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More Random Randomness

Posted by timothy on from the pudding-is-like-yogurt dept.

jfleck writes "According to the American Institute of Physics' Physics News Update, Kent State physicist James Gleeson has developed a technique for generating numbers approaching true randomness. His trick is to shine light through a liquid crystal, taking advantage of its turbulence and avoiding the inevitable risk of predictability in deterministic random number number algorithms."

5 of 80 comments (clear)

  1. Re:silly by GMontag451 · · Score: 3, Informative
    There are two different meanings of the phrase "random number". One is the coin-flipping variety, where any number within the range is possible, but is only as likely as every other number in the range. AFAICT, this isn't the kind of random numbers the article is talking about.

    The other kind of random number is a number that is entirely entropy. In other words, an uncompressible number. This type of number is extremely hard to generate, and by definition, cannot be generated by an algorithm shorter than the number because this would be a form of compression.

  2. Re:Isn't this kind of a "no duh" by lommer · · Score: 2, Informative

    the only problem is that most of your variables won't change in matters of seconds, so theoretically the same number would come up a lot of times in a very short period of time.

    If you use a LOT of variables you approach a good version of randomness, but if someone knows the input data to your system (e.g. by taking separate measurements for themselves) and your algorithim, they can predict your number with 100% accuracy, which is bad in the crypto-security world.

  3. Re:silly by GMontag451 · · Score: 3, Informative
    If your random number generator is incapable of generating a string of 256 0's in a row, there is something wrong with it.

    That is true for the first kind of random number generator that I talked about, not for the second kind.

    Maybe I can describe what I'm talking about better. There are two different types of random number generators. One kind is a generator that randomly produces numbers, which is what you are talking about. The other kind produces *random numbers*, which is something completely different. It is the difference between the generator being random, or the number itself being random no matter how it is generated.

    Randomly produced numbers are equidistributed along the range of the generator, usually from 0 to 1. Random numbers are numbers that are impossible to compress. A number is random no matter what the next result is, but is only randomly produced with respect to the numbers produced before and after it with the same algorithm.

  4. Another source of randomness by jeff4747 · · Score: 2, Informative

    Random.org

    They generate random numbers based on hardware, using the decay of radioactive elements.

    Yeah, still hardware, but you're never going to get truly random in software. Something has to put in a bit of chaos into the system that you just don't get in a computer. Otherwise they'd just crash all the time.....wait a minute! Windows must have some super-secret random number technology!

  5. Intel True Random Number Geneator by hthalljr · · Score: 2, Informative

    You probably have a TRNG right on your desktop. Intel has incorporated a true hardware random number generator (TRNG) in Pentium III and Celeron chips. It's based on the quantum-mechanically random Johnson noise across an undriven resistor. Two resistors are used to eliminate any external effects. Here's a good explanation from Cryptography Research, Inc.: ftp://download.intel.com/design/security/rng/CRIwp .pdf Here's Intel's TRNG page: http://www.intel.com/design/security/rng/rnghow.ht m RSA believes in it: ftp://download.intel.com/design/security/rng/RSA_B SAFE.pdf