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User: Roger+W+Moore

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  1. Re:Not your "everyday" Neutrino on Scientists May Have Detected Neutrinos From Another Galaxy · · Score: 1

    Yes - you have to go a above 1 PeV to get a decent chance of an interaction in a human - I did say "really high"!

  2. Not your "everyday" Neutrino on Scientists May Have Detected Neutrinos From Another Galaxy · · Score: 5, Informative

    The neutrino is going to go straight through you with a 99.99999% probability.

    Actually that is probably not quite true. For the vast majority of neutrinos you encounter on a daily basis (from radioactive decay, relic Big Bang neutrinos, solar etc.) you are completely correct. Indeed for these, as the article states, they will pass through the earth without blinking.

    However PeV neutrinos are NOT your everyday neutrino. These guys have such an incredible energy (over 100 times the proton energy in the LHC) that the earth is actually opaque to them. In fact if you look at the IceCube analysis they look for down going neutrino i.e. ones coming in from above despite the problems with the back grounds from cosmic rays. This is because they cannot look for neutrinos which have passed through the earth because, at these energies, there will be none!

    The reason for this is that neutrinos interact with matter through W and Z bosons. These have a mass ~80 to 90 times the mass of a proton. The reason that normally neutrinos do not interact is that there is insufficient energy to make a "real" W or Z in the interaction and this heavily suppresses the chance of it happening (due to quantum mechanics it can till occur though). Above a PeV the energy becomes high enough that this energy suppression effect gets a lot smaller and so the chance of interacting becomes a lot higher - eventually becoming slightly stronger than electromagnetism at really high energy when real W's and Z's can be created.

    So the upshot of this is that a really high energy neutrino might actually have a reasonable chance of interacting in your body and the article is completely wrong when it describes the earth as basically transparent to these neutrinos...although it is an understandable mistake given that it is transparent to most neutrinos.

  3. Re:in joules. please on Scientists May Have Detected Neutrinos From Another Galaxy · · Score: 1

    We don't know what the mass of a neutrino is, but we do know they're light (m
    Not quite - IceCube looks for muon neutrinos and these have a mass limit of 0.19 MeV/c^2. The lowest mass constraint is actually 2 eV/c^2 for electron anti-neutrinos from tritium decay spectrum measurements.

  4. Re:First Law of Thermodynamics on LHCb Experiment Observes New Matter-Antimatter Difference · · Score: 1

    The big bang as we currently assume it is clearly not symmetric under translation in time.

    Careful - I have heard some speculation from cosmologists that time may have existed prior to the Big Bang in which case energy may well have been conserved. However if the Big Bang created time and without time there is no concept of energy then obviously in these circumstances energy cannot be conserved. However my response was to the OP's claim that thermodynamics had no law about energy conservation which is clearly untrue.

  5. Re:equal amounts at the beginning of the Universe on LHCb Experiment Observes New Matter-Antimatter Difference · · Score: 1

    So the number 2 does't exist? Infinity doesn't exist?...Physical reality is only a tiny subset of much larger reality that scientists are generally clueless about.

    Perhaps I am being overly scientific here but that "larger reality" is in your head, which is a complex physical system operating in our physical reality and hence any thought you may have is part of our physical reality - it's the quantum state of your brain. Hence the number two represents an abstract concept designed to be relevant to our universe. Frankly if you have no space and no time then I'm not convinced that the number 2 does exist or have any meaning - 2 what?

    Clearly the universe came from somewhere but that is the only physical evidence that reality is more than our universe. Calling your own thoughts and concepts a "larger reality" is false because you can easily conceive of things that are not real. Perhaps whatever came before the Big Bang allowed for the existence of mathematical concepts as we understand them but, without evidence to that effect it is nothing more than supposition which does not make it real.

  6. Re:equal amounts at the beginning of the Universe on LHCb Experiment Observes New Matter-Antimatter Difference · · Score: 2

    It's not just time: how does anything exist if there is no space?

