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Comment Re:String Theory Predicts Something? (Score 1) 348

by Yusaku Godai (#28225315) Attached to: String Theory Predicts Behavior of Superfluids

Right--there's no problem with taking a mathematical model and tweaking the parameters until it fits experimental results.

But when you do that, it means your model is dependent on some basic assumptions. In the case of string theories, a well-known parameter is the number of spacial dimensions. If a model happens to fit experimental evidence very well, but only if there are 11 spacial dimensions, that's all well and good. But that model is useless if the assumptions are false.

We might still be able to design experiments to discover whether extra dimensions exist. Right now they're not feasible, due to the amount of energy it would take to explore those depths. But it may be possible. Of there turn out to be enough extra dimensions to fit a string theory, then we can put a check next to that parameter saying that it's consistent with reality. And that's a mark in favor of the theory.
Security

Submission + - RSA Factoring Challenge is no more!

Submitted by
iplayfast
iplayfast writes: "RSA Factoring Challenge is no more. http://www.rsa.com/rsalabs/node.asp?id=2092
From the site Why is the RSA Factoring Challenge no longer active?

Various cryptographic challenges — including the RSA Factoring Challenge — served in the early days of commercial cryptography to measure the state of progress in practical cryptanalysis and reward researchers for the new knowledge they have brought to the community. Now that the industry has a considerably more advanced understanding of the cryptanalytic strength of common symmetric-key and public-key algorithms, these challenges are no longer active. The records, however, are presented here for reference by interested cryptographers.

I think they've realized that with cheap cpu's and modern OS's, these challenges are more at risk, and can be cracked more easily. They just don't want to pay the money :)"
Power

Submission + - Hybrid Cars No Better than 'Predicting' Cars

Submitted by
eldavojohn
eldavojohn writes: "There's no doubt been a lot of analysis done recently on energy consumption, especially on the road. Now, a study released today reveals that cars with traffic flow sensors built into them can perform just as efficiently as hybrids. The concept of an 'intelligent' car that communicates with the highway or other cars is an old idea but the idea of them using sensors to anticipate braking could vastly reduce fossil fuel consumption. From the article, "Under the US and European cycles, hybrid-matching fuel economy was reached with a look-ahead predictability of less than 60 seconds. If the predictability was boosted to 180 seconds, the newly-intelligent car was 33 percent more fuel-efficient than when it was unconverted." Now, the real question will be whether or not you can convince consumers that the three minutes of coasting up to a red light or halted traffic is worth the 33 percent less gas and replacing your brake pads/cylinders less often."

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