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imatfaal

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Everything posted by imatfaal

  1. ! Moderator Note 10 Sorry Petrushka Googol you have failed the turing test. 20 Please use another forum for testing Petrushka Googol 2.0 30 You have been warned both officially, in modnotes, and by members/forum experts. 40 No change of behaviour was noted 50 You have now been placed in the mod-queue. 60 Your posts/new threads will only appear if a moderator confirms the post 70 End
  2. I work with people who spend the best part of their lives in the deep ocean - mariners who will be on constant watch for maritime debris in some parts of the world, small boats in others, pirates tragically in more seas than is acceptable, and even icebergs in the North Atlantic; they have some pretty good tales to tell but none of these USOs you are saying are so common
  3. site:scienceforums.net imatfaal sheldrake that's how I find old threads - use google
  4. Pumping high intensity light into a crystal structure sounds a bit laser-ish - are there connexions?
  5. Sure monopoles exist - electric charges are monopoles of a sort; the neat trick that will earn you a nobel prize is to find a magnetic monopole. I haven't read Dirac in any detail - but was he an advocate or did he merely state that if magnetic monopoles exists then electric charge must be quantised. That statement is very different than the other way around or than stating a necessary and sufficient etc. Charge is quantised - but that does not prove magnetic monopoles exists; if we knew of magnetic monopoles and Dirac was right it would show that charge must be quantised - but not vice versa. Professor Paul Davies is a tenured Professor at a great University - that does not mean that when he steps away from his comfort zone, into bio-chemistry of life (search Paul Davies Arsenic), epistemology/theology (search Paul Davies templeton prize), and into pop-science that he can be taken literally and as authority. Perhaps the fact that Hoyle was his post-doc supervisor might colour our picture of him - brilliant but a bit loopy WE have strung plastic sheeting around various parts of LHCb in the hope of finding magnetic monopoles so the search continues - and no this is not entirely a joke
  6. Anyone here gonna be voting in the Primaries (I follow US politics pretty faithfully for a brit - but I am still a bit hazy on who gets to vote in the state primaries) I can see from geographical labels that iNow might/does get votes on Super-Tuesday, as might/does Phi, yDoaps is way into May, which by then, might be a one-horse race, and I forget if Overtone has every mentioned a home state. Everyone else seems to be an interested foreign observer (maybe that comment should be part of the What is Wrong with America thread) As far as I can tell Texas is an open-primary (an registered voter can vote in both Dem and Rep) and Colorado is closed caucus (only reg party members can vote in their respective party primary). I would not dream of asking who people will vote for - but I am curious if you guys will actually vote. But please feel free to say f off none of your business I really do not know who I would vote for at present - Sanders is politically very close to me but I worry that he is unelectable whereas Clinton is almost as far as a Democrat can be from me but I worry that she might be unelectable. Hmm - really dilemma; Bernie's avowed left-wing policies which will mobilise huge power blocs against him or Hillary's idiopathic antipathy which is widespread across America. On the Republican side - again I would be torn between voting for one of the complete nutters to firstly enjoy the entire unedifying spectacle of the Grand Old Party eating itself and secondly to clear the way for a democratic nominee in general e, or trying to vote for one of the more sensible (I guess only Kasich) so that the election could be a bit more grown up, or maybe finally bush to get him and his backers to carry on pissing away money (84 million so far acc wiki)
  7. Gees Your cod-psychoanalysing is embarrassing to you and insulting to me - please stop.
  8. http://www.mathpages.com/home/kmath290/kmath290.htm Math pages is often better for this than wikipedia
  9. I have no idea - but it is a neat thought. I will await with interest what people say; whilst trying to get my head around wavelengths etc and whether it is even possible. BTW the idea of the gravitational wave imparting energy would of course "pay back" the energy "borrowed" to create the particle pair (like the shrinking of the black hole "pays it back"). In my naive notion the particle pair is so close and the time so short (it is related to the change in energy by plancks constant which is very very small) that no gross macrodistortion of space could interfere. But then some reports of the LIGO results say that the merging black holes emitted gravitational waves carrying away the mass energy equivalent of 3 solar masses in a fraction of a second - thas pretty extreme!
