[Closed] Beam me up Scotty ?

Quantum entanglement is one of those areas my BA(Hons) background is struggling with a little...

What is the proposed mechanism for entangled protons to simultaneously change state over great distances?

Obviously, just interested in how this technology could help me get faster downloading times. 😀

watch out for flies.

"Spooky action at a distance" - Einstein.

What chance to the rest of us have?

I think they are teleporting information, not the photon itself.

It won't get you faster downloading times unless you are on Mars.

Not sure it's teleportation, just demonstrating the potential use of quantum entanglement to transmit information? Changing states of particles (effectively 0s and 1s) instantaneously over any distance?

As above, it's information but that's not as good a story as teleportation

But, the whole entanglement thing is amazing and makes no sense at the same time

Agreed. When I first heard Brian Cox describe it a few years ago it totally blew my mind. Proper awe inspiring idea while simultaneously being utterly perplexing.

As above, it's information but that's not as good a story as teleportation

It's teleportation of information. You are probably blasé about that because you are used to beaming information around the world anyway. But that is being transmitted and has to travel, at a finite speed. Information teleported simply appears at the other end instantly. No-one knows if there is a distance limit on this effect. You could be pressing a button on earth and a light could be flashing on and off on the other side of the galaxy in real time.

It's amazing stuff. I like the notion that the entanglement is because they are joined in a dimension we are not aware of (yet) - like two dots on a sheet of paper that can be next to each other if that paper is folded in half.

Also..

[url= https://imgs.xkcd.com/comics/quantum.pn g" target="_blank">https://imgs.xkcd.com/comics/quantum.pn g"/> [/img][/url]

😆

everything is just information

I read the article twice, still blooming confused.

Is science difficult to keep the plebs away from it ?

Why are you confused?

Two photons can be linked together so that if you change the state of one, the other changes instantly. You can move them apart and it still does it.

I was confused by the use of the word "teleport" as that suggests the same particle being relocated in space.

OTOH I also get why "transmit" wasn't used instead as that has other connotations, though it's probably closer to what folk understand.

Why are you confused?

Two photons can be linked together so that if you change the state of one, the other changes instantly. You can move them apart and it still does it.

Well yes, that has been repeatedly observed, the confusing thing is trying to work out how it is achieved - we're talking about some kind of transfer of state at thousands of times the speed of light.

Has anyone come up with a plausible mechanism yet?

the confusing thing is trying to work out how it is achieved

In what terms?

This is just how it works. The states change because they are etangled, in the same way that your gears change when you pull on the cable.

You can't understand it in terms of what you know about the world, because none of that applies. So it's pointless to even try.

martinhutch - Member
Has anyone come up with a plausible mechanism yet?

You can't understand it in terms of what you know about the world, because none of that applies. So it's pointless to even try.

And there folks, is the basis of religion.

You could be pressing a button on earth and a light could be flashing on and off on the other side of the galaxy in real time.

Sadly not... rules of 'new information' transfer (e.g. the status of a button being pressed right now) still apply (i.e. nothing faster than light)

What you can do is really quite limited - effectively you can know whether the button was pressed [i]at the time the photons were originally entangled[/i]. This would be useful for encrypting the message 100% securely, but the message still has to be sent at normal light-speed-or-slower.

At least that is my layman's understanding and it seems to correlate with online references to uses of quantum entanglement e.g. [url= https://en.wikipedia.org/wiki/Faster-than-light#Quantum_mechanics ]Wikipedia[/url]

You can't understand it in terms of what you know about the world, because none of that applies. So it's pointless to even try.

And there folks, is the basis of religion.

It's partly correct though - you can't use 'normal' scale analogies e.g. imagining photons as tiny marbles, because they just don't follow the same basic rules like e.g. being in one particular place at any one particular time.

What you [i]can[/i] do, unlike religion, is work out what the new rules are by doing experiments, and test them, and use them to make predictions, and those rules work - even though they make no sense when you (and me, and all humans) have grown up learning how the world works through 'normal' scale behaviour.

Yes. It's called quantum entanglement.

That's not a proposed mechanism. It simply describes what's being observed in terms of the relationship between the paired protons.

