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Quantum Programming with Perl
moyix writes: "There's an article over at perl.com that describes how to use a perl module called Quantum::Entanglement. Using this module, one can simulate programming for a quantum computer. Developers looking to keep their skills current well into the next decade should check this out ;) Debian folks can grab libquantum-entanglement-perl and libquantum-superpositions-perl."
I always wondered how Larry Wall was seemingly in 10 different newsgroups at one time. I guess he's been using quantum physics all along...
"No fair! You changed the outcome by measuring it!" -- Professor Farnsworth from Futurama.
I suffer from attention surplus disorder.
And to think people complained that garbage collection was inefficient! Actually, though, this is a huge step forward for Perl. Now, with just a few lines of code, you should be able to consume massive numbers of CPU cycles while still actually accomplishing something.
The module actually looks pretty cool. It says that some simplifying assumptions were made. Does anyone know if the simulation is reasonably accurate? That is, could you actually set up a quantum computer to behave exactly as the simulated one?
I just happened to notice that Perl is being used for so many innovative research fields.
First of all Perl seems to be an excellent language for Bioinformatics, and Dr. Lincoln Stein is a leading voice in this area. Recently O'Reilly has been giving great coverage in this area.
Nanotechnology seems to be another area where Perl is getting much attention.
I believe the platform and vendor independence, absolute openness, and superb data munging capabilities of it are the main reasons for Perl's adoption in such academic research.
But, although I am an aspiring Perl advocate) and big Larry Wall fan myself, I wonder just how optimized these modules are for such intense low level work....
Broken Hearts are for Assholes. - Frank Zappa
First off, I thought just about everything was workable in PERL but this is scary. :) Regardless, to the best of my knowledge there are no working quantum computers (tangible at least.) How can we be sure that code created with this will truely work the same way when it's eventually put onto an actual quantum computer? Even were this based on a tangible prototype I'd feel there'd still be cahnges that'd need to be made. *shrugs* Guess I'm just a jerk about toying with theory. :)
( o ) one could say I'm rather baked
Anyone interested in doing any type of quantum computing should check out Dr. Damian Conway's excellent Quantum::Superpositions. It is an extension to the perl language which adds the operators "any" and "all"... it's lets you do *incredible* things like:
... }
... }
use Quantum::Superpositions;
if ($x == any($a, $b, $c)) {
while ($nextval < all(@thresholds)) {
$max = any(@value) < all(@values);
A good place to go and discuss the in's and out's of the cooler aspects of the perl community is perlmonks.org, check it out some time...
For some of us, this is nothing new.
Quantum Perl - "No longer will there be more than one way to do something, but rather there are an infinite number of ways to do everything!"
"Everything you know is wrong. (And stupid.)"
Moderation Totals: Wrong=2, Stupid=3, Total=5.
I know the module is supposed to simulate programming a quantum computer, but it is not trying to simulate a quantum computer, there is a fundamental difference.
Also, I sincerely doubt that quantum computers will function this way, it is not the purpose of quantum computers to store multiple values for a single variable; it is to use physical resources more effectively
nihilist, in making this post; you didn't take into account the _very_ quantum principle of uncertainty ;). It could be real, it could be a hoax.
April 21-27-- Slashdot Blackout: Do your duty.
After Microsoft's incredible implementation of the recursive crash (anyone remember the crash recovery that crashed?), this module now gives them a chance to have the superpositioned crash: your computer is both crashing and still alive.
--- Sigmentation Fault - Comments Dumped
It's 2:30 am and I'm thinking how exciting quantum computing is. :(
Awwww... I need a life...
At least I might or might not have a life.
use Quantum; my $jump = Quantum::Leap->new(); # nothing happens... Damn! Why doesn't it work??
"This still leaves us with plenty of ways to make Perl behave in a thoroughly unpredictable fashion."
Is it just me, or doesn't "good Perl code" already work that way unless you've spent the past 10 years developing for it? I for one can't make heads or tails of tight Perl coding methods.
Do you like Japanese imports?
And when one of these application crashes, itll go with a bang allright.... *Access Violation* there goes the space-time continuim..
----- Whats wrong with this picture? http://www.revoh.org:1234/whatswrong
In any case, some researchers at IBM and other places have built small quantum cells than can make use of the above algorithms.
The problem with quantum computing is that many answers are revealed at once, most of which are incorrect. The algorithms need to be able to separate the wrong from the right. It's a task for bright logicians :)
-
I'm sure you can run Grover's algorithm in *simulated* O(sqrt(n)) time...
Did I mention that simulating a quantum system on a deterministic machine will require EXPONENTIAL time and space?
Go Perl.
Also, remember that this does not turn your box into a quantum computer. It's well known already that quantum computers cannot do anything that normal computers can't (they both are Turing machines); they just do some things quite a bit faster.
Escher was the first MC and Giger invented the HR department.
http://www.internetnews.com/dev-news/article/0,,10 _943731,00.html
Scientists at IBM Corp.'s (NASDAQ:IBM) San Jose, Calif.-based Almaden Research Center this week rushed to report that they have performed a challenging quantum computer calculation, causing a billion-billion custom-designed molecules in a test tube to become a seven-qubit quantum computer.
