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Comment Re:Vacuum tubes handle EMP's better (Score 1) 97

I see your anecdote and raise you another one: years ago, using an exploding wire disruptive switch in an LCR circuit (the C was 25 kV, 4 uF -- heavy but portable) and a really basic parabolic antenna, I permanently destroyed a portable CD player a few meters away.

Also, in military experiments, even diesel generators were disabled by EMP from a nuclear explosion when the stator windings shorted between turns. Your comment only applies to solid-state parts which are either 1) disconnected from wiring that has enough inductance, or 2) subjected to an insufficiently strong EMP. In two circuits with similar interconnect inductance, one using tubes and the other solid state devices, the tube one would be able to withstand an EMP several orders of magnitude stronger because a vacuum arc takes tens of kilovolts even in small tubes with heated filaments, whereas most solid state devices would be destroyed after a few volts.

Comment Re:Vacuum tubes handle EMP's better (Score 1) 97

If the wiring around the tubes had protection (say ultrafast spark gaps), the tubes would have come out unscathed, because even close-by electrodes in typical receiver tubes with the cathodes fully heated still need many tens of kV to cause a vacuum arc. A nuke-caused EMP can't directly cause that in a stand-alone tube unless you're in the blast radius -- the voltage was induced in the wiring. That means the damage to the tube comes from the wiring, not directly from the EMP, and so your comment is misleading.

Comment Re:Vacuum tubes handle EMP's better (Score 1) 97

The voltage spike was enough to cause internal arcs in operating tubes, vaporizing electrode material.

That they were operating is the first critical factor. Vacuum arcs between metallic elements that are not boosted by thermionic emission and are just driven by field emission require gradients on the order of gigavolts per meter, so even for small receiver tubes you'd need a difference of several million volts between the electrodes. With the cathode heated when the tube is operating, this is reduced by an order of magnitude. However, an EMP from a nuclear explosion that would generate something like this in an unconnected tube puts the equipment within the blast zone -- never mind worrying about the EMP. Thus, the second critical factor is the circuits the tubes were parts of, because induction into the wiring they were connected to is what it took to create a huge voltage differential between the electrodes -- which also tells you how to avoid the problem: ultrafast spark gaps, which, at least according to this paper can be as quick as picoseconds.

Comment Re:Microphone access. (Score 1) 223

Bullshit, I'm in my mid-30s and I can still hear 17 kHz, and I know others in my age range who have even better hearing. I'm pretty sure most of us who didn't spend their 20s in loud nightclubs or concerts (at least not without musicians' earplugs), or nowadays blasting headphones directly into our ears, still have good high frequency hearing for another couple of decades.

Comment Theyre not refugees! (Score 3, Interesting) 418

Most of these people are economic migrants, not refugees. In the case of Syrians now flooding into Europe, for example, most did not come directly from Syria — they came from migrant camps in Turkey. Turkey is a stable and safe country, but doesn't provide quite the level of social services and economic opportunities that a Western European country does. Of course, as has been pointed out in various places, the German government is worried about an aging population and needs young workers, so they opened the gates under the pretense of humanitarian reasons — preservation of culture, values, and social cohesion be damned.

Comment Re:Is mathematics invented or discovered? (Score 1) 189

The integers extended by some irrational, say sqrt(2), requires use of real numbers but does not involve uncountable infinities or infinite information.

Only if you're limiting the accepted irrational numbers to a countable subset of R. That's not very useful. For example, it was demonstrated in a paper a few years ago that if you could have infinite precision real weights for the connections of an artificial recurrent neural network, that would allow super-Turing processing. However, your restriction would break that and any other such approaches (and, of course, physics also breaks it -- such a thing cannot exist in the universe -- which was my point).

It is just applying logical rules on various abstract structures. There is no requirement that they be "real" in the sense of being the result of some measurement in the real world. That also doesn't require assumptions beyond basic deductive logic working.

You seem to have missed the point. I was saying that humans cannot solve non-computable problems in the general case. Mathematicians have the same theoretical limits as a digital computer. The "just applying logical rules on various abstract structures" is not solving non-computable problems (siome of the simplest examples of these are listed in http://mathoverflow.net/questi... ); it's an action that can be mapped to a computational process (and even in cases where said process cannot be effectively simplified beyond an ab initio molecular dynamics simulation of mathematicians' brains and their environs, it's still computational).

Comment Re:Is mathematics invented or discovered? (Score 1) 189

You should be asking this question of a physicist, not a mathematician — mathematical Platonism is just another religion.

Physics is clear on the question: there is a limit of entropy/information density in any finitly-bounded region of space. Initially this was demonstrated for flat spacetime in a result known as the Bekenstein bound, and was later extended to de Sitter spacetimes (and we're in an asymptotically de Sitter spacetime according to accepted cosmology). This means that physical quantities cannot be arbitrary precision (real-valued), because you can encode infinite information in a real number and that contravenes the aforementioned bound. Thus, real numbers are not real, and uncountable infinities do not exist in the physical universe. This severely limits the mathematics that actually applies to reality at a fundamental level.

Combining the above together with the fact that any causally connected system in the universe is finite in size (the limitations being accelerating expansion and the speed of light resulting in a cosmological horizon), any physical entity can be fully described by a non-deterministic linear bound automaton, which is a class of mechanistic information processing entities, even less powerful than Turing machines. That includes the human brain, and also the system comprised of the sum total of all human brains and any intelligent artifacts we ever create interacting together. The class of problems a non-deterministic LBA can solve is pretty limited. So how can mathematicians think and talk about concepts like uncountable infinities and everything in mathematics that depends on them, if their brains are based on physics in which these concepts play no part?

