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Comment: Re:Shot in the back (Score 1) 280

What if the magazine fell out and the ammo sprayed all over the ground?

Are your rifle magazines made out of thin glass?

Just curious, because the ones I use don't shatter when they hit the floor, and I've never actually heard of one spraying ammo all over the ground from being dropped....

Comment: Re:Falsifiability (Score 2) 231

by Artifakt (#48230233) Attached to: High Speed Evolution

In Biology, there's the concept of Stochastic Mutation. It's most commonly attributed to viruses, for example HIV is a known stochastic mutator. In these cases, some (not all, just some), types of cell mutations occur, where there's no selection pressure - the virus changes its protein coat in one of several ways (4 for HIV), and type B is just as likely to mutate back to type A or into Type C or D, as to stick where its at. In equilibrium, none of the protein coats is preferred by natural selection, and there's no pressure for one type to come to dominate. HIV also undergoes non-stochastic mutations, just like (we think) everything else with a genetic code does, and stochastic mutation has been studied for many other viruses and probably happens in more complex species.

          That's the point - evolution is essentially a two part theory, a synthesis of Mendel's genetics including mutation, and Darwin's natural selection. Cases where all the organisms subject to selection pressure are identical, are not evolution*, and cases where the organisms are not identical but there's no selection pressure applied are not evolution either, and so there really are at least two categories of biological change which are not evolutionary. It's just that 'cases where there's no selection pressure' pretty much discribes some sort of paradise where nothing dies or is limited in how often it reproduces, so there are not a whole lot of known examples of that, especially over a long term, and it would be pretty expensive to create such an environment over a short term.

* If you had some organisms, and they have 0% chance of mutating in the particular way that responds to that particular selection pressure, then you could say that they are identical in that respect. Imagine for example a bunch of Leopards suddenly introduced to an environment where there are abundant fish in deep subsurface pools which can only be reached through narrow fissures. There's really no selection pressure sufficient for those Leopards to start adapting into creatures that can squeeze through six inch wide cracks and use their gills to dive deep enough to catch those tasty fish. All the Leopards are effectively identical, in that they are identically unsuited to take advantage of the new factor in their environment, tasty deep dwelling cave fish. However, I get a feeling you would reject generalizing that sort of example into one of the cases such as you are asking for, so let's just stick to Stochastic Mutation

Comment: Re:Falsifiability (Score 1) 231

by Artifakt (#48230061) Attached to: High Speed Evolution

Darwin himself was careful to specify what he was arguing for - His first book was, after all "On the Origin of Species", not "On the Origin of Life". His theory is about how existing life divides into distinct groups, and (in a modern version of his phrasings), why species are 'distinguishabe sets with fuzzy boundries', and doesn't really touch on where the first life forms came from, one way or another. We could start from some assumed single primative life form, or imagine a world where there was somehow only one very complex life form, say existing as millions of identical clones, and speciation would still occur, and the mix of species, once formed, would still change over time, according to the theory.

Darwin made predictions which were testable, and could have been falsified - for just one, there's a prediction that the genetic code (unknown at the time), wouldn't allow unlimited blending of traits (Mendel published the first proof of this as a general fact, and Crick and Watson's work in actually discovering the code confirmed it was the sort of coding that didn't allow blendable traits). One problem I see with the "anti-evolutionists", is they keep talking like 'testability' means we have to have two copies of Earth and run the great experiment twice, or there's no testability at all, when a little real familiarity with Darwin's work reveals lots of testable predictions of the same sorts we see in many other works of science. It's sort of like how early critics of Special Relativity dismissed the 1919 solar eclipse test as not sufficient by itself, and people who wanted to reject Relativity on any and all grounds turned that into its not being a test at all in popular discussions. I suspect there's real debate needed about just what the limits of the Theory of Evolution's predictions are, but those debates need to be among people who know what the theory does or doesn't predict, what testability itself means, and other fundamental ideas.

Comment: Re:Falsifiability (Score 4, Insightful) 231

by Artifakt (#48229885) Attached to: High Speed Evolution

It's not quite that simple, but you could probably simplify it to a few basic steps, like:
Is there a coding mechanism for heredity? - Yes, the genetic code.
Is there a way to generate new code? - Yes, mutation.
Does that code allow unlimited blending? - No, if it did the two sexes would completely blur together, among many other lesser examples.
Is there selection for fitness? - Yes, not everything gets to reproduce as much as it attempts to, and at least some of that is attributable to being "unfit".

