Slashdot Mirror
First Bank Transfer via Quantum Cryptography
An anonymous reader writes with today's announcement that "the Austrian project for Quantum Cryptography made the world's first Bank Transfer via Quantum Cryptography Based on Entangled Photons; see also Einstein-Podolski-Rosen Paradoxon." (For more background, see the recent Slashdot post "Quantum Cryptography Leaving the Lab.")
Yes, but... what will I now need to decode my bank statements?
Wouldn't checking if the transfer went through alter your balance? :-P
...I can't observe my checking account balance without lowering it.
So the transaction slip presumably says:
Your transaction number has a 90% probability of being between 8765432 and 8765478.
Have a 75% nice day.
Craig Steffen
http://www.craigsteffen.net
'Entangled' and 'money transfer' might become interesting when more than one person tries to do a money transfer at the same time...
An acutal real world example! Excellent
Go Gusties
That is all.
Due to Insufficient Cat.
... there has been a bank error in your favour. Collect $200. :)
..but why do we need this?
The biggest hole in security is usually the people operating technology. Ever want something, call up and ask for it.
What does the ability to have uncrackable encryption do to thwart social engineering tactics?
SIGERR: laziness exceeds quota
Was for +/- $100i
Thank you for your patronage.
Presumably, opening an account with this bank will get one "shrodinger's cat" as a new account premium?
Sure but would they still charge a fee for using "out of our network" ATMs?
N:T:
I'll give you my entangled photons in exchange for chocolate.
"If you think you have things under control, you're not going fast enough." --Mario Andretti
At the University concluded a study which finds quantum cryptography is a lot better than plain cryptography. Please FAX bank account via quantum cryptography to KWEISE MFUME at +34 79 345 8792 for full article.
Looking forward to hearing,
Letter
are only good for small change...
MP3 Search Engine
Man arrested in connection with bank transfer fraud, he reportedly stole 1.2 million dollars using a flashlight
Thats some damn complicated stuff, there! I hope the technicians who fix the ATM machine know about phuton criptography. I may know how to program with code, but damned if i know how futons work!
http://github.com/gbook/nidb
Once again, I point out that there is no such thing as quantum cryptography. It's a lie perpetuated by idiots and charlatans. All quantum "cryptography" systems require a conventional message authentication code. The whole system is no stronger than that MAC*.
*Well, against a well-funded adversary. But then, Jim Bob's House of Cryptanalysis and Live Bait isn't going to try cracking the high-end security needs these systems are shilled for.
I'm asking this question again because it came a bit to late to the last discussion I posted it in
.1 photon to reduce the probability of generating a two-photon pulse that could be split and eavesdropped undetectably."
Is quantum crypto provably flawed?
I've seen tons of blurbs stating the the link is "absolutely" secure, but it seems that isn't really the case. (see the bottom of the page.)
What strikes me about all this is the following section:
"each pulse should be attenuated to an average of about
What that says to me is that there is not way to 100% know you're transmitting just one photon.
It sounds like there's no device that is capable of transmitting one and only one photon with 100% reliability. If this is the case, a lot of the arguments about how secure this is are vastly overstated.
In the end QC would be vulnerable to a man-in-the-middle attack by watching for multi-photon emissions.
If this is the case, a lot of the noise surrounding QC could turn out to be hype. (The big plus for quantum crypto is that it's supposedly immune to this.) Is there a quantum physicist in the house?
Life is too short to proofread.
Gates Account, holding his several billion dollars, is the only account in this database to take up ALMOST 5 MICROMETERS OF SPACE!!!!
ph33r teh $$$ !!!
Nah, back to those good ol' electrons.
So then the money has been both transfered and not transfered? That sounds like an argument waiting to happen.
"Have you ever thought about just turning off the TV, sitting down with your kids, and hitting them?"
What I don't understand is why can't you cut the line and put in something like a repeater. When you read a bit, you change that photon, but then you just transmit a clean one with the same value (or maybe even change it to confuse).
-I am an elective eunuch.
Are current encryption schemes crackable?
Bruce Schneier covered why quantum cryptography doesn't solve any security/secrecy problems in his December 15, 2003 Crypto-Gram.
"It's like defending yourself against an approaching attacker by putting a huge stake in the ground. It's useless to argue about whether the stake should be fifty feet tall or a hundred feet tall, because the attacker is going to go around it. Even quantum cryptography doesn't "solve" all of cryptography: the keys are exchanged with photons, but a conventional mathematical algorithm takes over for the actual encryption."