  7. First Law of Thermodynamics on LHCb Experiment Observes New Matter-Antimatter Difference · · Score: 3, Informative

    Actually there is. Of course it is only interested in thermal energy but nevertheless it is there. One of the most beautiful bits of mathematics, Nöther's Theorem, shows that for any symmetry there must be a conservation law (or vice versa). For energy the cause of the conservation law is that the laws of physics are all symmetric under translation in time i.e. the laws of physics today are the same as they were yesterday. So while the reason for energy conservation has nothing to do with thermodynamics it is still stated as its first law.

  8. Good question! on LHCb Experiment Observes New Matter-Antimatter Difference · · Score: 5, Informative

    How do we know this?

    We know this by looking for gamma rays produced by matter/anti-matter annihilations. The solar wind does not annihilate with out atmosphere so we know the sun is made of matter. This same wind does not annihilate with the interstellar medium in the galaxy so that is made of matter. No other star has visible annihilation lines with this medium either so we can be sure the entire galaxy is made of matter. Further out out galaxy does not create annihilations with the medium in the local super cluster of galaxiesand neither does any other galaxy so we know that the local super cluster is all made of matter.

    To go further afield is harder since at this point the distances rule out detecting gamma rays from the incredibly sparse intergalactic medium (at least this was true several years ago - perhaps astronomers can do better now?). So instead what you can do is look at galactic collisions. No colliding pair of galaxies emits gamma radiation consistent with annihilation events so either the universe is really perverse and somehow no pair of colliding galaxies is ever a matter/antimatter pair OR there are no anti-matter galaxies out there to collide with. So while it is impossible to rule out that there might be one or two anti-matter galaxies hiding in some distant corner of the universe there are clearly far, far more matter galaxies than anti-matter ones.

  9. Re:Jules Verne on Ask Slashdot: Science Books For Middle School Enrichment? · · Score: 1

    Mod this UP.. ."Journey to the Center of the Earth".

    Yes - because we really want school kids to learn in their science class that the centre of the earth is populated by dinosaurs.

  10. Literature NOT Science on Ask Slashdot: Science Books For Middle School Enrichment? · · Score: 2

    Reading science fiction might be a great exercise in English literature but it is not, in any sense of the subject, science. Frankly I despair for the kids' education if reading science fiction is their science teacher's idea of enhancing their science education. If you want to give them extra credit why not have them design an experiment to measure the acceleration due to gravity? or if they have done Hooke's law calculate the maximum height they can safely drop an egg attached to a spring from without the egg breaking. For biology you could do things like have them collect leaves and identify 10 species of plant X (where X could be trees, grass, etc.).

    If you want to stick with books then at least insist on factually science books e.g. "Too Hot to Handle: The Story of Cold Fusion" by Frank Close for a real life story of science gone wrong. There a huge variety of books in similar veins ranging from the stories behind great scientific discoveries to books explaining modern scientific concepts to lay people. So please, please don't have them read fictional stories for science - I love science fiction myself but calling it science is the same as calling The Lord of the Rings history.

  11. Research != Programming on Terrible Advice From a Great Scientist · · Score: 1

    No he is not right. Research is not like programming. When coding a program the basic framework already exists: someone comes up with an idea and then someone else can write all or part of the code. Now imagine doing the same with research: someone does an experiment and then another person analyses the data. Chances are that this analysis will be worthless because they have not accounted for all the systematic errors and corrections due to nuances of the experiment itself. To analyse the data you need to have an incredibly detailed knowledge of the experiment and understand it well enough to figure out all the corrections needed during the analysis. In reverse you also need to design the experiment to minimise any biases and effects on the analysis.

    Worse his singling out of a "few disciplines" clearly shows how ignorant he is of fields outside his own. ALL of physics, not just particle and astro, needs what he would call "advanced" maths: calculus was invented to describe newtonian mechanics and quantum mechanics requires that you solve partial differential equations to understand what is going on: indeed using intuition with QM is not likely to end well. Chemists need some level of understanding of QM since this is what governs reactions. Earth scientists need "advanced" maths for seismology and climate modelling and lets not even mention all of computer science (although perhaps he regards this as information theory).

  12. This would make your policies so small that nobody would be quite certain what they were and every time you did manage to pin one down you'll get a random result based on the observer...sounds just like a political party.