Basically, people can point to examples where limited blurring may occur, or being taken out of the gene pool may have nothing to do with fitness (all dinosaurs are equally unfit to survive a 5 mile wide asteroid strike), or many other such factors, but they aren't really offering any effective criticism of evolution unless they want to claim things like selection or mutation never happen.

This is also why what Darwin did was science. His publication made several testable predictions - that there would be a genetic code, that the code could be altered on occasion, and that it would not allow unlimited blending of traits.

Comment: Re:my thoughts (Score 4, Informative) 352

by Artifakt (#48219091) Attached to: NY Doctor Recently Back From West Africa Tests Positive For Ebola

Some types of mutation are fantastically unlikely - by one account, Ebola would have to mutate into a form that only weighs about 20% or even 10% of what it now does, change from a long, twisted rod to something more like a sphere, and switch the conditions it actually grows under from inside the bloodstream to in the alveolar structures of the lungs to become the sort of threat some people are worried about. There are big differences between viruses frequently mutating and that mutation leading to fast evolutionary selection, but I've tried to explain that on Slashdot too many times to keep hammering at that particular type of ignorance - some people just need to sit down and read a whole good college textbook on Evolution. It may be somewhat reasonable to worry that some mutation in the direction of drug resistance is likely, especially if we don't get this strain under control quickly, but some people are basically describing having a smallish frilled lizard sneak into the country on a piece of driftwood, and six months later, it's stomping buildings flat and breathing radioactive plasma on Mothra, and those same people are too busy spreading rumors to learn anything at all. As they panic at the drop of a hat, people who are actual experts (and not just armchair biology hackers like me) are getting very afraid to say anything at all, because when they give an honest answer that sholdn't cause panic, and might even be a bit reassuring, they expect to be misquoted as saying Ebola will make the Nemesis black hole wander into the inner solar system early and reverse all our magnetic poles, and Raptor riding Jesus will come back and eat our heads, so panic now and avoid the rush!!!

Comment: Re:Overly broad? (Score 4, Interesting) 422

by Artifakt (#48183875) Attached to: Soda Pop Damages Your Cells' Telomeres

The 40 to 55% of HFCS that isn't Fructose is Glucose, which triggers insulin production immediately when it reaches the small intestine and is transported into the bloodstream before the insulin reaches it - Insulin is then needed to transport the glucose out of the bolldstream and into muscles and other tissues. Sucrose has to be cleaved first into glucose and only starts triggering insulin production after cleavage by other enzymes. This means, qat the very least, that Sucrose gets farther into the intestine before triggering insulin production, and that the rate of production is limited by the rate at which the sucrose is split and not the much faster rate at which glucose enters the bloodstream. I really don't see how you can call those two processes identical. Note I'm not saying that its been proved the differences in how high and low insulin levels and blood sugar levels get necessarily means there's a difference in health consequences, but its certainly not impossible just because of the fact both forms of sugar get to the same organ before digestion. And what about the part that is Fructose? That's certainly dealt with separately.

Comment: Re:Units hurt the brain (Score 1, Insightful) 74

by CrimsonAvenger (#48182025) Attached to: NASA Cancels "Sunjammer" Solar Sail Demonstration Mission

Being a European i have no clue how much a pound is, and probably British and US pounds differ too. Ok, i could guess a pound is about half a kilogram. Still makes no sense to mix them up in a scientific article.

Wrong guess, minus five.

Hint: the pound is a unit of FORCE, the kilogram is a unit of MASS. It makes no more sense to measure thrust in kilograms than it does to measure distance in square meters.

If you really want to have consistency, they should have measured the thrust in newtons, NOT in kilograms.

The fact that Europeans (at least one of them) don't know their own measurement system any better than that is appalling....

Comment: Re:Article or link (Score 1) 113

Most modern judicial systems (US the notable exception) recognize that when you've done your time you have "paid" your debt to society - and should have a chance to start over.