... i'm not 'certain' - have you asked mr. heisenberg?
Is this instantaneous? Wouldn't that violate the whole speed-o-light thing?
They say the first thing to go is your penis. Well, it's either that or your brain. I forget which...
The reason that the man-in-the-middle attack doesn't work is that by doing so, you introduce two sets of attenuation rather than one. If the message is intercepted and then re-transmitted, the message has now been sent through the attenuation cycle twice. This means that instead of the signal being modified by the original attenuation function, it's modified by the attenuation function squared, which is easy to distinguish.
Craig Steffen
http://www.craigsteffen.net
My knowledge of cryptography is limited to the entry level college course of which I remember quite little, and my knowledge of physics is as limited as it can be.
To me this story is rather sensational -- I didn't realize that quantum crypto is that close to actually being used; it also seems to me that wide use of quantum crypto is going to revolutionalize the field.
Can someone who knows a lot about this explain to the rest of us: is this "WOW!!!" or just "neat!"?
I passed the Turing test.
This is a solution to a different problem. Inventing a more effective toothbrush won't get kids to brush their teeth either, but who cares?
~Berj
Call the producers of Quantum Leap!!
The more accurately you know how much money to send, the less you know about where to send the money.
Yeah, but filling out the slip for "1/sqrt(2) |deposit> - i/sqrt(2) |withdrawal>" is a pain, and thanks to the epoch of inflation my balance is now much smaller than the rest of the universe... luckily, even in an income vacuum my balance randomly jumps up, but only for REEEEAAALLLLYY short lengths of time. I've been hawking radiation for a while but everyone says it's just a two slit operation.
Okay, I'm done now.
[TMB]
Otherwise the money will go to other accounts due to tunnel effect.
/nova20
I remember reading a book all about the history of cryptography. It outlined the evolution of cryptograpy from simple albhabet substitutions to the concept of quantum cryptography. It shows all the pros and cons and weighs them against eachother.
Excelent read for anyone interested in the field or just currious about it.
ISBN: 0385495315
the lights get turned off, where does all my money go?
presmike
As I understand it (according to Bill Bryson's "A Short History of Nearly Everything") entangelment does in fact violate Einsteins theory. It says that two entangled photons at any distance apart from each other will react identically instantaneously. **Notice** Instantaneously! That is faster than the speed of light. Einstein did not believe that this was possible, but experiments have shown this to be true, at least as we understand it. The part that impresses me the most is that someone devised a logic experiment that could determine the results with near certainty without altering the results. An excellent source for more information is the book "Mind at Light Speed", I forget the author's name. "A Short History of Nearly Everything" is also a great book which covers so many topics that it made my head spin.
Why doesn't anything interesting happen when I have mod points?
So it's really about social-engineering potential customers.
Bill Stewart
New Fast-Compression-only CPR http://preview.tinyurl.com/dy575ks
http://www.cs.dartmouth.edu/~jford/crypto.html shows what I was thinking of. Look to number 6. The key is pretending to be the other to both sender and reciever.
-I am an elective eunuch.
first Bank Transfer via Quantum Cryptography Based on Entangled Photons
I would expect transfering some data would be pretty ok, but they entangled and transfered a bank? Unbelievable. Did some bank office clerks survive their quantum encryption?
There you are, staring at me again.
Incorrect. It has simply proven uncrackable to date with the current technology and understanding of the universe we have. (Makes me think of idiots who have never had a hacker crack their system, so they brag about their system being uncrackable and list their address. Suddenly, they've got cracks all over.)
I was taking one day at a time, but then several days got together and ambushed me. (from a Rhymes with Orange comic)
You can simulate this probabalistic balance behavior right now by getting married and getting a joint checking account.
Erik
YOU ARE SAYING IMPUDENCE TO ME! THAT IS IMPUDENCE!
Anyone that takes Crichton's Physics seriously should be transported to another multiverse
"There is no teacher but the enemy."-Mazer Rackham
19AA3 F5440 97529 89DA2 9C4C9 48E9D 96978 79E44 95968 4938D 8D828 C3B3A 8D8C8 C8984 86757 B7276 2F2E8 08574 57292 86A27 6E7B7 37170 57
May the Maths Be with you!
From The Straight Dope
Schroedinger, Erwin! Professor of physics!