With that breakthrough, they solved a simple version of the mathematical problem that is the crux of many of today's data-security cryptographic systems. According to Nabil Amer, manager and strategist of IBM Research's physics of information group, this was quite a feat.
"This result reinforces the growing realization that quantum computers may someday be able to solve problems that are so complex that even the most powerful supercomputers working for millions of years can't calculate the answers," said Amer.
Broken Hearts are for Assholes. - Frank Zappa
There's a C++ version of the library here.
Just thought you'd want to know
Finally, an application which Perl can't make more confusing.
-Paul Komarek
Although I can't get to the article right now, I do know a little about quantum computing thanks to having just finished a thesis on the subject.
Studying the actual research in the field reveals that a real quantum device does not at all resemble a superintelligent "infinitely-faster-than-my-Pentium-4" computer of the future. To understand the difference requires understanding the fundamental nature of a quantum device and how it differs from a digital device.
The atomic unit of a quantum computer is a physical system of some sort that exhibits quantum behavior, such as a single electron and its spin. Whatever the implementation, the unit is called a qubit. A single qubit contains information sometimes described as a vector of complex numbers.
A digital computer, of course, operates on bits which allow only two states, the most common implementation of which is a high or low voltage at some defined point in an electrical circuit.
Some operations are natural and easy to perform on bits; these are AND, OR, NOT, XOR, and their Boolean friends. These operations, in turn, lend themselves to an easy and natural implementation of integer math. Other operations do not have a natural representation in digital computers, such as real-number arithmetic. For the relatively few occasions that call for irrational numbers, we make do with approximations and call it "floating-point" math.
The qubit's advantage is that, thanks to quantum mechanics, some operations which are very difficult for a digital computer are easy and natural for qubits. Notably, a set of qubits can perform a Fourier transformation in near constant time--an astounding operation that is so far believed to be impossible on any kind of Turing machine.
The other side of the coin, which is rarely understood by mainstream news reporters, is that the qubit is completely unable to address most of the rest of our favorite operations, such as integer addition. To ask a qubit to count from 0 to 9 is extremely difficult, maybe physically impossible.
If that weren't bad enough, quantum algorithms have to deal with other constraints such as the prohibition against creating a copy of an unknown quantum state. Therefore, your quantum Perl is going to have to start by doing away with the assignment operator. Qubits also have a nasty tendency to occasionally do things completely unexpected and unpredictable; this requires massively redundant calculations to reduce the probability of error to something acceptably small. (Of course digital computers suffer from random bit rot as well; it is solved with similar error detection and correction algorithms.)
All these obstacles discouraged any serious interest in quantum devices for some time. However, recently (1997?) Peter Shor published the first important quantum algorithm, which factors large composite numbers in polynomial time. In case you don't know, a computer with such a capability would have staggering implications. Much of the world's data protection is based on the RSA algorithm which relies on the difficulty of factoring large numbers.
Hence, the last few years have seen no shortage of funding or interest in quantum computing. Unfortunately, the mainstream media has caught just enough of the conversation to get the false idea that quantum computers are going to blow away all of the digital technology in existence, coming soon to a Best Buy near you.
Anyway, the moral of the story is, don't start saving for that Pentium-Q just yet; not only is a quantum device completely inappropriate for the overwhelming majority of computing tasks, but the current state of the art is a machine on the order of 10 qubits or so. (A few hundred qubits will be needed before Shor's algorithm presents a threat to current encryption.)
More realistically, you might expect to see one day in your lifetime a "quantum processing unit" that exists as a special-purpose extension to your digital processor--think along the lines of the 80287 floating point coprocessor. Even this kind of application is decades away at best.
But I have myself used a simple NMR quantum computer to execute Grover's search algorithm on a very small (4 element) search space when I was working at MIT. So there.
I wonder... Who out of anybody would be the first group to adapt and use this...
SendSpamTo(any($a, $b, $c, {....})...
Wow... Quantum Spam... Imagine the possibilities of bandwidth usage...
Or How about...
DOSAttack(any($a, $b, $c, {....})...
A Quantum DOS attack...
Hey just thinking out load how slow the net could be in the future
schrodingers cat paradox in perl
The real use of this is for people who want to experiment with quantum _algorithms_ on small data sets and learn and understand better how quantum computers work and how quantum calculations are put together. Writing quantum algorithms is hard and confusing to somebody familiar with classical computation, even if you are familiar with quantum mechanics. There are very few useful quantum algorithms (Gover's search and Shor's factorization algorithms are the two most famous and interesting IMHO). This module might encourage more people to come up with and experiment with quantum algorithms that take advantage of the "inherently parallel" nature of quantum computing.
Note that though I am no expert, I did actually write something modestly similar to this Perl - an interpreter that read a series of meta-language commands and turned them into physical magnet pulses for spin flipping on an NMR quantum computer we had at MIT. We never bothered to write a simulator for it, but now that I think about it, it would be cool to have this. Kudos to these guys for doing this.
