Atmospheric conditions matter because you still have to send one photon of the entangled pair over the link. When air is still and clear between the islands, roughly one-in-thousand photons make it from La Palma to the receiver telscope in Tenerife. Available technology limits how much of this loss can be tolerated, and there are inefficiencies in other parts of the experiment as well. The whole experiment is indeed at the edge of what is possible with today's technology (which is one of the reasons it's published in Nature). But, you know, technology improves with time.

We transmit a quantum state, which is impossible to transmit via classical communication.

The auxiliary classical communication (about two bits per quantum state) has to be there, because faster-than-light communication is impossible. These classical bits carry no information about the quantum state being teleported. If one could teleport a quantum state without this auxiliary classical communication, faster-than-light communication could be implemented as well... which impossible in nature as far as we know.

I heard from Rupert Ursin that this is the longest free-space range on Earth that has significant infrastructure at both sides. This is to say, scientists can keep small optics labs in telescope buildings, and live in hotels. Also we had a 1 meter diameter telescope at the receiver station in Tenerife (normally used for optical communication with satellites), which is no small beast and it occupies its own dome. One could of course find many longer ranges between mountains, but logistics would become more expensive and difficult... we'd have to build and drive (or airlift) a container full of gear, and probably live in a tent for months.

Here is a picture of La Palma station sending a tracking beam to Tenerife, above clouds: http://www.vad1.com/lab/pictures/La-Palma-JKT-tracking-beam-4.jpg

By the way one doesn't get to clill out on beach very much. It's a long drive to the mountaintops where the observatories are situated. When I was there last April, we had snow in the mountains on both islands. I had, like, one day on beach and two weeks of night shifts in the labs. This still was a lot of fun :).

Did you check what spam filtering options are available at pair? The default could well be let your client filter, in your case Google, but you can change that to discard and play with the thresholds. Also make sure you switch on greylisting. However I agree that pair spam filter is not the best. It took me a while to set up, and the result in terms of false negatives and positives was still not perfect (though very close to that).

Second that. Have been a happy customer for 10+ years. Pair.com is not cheapest, but the uptime, stability and service (averaged over 10 years) are very good. Just email them and ask what they can do for you. I guess, your biggest cost with Pair will be bandwidth, but they have redundant connections and an extremely good uptime (I estimate 99.97%+). They are a trustworthy and very stable company.

Provide deep educational discounts, do a reasonable effort at protecting but not excessively much (because any technical protection will be cracked no matter what you do, it's a sport for tech kids out there), and finally don't freak about non-paying users... realise that they help you by making your software popular, and quite some of them will eventually pay, once they become heavy users and get in a position with funds available. Two cents from an academic user.

if a stage failed, the rocket would be remotely destroyed along with the crew

There was such thing on the STS (in case it badly veered off the course into America's populated areas during launch), but I've never heard of a remote destroy mechanism on Russian manned space launches. There is a remotely activated capsule rescue-and-landing sequence, though.

Something very wrong is currently happening within the Russian space industry

My theory is that between 1990 and about 2004, the Russian space industry lost and could hardly retain any yound engineers. As the result, it now lacks the most professional and mature 40-50 something space engineers who have energy to lead design projects. The few old workers who weathered the dark years are getting retired, while the last generation taken in the last few years hasn't yet got the experience.

So graze on, graze, you peaceful peoples!
You will not wake to honor’s call.
What need have herds for gifts of freedom?
They’re used to shears and butcher’s stall.

(Original in Russian here. Could not pass /. junk filter.)

Sigh. Four years ago, United Russia fraudulently got the 2/3 majority in the current parliament, in the same way, with all the same-looking statistics. This parliament passed, without a contest, some "nice" constitution changes (extending the presidential term from four to six years, extending the parliamentary term from four to five years). Now United Russia has a simple majority, by fraud. Yeah, these are "very minor inconsistencies not affecting the election outcome", as Putin has replied the protesters days ago.

It's easy to say "the party of crooks and thieves," but the problem that lets this happen is deeper... it's in the people, in the deeply rooted customs of the country.