Wrote daring equations! Confounded his critics!
(Not bad, eh? Don't worry. This part of the verse
Starts off pretty good, but it gets a lot worse.)
Win saw that the theory that Newton'd invented
By Einstein's discov'ries had been badly dented.
What now? wailed his colleagues. Said Erwin, "Don't panic,
No grease monkey I, but a quantum mechanic.
Consider electrons. Now, these teeny articles
Are sometimes like waves, and then sometimes like particles.
If that's not confusing, the nuclear dance
Of electrons and suchlike is governed by chance!
No sweat, though--my theory permits us to judge
Where some of 'em is and the rest of 'em was."
Not everyone bought this. It threatened to wreck
The comforting linkage of cause and effect.
E'en Einstein had doubts, and so Schroedinger tried
To tell him what quantum mechanics implied.
Said Win to Al, "Brother, suppose we've a cat,
And inside a tube we have put that cat at--
Along with a solitaire deck and some Fritos,
A bottle of Night Train, a couple mosquitoes
(Or something else rhyming) and, oh, if you got 'em,
One vial prussic acid, one decaying ottom
Or atom--whatever--but when it emits,
A trigger device blasts the vial into bits
Which snuffs our poor kitty. The odds of this crime
Are 50 to 50 per hour each time.
The cylinder's sealed. The hour's passed away. Is
Our pussy still purring--or pushing up daisies?
Now, you'd say the cat either lives or it don't
But quantum mechanics is stubborn and won't.
Statistically speaking, the cat (goes the joke),
Is half a cat breathing and half a cat croaked.
To some this may seem a ridiculous split,
But quantum mechanics must answer, "Tough @#&!
We may not know much, but one thing's fo' sho':
There's things in the cosmos that we cannot know.
Shine light on electrons--you'll cause them to swerve.
The act of observing disturbs the observed--
Which ruins your test. But then if there's no testing
To see if a particle's moving or resting
Why try to conjecture? Pure useless endeavor!
We know probability--certainty, never.'
The effect of this notion? I very much fear
'Twill make doubtful all things that were formerly clear.
Till soon the cat doctors will say in reports,
"We've just flipped a coin and we've learned he's a corpse."'
So saith Herr Erwin. Quoth Albert, "You're nuts.
God doesn't play dice with the universe, putz.
I'll prove it!" he said, and the Lord knows he tried--
In vain--until fin'ly he more or less died.
Win spoke at the funeral: "Listen, dear friends,
Sweet Al was my buddy. I must make amends.
Though he doubted my theory, I'll say of this saint:
Ten-to-one he's in heaven--but five bucks says he ain't."
--CECIL ADAMS
First, Schneier really loves his stake-in-the-ground idea. He used it to describe cryptography in general in his "Secrets and Lies" book (which, IMHO, doesn't hold a candle to the quality of his applied crypto books. In fact, it feels more like a book-long commercial for his managed security business)
Anyway, sure. QC alone ain't gonna help you. But if it's a stake in a ground that's part of a fence, it damn well matters if it's 100 ft tall vs 1 ft tall, or even 10 ft tall.
Does it 'solve' security problems? No, of course not, because as many many many people have already said, in this post and in many other places, the way to defeat the best crypto in the world is to look under a keyboard and copy down the relevant password/phrase that the user wrote on a sticky-note there. (or other social engineering tricks)
It does make security easier, as it prevents MITM attacks, requires (for now) specialized hardware, and provides really-tough-to-decode crypto. So, if you have the rest of your process working, yes, QC can help by being a more secure technology.
But think of the inverse. OK, so, crypto is like a stake in the ground, it doesn't matter what size or where it is. So, let's all use DES, because it's an established standard!
You are only as secure as your weakest link, obviously. You'd be stupid if crypto turns out to be your weakest link, as even not counting QC, there's lots of good, secure crypto processes available.
Returned Peace Corps IT Volunteer
The encryption works:
> cat balance
cat: cannot open balance
After spending an hour in the wikepedia I have concluded that this is all just hype. Quantum Cryptography is still only theoretically encrypted. It has not been proven yet because quantum mechanics is not fully understood yet.
Furthermore, this is really just a Quantum Key exchange. So tack on whatever protocol you wish to use once you have the key. Quantum encryption is something that would require quantum computing first.
Also please note, the quantum transmission is not even "secure." Its just that if anyone but you reads it, you are secure in the knowledge that you will know about it.
