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User: Baron+Eekman

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  1. Re:Nice hypothesis. Now to test it. on Grand Unifying Theory of High-Temp Superconducting Materials Proposed · · Score: 2

    I'm sorry, but I fail to see how it is very testable. I very much like the main conceptual point "it is the antiferromagnetic interaction that is universal while it is the fermiology that is not". To this end, the authors pose (definitely not derive in any way) an extremely simplified model, that nevertheless is seemingly capable of accomodating the wildly varying behaviours we see in unconventional superconductors. It is consistent with many observed properties. However, perhaps due to its versatility, to me it doesn't seem to have much predictive power, and certainly not quantitatively. It may be perhaps be falsified by some new class of materials, but even that seems not very straightforward to me.

  2. Re:PNAS contributed paper on Grand Unifying Theory of High-Temp Superconducting Materials Proposed · · Score: 1

    They put the paper on arXiv before publication, so I guess exclusive is not as restrictive as it may sound.

  3. arXiv link on Particle Physicists Confirm Arrow of Time Using B Meson Measurements · · Score: 5, Informative

    Come on people, how hard is it to include the arXiv link? Just google the title, it's usually the first hit.
    http://arxiv.org/abs/1207.5832

  4. Re:The challenge of getting past c on Mathematicians Extend Einstein's Special Relativity Beyond Speed of Light · · Score: 2

    Indeed. The fact that they didn't put it on arXiv is another indication it's probably not much more than hype.

    Now that I think of it, how awesome is this? Being published in a journal but not on arXiv is more suspicious than the other way around.

  5. Re:How to use the DOI system ? on Should Journalists Embrace Jargon? · · Score: 1

    DOI is only a link to the official address of a paper, it is not a repository.

  6. Re:"...more please"_agree on Interviews: Giovanni Organtini Answers About the Higgs and LHC · · Score: 1

    Yeah, sorry, it's both hadrons and leptons.

  7. Re:Wait, phi^4 what? on Interviews: Giovanni Organtini Answers About the Higgs and LHC · · Score: 1

    That question is a bit difficult to answer. Let me try a few, hopefully one of them helps you.

    1) It's there because it works. A large part of high-energy theory is what is called model building, where people build models that at the least agree with previous knowledge and are internally consistent. Hopefully they also explain something not explained before. Such a phi^4 potential term is very natural to try (cannot elaborate on that here), and gives the Higgs boson and mechanism as we know it, and thus the Standard Model.

    2) The phi^4 is the reason for the self-interactions, agreeing with observation.

    3) This one is complicated. The Higgs potential energy contains two terms, one proportional to phi^2 and one proportional to phi^4. In quantum field theory, terms quadratic in a field correspond to the mass term for that field. Without the phi^4, the Higgs would be a free, non-self interacting particle. Moreover, the whole reason why the Higgs field can give mass to other particles, is because its mass term is negative! This is called "spontaneous symmetry breaking", a hugely important concept associated with phase transitions. You can picture it as follows: a ball in a valley will roll to the bottom and stays there. The negative mass (potential) term however causes the middle of the valley to rise to a small hill (local maximum). The ball will now want to roll down away, but any direction is equally good, and one is chosen randomly or "spontaneously". The phi^4 term is necessary to make the valley curve upward again, so that the ball does not roll down indefinitely. Thus to have any model with spontaneous symmetry breaking (which agrees with the fact that the Higgs field permeates all of space), a phi^4 term is necessary to make the potential energy bounded from below.

  8. Re:"...more please"_agree on Interviews: Giovanni Organtini Answers About the Higgs and LHC · · Score: 1

    Just want to mention that for all the "ordinary" particles, that is the hadrons, the Higgs contribution is only part of their mass. Only the mediators of the weak nuclear force, the W- and Z-gauge bosons, get all their mass from the Higgs mechanism, which is the reason why this force is short-ranged, as opposed to for instance the electromagnetic force mediated by photons, which is (infinitely) long-ranged.

  9. Re:Wouldn't it be great... on Volunteers Use Annular Eclipse To Measure Sun More Accurately · · Score: 3, Informative
  10. Re:This article says nothing. on Cambridge Scientists Create Huge Quantum Particles · · Score: 5, Informative

    The expression "quantum fluid" can be misleading.

    What they did here is make a system of coherent "polaritons" just as laser light is a bunch of coherent photons/light waves. As mentioned in the article abstract, a polariton is some combination of a photon (light particle) and an exciton. In turn, an exciton is a bound state of an electron and a hole from the semiconductor. (A hole is the 'vacant' positive charge created when an electron is removed, and may for all practical purposes be regarded as an anti-electron within the semiconductor.) If I understand correctly, the novelty in this work is not making the polariton condensate but the visualization of it. In that sense, the summary if way off.

    This is surely not easy to grasp for the layman. What does this imply? As parent mentioned, making coherent quantum states or matter is a standard affair by now, and research focuses on extending our capabilities on all levels. It is necessary for our understanding of the fundamentals of quantum mechanics and how many particles conspire to make laboratory but also everyday matter. The practical possibilities for making devices out of "quantum fluids" is severely limited, since you almost always need extremely low temperatures to produce them. Only superconductors come close.

  11. Re:Seems like a lot of effort on Dutch Government To Tax Drivers Based On Car Use · · Score: 1

    Parent is correct.

    This system ("rekeningrijden") is being proposed for years now. While it is certainly very fair--polluter pays, and pays more during rush hour--it faces two large problems:
    - Technical implementation. There have been so many public sector IT fails now, most recently with the public transport Oyster card, that everybody is getting really reluctant to introduce another technical solution to a social problem;
    - Privacy concerns, as many commenters here already alluded to. Used to be not a big issue for most people the Netherlands, steadily gaining attention over the past few years.

