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Odd Lots


  1. Alex Dillard says:

    “It’s true that anything can be cracked.” That’s not completely true, one-time pad can’t be cracked.

    1. Bob Fegert says:

      That’s exactly what I was going to say 🙂

      One-Time-Pad is an XOR with a true random key of equal length to the file being encrypted. This cannot be decrypted by any method..a quantum computer would have no more chance than an old Apple 2.

      1. Well, sure. I read Bruce Schneier too. The issue isn’t cracking a one-time pad. The issue is using it. When your key is the same size as your data, and when you have hundreds of megabytes of data, things start to get…clumsy. It’s technically possible to use one-time pads in cloud work, but let’s just say I don’t expect to see it happen on a commercial (as opposed to purely experimental) basis.

  2. Rich Rostrom says:

    That Economist story is not about American science. Most of the problem journals and scientists are not American. China and India are rife with garbage “papers” and “journals”.

    A bigger issue to me is the lack of verification. Any security system which is not regularly challenged is weak.

    The lead societies in the sciences should have “tiger team” groups that fabricate bogus papers for submission to journals – and any journal that passes one gets sanctioned. Keep ’em on their toes.

    Also, ISTM that expecting all scientists to do original work may be too much. What might be better all around is to have all submitted papers repeated. Repeating and verifying others’ work is of course less gratifying, but it’s still useful and necessary: a valid career.

    (That still leaves the question of how the costs of duplicated work would be paid for.)

    In the end, a lot less work would be published, but the quality would be much improved, and genuinely bogus work would be eliminated.

  3. Tom R. says:

    Rocket engines. The link to the piece on the N1 Soviet rocket made me think back to some things from my distant past.

    Back in the 1960’s the big problem with designing a liquid fueled rocket engine was the injector design, which was almost totally empirical. That is engineering speak for saying trial and error.

    I have no evidence that this is true, but the article made me think that there may be a more fundamental reason why the Soviets went with lots of little engines and the US built the huge F1 engines.

    Although there was no way to design an injector place from first principles at the time (or even now I believe) the US at that time probably had computers powerful enough to at least simulate how well various designs might function while the soviets did not. The bigger the engine the more critical the injector design becomes since a bad injector can lead to combustion instability which can at best also produce major thrust variation and pogo and at worst can just cause the engine to explode.

    This is all speculation on my part, but having started as an engineering major in aerospace engineering in 1965 and latter changing majors to Systems Engineering in order to be able to play with the new PDP-8 hands on I do wonder about this. Perhaps someone else has more direct knowledge.

  4. Jim Tubman says:

    Very interesting story about the Russian moon rocket; thanks for sharing it.

    But as a fan of the American space program since before I could read, I can’t help but despair that at the present time, Russia is the only country that can still reliably send people into space.

    1. Carrington Dixon says:

      Perhaps we should just be thankful that there is still one country that can reliably send people into space.

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