At least this is what I have understood. Still hype. Notwithstanding, as science this is probably an advancement. Its just not what its being marketed as.
If this method is secure from end to end, and taps are detectable, it clashes with Governments demanding the ability to wiretap at will. Only the people that should be watched will be unwatchable? Banks are notoriously corrupt when large transactions are going from big gangstercorporation to big gangstercorporation.
Don't look to closely at your account balances, lest they become more uncertain.
in cryptography! :-)
This is really amazing; think of the possibilities that this offers. If this sort of system gets affordable, mass-produced and hits the market, it will invoke a whole new era of communication!
Gone are the hackers who snif out passwords and creditcardnumbers; the moment they try to intercept it, it is discovered. Brute force attacks become meaningless, since the key is generated completely at random and is of a one-path nature, which is theoretically proven to be unbreakable (in contrast with every ordinary assymetric - and most symmetric - encryption used today on the Net).
An those old encryption methods and mathimatical formula's *will* become obsolete, by that very same thing: quantum mechanics. It's no secret that a lot of people (especially in the military branche) are working hard to create a quantum-computer capable of breaking any currently existing encryption in mere minutes.
So, by the time this quantum-encrytion hits the consumer, we'll need it!
--- "To pee or not to pee, that is the question." ---
Did they impliment this using the BB84 or B92 protocal? The BB84 is very simple but the B92 is much more secure. As with all things, "perfectly secure" in theory does not necesarily mean "perfectly secure" in the real world and BB84 is more seceptible than B92.
I do security
It look to me like you could use a beam splitter to defeat this--unless it is a single photon, in which case I don't understand how you don't loose lots of data. Also, both the transmission point and the end point need to know what the polarization is going to be before hand...if you know that, why not just use that sequence as your encription key?
This principle is generally true in classical economic transfers as well: Bill Gates keeps having lots of money, but I only sometimes have money; I know I owe lots of money to my bank for student loans, but I only have a suspicion that my friend owes me 50 cents.
Erik
YOU ARE SAYING IMPUDENCE TO ME! THAT IS IMPUDENCE!
An interesting theory trying to explain this seemingly inexplicable result, is by taking the hypothetical possibility that the bands are created by photons that exceed the speed of light. Only when they revert to another (visible) quantummechanical state (by hitting the wall, for instance) do they become noticable.
This is not impossible, because, contrary to what most ppl think, lightspeed is in fact an average; within one beam, there can be photons that are moving slightly slower, and photons that move slightly faster then the speed of light.
This, however, leads to the conclusion that those particular photons come from - at least potentially - another time or space. So, the film 'paycheck' might not be complete bullocks after all (though it's doubtfull we are ever going to be able to create a usefull 'time-viewing' tool out of it).
Then again, never say never, as Bill Gates with his '640K is enough for everyone' can vow.
The theory about another 'space', in contrast, leads us to the possibility that those photons actually come from parallell universes. It seems SF, but it are, in effect, valid scientific hypotheses which deserve further investigation.
After all, apart from these theories, there *is* no explication for the result of that experiment.
--- "To pee or not to pee, that is the question." ---
It will be cool one day, imagining that for a brief moment, the photons, being in a superposition of states, *could* be transferring all the known wealth of the universe to my bank account. Sadly, when observed, minus service fees, it's probably only like a buck-fifty.
Anybody want a peanut?
BUT, the post is still offtopic with regards to the STORY, which is the point. It may be more usefull if all responses to offtopic posts inheireted the offtopic moderation, since, naturally, they are also off topic.
BUT the beauty of Slashdot comments is that you never know what tangents are gonna shoot off from a topic of discussion. Say in a story about programmer salaries someone mentions about a really bad job they had once and someone replies saying 'Oh yeah I worked there too, my female boss was a real bitch' and a little conversation thread continues, why should the posters fear the all mighty OT mod and post anonymously when they are replying to a post and not creating a new thread? It's not like they have to be modded up or anything, but off shoot threads are hardly obstructing people's Slashdot reading times
There are also times when offtopic is used instead of troll or flamebait, which is wrong. Is offtopic the first type of moderation in the list or something?
Simple: fold the futon up when you want to use it as a couch and then fold it back down when you want to use it as a bed.
But at night you can't tell what state the futon is in, without at first knowing where it is.
This is known in Quantum Mechanics as Schrodinger's Crib experiment.
