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Two weeks before death, Hawking submitted a paper on parallel universes

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Re: Two weeks before death, Hawking submitted a paper on parallel universes

#41

Post by akvadrako »

nahumfarchi wrote: post #20
hnarn wrote: post #8

Earlier quoted context omitted.

>If there are truly separate "universes", then by definition wouldn't it be the case that there would be no way to test (or falsify) whether they exist or not This literally contradicts what the first paragraph of the article. It says that this paper "lays the theoretical groundwork for discovering a parallel universe". If you've discovered it, you've tested and proved that it exists. Furthermore, the article states…

Isn't it the other way around? You start out with assumptions and a model (which usually involves some math), and then you show that you've made the correct assumptions by empirically testing it. You can't prove something in the mathematical sense about physical reality.

Of course you can; if you prove, given the indirect evidence, it's the only possibility.

Re: Two weeks before death, Hawking submitted a paper on parallel universes

#42

Post by akvadrako »

andygates wrote: post #32
einrealist wrote: post #26

Earlier quoted context omitted.

How is the Hawking ID generated? Which universe is used for synchronization? Do we need a new UUID level? Will the NISTs of all universes ever come to an agreement? So many questions...

Multiversally-Unique ID's are going to be so long...

I was going to disagree because our universe seems to be very compressible and a lot of the properties are just natural. I bet it could be defined in 0 - 100 bits at the "earliest" point.

But over time, QM seems to make lots of arbitrary decisions and those also seem to create different universes if they end up contributing to macro behavior.

Re: Two weeks before death, Hawking submitted a paper on parallel universes

#43

Post by jfaucett »

zaarn wrote: post #36
andygates wrote: post #32

Earlier quoted context omitted.

Multiversally-Unique ID's are going to be so long...

Depends on how many of them there are. If there is infinite, there is no MUID, if it's finite and below 2^64 then a traditional UUID should be enough to assign a UUID per universe and then assing a UUID for objects within.

> If there is infinite, there is no MUID

Formally, you could still have MUIDs even if there are infinite universes so long as they are countably infinite. Practically, the system would work as well so long as you could allocate new qbits to boost your information exponent.

Re: Two weeks before death, Hawking submitted a paper on parallel universes

#44

Post by davrosthedalek »

akvadrako wrote: post #41
nahumfarchi wrote: post #20

Earlier quoted context omitted.

Isn't it the other way around? You start out with assumptions and a model (which usually involves some math), and then you show that you've made the correct assumptions by empirically testing it. You can't prove something in the mathematical sense about physical reality.

Of course you can; if you prove, given the indirect evidence, it's the only possibility.

You have to prove that math actually maps to reality. I don't think you can do that. With the possibility that it's all a simulation, our universe doesn't even have to be consistent.

Re: Two weeks before death, Hawking submitted a paper on parallel universes

#45

Post by zaarn »

jfaucett wrote: post #43
zaarn wrote: post #36

Earlier quoted context omitted.

Depends on how many of them there are. If there is infinite, there is no MUID, if it's finite and below 2^64 then a traditional UUID should be enough to assign a UUID per universe and then assing a UUID for objects within.

> If there is infinite, there is no MUID Formally, you could still have MUIDs even if there are infinite universes so long as they are countably infinite. Practically, the system would work as well so long as you could allocate new qbits to boost your information exponent.

Well, no, as long as you want a finitely long MUID since a finite number of digits can only express a countable but not infinite number of elements.

Re: Two weeks before death, Hawking submitted a paper on parallel universes

#46

Post by akvadrako »

davrosthedalek wrote: post #44
akvadrako wrote: post #41

Earlier quoted context omitted.

Of course you can; if you prove, given the indirect evidence, it's the only possibility.

You have to prove that math actually maps to reality. I don't think you can do that. With the possibility that it's all a simulation, our universe doesn't even have to be consistent.

Why not just simplify your whole position to "you can never prove anything"?

Re: Two weeks before death, Hawking submitted a paper on parallel universes

#47

Post by tutts »

erric wrote: post #18
russdpale wrote: post #3

Truly amazing. Thank you Professor Hawking! RIP.

This statement is in the same domain as “thoughts and prayers”, which is the same as saying, ”I’m wishing at you really hard”. Rest implies an awaking or movement at some point in the future, but for Hawking, he didn’t believe in that. Maybe it’s just something to say, like acknowledging someone sneezing?

Or maybe it's a metaphorical expression of sadness over the recent death of a respected idol?

Re: Two weeks before death, Hawking submitted a paper on parallel universes

#48

Post by jfaucett »

zaarn wrote: post #45
jfaucett wrote: post #43

Earlier quoted context omitted.

> If there is infinite, there is no MUID Formally, you could still have MUIDs even if there are infinite universes so long as they are countably infinite. Practically, the system would work as well so long as you could allocate new qbits to boost your information exponent.

Well, no, as long as you want a finitely long MUID since a finite number of digits can only express a countable but not infinite number of elements.

We don't want a finitely long MUID, otherwise we couldn't represent infinite universes. A quantum bit represents infinite states. The "fiction" part is that we (currently) need to collapse quantum bits.

Re: Two weeks before death, Hawking submitted a paper on parallel universes

#49

Post by pegasus »

codeulike wrote: post #40

Quite a lot of people worrying about the definition of the word 'universe' in this thread.

And with good reason. "Discovering a parallel universe" is nonsensical in the common acceptance of those words. Parallel lines never meet and the universe by definition contains all there is. So people are grasping for alternative definitions of the words that might make the statement satisifiable.

Re: Two weeks before death, Hawking submitted a paper on parallel universes

#50

Post by maxerickson »

sgt101 wrote: post #38
nanofortnight wrote: post #31

Earlier quoted context omitted.

That's exactly it. Atom comes from atomos, meaning indivisible; if you take the literal meaning, it has no constituent parts.

But that's pretty unreasonable as a line of argument; the derivation of a word from a long dead language has no bearing on the semantic in modern discourse. Atoms have been known to be divisible for over 100 years, the consequences of this knowledge are everywhere in our society!

It was in modern usage prior to being adopted in chemistry, it isn't just the derivation.

But that's just the point, instead of using a new word for atoms when sub particles were discovered, the existing meaning was set aside.

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