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User: JoshuaZ

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  1. Re:Ah, yes! on Cockroaches Evolving To Avoid Roach Motels · · Score: 4, Interesting

    No, there's a serious misconception here. Neutral traits can become universal in a population, and frequently do. This is especially likely in small populations (which is part of why bottlenecks matter so much).

  2. Re:Ah, yes! on Cockroaches Evolving To Avoid Roach Motels · · Score: 1

    Mainstream evolution states that each change is an adaptive measure,

    No. Evolution can occur due to neutral drift, founder effects http://en.wikipedia.org/wiki/Founder_effect among other causes. Indeed, the founder effect is a major cause of speciation events.

  3. Re:Ah, yes! on Cockroaches Evolving To Avoid Roach Motels · · Score: 5, Informative

    IDes can accept evolution...the only thing they don't accept is that life on the planet was not in some way fashioned for some particular purpose (which was presumably either already fulfilled long ago, or hasn't been completed yet, or else has been completely forgotten about)

    And now we have yet another variant of ID, and this version is so vague that it isn't even clear what the point is. Sometime there may ave been a purpose at some point- and this is supposed to be a scientific hypothesis?

    But let's look at what the ID proponents actually say.. The primary ID textbook, Of Pandas and Peoples rejected evolution. Of course this is the book that apparently had a litera search and replace from "creationist" to "intelligent design proponents" leading to among other fun bits leading to the infamous ""cdesign proponentsists" http://en.wikipedia.org/wiki/Of_Pandas_and_People#Pandas_and_.22cdesign_proponentsists.22. But let's look at what other ID proponents have said. Michael Behe accepts most of evolution, except for apparent occasional tinkering. His primary example is malaria so you could summarize his views as "There is a designer and he's a bit of a dick". William Demski used to be ok with an old Earth but now questions that and believes in a literal global flood http://en.wikipedia.org/wiki/William_A._Dembski#Southwestern_Baptist_Theological_Seminary_flood_controversy. Paul Nelson is a straight out YEC while claiming that that view isn't common among IDers http://en.wikipedia.org/wiki/Paul_Nelson_(creationist). Etc. Etc. Ad infinitum et nauseam

    ID exists to disguise creationism as something more palatable to be taught in schools or discussed by respectable people. But the proponents aren't very good at having anything like a coherent hypothesis, with each of them trying to decide just how vocal a creationist they'll be and which parts of science they'll reject. ID was made to try to infiltrate public schools under the guise of science, and it shows.

  4. Re:Ah, yes! on Cockroaches Evolving To Avoid Roach Motels · · Score: 4, Informative

    So, most of the other responses here meet most of the major relevant issues. But one thing that's curious is that while some young earth creationists clam they accept "microevolution" what they mean by this is quite hard to pin down. One common claim is that by microevolution one means evolution below the species level. But Answers in Genesis, the world's largest YEC ministry lists claiming that speciation does not occur as an argument that creationists should not use because the evidence for speciation is so strong. http://www.answersingenesis.org/get-answers/topic/arguments-we-dont-use. Now, here's the really neat bit: A variety of ID proponents argue that speciation doesn't happen. There's an interview in Expelled where one of the ID proponents says that speciation doesn't happen. This isn't the only example. So it looks like the ID proponents are frequently even more reactionary than the most sophisticated YECs. That's what happens when you are constructing viewpoints to sound just plausible enough to have an appearance of controversy and not actually trying to figure out the truth.

  5. Re:Not General Purpose on Some Scientists Question Whether Quantum Computer Really Is Quantum · · Score: 1

    Yes, exactly.

  6. Re:Not General Purpose on Some Scientists Question Whether Quantum Computer Really Is Quantum · · Score: 1

    A problem that is intermediate between P and NP is a problem which is contained in NP but is not in P. Note incidentally that the suspicion among most computer scientists and mathematicians is that P is a proper subset of NP.

  7. Re:Stupid Question of the Day!!!! on Some Scientists Question Whether Quantum Computer Really Is Quantum · · Score: 1

    No. Changing the base doesn't make the numbers equal. It just that in base 0 you can't represent any number other than 0. Don't confuse a representation with a number.

