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Gödel's solution to Einstein's field equations (2021)

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Re: Gödel's solution to Einstein's field equations (2021)

#21

Post by chatmasta »

superposeur wrote: post #18
pocketleaf wrote: post #11

Earlier quoted context omitted.

In reality it’s debatable, but within the logic of the fiction universe it holds, yeah? To be able to move those sorts of distances and arrive at a time comparable to the origins absolute time would require the “time travel” aspect of ftl, right?

Most sci fi just pretends relativity doesn’t exist. Yes, the point is that any way to send a signal between space like separated events A and B (in sr or gr) would also allow a return signal to be sent back from B to event C in the past of A. So any means of ftl signaling (wormhole, warp drive or whatever) is tantamount to building a time m achine. No amount of techno optimism or can-do cleverness will ever be suffic…

I enjoyed this lecture [0] from Scott Aaronson about closed timelike curves and the impact they would have on computational complexity theory. Basically, they would give you the ability to spend an eternity computing some subcalculation, and then return to where you started with the result in hand.

[0] https://youtube.com/watch?v=Ha4eG8gLSK4

Re: Gödel's solution to Einstein's field equations (2021)

#22

Post by BoiledCabbage »

moefh wrote: post #17
explaininjs wrote: post #13

Earlier quoted context omitted.

Nope, entangled pairs are basically the following in JS: class RawQuantum { value = () => this._hidden ??= Math.random() } class EntangledQuantum extends RawQuantum { valueA = () => this.value() valueB = () => 1 - this.value() } const {valueA, valueB} = new EntangledQuantum() You can give valueA to one procedure and valueB to another and know that whenever the _hidden field is observed, the two will have complementar…

That only works if you replace " basically " with " not really ". With this code you can't violate Bell's inequalities[1], which is a really important feature of Quantum Mechanics. [1] https://en.wikipedia.org/wiki/Bell%27s_theorem

For someone who is trying to learn the basics of quantum entanglement, the distinction between local and non-local hidden variables isn't take that essential.

Or make those "hiddens" in the code above globals. Problem solved.

Re: Gödel's solution to Einstein's field equations (2021)

#23

Post by yarg »

renox wrote: post #19
daxfohl wrote: post #5

So to solve physics, you don't just have to be smarter and more creative than Einstein, but than Einstein and Godel combined.

But you know that the Bells equations for the 'spooky action at distance' are violated by QM, which they didn't. Among many other new experiments results..

Spooky action at a distance doesn't need to be a thing.

Retroactive causality implements the same functionality without requiring information to propagate faster than c.

Re: Gödel's solution to Einstein's field equations (2021)

#24

Post by phkahler »

BoiledCabbage wrote: post #22
moefh wrote: post #17

Earlier quoted context omitted.

That only works if you replace " basically " with " not really ". With this code you can't violate Bell's inequalities[1], which is a really important feature of Quantum Mechanics. [1] https://en.wikipedia.org/wiki/Bell%27s_theorem

For someone who is trying to learn the basics of quantum entanglement, the distinction between local and non-local hidden variables isn't take that essential. Or make those "hiddens" in the code above globals. Problem solved.

Non-locality seems to be the least favorable way to resolve the Bell inequalities as far as most physicists are concerned. I'm not sure why though. I think they like exotic and unintuitive sounding stuff.

Re: Gödel's solution to Einstein's field equations (2021)

#25

Post by moefh »

BoiledCabbage wrote: post #22
moefh wrote: post #17

Earlier quoted context omitted.

That only works if you replace " basically " with " not really ". With this code you can't violate Bell's inequalities[1], which is a really important feature of Quantum Mechanics. [1] https://en.wikipedia.org/wiki/Bell%27s_theorem

For someone who is trying to learn the basics of quantum entanglement, the distinction between local and non-local hidden variables isn't take that essential. Or make those "hiddens" in the code above globals. Problem solved.

The problem is not the distinction between local and non-local hidden variables, but the that the "value" in that code doesn't depend on the measurement being performed.

