191–200 of 248 posts
No offence, but Sir Penrose has been claiming a lot of very unlikely things the last couple of years without any evidence. Which is fine, philosophy is important, but let’s not put his statements in the realm of actual science.
A hypothesis is part of science. You have to have an idea to have something to test!
This isn't a new idea. It's been kicking around for some time (at least two decades), rather hard to prove/disprove since there's no currently known mechanism, even theoretical, for observing what might have happened befoee the big bang.
That isn't entirely true. As the article discusses, under the proposed conformal cyclic cosmology, gravitational waves would leave a lasting effect visible between aeons. This effect would be visible in the CMB, and some researchers (including Penrose) claim to have found such a signature in their analysis of the CMB. The validity of their analysis is still in dispute (because detecting such a signal from the noise o…
If all matter is re-crunched into a "singularity," then no space remains? Right? Or time either?
Where do these residual gravity waves exist? If the void of nothingness? That seems wrong.
I guess based on the article that the theory proposes that not everything is re-crunched (dubious?) but that some stuff remains in the universe (dead black holes are somehow not re-crunched?), and therefore space and time do not cease to exist between Bangs and Crunches?
I don't know. I just don't really understand, which is fine as I am a brain scientist not a physicist.
Penrose has a decent amount of lectures available on youtube that give an accessible but comprehensive introduction to his ideas on a cyclic cosmos, of which this is the most recent, afaik. I recommend it for anyone with a couple of hours who wants to understand where he's coming from.
Interesting to note that the idea of the "Big Bounce" has been around a long time. Penrose's claim seems to be that there may be evidence of it in cosmic background radiation hotspots. This was Nietzsche in 1885, musing on how developments in thermodynamics had complicated the mechanistic picture of the universe: > And do you know what "the world" is to me? Shall I show it to you in my mirror? This world: a monster o…
Penrose's theory of conformal cyclic cosmology is distinct from the big bounce theory. In the big bounce theory, the universe reaches a point where expansion slows down and eventually reverses into contraction. Then, eventually the universe reaches a high enough density where something happens and it begins expanding again in a new big bang. In conformal cyclic cosmology, the expansion never reverses. Instead, there…
Earlier quoted context omitted.
"The Earth is round" was once an unsatisfiable theory for quite a while.
This is such a common trope. Erasthenes observed the Earth must be round using shadows over 2 thousand years ago. There was never an intellectual controversy about it before internet dupes fell for an obvious prank.
Earlier quoted context omitted.
Since I haven’t seen anyone else mention this bit of context elsewhere in the thread: Penrose gets a bit of side-eye in the physics community because of his metaphysical beliefs on consciousness. (Specifically, that quantum effects in tubule proteins of the brain produce special nondeterministic effects that constitute our conscious essence, and true consciousness is impossible without this nondeterministic fount of…
Oh this is super cool, thanks for sharing. I have strong (admittedly mostly irrational) inclinations against determinism, seeing something like this is exciting. Definitely going to have to give it a read. Sapolski's take on determinism was really a low blow for me, and I've since seen several other intellectuals I respect very highly espouse similar views, and there was a point where I would have agreed in my adoles…
But a quantum physicist would then ask "to what degree?" because quantum mechanics is very deterministic over large sample sizes (and a few trillion proteins in the brain would be a very large sample).
More importantly though, free will implies the ability to make a choice and that has problems when you invoke quantum indeterminacy to explain it: you don't get "a choice" you get random chance deciding things (and other depressing ideas like "human consciousness can't be backed up, saved or transferred - we really are trapped in these meat prisons and doomed to suffer).
> What proof does the physicist have for this theory he dubbed “conformal cyclic cosmology” (CCC) that goes against the current Big Bang dogma? It doesn't go against the current "dogma", as the Big Bang theory only covers history up until a fraction of a second after the big bang. Anything before that is basically fair game, even though some ideas are further out there than others. Penrose admits it's a "crazy idea o…
I had a hard time understanding the leap she made near the end of her video yesterday about co moving frames. She summarized the time travel theory/paradox as it has been known until now, and then she made some kind of reference to an co moving inertial frame observer ("moving at the same rate as the average of all of the stuff in the universe" paraphrased) she claimed would exist under general relativity. My underst…
She's obviously a very smart and professional physicist, but this video that she published is bordering on crank territory and it makes me wonder if the social media fame has gotten to her somehow. It's truly baffling.
Earlier quoted context omitted.
it's fringe because it's almost certainly nonfalsifiable
I'm pretty sure Penrose won't accept his own theory if it's only nonfalsifiable. At the moment, it's only an idea but if it is unprovable he'll abandon it or be very clear about its non-scientific status. He's not a second Josephson.
The concept of infinity seems impossible to me in physical world. It's a great mathematical concept to model our understanding. Just like imaginary numbers. I cannot imagine anything being infinite in the physical world. I find the simulation hypothesis more probable than Universe being infinite. Space and Time is not infinite. It may be Gazillions of centuries old, but not infinity. It can't be.