## True Random Number Generator Goes Online 439 439

amigoro writes

*"A 'true' random number generator that relies on the unpredictable quantum process of photon emission has gone online providing academic and scientific community access to true random numbers free of charge."*
## random.org ? (Score:5, Informative)

## Don't misunderstand (Score:5, Informative)

## quantum random number generators (Score:5, Informative)

## Other sources of true random numbers (Score:5, Informative)

Lava lamps [lavarnd.org]

Radioactive decay [fourmilab.ch]

Entropy [hd.org]

## Re:random.org ? (Score:5, Informative)

RANDOM.ORG offers true random numbers to anyone on the Internet. The randomness comes from atmospheric noise, which for many purposes is better than the pseudo-random number algorithms typically used in computer programs.The service has been operating since1998and was built and is being maintained by Mads Haahr who is a Lecturer in the School of Computer Science and Statistics at Trinity College, Dublin in Ireland.## Re:Wow! (Score:5, Informative)

Not really the hardest of encryptions to crack.

to solve a math problem like:

derivative of (5*sin 3x +6cos(-pi/2))

Nice!

Here is a direct link to the generator, you can

download the client from here as well:

http://random.irb.hr/ [random.irb.hr]

QRand Command-line Utility [v0.2, 2007-07-17]

Note 1: Compiles under Visual Studio and g++.

Note 2: Windows executable included.

Note 3: GNU Linux executable included.

## Re:already discovered (Score:2, Informative)

- RG>

## Re:Wow! (Score:4, Informative)

My mother doesn't even know what a sine is, let alone solve that to 15*cos(3x)

## Why pseudo-random for research? Reproducibility! (Score:3, Informative)

For scientific research, there's a very good reason to use pseudo-random numbers: reproducibility.

If you're analyzing a stochastic model, you want to be able to generate lots of runs with different random sequences and gather statistics from the ensemble. But if you see interesting behavior in a particular run and want to take a closer look, you want to be able to go back and run it again, exactly as it happened the first time. In this case, you don't want real randomness, you want pseudo-randomness with good statistical properties. I'm currently checking through my code to make sure you can do just that when using this tool [edbaskerville.com].

## Re:lava lamps at SGI (Score:5, Informative)

That would be Lavarand [wikipedia.org] from, oh, just 10 years ago [archive.org].

Rich

## Re:random.org ? (Score:5, Informative)

## MPAA is on to you! (Score:3, Informative)

## Re:random.org ? (Score:5, Informative)

I wonder, how could you know that their numbers are truly random, as they claim?You can never know that. You can test "properties of randomness" and conclude "it looks random." But you have no way of knowing if that hopefully random sequence cross-correlates to a non-random sequence you haven't found, but that passes all of the tests.

On the other hand, there is no randomness like quantum randomness. So if you believe their bit-stream faithfully represents the source, then in this case you can feel pretty good about it.

## Re:Don't misunderstand (Score:3, Informative)

In most cases it would, depending on the random distribution you're getting. Eg, in a random 8-bit number, you have 0-255. 111 of those start with 1, which is 43%; 67 start with 2, which is 26%; 11 each start with 3 through 9, which is 4% each.

## Re:Other sources of true random numbers (Score:3, Informative)

## Re:wonky definition of pseudo-random (Score:3, Informative)

[B.v.L]

## Re:Wait... (Score:3, Informative)

> for it to generate the number 42 a thousand times in a row...

> Not so.

> A random number generator might generate numbers in the range 0x10000000 to

> 0xfffffff0 (and thus never generate 42 (0x0000002a) as a result). As long as

> the distribution within that range is uniform, non-periodic, and lacking in

> underlying structure, it's random. If it meets the first and last requirement

> but is periodic, then it's pseudo-random.

Actually so!

Your range theory is a misunderstanding of RNG (true or pseudo). To restrict the range of values output is simply a matter of interpreting the bitsream in whatever way you choose.

I could take any bitstream and get numbers either integer 1 and integer 2, and no other values allowed, but that doesn't mean the RNG is limited. Thats just my algorithm stripping all but the last bit and adding one, or whatever way I choose to restrict the range of numbers. That process has nothing to do with the underlying RNG and its randomness.

## Re:wonky definition of pseudo-random (Score:3, Informative)

So long as your selection method for the bytes was sufficiently arbitraryAs long as it was fairly random, one might say...

You see the problem?

## Random numbers and human psychology (Score:3, Informative)

Because then your own psychology comes into play.

If you ask people to pick a number between 1 and 10, the vast majority of them won't pick 1 or 10. People just don't like the edges. I think that they avoid 5, too, because it's right smack in the middle. For a number between 1 and 10 to be random, most people subconsciously want to make it not stand out and will pick something like 3, 6, or 8, thus not making it even random enough for gaming.

Also, in the same vein of not standing out, if you ask people to pick multiple numbers between 1 and 10, most won't allow there to be any patterns in them in the attempt to make them more random, thus actually making them less random. For example, if you ask people to pick five numbers, most won't pick something like 4, 4, 4, 4, and 4, even though it's a legitimate combination that's just as likely as something like 7, 3, 1, 1, 9.

Another example. When I was in high school, I used to play $5 in the lottery once a week, figuring that it sure would be convenient if I never had to bother going to college and get a job and so on. I usually just selected the quick pick and let the machine pick my numbers. Once, though, I manually picked 1, 2, 3, 4, 5, and 6 for the first ticket, 7, 8, 9, 10, 11, 12 for the second, and so on. My dad basically said, "You're an idiot. Those numbers will

nevercome up, and you just wasted five dollars!" He never quite got it that, aside from the lottery being a colossal waste of money to begin with, it didn't matter what numbers I picked; any given set was just as likely to come up as any other given set. Not having six consecutive numbers is merely imposing human psychology on the random numbers, which could have very well been consecutive numbers.If I'm not mistaken, several years ago, someone proved that the digits of pi are random. That if you expand it out to a bazillion decimal places, you'll eventually run across patterns like 0123456789 and such. As humans, with brains that are designed to seek out patterns, it strikes us as interesting, perhaps even as some sort of sign that the numbers aren't random. Nothing is further from the truth, though; the

lackof such patterns would be a sure sign that the numbers aren't random.