Has any scientist in Canada disobeyed the 'official procedure' and talked to the journalists directly about his work? Or do they all follow the procedure, understandingly being very afraid of jeopardizing their positions and research grants prospects in Canada?

It is one of responsibilities of a publicly funded researcher (especially a tenured professor) to talk freely about his findings. This is an essential contribution of the publicly funded science to the society and democracy. I would thus seriously consider ignoring the orders in such situation, even at the risk of getting fired -- okay, it depends on the situation and how much is at stake, but I would at least think about this and probably discuss promptly with the university administration.

As far as I know, in other developed countries (including the one I am currently working in, Norway), there are no barriers in communication between scientists and the press. We answer emails and calls from journalists without asking anyone's permission. There is a public relations office at my university, but its purpose is to help the communication, not to censor.

Am I being too naive, or Canada is really abnormal in this respect?

Zero-knowledge authentication is impossible by definition. If you know nothing secret about someone, you can never verify his identity.

A small pre-shared key is used for initial authentication, in all classical and quantum crypto alike, to preclude a man-in-the-middle (MITM) attack. In the classical public-key infrastructure (PKI), this authentication key comes from the certicficate authority with, e.g., your copy of the web browser. If it is spoofed at the distribution step, MITM attack becomes possible.

In quantum crypto, the initial key is small, because once the quantum-generated key begins to grow, its small fraction is used for further authentication keys.

I'll bite this troll. I typed this submission because

1. I think what we do is cool, and is interesting to Slashdot readers (I read Slashdot daily myself).
2. I can formulate what we have done better and include most relevant links, comparing a random submitter who has just read a news story.
3. Yes! I am 37 and I do not nave a tenure yet! Every bit helps :). Unfortunately, really, I do not think anybody is going into science for money.

Currently the problem is quite general, because most quantum cryptosystems today use detectors of the vulnerable type. We think it is patchable, just not by the approach the Toshiba group practices, but patchable. (We dislike Toshiba's approach for not being general and thorough, but more of a quick band-aid.) During the past 20 years there were a couple problems of similar magnitude in quantum crypto, and they were solved. Note that similar problems periodically show in implementations of classical crypto.

The future of quantum crypto will now be decided, from one side, by the market, and from another side, by publicly disclosed mathematical developments on various classical ciphers (which can be cracked overnight, but can also be proven more secure... I'm not a mathematician so I won't venture a guess for the odds of either). In quantum cryptography there is at least one well-engineered commercial system, several advanced commercial prototypes (Toshiba has one), and the hacking efforts are going to eliminate all easy loopholes in a reasonable time. It is also important how well quantum cryptography can be meshed into networks with many nodes and links. There have been several demonstrations of quantum crypto networks, the latest in Japan last year.

The current commercial systems (like ID Quantique's Cerberis) use quantum cryptography as an extra security layer on top of classical crypto. To get to the master key used to encrypt the data, one needs to crack both quantum key distribution and classical key distribution at the same tme. We temporarily compromised the quantum layer in this work, but in a commercial installation the data security would hang on the classical crypto, until the quantum layer is patched. Of course the security of the symmetric ciphers (normally AES with frequent key changes) used for high-speed data encryption is another question, but I think there is also an option to establish a low-bandwidth highly-secure channel encrypted by one-time-pad. The whole reason AES is offered with quantum crypto is that the performance of the classical crypto has spoiled everybody, and the users do not want to separate communication into high-security and low-security categories. They just want to encrypt the whole 10 Gbps link, so this is the default option.

If the prof suggests you to submit a conference paper, he should cover the costs of your trip, period. This is reasonable and here is how it works in the academia: prof's name is in the author list > he has one more publication in his CV and his current grant report > when he's applying for a grant in the future, better chance to get it. For any decent grant, conference expenses are a footnote. Thus it definitely makes sense for the prof to fly you there if a publication comes out as the result.

As for your own sake, do this of course (if the prof or university pays). This is fun, useful, you get to see what a conference is like, will listen to talks on diverse topics and get stunned by how littlle you know and understand yet, etc. This is a good item on your CV too, except you should not pay for it (disclaimer: I am from socialist Europe.)