So what is new here? ;)
Yes, Quantum Cryptographic Communications (QCC) can help with the requirement that the one-time pad must be transmitted in private. However the one-time pad cannot be reused so your key must be the same size as your text. Thus far, Quantum Cryptographic Communications is not a speedy high bandwidth form of communication. It might be OK to transmit a small key but to date it is not OK for sending, in a reasonable period of time, huge one-time pad keys that are as big as your original message.
Another thing people sometimes gloss over about Vernam one-time pads is that your cipher is only as good as your random number generator! If you generate your one-time pad using the v7 libc rand(3) function your one-time pad is next to useless.
Another important aspect of Quantum Cryptography (Quantum Cryptography is not simply limited to communications) is random number generation. Quantum Cryptographic Random Number Generation (QCRNG) is a useful tool in generating keys (one-time pads, block cypher keys, public/private key pairs, etc.).
The importance of QCRNG goes beyond Vernam one-time pads. You want a cryptographically strong RNG such as a QCRNG when you generate your session keys. Sending predictable keys over a QCC protected link is next to useless!
Now IF you have:
then you will begin to approach the ''unbreakable cypher level'' that some people think you get with Vernam One-Time Pad Ciphers.
chongo (was here)
OK, I am not a believer in quantum cryptography for one big reason -- fiber loss. Someone please enlighten me if I'm wrong.
The loss of standard single-mode fiber is about 0.1-0.2 dB/km. Therefore, unless the distance is short (as in this demonstration), the transmitter must send multiple photons to ensure a decent probability of providing the receiver with one photon.
For example, if the span is 100 km long (20 dB loss), then on average only 1 out of every 100 transmitted photons will reach the receiver.
The situation is worse for autocompensating quantum-crypto systems (e.g., polarization-based encoding), because the photons must survive a round trip through the fiber.
Therefore, the relatively high power at the transmitter implies that an attacker can tap into the fiber near the transmitter, subtract (on average) only 1 photon, and remain undetected by the receiver.
Furthermore, typical optical amplifiers add noise (3 dB noise figure for your standard erbium-doped amplifier). The added noise photons would screw up the link, so amplifiers are out.
In the end, it seems to me that quantum crypto is good for table-top demos, and maybe for short jaunts across a metro area. But it is NOT absolutely perfect, at which point computationally difficult encryption is more attractive.
Now someone can be both Miriam Abacha AND Sese-Seko in their 419 scams at the same time!
For your security, this post has been encrypted with ROT-13, twice.
Here, let me quote the bit that explain how the man in the middle attack can succeed:
We're not allowed to export some of the mainstream encryption out there for national security reasons... So does this mean that, Australian or not, if a US individual or company exports this technology themselves, they get the thumbscrews?
Do not confuse "Freedom of Choice" with "Free Will".
I'll laugh if the back-end were an unpatches windows 2000 running an unpatched MS Sql server...
- Sam
I'm sure they incorporate current crypto. Its just the last step is over the quantum crypto. So, even if one manages to man in the middle a photon or two its going to be jibberish. And even after you find out its encrpyted jibberish they "know" because you cannot reporduce an entangled photon.
Ya, stealing passwords, pilot error, spyware on computers are always going to be a problem. But we are talking about the "tech" part of the problem here. So, lets not resort to a cop out.
Do a perfectly secure transaction with quantum cryptography and then tell the whole world about it. That's like walking a tightrope then jumping off the platform on the end.
using quantum mirrors, you could possibly split the light stream into two separate streams without altering the quantum state, and get perfect copy of the data real time
There are no atheists when recovering from tape backup.
You're missing the point here... Quantum cryptography _creates_ a set of 1 time pads that both the sender and receiver have. So, a fairly small one-time pad is generated, and then the data is encoded & transmitted over a fast line. This is why it's often referred to as QKD (quantum key distribution). For absolute security, you only send data encrypted directly with your key, which is slow, but can't be decoded by a 3rd party.
The problem with this is not that it doesn't 'solve' any security problems, but that it does not do anything that is not already done well enough and cheaper using conventional methods.
I can already perform a transaction with my bank's server without anyone being able to eavesdrop or perform man-in-the-middle attacks or modify the transaction. SSL works, nobody has the technology today to crack 128 bit codes, and cryptographically strong pseudo-random number generators seeded with proper care are no less secure in practice than random numbers generated using physical quantum processes.