  10. Thanks - I hadn't seen him talk before. Damn but he is articulate, charismatic, and persuasive - the old white dude wasn't bad either
  11. Firstly - the effect only applies to particles which are smaller enough to be changed by radiative pressure but not so small that the radiative pressure will blow them away completely (which is what you are seeing (in part) with the dust being cleared). It is a very narrow range of particles. Secondly - you have to look from the frame which stationary with respect to the star. And yes from the frame of the star the radiation re-emitted by the particle is more energetic and carries away more momentum in the direction of travel than in the reverse direction. Remember energy and momentum are related to frequency The best paper I can see to read about it is the heuristic description in Burns, Lamy,and Soter 1979 "Radiation on Small Particles in the Solar System" which is findable by google but I am not going to post a link cos not sure about the validity of the site I found it on
  12. I am pretty sure someone brought up Nirvana (which is a mystical experience in terms of super sensory perception) and unitive ascetic practices before then
  13. from a quick google Poynting Robertson effect is due to asymmetries involving very small particles of dust in orbit about a star. Very simplistically - From the POV of the particle the sunlight hits it a tiny bit more on its leading side than its trailing side (it is running into the rain) thus there is a tiny loss of angular momentum as the inequality of pressure from radiation provides a net torque against its rotational motion around the star. From the POV of the star the light hits the particle at exactly 90 degrees BUT the re-emission of thermal radiation is stronger in the direction of travel than the reverse and thus the imbalance of photons emitted can be seen as lowering the angular momentum WRTo the star
  14. Not sure I follow that - but in checking my approach to reply I noticed that the received model for density of the earth has g constant for about the first 2000km and then rising to max at r=3500km with g =10.68m/s2. So any objection would be theoretically correct for the wrong sort of planet - but completely moot for earth
  15. Surely the lithostatic pressure should be the integral and not the simple multiplication - g varies with depth and over roughly 1/6 of the earth's radius will vary enough that it must be taken into account.
  16. But you are constantly challenging GR and asking whether experiments have been undertaken to check remote and unlikely areas. And the "reasons" - is linked to a thread which gives no reasons just a misunderstanding of the concept of inertial frames. Again - what seasonal / daily variations do you expect?
  17. Just to be clear I am considered stupidly liberal in NWE and hate gun ownership and am pro a women's right to chose...but Roe v Wade (which I presume you meant) was a decision made in expediency with little legal backing and absolutely no real constitutional strength (the power of the judgment is founded in a previous judgment of the same court and the long term acquiescence of the other two wings of government) - even though I think it was the right thing to do. The Second Amendment followed the spirit and the letter of the protocols to amend the constitution - even though I think it is bollox. With respect, and from a legal standpoint - one can quite clearly be seen as activist judges overstepping the mark and the other is the act of a properly constituted legislature working in hand with the individual states. The import of the two matters may be seen at a similar level - but from the legal view there is a huge gulf. And regarding your jibe about legal scholars - at least one of the people making the claims in this Republican Primary season is an former clerk to William Rehnquist (who sat on the case itself) when he was Chief Justice of the USA - another is a JD.