Let's separate the existence of thoughts on such concepts from the concepts themselves having any reality. The former are obviously connected to the physical universe via their neural correlates. As for the latter, they're easily explained as an extension of the sort of heuristics the brain uses in virtually all aspects of its functionality, as is well-known from cognitive psychology. As an example, concepts like the number pi (to a given number of digits) are just shorthands for their generative processes (to a given number of iterations or recursions). Even while mathematicians think about problems that are outside the class of those which are computable, their brains are not applying any magical non-computable processes to solve them. It's a combination of not really solving them (which would be impossible as they're not real) but processing them in other ways based on the assumption they're real, the luck and lack thereof of stochastic search that cognition oft relies on, and, without a doubt in some cases, accepting "solutions" which are wrong but unknowably so.

Comment Re:How is this different from the US GOP? (Score 1) 351

stupider then

Oh, the irony!

there's be

I believe the original quote from Oscar Gamble was “They don't think it be like it is, but it do.” https://en.wikipedia.org/wiki/Oscar_Gamble

then he gets credit for

The ride never ends!

it's ridiculously fucking stupid

You can say that again!

she is architect of much of the Obama policy Bibi haters

So she designed the Bibi haters of Obama policy?

nominee then Sanders

By now I'm pretty sure one of your keyboard, fingers, or brain hates you with a passion.

Comment Everyone one that has posted till now forgets (Score 1) 369

that there is yet another reason. The new lieberal Prime Minister Trudeau told Obama in his first phone call with him several days ago that Canada is pulling out of the US-led coalition against ISIS. I'm sure the libtards will claim that this had nothing whatsoever to do with Obama less than a week later canceling Keystone XL. Yeah, and my name is Donald Duck! Obama could have canceled this on many occasions before, especially while the previous Canadian administration was pestering him about getting approval.

While Canada's few aircraft in Syria were of little practical significance, this was a symbolic "fuck you" to the Americans and an indication that we Canadians are a shifty ally. Moreover, it shows the naive belief that if you leave ISIS alone, ISIS will leave you alone. The new PM has within a few short days of his term already managed to offend the US and show weakness to the terrorists.

One more thing worth mentioning is that, to the extent that one of the contributing reasons for blocking the pipeline was to decrease competition for oil exports (the KXL oil was designated for export after refining in the south, and the US also exports refined oil), that is against NAFTA rules. If such reasoning can be demonstrated, Trans-Canada has a case it can take to a NAFTA tribunal a maybe the WTO. Saying "but it's not in the best interests of America" makes the fallacy of looking at this one issue specifically, rather than the trading partnership as a whole — trading partnerships are in their essence quid pro quo, and you're obliged to do certain things that don't benefit you but help your partner, just as the partner is obliged to do so in return. If you don't like the terms, pull out of the agreement or renegotiate it rather than cheat and use bullshit excuses.

By the way, claiming environmental concerns is hypocrisy when the US has an order of magnitude more oil pipeline already, and California oil production is so much dirtier than the Alberta oil sands.

Comment Danger, Will Robinson! (Score 3, Insightful) 315

I'd like to caution the reader to take TFA with a grain of salt, lest they decide to use it as an excuse to feel better about getting less than the recommended 7.5-8 hours of sleep. Specifically, I'd like to note the following:
1. The study in question concerns the sleep requirements of people who have a lifestyle incomparable to yours.
2. The sleep pattern in TFA for a primitive society is different not only from yours, but also from what appears to have been the natural tendency for pre-industrial civilization (at least I Europe) for quite a few centuries https://en.wikipedia.org/wiki/...
3. The study does not and is unable to take into account any of the very long-term effects of less sleep, in terms of possible influences on old-age brain diseases such as Alzheimers or other dementias. A primitive forager doesn't usually live to an age where such things are an issue. The physiological evidence, though, ought to make you pause and think about the fact that you need enough deep sleep in order to allow microchannels in your brain to expand and allow increased flow of cerebrospinal fluid to wash away harmful metabolic byproducts. There's more to sleep than, as was fashionable to think for a while, consolidation of memories into long-term storage. See http://www.sciencemag.org/cont... and several related papers.

** Having compete sleep cycles is more important than the exact time. If you look at various somnograms, you can see that the average sleep cycle (down to the deepest sleep stage then I again into REM) is around 90 minutes long, except the first sleep cycle of the night which is closer to 120 minutes (the 8 hour recommendation corresponds to five sleep cycles). It's worth making sure your alarm is set such that it doesn't wake you during a deep sleep stage of a cycle, because you'll wake feeling worse than even if you had woken up earlier at the end of the previous sleep cycle (during REM). This is why a half hour offset from your usual alarm time in either direction can potentially make a huge difference.

Comment I miss Roger Ebert (Score 1) 184

While, as is the case with any film critic, one is bound to disagree with at least some of the ratings a given critic gives to the movies he reviews, the golden skill of Ebert was that reading his reviews would tell you whether you would like the movie, not just whether he did. While I often agreed with his ratings, there were numerous times I didn't, and in those cases I knew that I'd rate the movie differently merely from reading the review, without having seen the film yet (and every time I did follow up by watching it, my expectations were confirmed).

Comment Re:Yeah, and? (Score 5, Informative) 410

MSF/Doctors Without Borders has been adamant there were no Taliban shooting from the hospital, and MSF has a lot more credibility (they're comparable to Red Cross) than the Afghan police that reported this as supposedly a fire base. Not to mention that the police have a clear revenge motive against MSF, as they are known to have long been complaining that MSF treats patients from all sides, including the Taliban, indiscriminately.

Let's organize this thing and take all the fun out of it.