181–190 of 248 posts
I've always liked the theory that every black hole has a white hole on the other "side" that spews out a universe from the information it collects. And the original black/white hole? Well, something something quantum fluctuation something out of nothing.
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.
That seems to be a personal problem. There's nothing inconsistent about either space or time being infinite.
Earlier quoted context omitted.
Yea, that is my understanding. He does call it a crazy theory, but its a whole different kind of crazy that most people think of. I've listened to him talk about it and yea, when you actually listen to him you get the vibe of, "its an interesting idea that the math can't really prove or disprove, it may not be right, but it is an interesting thought experiment." I would say it is a step below Fred Hoyle. For those wh…
Should we entertain unfalsifiable theories?
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.
IANAP - why are these ideas so controversial? The article seems to suggest he has some (potentially) supporting evidence, and I don't have an intuition for how damning the counter-argument is ("This would necessitate making all particles lose mass as the universe gets old." Again, IANAP and physics can get weird).
In addition to the empirical lack of convincing evidence, there is also a theoretical problem. In order for CCC to work, you need to assume that all massive particles decay. The is not inconceivable, but involves things like proton decay, which is speculative at best, and electron decay, for which (as far as I am aware) we do not even have a serious speculative mechanism.
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.
The universe being finite in any way is even harder to grasp for me. How can existence itself have a beginning?
Then how did the first one came about? What was there before it, pls don’t tell me nothing because it was nothing for a long time and then something must have triggered the first one. Or was there no first one because of infinity?
> 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…
My understanding was that there was no such thing as inertial frame observers in GR, and that an observer in GR is actually something traveling on a world line in time with a future light cone and a post light cone. The observer portion in GR is literally the ability to observe with light, not a coordinate system as defined from within an inertial frame as in special relativity.
Thats because in GR, because of the curvature of space, you could not extend a coordinate system across all of existence because you knew that in some areas curvature would cause that to be not accurate. You can sort of declare space effectively flat within a local region but not across the entire universe.
It also wasn't clear what someone moving at an co-frame to the average of all the stuff in the universe has to do with faster than light travel - in a spacetime diagram a co-frame would be vertical with a horizontal constant offset, but faster than light travel would have to be in v > c zone not vertical. Maybe I'm too much of a layman to understand the logic she was using but none of it was very clear to me.
Earlier quoted context omitted.
Should we entertain unfalsifiable theories?
"The Earth is round" was once an unsatisfiable theory for quite a while.