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Using Lasers To Generate Random Numbers Faster
Pranav writes "Using semiconductor lasers, scientists from Takushoku University, Saitama University, and NTT Corporation achieved random number rates of up to 1.7 gigabits per second, which is about 10 times higher than the second-best rate, produced using a physical phenomenon. Future work may center on devising laser schemes that can achieving rates as high as 10 Gbps."
The "Real Genius" and "sharks" jokes you're about to post are less than 1% as funny and clever as you think they are. And no, you're not making them ironically, you're making them because you really do think they're good jokes. This is because you are retarded.
Has anyone out there actually had their system bottlenecked by lack of random numbers? I had thought that the bottleneck in serving large amounts of SSL content was processing the asymmetric part of the cyrpto -- hence the need for SSL accelerator cards. It's a nice invention and a creative application of physical process, but I really want to see just one case where this would be lead to a substantial benefit.
As an aside, computer simulations always use pseudoRNGs like the Mersenne Twister[1]. For a reasonable exponent (I use 19937 in my simulations), this results in a period > 10^6000 and virtually no correlations between adjacent calls. The notion of a computational physicist using a real physical RNG is laughable.
[1] http://en.wikipedia.org/wiki/Mersenne_twister
"The generation of random numbers is too important to be left to chance." -- Robert R. Coveyou
They should somehow tap into phpBB. I'm already on some forums that generate more than twice this much bullshit every second :)
"Fields and applications that could benefit from their work are numerous, including computational models to solve problems in nuclear medicine, computer graphic design, and finance."
This explains a great deal.
"I bless every day that I continue to live, for every day is pure profit."
If it is chaotic and you believe in the Everett Interpretation, they've just produced the worlds fastest world splitter.
Next, the article claims...
Generating random numbers using physical sources -- which can be as simple as coin-flipping and tossing dice -- are preferred over other methods, such as computer generation, because they yield nearly ideal random numbers: those that are unpredictable, unreproducible, and statistically unbiased.
This is garbage -- there are applications where people prefer physical sources, but those of us doing simulation work realized long ago that good algorithmic sources are far better for our needs: 1) It's mighty hard to debug a complex simulation model without reproducibility; 2) You can use the reproducibility to induce covariance between runs, greatly reducing the standard error of your estimates for a given sampling effort; 3) The distributions of algorithmically generated pseudo-random numbers are provably uniform, whereas for physical sources the best you know is that they haven't (yet) failed a hypothesis test for uniformity. Finally, the last statement about being "statistically unbiased" is utter nonsense -- unbiasedness is a property of an estimator, not a distribution.
I suspect encountering the words "random" and "laser" in the same sentence would be rather disconcerting to an eye surgeon. Maybe I'm off topic...
We really, really need more hardware random number generators (RNG's) within CPU's. I think this is one of the more important things for Intel and AMD to work on (VIA and Intel have already working hardware RNG's for x86 as far as I know, with Intel though it is only for an embedded processor).
Otherwise we will have to rely on "commodity" hardware to generate enough randomness to seed our pseudo-RNG's. And since a keyboard, harddisk and video cannot be trusted to be in a machine, and since using the NIC has too big a tie with the outside world, we are quickly running out of entropy sources. So a hardware RNG is definitely a very good idea.
That does not mean that these guys have struck gold. There are already fine RNG's available for use within CPU's. I don't know how secure their device is (what happens when it is underpowered/cooled etc) but speed is not really a problem right now. Of course, if it is easy to implement in current designs: why not?
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No one will need more than 637 kb of random number generation for a personal computer.
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this can be treated as a "classical physics" problem (and I have every reason to believe his statement about QM length re: a roulette ball), then at least theoretically the statement is correct.
But theory and practice are often vastly different. In a case like this, the information necessary to account for all the relevant initial conditions, and the calculations necessary to go from there to final result, are so vast as to make it ludicrous to even consider trying such a feat. Further, we don't even have the expertise to make such calculations even if we had such "perfect" information.
Think about it: even with classic physics, this is an awesome candidate for the "butterfly effect", in which miniscule differences in initial conditions could cause highly significant differences in the outcome.
See, you don't just need to know the mass of the ball, and its velocity, and such. You would have to know the exact size and mass of the bearings, and exactly how much lubricant had been applied. You would have to know the exact size and shape of the little fences between the numbers on the wheel (air resistance), and calculate Reynolds numbers for them. You would have to know how many people are around the wheel (if any) and how they are breathing. Is someone wearing perfume? Will that affect someone else's breathing? Even without people, did someone add a little bit extra glue at this particular spot, during the manufacturing process?
And so on.
It simply would not be a practical excercise. Even in controlled conditions, and without confounding factors, two well-lubed roulette wheels are almost certain to give you significantly different results, no matter how you try.
Theory is great, but reality trumps.