable. And all of them have the distinct advantage over the fairy tales of religion in that they are extrapolated from theories that have been tested.

Our conscious ability to contemplate such matters is a wonder in itself.  Can we honestly say how such an ability came into existence ?

Yes, there is plentiful evidence of how it came into existence.

[Stranger]

Part 11:

Before the Big Bang 11: Did the Universe Create itself ? The PTC model