  12. Re:Free like beer or free like speech? on Indie Film Premieres On BitTorrent Before Cinema · · Score: 3, Informative

    The Blender showcase film Sintel has all source needed to render it freely available.

  13. Re:Misleading title on Fermilab Confirms Evidence of 4th Flavor Neutrino · · Score: 3, Interesting
    The finding that the oscillations of anti-neutrinos behave differently than those of neutrinos is very interesting though, even when "very suggestive". It may lead to an explanation of why we see far more matter than antimatter in our universe. That should have been the headline, like here.

    I would guess that the research is quite solid, the press release is overhyping as usual.

  14. Misleading title on Fermilab Confirms Evidence of 4th Flavor Neutrino · · Score: 5, Informative
    There is no "Evidence of 4th Flavor Neutrino" here.

    What has been found is an excess of certain events (namely anti-muon-neutrino to anti-electron-neutrino oscillations), where "excess" is defined relative to the current best-established model. So what this experiment (if correct) shows, is that the current model is not good enough.

    From the PRL paper:

    The source of the excess remains unexplained, although several hypotheses have been put forward

    One of those hypotheses is additional neutrino flavours, but this finding is not evidence for that.

  15. Re:Oh, just great on Researchers Find a 'Liberal Gene' · · Score: 1

    Sure, but from the paper's wording, one can definitely not infer that "a specific gene that predisposes people" has been "identified". A gene has been identified, indeed, but it may have a correlation with one's political views. Absolutely no need to beautify this, but that's what's done all the time nonetheless. It causes people to misunderstand the actual findings, like this.

  16. Re:Oh, just great on Researchers Find a 'Liberal Gene' · · Score: 5, Informative
    Here is one of the authors' home page. Here is the actual paper.

    From the discussion section at the end (emphasis mine):

    For most traits, the effects of individual genes are too small to stand out against the combined influence of all other genes and environmental factors. Thus, our p-value of 0.02 on a sample of 2,000 individuals should be treated cautiously. The expectation in genetics is that only repeated efforts to replicate associations on independent samples by several research teams will verify initial findings like these. Thus, perhaps the most valuable contribution of this study is not to declare that ‘‘a gene was found’’ for anything, but rather, to provide the first evidence for a possible gene-environment interaction for political ideology.

    Contrast this with TFA:

    The study's authors say this is the first research to identify a specific gene that predisposes people to certain political views.

    I hate it when this happens, makes people dumb.

  17. For great justice on TI vs. Calculator Hackers · · Score: 0

    Turn off every sig

  18. Re:For fuck's sake! on Dutch Gov. Wants To Tax Online Media To Fund Print · · Score: 0
  19. Re:Legalize it? on US Open Government Initiative Enters Phase Three · · Score: 1, Informative

    I live in Amsterdam. I feel extremely safe. Most people here shrug when one criminal shoots another, as long as no innocent people are involved.

    Most criminal activity is probably drug-related, but that's because hard drugs like cocaine are still illegal, and handling large quantities of marijuana, necessary if you want to make a business selling it semi-legally, is as well. International treaties and pressure prevent legalization and thereby decriminalization.

    Oh, and another thing: crime rates are higher in big city, is that surprising?

  20. Re:Original research? on 12 Small Windmills Put To the Test In Holland · · Score: 1

    To parent and sibling above:
    There's usually a link to a news or scientific article somewhere. Here's a poster personally drawing conclusions as "ridiculously low yields", what good does that do? So I disagree: this is not news.

  21. Original research? on 12 Small Windmills Put To the Test In Holland · · Score: -1, Flamebait

    What is this doing on the front page?

    The summary links to a report on an experimental setup. The poster draws his unverifiable conclusions. On Wikipedia we would say "no original research, please".

    The costs are obviously high, as these are still in developmental stage. Most of the turbines performed below the expected yield, but for example the "Skystream", which was one of the cheaper models, output 2109 kWh, where 1360 kWh were expected. The test can easily be claimed to show this was a success.

  22. Re:*Believing* isn't the correct verb on Darwinism Must Die So Evolution Can Live · · Score: 1
    English is indeed not my native language, but still I think scientists working in evolutionary biology would not refer to themselves as "believing in evolution".

    I'm curious, if you think "believe" means "to think without evidence", what would you put in "Scientists __________ in evolution"? Or do you not have a word that encapsulates the concept of "see it confirmed over and over again, so accept it as a very good theory."?

    Actually, I would say yes to this, because "believing" can imply so many other things (these days?).

  23. Re:*Believing* isn't the correct verb on Darwinism Must Die So Evolution Can Live · · Score: 5, Insightful
    Actually, GP was spot on.

    Scientists don't believe in evolution, they see it confirmed over and over again, so accept it as a very good theory. Therefore religion is not an alternative for evolution, it's a whole different game.

    Nobody will oppose that "there are particles", but what a particle actually is, no one can really say.

    I work in quantum physics, and to me, an electron is just a bunch of so-called quantum numbers, such as mass, electric charge etc.

  24. Mod parent up on Trick or Treatment · · Score: 1

    The book is amazingly good, concise and explanatory.

  25. Re:SSL from now on!!! on RIAA To Stop Prosecuting Individual File Sharers · · Score: 1

    Wasn't there a case when the RIAA downloaded something, tried to sue, but it failed, as they (RIAA) effectively owned the copyright to what they were downloading, so neither of the parties were infringing on anything?