  8. Re:Stupid Question of the Day!!!! on Some Scientists Question Whether Quantum Computer Really Is Quantum · · Score: 1
    Regarding unary, you are still confusing the issue of whether one has a representation of the number with whether it exists. These are not the same thing.

    As for base 0, it most certainly can represent all real numbers. In fact, it cannot not do so. But there's no way to convert pi from base 0 to any other base.

    I don't follow. What do you mean?

  9. Re:Stupid Question of the Day!!!! on Some Scientists Question Whether Quantum Computer Really Is Quantum · · Score: 1

    Those aren't bases you can write numbers in in general. That's not that Pi is different, that's that those bases can't be used to represent all real numbers. Pi would still be the same.

  10. Re:If it works - it works on Some Scientists Question Whether Quantum Computer Really Is Quantum · · Score: 1

    P, doesn't have a strict quantum analog that works well. The relevant classes to compare are BPP - polynomial time with small chance of error essentially http://en.wikipedia.org/wiki/BPP_(complexity) )and BQP, same thing but on a quantum computer http://en.wikipedia.org/wiki/BQP.

  11. Re:Stupid Question of the Day!!!! on Some Scientists Question Whether Quantum Computer Really Is Quantum · · Score: 3, Informative

    he reason I ask is that a while back on /. I was educated about the nature of Base-10 computing. Prior to this, I'd spent my entire life thinking that Base-10 WAS mathematics, and I'd had no reason to assume or even imagine that there could be any other type of mathematics than Base-10. Base-10 was the pinnacle of mathematics to me. Then I find out that Base-10 is probably the most efficient to date for our society, but that it is not the only way to count; and that Pi is only Pi because of Base-10.

    No. Pi will be the same regardless of base. The digits of Pi will be different if you write it in a different base, but this is simply a representation, not a change in what the number is. If you do calculations involving Pi in one base and do the same thing with another base and then convert the answer from one to the other you will get the same thing.

    Your general question is a good one. In fact, one of the major things people want to use quantum computers for is to do simulations of quantum systems, which they can do, but which are extremely inefficient (both in terms of time and memory) on a classical computer. So people are looking at problems which are practically not doable on a classical computer. At the same time though, we know that a quantum computer can be simulated on a classical computer with massive resource overhead (essentially exponential slowdown), so we know that anything you can do on a quantum computer you can do on a classical computer if one is patient enough.

  12. Re:Not General Purpose on Some Scientists Question Whether Quantum Computer Really Is Quantum · · Score: 4, Informative

    There are a lot of problems wit this idea. Among other issues, quantum computers, even general purposes quantum computers, cannot as far as it is known solve any NP-hard problem in polynomial time. It is strongly suspected by people in the field that BQP (roughly speaking the set of problems easily solvable on a quantum computer http://en.wikipedia.org/wiki/BQP) does not contain NP. There are also a variety of problems which are conjectured to be intermediate between P and NP which do not have known BQP algorithms. The set of things where a quantum computer can provide a lot of speed up is as of right now, highly specialized. That said, the long-term plan isn't that far off of what you are talking about, using general purpose classical machines to do most computations and only call the quantum computer when one has a problem of a specific type that substantially benefits from it (either from a drop into polynomial time from worse than polynomial time, or just a massive polynomial speedup).

  13. Re:it is and it isnt on Some Scientists Question Whether Quantum Computer Really Is Quantum · · Score: 4, Informative
    This is the sort of thing where it helps to read Scott's post. He specifically discusses the primary claim here:

    Namely, the same USC paper that reported the quantum annealing behavior of the D-Wave One, also showed no speed advantage whatsoever for quantum annealing over classical simulated annealing. In more detail, Matthias Troyer’s group spent a few months carefully studying the D-Wave problem—after which, they were able to write optimized simulated annealing code that solves the D-Wave problem on a normal, off-the-shelf classical computer, about 15 times faster than the D-Wave machine itself solves the D-Wave problem! Of course, if you wanted even more classical speedup than that, then you could simply add more processors to your classical computer, for only a tiny fraction of the ~$10 million that a D-Wave One would set you back.

  14. Re:D-Wave's Dirty Little Secret on Some Scientists Question Whether Quantum Computer Really Is Quantum · · Score: 5, Interesting

    Is there really any difference between quantum entanglement and magic?