  18. The press release http://www.ligo.org/news/media-advisory.php
  19. http://www.amayamoro.com/ She seems very well respected for someone still on the track - and has a lovely looking website combined with right-on political views
  20. It is a chapter in a book (you will very rarely see a peer reviewed article of that length) Planets, Stars and Stellar Systems. Volume 3: Solar and Stellar Planetary Systems (Oswalt, T. D., French, L. M., Kalas, P., eds), ISBN 978-94-007-5605-2. Springer Science Firstly it carries the imprimatur of the Editors of the book - and if you want to read through it (I haven't) you might well find that sections of the chapter are lifted straight from Articles with stringent peer review. You might also find in the chapter itself or in introduction or acknowledgements the names of a colleague or two who have read the chapter ( ie I thank so and so for her help and corrections during the writing process - however all errors and omissions which remain are strictly my fault) Secondly - if the publishers are reputable then it is unlikely that the editors of the series or the general editor would allow arrant nonsense FYG most people update their arxiv copies when they are peer-reviewed to show the name / date of the paper publication
  21. ! Moderator Note moved to homework help
  22. I will take a tiniest tiniest bit of credit for some that. I filled in a survey many years ago as an early user of Wolfram Alpha and my big complaint was that whilst it understood pi it didnt parse any physical constants - my two bugbears were G and h - I got a lovely chatty message back saying that so many respondents had asked for that implementation and it was in the works. My other grumble was that if you used a major European city in a query it always defaulted to the American version - and it still does! Ask about Westminster and it asked you Westminster Colorado (been there Phi?) or Westminster California - and I every time I want to scream at the screen
  23. FFS - you lecture us on complex physics and cannot even do sums! You put this [latex] \rho_c=\frac{3.H^2}{8.\pi.G} [/latex] with H as 2.3 x10^4 (more on this later) - the other values are well known. But you got 3.2 x10^-1 With your figures the answer is from Wolfram Alpha - is 9.5 x 10^17 - You are about a billion billion time out. I made this about as plain as I could with an order of magnitude approximation and you still have the brass neck to claim you are correct. What's worse is your formulation of the sum was completely wrong because you didnt have the physics knowhow to realise you were using a completely erroneous figure of H - which is why even the "correct" mathematical answer is way way out. ===== Moving on to the physics - your figure of H is taken from a table which clearly says it is the ratio of H to H0; that is to say the ratio of the H then to the H now. That is why it is unitless - it is a ratio - it is also why the current figure is 1. ===== Have a bit of humility and learn some basic maths and physics before attempting to lecture the members on the finer points of astrophysics @Strange I think you need to have Hubble's parameter in its base SI form - ie second^-1 to give it as a density; but not entirely sure how well Wolfie A handles mad unit transformations. edit It turns out brilliantly - I hadn't realised you could do what you did The critical density is currently calculated at about 10^-26 kg/m3 - an increase of H by a factor of 23,000 would lead to an increase in the critical density of about 500 million o/t Chapeau to Wolfram Alpha for its amazing ability with units
  24. Capayan - I presume you would be happy to take a 5-7% wage drop? Or maybe you already receive 5-7% less than your male counterparts. Any significant variation is unacceptable in a modern polity. Cos that's the short/most equal end of the statistics - and it is still disgraceful. Statistical measures will always be argued - because there is no correct answer. But if by some measures you have a 22-23% disparity and by others you have a 5-7% disparity it is clear there are many confounding factors making a simple metric impossible - however; it is also clear you have a right problem on your hands
  25. OK the question I want to have answered is how will the GOP jump A. Get behind front runner Trump and blow the other candidates away B. Focus on one of the three potential other real candidates (rubio/cruz/bush) and pressurize the other two and the also rans to get out quick. Thus allowing a single establishment candidate to use endorsements, huge funds, the frightening large power base, and friendly media to finally overhaul Trump C. Sit with their thumbs up their arses whilst a destructive and bile-drenched internecine battle makes the whole lot of them look - amazingly - worse than they already appear Nate is giving trump about 10% lead in SC (the average of his predictions against the average of the next highest runner) - and reckons that this corresponds to a 55% chance of a Trump win. Second would be a toss up between Rubio/Cruz. Bush would stick at 10-12% Asterisk - in case any readers cannot go online *Marco Rubio converted his Senate campaign committee into his presidential campaign, starting his run with several million in cash. That money is not included here
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