Yeah, just because you did time for embezzling doesn't mean you should be denied a job as a CFO or Banker....

Comment: Re:Region-Specific (Score 1) 86

by CrimsonAvenger (#48175691) Attached to: India Successfully Launches Region-Specific Navigation Satellite

So you make a regional system by setting up the orbits so that there are always 3-4 satellites visible from the region of interest. Occasionally you will be able to get a fix elsewhere in the world, but usually not.

Actually, while it's generally pretty trivial to make sure 3-4 (5+ would be better) are visible from any given point on Earth, it's rather harder (read: nearly impossible) to make sure 3-4 are visible from any point in India but NOT from any point outside India.

Unless the satellites are in geosynchronous orbits, of course, but then you're not going to have the separations you need for a good solution.

Realistically, India needs an array like GPS or GLONASS, not just seven satellites.

Comment: Re:Why Cold Fusion (or something like it) Is Real (Score 2) 349

by Artifakt (#48174785) Attached to: The Physics of Why Cold Fusion Isn't Real

It's possible there are as yet unknown natural laws. It's even possible that there are natural laws our species is just too dumb to discover, ever. But the chance of undiscoverable laws is lower than the more general chance of as yet undiscovered laws.
            In the same way, the chance that there's an as yet undiscovered law which applies to this particular technology, and which has certain properties making it at all likely it gets inadvertently followed sometimes is possible, but is an accumulation of low probablility circumstances, and so has very low overall likelyhood. It's generally more likely that any undicovered laws will be ones where they consistently block getting the technological configuration right. For a simplified example, if there's some undiscovered property of, say, Tungsten, then it's likely to become apparent when people note that all the claims for success come from experiments where tungsten was used for a particular stage of the process in a particular way. There's much less chance that simply having a certain mass of Tungsten within a certain number of feet of the device, whether it's made into a part of the apparatus or light bulb filaments, will make the experiment very likely to succeed in either case.
        Try to describe a hypothetical law that works in such a way it is very hard to spot a pattern or regularity that will lead the researchers to really formally formulating that law, but makes a big enough difference that it determines general success or failure much more than many other variables. Try to craft such a genuinely new law for explaining anything, from apiary colony collapse disorder to zebra camoflage evolution*. I'll bet this results in a very long, convoluted law to explain all the conditions. That's what usually happens with novel approaches - sure every once in a while one pays off big time, but not every discovery is Special Relativity. If you end up with a long formulation, full of various clauses which make it fit all the observations, then what you have is a chain of things, and if any link of that chain is wrong, the whole formulation collapses. If a chain is really only as strong as its weakest link, then a very lengthy chain of logical inferences is a chain with a very low probability of being right.

* why do Zebras have stripes when one of their predators in roughly the same size range has polka-dots (Leopards)?, and another one even closer to Zebras in size is solidly colored (Lions)? Try to develop a new law relating to natural selection that rules out any possibilitys that this is simply happenstance, and yet that doesn't predict what sorts of camoflage any other species should display in case some of the facts don't fit that case.

Comment: Re:What equations? (Score 2) 89

by Artifakt (#48171085) Attached to: How Curved Spacetime Can Be Created In a Quantum Optics Lab

Are they talking about general relativity equations?
That's included, but I think the article and summary are actually getting it right for once. The equations in question are ones that reconcile GR with Quantum Mechanics, and that, in general, means variations on various String or Brane Theories, and quite possibly specifically Supersymmetry, if that's not being completly discarded by the researchers just because CERN is finding preliminary evidence that the simplest and lowest energy Supersymmetry model doesn't work. It's possible some alternatives to those models can also be tested and refined or dismissed, but either way, we really are looking at math where complexity increases result time very, very rapidly. Here's a link for an example of some math used for both Supersymmetry and more general String Theory calculations - If you look at the section specifically about "Stringy theories" calculations, there's a good example of a formula that's obviously, by simple inspection, prone to grow very quickly with added terms for more complex situations, and there's some other quite good examples in the lead up to that section.

Lie superalgebras of string theories

(Note: Paper is 22 pages in PDF, and is NOT behind a paywall).

Take care of the luxuries and the necessities will take care of themselves. -- Lazarus Long