    Yes. There's this tendency to view entanglement as spooky, magical, and hard to understand. But this really isn't the case and is more due to the confusing way that quantum mechanics if often taught, as a series of counterintuitive results tacked on to classical physics. If one adjusts one's perspective to think of quantum mechanics more as the consequences of using a 2-norm and looking then at the structure imposed on vectors by unitary transformations, things make a lot more sense. Scott Aaronson(mentioned in the summary above) has a book out recently on just this subject "Quantum Computing since Democritus" which is aimed at explaining these issues to people outside is field but with a comfortable background in other technical fields- essentially no more than some linear algebra, basic probability and complex numbers. The book is highly readable and Scott is a very funny writer, so there are a lot of amusing asides.

  15. Entanglement isn't the only issue on Some Scientists Question Whether Quantum Computer Really Is Quantum · · Score: 4, Insightful

    Scott's blog post and the comment thread there are really worth reading. Entanglement isn't the only issue. A major part of this also is whether the process that the D-Wave machine is doing is anything that is even faster (either in practice or asymptotically) than a classical computer. Right now, the answer for the first is clearly no. Scott describes mildly optimized systems which have been shown to effectively outperform D-Wave at its own problem. The second question- of asymptotic performance is a little trickier but the answer looks like "probably not". It is also worth noting that the D-Wave machines do a very specific optimization problem, of unclear usefulness, and cannot be used at all for many of things that we think of as what one wants a quantum computer for, like Shor's algorithm http://en.wikipedia.org/wiki/Shor's_algorithm to factor integers.

    In fairness to D-Wave though if one thinks of this as essentially a research machine, then not doing as well as conventional systems isn't that much of mark against it any more than very early cars being slower than horses. However, D-Wave is trying to sell these machines commercially. And Scott expresses worry that there's going to be a serious backlash against quantum computing as a whole when the the D-Wave hype bubble bursts. Apparently, D-Wave has now gotten about 100 million in funding, so at least, this is an extremely suboptimal allocation to resources when much more promising academic quantum computer research projects are getting much less money.

  16. But not Great Old Ones on No New S-300 Air-Defense System To Syria Says Russia — But Maybe Old Ones · · Score: 2

    I may have read to much H.P. Lovecraft and Charlie Stross, but when I first read the headline, my initial reading was that Russia would be given shoggoths to Syria. That would have been interesting. It will be interesting to see if any deal does go through, and the fact that Syria wants these is interesting given that the rebels have had little access to aircraft. Syria probably wants it to help prevent intervention in the ongoing civil war.

  17. Re:Too bad for any life on Hubble Discovers 'Planetary Graveyard' Around White Dwarf · · Score: 1

    If there was life there that escaped the current destruction it had to have left millions (or billions) of years ago (since the star has been a white dwarf for a long time and has been being obnoxious to its inner planets for a long time also). That means they would have likely colonized near space (not at all limited to our own solar system). Keep in mind that even the Voyager probes, which aren't even designed to go to other stars will reach nearest stars on the order of 100,000 years. And systems using ion drives and deliberately timed gravity assists could put that in the range of 30,000 years for something to spread out, or a few hundred with nuclear drives of the right type. See for example the summary here http://www.universetoday.com/15403/how-long-would-it-take-to-travel-to-the-nearest-star/.But of course we see no sign of anyone from a nearby system doing much.

    Moreover, if they've had millions of years to spread out, that means that projects like Dyson spheres and ring worlds are obvious things to do. Systematic searches have been done and we're very certain we don't see any Dyson spheres in 300 parsecs (about 1000 light years) http://home.fnal.gov/~carrigan/infrared_astronomy/Fermilab_search.htm. While we can't be as certain, near ring worlds would likely have been noticed by Kepler. Other forms of engineering projects on that scale would be noticed, especially because this is in our back yard. This makes it unlikely.

    In this case, the extremely close nature of the system, and the system's current state means that we can make with a high confidence much higher than just "we saw nothing."

    Who says we'd even notice them with a 150 year delay between their actions and our ability to perceive them?