  13. Re:Oh Canada... on Canadian Official Escorted From House For Others' Facebook Comments · · Score: 1

    We may be getting slightly more insane each year but that does not mean that we are closing the gap with the US.

  14. Re:...not only Higgs "coincidence" on Higgs Data Could Spell Trouble For Leading Big Bang Theory · · Score: 4, Informative

    No - the LHCb data has ruled out large swathes of SUSY parameter space but has certainly not come close to ruling out SUSY. You can hide SUSY from indirect searches like Bs->mu mu by e.g. making SUSY have the same flavour symmetry as the Standard Model. So these searches are incredibly useful at limiting the SUSY parameter space but to really know whether SUSY is there you have to look for direct evidence. I'll start being sceptical of SUSY if after 2-3 years of running the LHC at 13-14 TeV we still see nothing...at that point we will start to have interesting questions about Dark Matter as well if we have not seen it.

  15. ...not only Higgs "coincidence" on Higgs Data Could Spell Trouble For Leading Big Bang Theory · · Score: 4, Interesting

    It's not a cosmic catastrophe so much as a physics one, although I'd prefer to call it a physics "opportunity"! Having found the Higgs we already know that there is now an incredible precarious balance even within the Standard Model. The Higgs is a fundamental scalar particle which is a radically different beast from any other fundamental particle we know of. One of the strange properties of the Higgs is that there are corrections to its mass which scale with energy squared.

    This might not sound like a big deal but quantum mechanics means that even at low energies these high energy corrections to the Higgs mass are important. The question then becomes "what energy is our current knowledge of physics good to". Well if we look at the Standard Model of particle physics it is missing gravity so, at the scale where gravity becomes important (about a million billion times higher in energy than the LHC) we know the SM breaks down.

    The problem is that this means the Higgs mass is corrected by a series of terms each of which is ~32+ orders of magnitude larger than the mass itself. This means that you need a cancellation to better than one part in ~10^32 by chance. This is about the same chance as winning the UK national lottery every week for 4-5 weeks in a row or tossing a coin and having it come up heads over 100 times in a row. If either of these events actually happened nobody would believe they happened by chance - there would be investigations into how someone managed to cheat the lottery or you would want to inspect the coin to make sure it did not have two heads.

    There are solutions to this conundrum: Supersymmetry makes all the corrections to the Higgs mass cancel precisely (above some energy scale) and Large Extra Dimensions lowers the scale where gravity becomes important considerably. What would be interesting to know is whether these solutions to the fine tuning problem we have in the Standard Model also solve the fine tuning which this paper suggests that cosmology also has.

  16. Aurora Watch on Aurora Borealis Likely To Be Visible In Southern NY and PA Tonight · · Score: 2

    This website will send you emails when Aurora are likely - it's based in Edmonton so it works best for northerly locations with the same magnetic latitude but when the storm hits you should see the chance for Auroras spike in Edmonton as well - and you can sign up for an email if you don't want to watch the site.

  17. Corporation vs. Government on Eric Schmidt: Regulate Civilian Drones Now · · Score: 2

    Corporation gets out of control, "BUY THIS BUY THIS BUY THIS!" Government gets out of control, loss of privacy, freedom. Death.

    That depends on the corporation and whether they act in concert with other corporations. For example it is quite easy to imagine corporations causing a loss of privacy: tracking cookies, selling consumer habits, lack boxes in cars etc. Loss of freedom is admittedly restricted to particular freedoms: secure EFI, DVD region locks, DRM etc. Death is rarer still but not unheard of: pollution, unsafe devices and substances e.g. asbestos, Bhopal etc.

    So don't kid yourself: out of control corporations could be just as bad as an out of control government. The only reason they tend not to be is that corporations can be brought to account by government before they get completely out of control whereas an out of control government is far harder to bring to account.

  18. ...and no short term memory on "Choice Blindness" Can Transform Conservatives Into Liberals - and Vice Versa · · Score: 1
    Actually to me it seems incredible that they did not immediately point out that they did not answer that way. From the demo video they were confronted with the changed results immediately after completing the survey. More bizarre is the statement in the article:

    No more than 22% of the manipulated answers were detected, and 92% of the study participants accepted the manipulated summary score as their own.