Now if somebody could just make a quantum computer with, say, 20 or 30 qubits I might be convinced that quantum computing could eventually do useful calculations and that the decoherence problems and setup problems for a large number of weakly coupled qubit units are not intractable. Perhaps an alternative to NMR as the substrate for quantum computing might get farther.
Try to learn at least one of the theories of quantum mechanics before you start throwing around principles, okay?
For one thing, QCs do exist - in fact, they demonstrated Peter Shor's 1994 factoring algorithm on a recently built 7-qubit box, factoring 15 into 3 and 7. You may say big deal, but it can factor ANY such integer in polynomial time. Usually the NSA is about 10 years ahead of the private sector, so I figure they've got at least 10 qubits by now. You should be worried - most public-key encryption methods rely on the intractibility of factoring.
Secondly, the Heisenberg uncertainty principle only states that you can't predict with 100% accuracy which eigenstate a qubit will collapse into upon measurement. You can, however, compute a probability amplitude (which ends up being a complex number) that it'll be a 0 and another probability that it will be a 1. And it is possible to perform operations upon one or more qubits without measuring it - the idea of creating an operation that doesn't collapse the state is the crux of Quantum Computing.
Unlike macroscopic physics, we don't know WHY things work on the quantum level the way they do. We've gotten relatively decent at predicting the end results though. So, we're just as confused as before... but we're capable of doing useful stuff with it. Don't knock it.
Incoming message for Mr. Shor: Your algorithm doesn't work.
(ob. H2G2 ref.) Wait a minute ... *slaps forehead* Now I understand! 42! It all makes perfect sense now!
Between the voodoo and uncertainty of quantum mechanics and \%{$Magical{'Perl'}[$#$syntax]}, who'll ever need to encrypt their code? =)
Let's say you have two qubits representing all superimposed numbers between 0 and 3 and you want to add 1 to all of them simultaneously. According to quantum computing experts, one can perform an operation on all the numbers at once. So after the addition operation the two qubits now have all the results between 1 and 3 (assuming the carry is thrown away). The question is, how does one get just one of the results back and be certain that it is the correct one?
Another way to play around with nonclassical algorithms and get your feet wet with quantum programming would be QCL.
QCL is a procedural quantum programming language which provides nonclassical language elements such as unitary operators, running code in reverse, scratch space management, etc. A Linux interpreter (GPL) which simulates a quantum computer with an arbitrary number of qubits is available here.
For one thing, QCs do exist - in fact, they demonstrated Peter Shor's 1994 factoring algorithm on a recently built 7-qubit box, factoring 15 into 3 and 7.
I wouldn't get too exited about this. Shor's factoring algorithm is a probabilistic algorithm, and for a small number such as 15 you could replace the entire quantum part by rolling some dice and still manage to find factors. So it's possible that the demonstration you refer to messed up somewhere but still managed to factor 15.
Also, NMR quantum computing (which was used for that demonstration) is fundamentally limited to a maximum of around 12 qubits, and I seriously doubt the NSA has got anywhere near 10.
Secondly, the Heisenberg uncertainty principle only states that you can't predict with 100% accuracy which eigenstate a qubit will collapse into upon measurement
This is not the Uncertainty principle. This is the measurement postulate.
The Heisenberg uncertaintly principle says things like " if you know the position of a particle precisely then you can't know anything about it's momentum" etc. Or, to wax technical, the products of the "errors" for position and momentum being greater than half the expectation value of the commutator of the operators represneting position and momentum.
:wq
Damian Conway will give a public talk at ETH Zurich (Swiss Federal Institute of Technology) on Monday, February 11th, 2002 at 17:00h.Everybody is welcome. Location: Departement of Information Technology and Electrical engineering, Gloriastrasse 35; Auditorium E6. http://www.ee.ethz.ch/events/index.en.html Abstract
First of all, a qubit box does not classify as a computer. If I hooked up a couple logical gateways together that does not classify as a computer. A computer must have input, output, and be capable of being programmed in some way.
/. is that there are too many smart people on it. Can't get pissed off at anything without getting mod'd as a troll...
There is no fundamental theory of quantum computing. As mentioned in another response, there is no boolean algebra equivalent for quantum computing.
Computers are based in absolute truth. Quantum computing relies on probability. That is where my question of praticality comes in.
I do not doubt that the NSA is more technologically advanced but don't give them too much credit...
I get sick of people spouting about how quantum computing is so great because it doesn't even exist yet. This may sound ironic seeing how everyone responded to my post, but it pisses me off when people who have no understanding of quantum mechanics start saying, "Quantum computing means you can executed all your code all at the same time" and stuff like that.
The problem with
int func(int a);
func((b += 3, b));
the superpositioned crash: your computer is both crashing and still alive.
But you still have to look inside to b0xen before you know which state it's in, right?
Isn't that pretty much how it works anyway? What, with the fact that most websites seems so well tested.
*cough*
Please mod this post only if you think others should/n't read this. I have enough ego^H^H^Hkarma. Thanks!