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Physicist Trying To Send a Signal Back In Time
phil reed writes "University of Washington physicist John Cramer is attempting to send a signal back through time."
From the article: "We're going to shoot an ultraviolet laser into a (special type of) crystal, and out will come two. lower-energy photons that are entangled," Cramer said.
For the first phase of the experiment, to be started early next year, they will look for evidence of signaling between the entangled photons. Finding that would, by itself, represent a stunning achievement. Ultimately, the UW scientists hope to test for retrocausality — evidence of a signal sent between photons backward in time.
The test will involve sending one of the photons down 10 miles of fiber optic cable, delaying it by 50 microseconds, then testing a quantum-mechanical aspect of the delayed photon. Due to quantum entanglement, the non-delayed photon would need to reflect the measurement made 50 microseconds later on the delayed photon. In order for this to happen, some kind of signal would need to be sent 50 microseconds back in time from the delayed photon to the non-delayed photon. (Confusing? Quantum physics is like that.)
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So this is how Bif gets rich. I knew there was no Sports Almanac.
If Bush wants to kill the terrorists, he should jump off a cliff.
Test has succeeded!
Yes, forget any of the laws of physics that might be violated here, the primary concern is this breaks the fundamental rule of the universe, the core axiom at the heart of space and time; it would allow people to cheat at the lottery.
You mean to tell me that it only just now occurred to someone to send an entangled photon through a spool of fiber and see how it affects its twin, which took a direct path?
Also, I thought entanglement couldn't be used to transmit information, as a consequence of Somebody or Another's Law.
Can anyone clarify just what this poorly-written and sensational article is actually saying?
No, this is Slashdot. You want real physicists, and you're probably barking up the wrong tree.
However you may receive several answers. They are statistically likely not to include the right answer to your question, but rather to fall into one of the following categories (in fact you may just get all of these):
1) Someone will pretend they know what they are talking about and give you a very long and detailed answer. Unfortunately it will be horribly wrong, but only people with the proper background will realize it (ie no one here). :D
2) Someone will post a completely offtopic ad hominem attack on you for no particular reason (brain hurt! must strike thing that make brain hurt!) for bonus it will probably have something to do with your sexual proclivities and/or your mother.
3) Someone will post a completely unrelated troll hoping to get people to actually read it.
4) Someone will post a smart-aleck comment predicting the reasons you will not receive your answer (Hi there!)
5) In Soviet Russia, ??? profits you!
640K won't be enough.
Gentoo Linux - another day, another USE flag.
This would be like posting a response before the initial post
And who says that can't be done?
This would be like posting a response before the initial post
You mean to tell me that it only just now occurred to someone to send an entangled photon through a spool of fiber and see how >it affects its twin, which took a direct path?
That's been done. I think the new thing here is that the photons are now outside of each other's light cone. Before with entanglement experiments the photons were still close enough to each other during the measurements that a naysayer could claim that when the first measurement was made a signal (traveling
Also, I thought entanglement couldn't be used to transmit information, as a consequence of Somebody or Another's Law.
Law of causality. If these systems could be used to transmit information, they could send information faster than the speed of light.
Can anyone clarify just what this poorly-written and sensational article is actually saying?
Take two entangled photons and send one really far away. Since it's known that measuring the state of the one far away will result in knowing what the state of the close one is one could claim
a) that the one far away sent an instantaneous signal to the close one, telling it what state to be in or
b) if you measure the close one first, that the one you sent away sent it's information from the 50 microsecond-in-the-future-measurement back in time to the moment you measured the close one.
I think the physicists working on this would say both of those interpretations are wrong.
I don't think it's possible though, otherwise we would probably be getting messages from the future, wouldn't we?
Maybe we're already getting them.
http://en.wikipedia.org/wiki/John_Titor
My site
Of course, in the clasical version of this experiment the crystal is usualy spherical with a diameter of about 20cm.
For Petes sake, we need 1.81jiggawats for this to happen.
And keep in mind, DO NOT CROSS THE STREAMS!!!
Why would you want to go back in time?
Going back in time would just mean you need to wait even longer for the Nintendo Wii to come out...
Don't marry her.
Okay two questions come to mind. First you have to the ability in the past to receive said message, and then you have to follow said message, and send it again. If you sent it via email it would mostly likely end up in your spam filter and lost to you. hence useless.
As the mesage would be filled with phrases like buy IBM on this date, short sell MSFT on this date buy it back on this date. Buy Apple on this date, etc.
i thought once I was found, but it was only a dream.
[past scientists] Hey future scientists, we totally got your message through the quantumly entangled photons you sent us!
[future scientists] (to past scientists, now present) You mean the message you sent us with the photons you sent into the future?
[past scientists] Awww maaan!
[future scientists] Yeah, causality's a mofo.
[past scientists] I wish we got invitations to the sorts of parties where the hostess's undergarments's wave functions were made to collapse 3 feet to the left.
[future scientists] can I borrow your hot cup of tea? I'm going to a party.
If you're going to have given people grammar advice, at least have done it correctly: you're using the the present ultraconditional subinverted sem-active past subjunctive deponent aorist, so that should have been "scrodding".
AH-HA!
That's what all the gibberish spam is! It's us sending ourselves messages from the future!
Of course, this means that in the future, we will all need giant penises and breasts to fight off the alien invaders, but we can finance the purchasing of the pills needed by buying penny stocks, consolidating our bills, and refinancing our homes... Of course, it also means that we will all be impotant, and need to purchase viagra in order to keep our species going...
It's all so clear to me now...
Nephilium
"Even on Central Avenue, not the quietest dressed street in the world, he looked about as inconspicuous as a tarantula on a slice of angel food." -- Farewell, My Lovely (Chapter 1)
We'll finally have an answer to the Grandfather paradox.
Volunteers reqiured for scientific experiment to redefine time as we know it. Lack of attachment to grandparents a plus.
Just because you're paranoid doesn't mean there isn't an invisible demon about to eat your face
Why is he looking for funding? It would be way more interesting if it was being funded by lottery winnings.
A lot of my spam comes from the future!
http://outcampaign.org/
WTF!!? I read that whole link and don't see anywhere in there about how to get my Free Wii. Don't post such lies anymore.
It's definitely possible to travel into the future in your own time line. In fact, it's pretty damn easy. I'll do it right now! Watch... ... ... ...
Voila, I'm in the future!
If you actually wanted me to travel "further" into the future, give me a spaceship that travels at 99.9999% of the speed of light and I'll see you in 1000 years. It's getting back that's the bitch.
Life would be easier if I had the source code.
The third states that there are infinitely parallel universes with every possibly outcome occurring simultaneously (string theory?) and that the universe has many more dimensions than three or four, possibly ten or more dimensions.
I don't think it implies that there is a universe for every possible outcome... Infinite universes doesn't imply every universe, just like an infinite set of real numbers between 1 and 2 doesn't necessarily contain 1.5.
At least I hope that's true.
I'd hate to think that no matter where I am, no matter what I'm doing, there's a parallel universe in which I'm mere moments away from being raped by a heard of goats.
Was that a bleat I just heard?
The enemies of Democracy are
We could open a IPoST (IP over spacetime) daemon on jan 1 2009, and be able to receive messages from the future from that date on.
Being spammed from the present is bad enough, but being spammed from the future....
Imagine making payments - it would be like Douglas Adams's "Restaurant at the End of the Universe" - Just open a bank account under our name with a minimum deposit, and rest assured, your visit will have been fully paid from the accumulated interest over several billion years.
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