    Which appears to indicate that a least 14% accepted the manipulated answers as their own after detecting that they were manipulated. I'd also suggest that this study has a pretty significant bias because if you find someone with no short term memory who is somehow really fooled into believing that the opposite answers are their own, they may go along so as not to appear foolish i.e. they have not changed their mind but rather than admit to completely misreading the survey they just agree to save face.

  19. Re:Bad Ruling on Should California Have Banned Checking Smartphone Maps While Driving? · · Score: 1

    Oh yes, when people operate 1-2 tons of steel at moderate to high speeds in public, requiring some assurances of safe handling is the way to a police state.

    I've no problem with having such laws - my problem is with the suggestion that you can choose whether or not to enforce them. Making everyday life illegal and then letting the police decide who they want to prosecute is a sure way to end up in a police state.

  20. Re:1984 on Speeding Ticket Robots — Laws As Algorithms · · Score: 1

    And so does driving too slowly, you obviously have never driven in the UK so it's a no brainer.

    I have - the comparison of the A14 between Huntingdon and Cambridge before and after average speed cameras was the specific example I had in mind when writing the post. The effect of inconsistent speeds on UK roads is far more visible than in Canada where the traffic density is so much less. Drive down any busy UK motorway and you'll occasionally notice a back up of traffic near a busy merge (A1(M)/M62 junction used to frequently be a good one). Once you get past the junction the traffic speeds back up and you are left wondering what the delay was: it was slower vehicles merging and creating a backup. A similar effect is the back up behind lorries during busy periods. In fact I'm amazed that you could possible drive on UK motorways and NOT have noticed this effect!

  21. A better choice on S. Korea Says Cyber Attack From North Wiped 48,700 Machines · · Score: 1

    Personally I'd prefer no internet access to North Korea over a wiped computer. So how about we just disconnect them from the global internet instead?

  22. Not faster than light on European Researchers Propose Quantum Network Between Earth and ISS · · Score: 5, Insightful

    What the article fails to point out is that actually nothing is travelling faster than light. This is the fancy equivalent of shining a bright laser on the moon and moving it around so that it appears that the bright spot on the surface moves at a velocity in excess of c. There is no problem with this because no information is transmitted from one point on the moon to another point on the moon faster than c - the only information which is transmitted is from the person pointing the laser to the moon. In the same way no data is transmitted between the two people making the measurements because neither has any control over the outcome of their measurement.

  23. Re:1984 on Speeding Ticket Robots — Laws As Algorithms · · Score: 5, Interesting

    Yes but that system works spectacularly well - far better than radar traps - because you have to stick to the speed limit over long stretches of driving not at isolated points in the road. Also you do not have to worry about keeping your eye on the speedometer every second because if your speed creeps a little high you can easily compensate by driving a little slower. Finally the one effect I have noted on some really busy roads is that the flow of traffic is a lot smoother because now everyone is going just under the speed limit.

  24. Re:Bad Ruling on Should California Have Banned Checking Smartphone Maps While Driving? · · Score: 1

    Meh, laws don't necessarily have to be enforced, but they're convenient to have when you want to discourage particular behaviors.

    Sounds like an excellent recipe for a totalitarian police state. If it becomes acceptable to only enforce laws against people whose behaviour you don't like then whoever gets to define what appropriate behaviour is holds a great deal of power over that society.

  25. You don't vote for parents on Margaret Thatcher Dies At 87 · · Score: 1

    If you put a small toddler in a playpen with a kilo sack of sugar...

    Nice analogy but where it falls down is that toddlers don't get to vote for their parents. If toddlers did they might well vote for a parent who would give them a sack of sugar and let them get dangerously ill. In which case who's to blame: the parent the toddlers selected who did what they were voted in to do or the toddlers who wanted something which they should have known was bad for them?

    This is why democracy does not work. The only reason we use it is, to paraphrase Churchill, because every other type of government that has been tried so far turns out to be even worse.