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Comment: Re:what? (Score 2) 54

by HiThere (#49764293) Attached to: Universe's Dark Ages May Not Be Invisible After All

Higher energy photons are distinct from lower energy photons in having a shorter wavelength. They both travel at (about) the same speed. Presumably in a true vacum they would travel at exactly the same speed.

Thus blue light is more energetic than red light, and has a shorter wave length. You measure the energy of the photons by absorbing a certain number and measuring the change in velocity or temperature of the thing that absorbed them. (Usually this is done by some sort of photocell arrangement were the absorbtion translates into electron volts, and that's what you actually measure. I believe that this has been done down to the single photon level, but I'm not sure.)

Comment: Re:Sudden? (Score 1) 267

by HiThere (#49759627) Attached to: ESA Satellite Shows Sudden Ice Loss In Southern Antarctic Peninsula

Money is not equivalent to free speech, no matter how you twist things. I do not accept your arguments.

It is worth noting that one of the arguments which I read to be against the "free press" is the statement "The power of the press belongs to the man who owns one.". I don't fee this is sufficient grounds to be against freedom of the press, but it certainly highlights the limitations on its desirability. It's a way that only empowers the wealthy, as opposed to free speech which is available to the eloquent, whether rich or poor. And that highlights a limitation on the desirability of free speech. But the constitution made the best of things, but requiring *both* free speech and the free press. It would be reasonable to equate money with the free press, but not with free speech.

Comment: Re:Do people really take this risk seriously? (Score 3, Interesting) 230

by HiThere (#49753819) Attached to: Asteroid Risk Greatly Overestimated By Almost Everyone

A large impact in a shallow ocean area might well in every human dying within a decade. Most immediately. It would also first steam clean the planet, and then set an ice age in motion.

Now I'll grant that this is unlikely in any century, less likely by far, in fact, than that we'll do the same thing to ourselves via war or some other means. (War seems the most likely, but it's not the only contender. An escape from a biological warfare lab is a possibility. I'm not counting natural evolution as "doing it to ourselves", but it's happened to other species. In fact it is currently happening to a large number of amphibian species, some of which have already gone extinct.)

But I do consider asteroid impacts worth worrying about. Not worth obsessing about, however, as they are a bit down the ladder when it comes to humanity exterminators.

I also question his method of assigning proper degree of concern. And the reliability of his assertions. E.g. he claims that only one person has ever been hit by a meteor, but there's no evidence that that's true. He should have said only one person is known to have been hit by a meteor. But how many people in remote areas of the planet could have been hit and the reason for death, or even the fact of death, not officially acknowledged? And clearly nobody could cite an instance before around 1700, as even the existence of meteors was denied. So you need to ask what is the probability of someone being hit by a meteor and the fact being officially recognized. This is a quite different question. He performs the same type of factual manipulation (less obviously) in a few other places.

That said, it's not a major concern while other concerns rate higher. But a species ending event is worthy of particular concern over and above the concern over the individual lives lost, as you also need to consider the future lost, and not just a few personal futures, but all human futures.

Comment: Re:Root cause = speed over security (Score 1) 71

by HiThere (#49738759) Attached to: 'Logjam' Vulnerability Threatens Encrypted Connections

OTOH, using "roll your own crypto" is nortorious for individualized holes and weaknesses. It does tend to mean that the "one size fits all" means of breaking the code won't work, however. Or at least may well not work.

That said, if you have good enough communication to share custom crypto programs, you may be better off using a one-time that can't even theoretically be broken. But it does require a good source of random numbers (e.g. amplified triode vacum tube with no input so you're just amplifying noise). Such things are reasonably easy to build, but for some reason they aren't normal computer accessories. (Video cams watching a flickering flame are another good source.)

But custom crypto is hard to do correctly. AND it requires good communications to standardize the programs. So if you have the communication, a one time pad is better.

Comment: I am not able to find that disproof (Score 5, Insightful) 263

by HiThere (#49721239) Attached to: Book Review: The Terrorists of Iraq

The assertion that the infinite monkeys theorum has been disproved seems incorrect. Searches for the named scientist in conjuction with monkey also fail.

IOW, I suspect the entire article is garbage. I will admit that this is based on the fact the the only easily checkable statement appears to be factually incorrect, but if it's wrong where you can check, what should you believe about the places where you can't check?

Comment: Re:As long as the jobs actually go to the kids (Score 1) 249

There's also absolutely no guarantee that anybody will be hiring those skills. Why should the rich bastards be the only ones who demand guarantees?

Were I advising someone in school, I'd look at the current economics of STEM professions, and the BS surrounding them, and advise the students to study foreign languages. Or *something* besides STEM. Otherwise in 20 years you'll have a huge debt and no way to ever pay it off.

Comment: Re:It formed during the Holocene? (Score 2) 293

by HiThere (#49706927) Attached to: Larson B Ice Shelf In Antarctica To Disintegrate Within 5 Years

Sorry, I can give general explanations about how ice shelves work, but I don't know the specifics of Larson B. But clearly different sea levels would mean that the ice shelves would form in different places. As to what name they would have ...

As an aside a lot of the argument among paleontologists, and others of the ilk, is about names rather than about facts. E.g. there often isn't enough solid information available to say whether two fossils are of different people guess. Some people like to split spieces on small basis, others like to clump, and there often isn't a good reason to decide between the two. Similarly, what difference in locations would justify giving an ice shelf at two different times, and slightly different location, a different name? The ice wouldn't be the same, because the ice on an ice shelf is continually, if usually slowly, moving out to sea. But people like to draw boundaries.

Work expands to fill the time available. -- Cyril Northcote Parkinson, "The Economist", 1955