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0 pointsthedufer11y ago0 comments

I'm skeptical, if only because this should be a big deal and hasn't gotten much press.

> We're able to set the spin (rotational direction) of these particles in a predetermined state, verify this spin and subsequently read out the data.

This is terribly unclear. I don't have access to the article - maybe its better explained there?

The problem with using quantum entanglement for information transfer is that you can't cause a particular spin at either location - they're just both reading random data that correlates. Nothing about this allows any actual transfer of information. Why are they not explaining how they got around this? That's the interesting bit, as far as I can tell.

0 comments

X411y ago

Paper in short: http://download.repubblica.it/pdf/2014/scienze/science-xpres...

Paper in full: http://arxiv.org/abs/1404.4369

To the physicists among the us, please share your opinion on the paper with the rest of us.

It's not easy to digest the paper. The finding is not only going to change finance, but also the whole data economy will speed up. Now 'Quants' can be located anywhere and everyone has can enjoy same advantage of datacenter-closeness, evening out the prestigious role of the select few. Well, not really. It's going to take quite some time until the mid-class can access this technology unless, someone finds out a way for mass-production. That would be stellar.

That's it. I hate nobody with a rational mind of whatever kind, but naysayers really itch me.

millstone11y ago

Luboš Motl reviewed it. http://motls.blogspot.com/2014/05/constructor-theory-deutsch...

He didn't like it, as if there were any doubt.

Jach11y ago

Not a physicist, but I don't think this is much to get excited about... There's no faster-than-light communication happening -- you'll note in the second paragraph that Alice must send the outcome of her measurement to Bob. It's a step towards impressive quantum computers, which will be cool to have so we can do things like Shor's algorithm or Grover's algorithm, but there's still a long way to go.

theduferOP11y ago

> Alice sends the outcome via a classical communication channel to Bob, who can then recover the original state by applying the corresponding local transformation.

This seems to be the key point - there is absolutely no FTL information transfer going on, which is pretty much what I expected. As I said before, it would've been much bigger news if there was. The press article was clearly written by someone who didn't understand what was going on (or was intentionally deceitful, but that seems unlikely).

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