I appreciate that humans are programmed to view science as actions which can be explained in a linear cause - effect way and this looks increasingly lacking...

From that Wiki link:

Wavefunction collapse can be viewed as an epiphenomenon of quantum decoherence, which in turn is nothing more than an effect of the underlying local time evolution of the wavefunction of a system and all of its environment. Since the underlying behaviour does not violate local causality or allow FTL it follows that neither does the additional effect of wavefunction collapse, whether real or apparent.

Thanks, that clears that right up...

[img] [/img]

I was confused by the use of the word "teleport" as that suggests the same particle being relocated in space.

If you want to get your brain in even more of a mess have a think about how consciousness, physical matter and information are intertwined.

ie: are 'you' the physical atoms currently bound together to form your body, are are 'you' actually something more ephemeral that can be described as information?

Your consciousness, your memories, and how your brain functions are a result of the physical organisation of the matter that makes up your brain, and the electrical impulses that whizz around it, all of which can be described using information, whether it's physical state of the matter, or eletrcial potentials, but essentially 'you' ARE information.

If your brain and body could be replicated (sub)atomically identical* but 'over there somewhere' so that it functioned in the exact same way and had the exact same information state would that be a new 'you'? a duplicate 'you'?

Obviously from that moment on the duplicate will accumulate a different experience in space and time and differ from the original, but what if the original was destroyed at the exact same time the new one was created? is it still a duplicate? or has the original in a sense been 'teleported' ? the matter may not have physically moved but if all information that describes the configuration of that matter has been then the 'whole' can thought to have been moved, even if the individual physical components haven't.

If you can view physical matter as represented by information state then you get into the blurred area of whether anything is physical at all, it is afterall just particles in a given state, if you can manipulate the state you cna manipulate the particle, and manipulate the matter.

Obviously we don;t yet have capability anywhere near that level but often the problem with concepts as obtuse as quantum mechanics is that you can't relate it to 'normal' things and it's hard to imagine uses for things you don;t yet fully understand or have control over. It's certainly not something to dismiss as simply a scientific curiosity with no practical uses, we don't know what the uses might be yet.

FWIW, I have a masters degree in Physics and wouldn't even dream of saying I understand it all properly, but it's interesting and fascinating and I love the opportunity to just 'think' about this kind of stuff from time to time...

* this is essentially just 'information' as in [i]state [/i]of particles

Wavefunction collapse can be viewed as an epiphenomenon of quantum decoherence, which in turn is nothing more than an effect of the underlying local time evolution of the wavefunction of a system and all of its environment. Since the underlying behaviour does not violate local causality or allow FTL it follows that neither does the additional effect of wavefunction collapse, whether real or apparent.

Thanks, that clears that right up...

😀

I think, roughly translated, that means:

This particular way that photons act weirdly is just a side effect of the general way that photons act weirdly, which, while weird, is sufficiently well understood that we know that it still follows the rule that nothing of any use can travel faster than light.

this is essentially just 'information' as in state of particles

As I understand it, that's the bit where you need the Heisenberg Compensators.

All I'm hearing, and reading, is some crackle of white noise emanating from inside my right ear from a rock falling on a planet 1bn miles away and a photon being squished because another rock in a lab in Switzerland was dropped on the floor whilst the assistant was carrying some colouring in pens.

Gah, it's complex.

Whilst I "get" forget what you've learned (not a difficult task in my instance) but the "teleportation" element guided me down a route that said..
We squashed a photon here on earth, simultaneously in a satellite "out there" recorded a photon being squashed at the same time.
So, was it the same photon or another one?

I'm happy to be taken the piss out of BTW, because I have no comprehension of what this experiment is trying to prove/disprove/nullify.

Think of it like twin brothers, separated since birth, living in London and New York. The one in London gets shot in the head. The one in New York dies at the exact same moment.

You know that it happened, that there is some kind of relationship between the two brothers which has made it happen, but now you have to try to work out how.

dangeourbrain - Member

And there folks, is the basis of religion.

well, not really.

entanglement happens, it can be reliably reproduced and observed.

a bit like Eulers buckling calculations, they work, they're useful, but really, we've all got better things to worry about than trying to understand them.