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Proving our universe is one among many would be a fourth Copernican revolution

nautil.us

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Re: Proving our universe is one among many would be a fourth Copernican revolution

#31

Post by nbulka »

lisper wrote: post #16
Retric wrote: post #15

Earlier quoted context omitted.

For now we can just by waiting. With every second we see just a little further. Tomorrow we might look out at the stars and see the tips of giant teeth. But, probably not.

You don't quite understand the concept of a light cone. Yes, we get new data all the time, and the extent of our horizon is growing. But it is always finite . You cannot look backwards past the big bang singularity, and you cannot look forwards beyond "now" for any value of "now".

You may want to temper your claims with "based on the currently accepted Standard Model" or "with high probability." Because paradigm shifts occur.

Re: Proving our universe is one among many would be a fourth Copernican revolution

#32

Post by lisper »

nbulka wrote: post #31
lisper wrote: post #16

Earlier quoted context omitted.

You don't quite understand the concept of a light cone. Yes, we get new data all the time, and the extent of our horizon is growing. But it is always finite . You cannot look backwards past the big bang singularity, and you cannot look forwards beyond "now" for any value of "now".

You may want to temper your claims with "based on the currently accepted Standard Model" or "with high probability." Because paradigm shifts occur.

See my OP: https://news.ycombinator.com/item?id=18094991

"Barring some major unforeseen revolution in our understanding of physics..."

Re: Proving our universe is one among many would be a fourth Copernican revolution

#34

Post by btilly »

lisper wrote: post #21
btilly wrote: post #18

Earlier quoted context omitted.

According to current cosmological thought, the laws of physics at that shell are very close to if not identical to the laws of physics here. And yet, that shell is retreating from us faster than the speed of light. The shell is ever expanding, but we shall never see what that current shell will look like when it is 10 billion years. How can that be, you ask? It is quite simple. The speed of light is a limit on how fa…

> within existing theory, the location of "the farthest we can see" is not particularly meaningful physically Except that you can always put a finite upper bound on that distance. That is what matters with regards to the topic under discussion.

Which means that it is exactly as meaningful as the event horizon of a black hole. The last point where the external observer (ie us) can see what happens. But in a different coordinate system, not particularly special at all.

Re: Proving our universe is one among many would be a fourth Copernican revolution

#35

Post by mortenjorck »

> “The long-term future probably lies with electronic rather than organic ‘life.’”

I guess this is the standard transhumanist position, but it strikes me as both pessimistic and overconfident. Pessimistic because it doesn’t see the life that arose against all odds on this rock as fit for or worthy of continuation on a solar timescale, and overconfident in its implication that we will inevitably create something in our image that will succeed us.

Re: Proving our universe is one among many would be a fourth Copernican revolution

#36

Post by tvmalsv »

jbattle wrote: post #26
excalibur wrote: post #23

> At first sight, the concept of parallel universes might seem too arcane to have any practical impact. But it may (in one of its variants) actually offer the prospect of an entirely new kind of computer: the quantum computer, which can transcend the limits of even the fastest digital processor by, in effect, sharing the computational burden among a near infinity of parallel universes. I'm far from an expert on quant…

Similarly, by the copernican principle, wouldn't our "local" quantum computer also then be burdened by the work being sent from a near infinity of parallel universes?

I would say "yes" to that. But fortunately, with the load being so widely distributed, the load on our "local" quantum computers would effectively be zero (ie. x/inf). Unless, of course, our universe is the oddball and most others are running at full capacity. That's a depressing possibility.

Re: Proving our universe is one among many would be a fourth Copernican revolution

#37

Post by kgwgk »

excalibur wrote: post #23

> At first sight, the concept of parallel universes might seem too arcane to have any practical impact. But it may (in one of its variants) actually offer the prospect of an entirely new kind of computer: the quantum computer, which can transcend the limits of even the fastest digital processor by, in effect, sharing the computational burden among a near infinity of parallel universes. I'm far from an expert on quant…

If they are relevant for a quantum computer, then they are not parallel universes. They are part of "our" universe.

Re: Proving our universe is one among many would be a fourth Copernican revolution

#38

Post by lisper »

btilly wrote: post #34
lisper wrote: post #21

Earlier quoted context omitted.

> within existing theory, the location of "the farthest we can see" is not particularly meaningful physically Except that you can always put a finite upper bound on that distance. That is what matters with regards to the topic under discussion.

Which means that it is exactly as meaningful as the event horizon of a black hole. The last point where the external observer (ie us) can see what happens. But in a different coordinate system, not particularly special at all.

Yes, that's right. Different observers have different light cones. Yours is a little different from mine. But that is missing the point, which is that every observer has a light cone beyond which they cannot see -- not even by collaborating with other observers with different light cones.

Re: Proving our universe is one among many would be a fourth Copernican revolution

#39

Post by dsp1234 »

tvmalsv wrote: post #36
jbattle wrote: post #26

Earlier quoted context omitted.

Similarly, by the copernican principle, wouldn't our "local" quantum computer also then be burdened by the work being sent from a near infinity of parallel universes?

I would say "yes" to that. But fortunately, with the load being so widely distributed, the load on our "local" quantum computers would effectively be zero (ie. x/inf). Unless, of course, our universe is the oddball and most others are running at full capacity. That's a depressing possibility.

The load could be zero, it could be infinite, or anywhere in between. Infinite universes sending infinite work is inf/inf. It's not possible to know if that's going to tend towards something like 0 or something like positive infinity without having some way to measure. But it's an error to just assume it's zero.
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