    I'm not sure what you mean by this. The presence of a delay doesn't interfere with noticing things. It isn't like it is 1 second goes by, wait a 150 years, and then another 1 second goes by. There's just a fixed 150 year delay (just as there's an 8 minute delay from the sun).

  18. Too bad for any life on Hubble Discovers 'Planetary Graveyard' Around White Dwarf · · Score: 2

    These white dwarfs are only 150 light years away. So if any life managed to get off planet and spread out we would have noticed the resulting civilization. We'll probably never know for sure if there was life or even intelligent life on any of these planets because they've been so torn apart by the tidal forces (and very likely anything left on them died out millions of years ago). I wonder if in a few billion years, there might be some other nearby just beginning race looking out to the remains of our solar system and reaching very similar conclusions.

  19. Re:we're not going to run out of oil on Ask Slashdot: What If We Don't Run Out of Oil? · · Score: 1

    This point is really valid. The really relevant issue is the EROEI URL:http://en.wikipedia.org/wiki/EROEI the energy return on energy investment. If this number is much greater than 1 (e.g. gas, some oil, some coal, nuclear) then we get energy out. If this ratio is close to 1 or less than 1, then an energy source is only useful as a storage mechanism. There's a lot of carbon resources left but where the extraction and processing energy would be very high, so the EROEI will be effectively small.

  20. Re:Kessler syndrome is the real worry on Space Junk 'Cleaning' Missions Urgently Needed · · Score: 1

    USA-193 was in much lower orbit with the orbit already decaying so most of the debris burned up. In contrast, the Chinese test was in a stable orbit at the upper end of LEO and so produced a lot more long-term debris. That's not to say that USA-193 was at all a remotely good thing, but it was not nearly as bad.

  21. Kessler syndrome is the real worry on Space Junk 'Cleaning' Missions Urgently Needed · · Score: 5, Informative

    The worst case scenario is a Kessler syndrome event http://en.wikipedia.org/wiki/Kessler_syndrome. In this situation, a bad collision in low Earth orbit creates enough debris to trigger a series of collisions, each creating an expanding debris cloud. This could take most LEO satellites in a matter of days, and would render much of LEO effectively unusable for years. Part of the problem is that while there are a lot of possible orbits, the set of orbits which are both cheap to get to and practically useable is a much smaller set. And those orbits are almost precisely the orbits with a lot of debris. Right now, satellite are required to be able to move to either graveyard orbits or to be safely disposed in the atmosphere, but there are a lo of older satellites that were launched before any such requirement. And even with such plans, launches inevitably produce a few debris items with each launch, and satellites occasionally shed things. The early Delta rockets were very bad at producing a lot of debris, which contributed much of the current problem. Thee 2007 Chinese satellite test http://en.wikipedia.org/wiki/2007_Chinese_anti-satellite_missile_test very much didn't help matters, and produced a massive still expanding cloud of debris. On the bright side, non-LEO orbits like geostat are still clean.

  22. Re:I thought it was well known on Apple Bans Sale of Comic Book On All iOS Apps Over Gay Sex Images - Update · · Score: 1

    Yes, now that what has happened has been clarified, it is clear that all of this (including TFA) were not describing the situation accurately. The analysis I gave rests on the now shown to be incorrect premise that Apple was the one doing this.

  23. Re:I thought it was well known on Apple Bans Sale of Comic Book On All iOS Apps Over Gay Sex Images - Update · · Score: 2

    That almost makes it sounds like it is gender discrimination rather than orientation discrimination.

  24. Re:I thought it was well known on Apple Bans Sale of Comic Book On All iOS Apps Over Gay Sex Images - Update · · Score: 5, Informative

    You are missing the central point: This doesn't even require reading TFA, just the summary. Previous issues of Saga had as graphic or more so heterosexual situations. Yet they were not banned, nor have they been banned. Saga 1-11 is still available. So the problem here is that heterosexual and gay are being treated differently.

  25. Re:The context of the case on Build a Secret Compartment, Go To Jail · · Score: 1

    Right, the sentence was clearly disproportionate. This is connected to a separate problem in our judicial system- the frequent use of giving people shorter sentences if they cooperate in getting others. In practice this frequently means that the actually most guilty people can cop a plea to screw over the less important or less culpable conspirators.