You can't understand anything about quantum mechanics without knowing that in order to measure a qubit (or anything, really) you need an observable, which is completely missing from that JS code (for a qubit, the observable for a simple projective measurement could be represented by a direction in space).

Re: Gödel's solution to Einstein's field equations (2021)

#26

Post by jiggawatts »

superposeur wrote: post #4
thedudeabides5 wrote: post #3

Does this mean that traveling faster-than-light can be considered a form of time travel?

Yes, which is why sci fi scenarios in which ships whiz between star systems will never, ever, ever happen.

I’ve never quite understood why this is so certain.

If I instantly teleported to Alpha Centauri, that wouldn’t put me in the future.

Sure, if I turned a telescope back towards our system and watched Earth, I would see myself wandering around as I was four years ago and then… after four years… I could watch myself step into a teleporter.

This is entirely consistent and in no shape, way, or form would this let me get super rich on the stock market.

You could only ever know information from your present or your past.

Imagine a hypothetical universe with a maximum speed ‘s’. The creatures in this universe could develop relativity and everything, the same as us. But what if ‘s’ is the maximum speed of sound in the gas that fills this toy universe? What if the creatures are all blind and use only sonar to get to know their world? Would travelling faster than ‘s’ be violating causality somehow? Or would it simply be the same as a supersonic plane, leaving a sonic boom behind it?

Having said all that, I very strongly suspect that FTL will never be possible. However, I don’t agree that it would result in time travel if it were possible.

Re: Gödel's solution to Einstein's field equations (2021)

#27

Post by shsbdncudx »

jiggawatts wrote: post #26
superposeur wrote: post #4

Earlier quoted context omitted.

Yes, which is why sci fi scenarios in which ships whiz between star systems will never, ever, ever happen.

I’ve never quite understood why this is so certain. If I instantly teleported to Alpha Centauri, that wouldn’t put me in the future. Sure, if I turned a telescope back towards our system and watched Earth, I would see myself wandering around as I was four years ago and then… after four years… I could watch myself step into a teleporter. This is entirely consistent and in no shape, way, or form would this let me get s…

You could do something on Alpha Centauri, instantly teleport back, and then make a bet on what’s going to be observed in 4 years time.

Re: Gödel's solution to Einstein's field equations (2021)

#29

Post by renox »

yarg wrote: post #23
renox wrote: post #19

Earlier quoted context omitted.

But you know that the Bells equations for the 'spooky action at distance' are violated by QM, which they didn't. Among many other new experiments results..

Spooky action at a distance doesn't need to be a thing. Retroactive causality implements the same functionality without requiring information to propagate faster than c.

Given that you can't use quantum entanglement to send information, I fail to see where information is propagated faster than C.

Re: Gödel's solution to Einstein's field equations (2021)

#30

Post by mr_mitm »

jiggawatts wrote: post #26
superposeur wrote: post #4

Earlier quoted context omitted.

Yes, which is why sci fi scenarios in which ships whiz between star systems will never, ever, ever happen.

I’ve never quite understood why this is so certain. If I instantly teleported to Alpha Centauri, that wouldn’t put me in the future. Sure, if I turned a telescope back towards our system and watched Earth, I would see myself wandering around as I was four years ago and then… after four years… I could watch myself step into a teleporter. This is entirely consistent and in no shape, way, or form would this let me get s…

If you "instantly" teleported to alpha centauri, then there would be a frame of reference in which you arrive before you left. To another observer, you would travel back in time. It's not something you can disagree on. Instead, convince yourself by studying the spacetime diagram: http://www.physicsmatt.com/blog/2016/8/25/why-ftl-implies-ti...

Note that "instantly" is ill-defined in SR. Simultaneity of events is observer-dependent.

Edit: this is also known as the tachyonic antitelephone. It's described here: https://en.m.wikipedia.org/wiki/Tachyonic_antitelephone

Instead of warning about shrimp you could easily tell your past self to buy a certain stock.

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