I can perform that secure transaction to my bank without having a special use untappable optical fiber cable installed between my house and the bank. What extra security would I get for the cost of the fiber and the quantum cryptography equipment? Protection from some mythical person who can crack AES or RSA?
The stake in the ground analogy has to do with concentrating on only one aspect of security while ignoring the rest. If you look at the whole picture, yes, the protection of the transmission line is one post in a fence rather than an isolated stake in the ground. At that point you can make sure that the post is not one foot high (like using DES for the crypto) but it may be that having it 10 feet high (AES/RSA) makes the fence strong enough and building it 100 feet high (QC over dedicated fiber) is just a foolish unnecessary expense.
Quantum cryptography is not at all the same thing as quantum computing. The former is just a very expensive way to make sure someone doesn't tap your line, something which can be done much more easily using SSL or SSH or any other VPN technology.
They want their disproven 'ether' theory back.
The quantum state of the particles IS the random number generator. You aren't using a software RNG to feed the quantum device, you're relying on the inherently random nature of quantum fluctuations to Create your random data.
This, my friend, is as random as it gets, until someone develops the Theory Of Everything.
I'd happily swim to the bahamas. even from here on the west coast.
Geek license firmly stapled to my wallet, I was always good in physics but could not hold a lecture on quantum theory. are you actually sending the particle or using the information on where the particle problably is at that moment as the key? I bow my head in shame :-S
I believe you are approaching this topic all wrong:
The Vernam Cipher, or one-time pad is not a the ''super-duper unbreakable solves all your problems'' cipher that some people think it is.
Yes, the Vernam cipher is unbreakable, because the cipher itself requires all of the things you mention. You talk about random keys as if they might be optional, but they are actually standard necessities. It is a subtle difference, but I hope you can see it. If someone misuses the Vernam cipher, it becomes crackable, but in its nature, it is super-duper unbreakable solve all your problems.
Why would you fear OT? I just post anyways. If you have an account you get notified of replys and such, so you can easily follow the thread.
since there is no (QC) authentication, so you are not *securely* transferring anything. Moreover, even if there was authentication, only a fraction of the data is assumed confidential. To get a key stream, you have to apply a classical hash, but leaking a portion of a one time pad leaks data, so the whole system is as secure as the classical crypto hash and the classical means of authenticating whoever you are sending the key stream to in the first place. Snake oil (so far.)
When in doubt, have a man come through a door with a gun in his hand.
It's an interesting way to exchange keys, but does this have any practical use in the field of cryptography? We can already exchange keys very securely, and can do it quickly over any communication medium.
All you need is for some man in the middle to tap the line before you've finished hooking it all up and tested the line conditions, and you probably won't be able to detect it at that point.
Given this information, which do you think would have a greater impact here on Earth... Being able to drive that Mars rover in real-time, or being able to deduct 20 bucks from the ATM with a new kind of encryption? Oh, the White House has a bigger budget than NASA? Nevermind <sigh />
But quantum crypto doesn't prevent man in the middle attacks, it only prevents evesdropping.
The only thing quantum crypto gives you is knowledge that the guy at the other end of the line is the only guy getting your message, it doesn't tell you who that person is, or even where the other end of the line is - someone could have cut the cable and set themselves up as 'the other end'.
So quantum crypto falls back on traditional crypto to establish who is at the other end, making it as mathematically weak as conventional crypto but needing special infrastructure.
I dunno why you got a zero for that remark, but actually you are right. I've mentionned it in my post too, and there I got a 4, so I dunno how the moderating-system works around here :-).
There *is*, in fact, a theory that tries to explain it by the hypothesis of parallel universes.
--- "To pee or not to pee, that is the question." ---
I'd suggest that you spend a little bit of time looking up Neural Nets and AI a little bit. I spent a little time a while back trying to find more information about these topics combined, and it ended up with a couple of pages that said essentially:
"We decided to try some of these techniques in trying to work with the stock market. Since we have made so much money from that, we are unwilling to disclose the exact techniques and have closed this line of research."
Or something to that effect.
If this has real world applications as you are sort of suggesting, it is very possible for these folks to start making huge piles of money... together with some financially savvy people who will make even more off of them (the physicists). The only suspicion that you should have is if they made a real breakthrough but are not telling anybody else in the world as well.
