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Here (PDF warning) is an in depth look at high temperature superconductors, especially the cuprate families, for those not well versed in the subject.

How nearsighted of them ;) No support for PPC64 at all? I even tried building Wine on an 8-way POWER5 machine to run the Windows 32-bit binary under, and that didn't work either.

So how about it? When will we see a PPC/PPC64 Linux binary of Folding@Home? Where is the source, Luke? I'll build it myself!

Macro Lens, Directional Antenna (http://www.seattlewireless.net/index.cgi/Pringles Cantenna), Explode the top off with Liquid Nitrogen (http://www.physik.uni-augsburg.de/~ubws/nitrogen. html) and some prefer to use it in the event they need to use the restroom and facilities are not available (http://www.emericaskate.com/more/parisbarca/). I tell ya, I'd like to know what that can with the delicious potato chips CAN'T do.

What if I don't have access to a LinuxPPC64 machine to do a port?

There are community-based LinuxPPC64 machines available.
The University of Portland School of Engineering. Please see: http://www.egr.up.edu to register for an account
The University of Augsburg (Germany). Please see: http://tuxppc.rz.uni-augsburg.de to register for an account.
Apple Power Mac G5s are based on an IBM processor and work fine for porting activities as do many of the newer G4-based systems.

CPU cooling - among other things - is done by liquid nitrogen.

wouldn't it be nicer to name your inc variables xxx ? ... it's fun!

Which reminds me of my favourite sites to visit when my internet access is through monitored firewalls (corporate or university systems)

http://xxx.lanl.gov/
http://xxx.arxiv.cornell.edu/
http://xxx.adelaide.edu.au/
http://xxx.uni-augsburg.de/

Yep, folks - Governments and Universities worldwide, hosting xxx sites. And for what it's worth, xxx.lanl.gov was the original!

http://xxx.uni-augsburg.de/abs/astro-ph/0403597

Shows you that you really need to know what you are talking about if you want to make an intelligent comment about this paper.

The problem with claiming Einstein as a misunderstood genius from outside the scientific establishment is that his ideas were widely and rapidly accepted by the scientific mainstream. Examine the famous 1905 volumes 17-18 of Annalen der Physik: many people feel that any of the four unrelated papers Einstein published in these volumes would have been sufficient to net him a Nobel Prize.

Clearly, special relativity was the most controversial of the four ideas, but it was taken seriously enough that immediate plans were made to test its predictions. It is true that there was much argument about the validity of special relativity, but this argument actually tended to be mostly among the less distinguished scientists and "science popularizers".

This whole line of development is in sharp contrast to Lynds, who as far as I know has not proposed a testable scientific theory that makes realistic predictions. If he were to do so on such an important subject as the flow of time, and if his theory made sense, I feel pretty confident that the theory would be widely publicized, and the tests quickly performed.

1001 things to do with liquid nitrogen.

No... quantum computing will not allow you to factor in constant time or anything, or by "assuming the answer", get back the factors. Your idea seems to be "let's take the result and then calculate backwards" so to speak. But that won't work. Now if we could create two superpositions of "all numbers between 0 and sqrt(c)" (to put it in an easy way), calculate the product and then find a way to filter out all results equal to c (which seems to be what you're looking for), then we'd of course be able to simply measure the factors. But the problem is that you can't "filter out" only the results you want to look at. You might be able to slightly increase the likelihood of measuring the 'correct c' and therefore getting correct factors. That's (very simply put) what Shor's algorithm is doing - it only manages to increase the likelihood to measure the right result and therefore retrieve correct factors.

Note that I'm grossly oversimplifying...

Another example is trying to solve 3CNF-SAT - figure out whether a formula in 3CNF can be satisfied - in O(1). Classically, it's an NP-complete problem with exponential complexity. Now the naïve attempt would be to create a superposition of all possible inputs, filter out only those that yield "true" as a result, and then measure the "filtered" superposition to get a solution. Same problem; you can't really filter out the "true" results, you can only make it slightly more likely to measure a "1" as a result and therefore retrieve a solution for the input. You'd still need to repeat that for a couple of times, only less often as in the classical case - but still not in O(1), or even O(n).

So no, quantum computing is not that much of a magic solve-everything-instantly machine... e.g. Grover's algorithm to find an element in an unsorted list will not bring you from classical O(n) to O(1), but rather O(sqrt(n)).

But then again, maybe you're just trolling :)

Anyway, I found this paper here very interesting: it's called "Quantum Computing for Non-Physicists".

The informative bit is the reference 7 where stochastic resonance is actually explained.

stochastic resonance

Quantum Cryptogrpaphy, or maybe better Quantum Key Distribution (QKD), is already much more advanced than many people think: there are already groups working on devices that might become really small and cheap in a few years from now.

These devices allow their users to establish a secure key, which might be used as a one-time pad. Secure means in this context, that any eavesdropping strategy allowed by the laws of physics can be detected, and, to some extend, corrected. The latter means that even tough an eavesdropper might have gained partial information on the key, Alice and Bob can amplify the security of that key by (essentially) discarding some of the key bits. This method also helps against the "noise-introduced-by-the-channel-cannot-be-disting uished-from-an-eavesdropper" - issue.

However, all those devices for practical QKD have two problems: Absorbtion and decoherence. Both scale exponentially with the length of the quantum channel used. This is the reason why with current technology it is difficult to go to distances between Alice and Bob which are larger than, say, 100 km.

In order to help against these difficulties (which prevent you from going to large distances in QKD), there are two solutions known (at least, to me): the first is of rather theoretical use: Quantum communication can be thought of as a (rather trivial) special case or quantum computation, and for quantum computation there are codes known (so-called concatenated codes) which allow you to to continue your quantum calculation with polynomial cost. This solution, while elegant from a theoretical point of view, has the disadvantage, that quantum communication becomes techically as difficult as fault-tolerant quantum computation.

The second is the so-called quantum repeater (see http://xxx.uni-augsburg.de/abs/quant-ph/9808065 and the references there in). The quantum repeater is based on entanglement purification and entanglement swapping. Now, the entanglement purification part has been thought to be the more difficult one, as it requires the so-called CNOT gate, which is really difficult to implement for qubits carried by photons. And exactly this part has (at least in theory) been solved by the Zeilinger-group.

What does this mean? Well, it means that quantum communication scaleable to large distances (with ploynomial overhead) might become available in the not-so-far future. At least one of the obstacles on the way to this goal semms to have vanished.