So how is this different than EPR pardox?:
Pull the four aces out of a deck of cards. Don't look at them. Give any 3 of them to a friend and keep one. Send the friend on a 2000 mile plane trip. Nobody knows which 3 cards the friend has. They could be any of the aces. After the friend reaches his destination, look at your card. It's the ace of spades, for example. You instantly know that the friend's 3 cards are the aces of diamonds, hearts, and clubs.
Author taps tinfoil hat.
If you like TEU, I recommend the book I'm reading now, Brian Greene's latest - "The Fabric of the Cosmos".
I had the good fortune of hearing Brian talk about the book at a book signing. He discussed the implications of string theory and the EPR paradox at length which suggests that the book will have shed some light on the subject. (I haven't gotten that far yet)
There is also a great discussion of the arrow of time in the book, something I find fascinating.
In our case we used a sodium lamp in high-school for Young's slit experiment. The idea was that it was monochromatic and several orders of magnitude cheaper than a low-end laser in those days. The slits weren't that small.
See my journal, I write things there
I was interested in how they generated the entangled photon pairs, so I googled and came up with an interesting paper that touches on the subject:
"The entangled photon pairs created by Kwiat's team are produced using two thin, nonlinear optical crystals to split the "parent" photons from a laser into entangled "daughter" photons. In previous research at Los Alamos, these entangled photons have been used for quantum cryptography to create unbreakable cryptographic keys that can be used to lock or unlock encrypted messages.
Decoherence is a problem in quantum systems because the fragile quantum superpositions of entangled states are destroyed by unwanted coupling to the environment through which the photons are passing. Decoherence in Kwiat's system is intentionally created by passing the entangled photons through a roughly 10 millimeter piece of quartz. This optical environment produces a collective decoherence in the photons where one particular entangled photon state is, as predicted by quantum theory, essentially decoherence-free. These photons could serve as the basis of information carriers for quantum communications."
I'm getting tired of this 'no way, josé' thingy.
While not an absolute fact (there never is, in science), the concept of faster-then-light photons is *not* ridiculed or disregarded by physicists.
For instance, Professor Feynman is a distinguished physicist who has explained the theory behind it many times. (He is also a member of the American Physical Society, the American Association for the Advancement of Science; the National Academy of Science; in 1965 he was elected a foreign member of the Royal Society, London (Great Britain)...)
I know it's a deeply believed dogma that nothing can go faster then light, but, for quantummechanical particles, the data suggests it *is* possible.
--- "To pee or not to pee, that is the question." ---
I didn't know you were argumenting semantics. I try to avoid that, since it never leads to anything constructive.
For all normal purposes in this discussion, the 'speed of light' is regarded as a constant. Otherwise, playing semantics, this leads to meaningless statements. For instance; what if another quantum-particle achieves faster-then-light speed, even if it ain't a photon? Using semantics, I could argue that it's not exceeding the speed of light at all, because it's not a photon.
The whole thing would become stranded in the absurdity of pedantic semantic definitions.
--- "To pee or not to pee, that is the question." ---
Errr... how does making photons go faster explain the fact that you get the same result if you send the photons one at a time? Which is the spooky essence of the experiment, after all.
I read it in some science book or magazine years ago, but since I'm no physicist myself, I'm not going to debate it endlessly.
;-)
As far as I can remember it also covered light in a vacuum, since in a medium where light is slowed down, it's not very farfetched and rather obvious to expect it is possible for photons to be faster *in that medium*.
I think the theory was, that particles with no mass and with the speed of light (or subatomic particles very close to the speed of light) might make a 'quantum-jump' and go faster then light. Nothing prohibits something going faster then light, as far as I recall, just reaching that point is deemed impossible. But for quantummechanical particles you have a possibility thanks to the strange laws governing there.
Well, whatever, if you say it's absolutely impossible, I'll bow to your wisdom!
--- "To pee or not to pee, that is the question." ---
If your concern is your bank balance, then where the money actually is is neither here nor there. :-)
My other car is a 1984 Nark Avenger.
With the double slit scheme you don't need a coherent light source (the 2 slits work as 2 in-phase light sources). The slits (both their thickness and distance) need to be (loosely) the wavelenght size (that meaning, with visible light, you need special slits made in film; you can do one with photographical methods I suppose, or buy one (easier :) ). If you wan't to "see" the effect happen, maybe you should try with waterwaves.
The fourier transform property is used widely, and you can do amazing stuff simply with carefully painted films, like filter-out low space frequencies to have just the high-freq details etc (more commonly used to clean noise).