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imatfaal

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Everything posted by imatfaal

  1. I haven't followed this thread but it is clear that you maths is awry [latex] \rho_c=\frac{3.H^2}{8.\pi.G} [/latex] As given by you (and not by Mordred) the top of the division is larger than one. G is much much smaller than one - but is on the bottom so its effect is to increase size of answer; there is no way it is going to be as small as you suggest. Just look at the powers of ten [latex] \rho_c \approx \frac{10^1.10^4.10^4}{10^1.10^1.10^{-11}} \approx \frac{10^9}{10^{-9}} \approx 10^{18} [/latex] You really need to understand these equations before you go plugging numbers in to make a point - but even before that you need to have a feeling from the maths of whereabouts your answers must lie. Once you have the maths right you can first - before plugging in numbers and contradicting people - make sure that you understand whether you are using the correct physical constant, it is in the correct form, and that it is in the right units - ie please don't just rerun the equation and say here is an even more unlikely answer; find out why you are getting odd answers first* *Take a look at the title row of Mordred's table
  2. To give Rob his due; Hyperphysics - whilst being no where near the standard of a peer reviewed journal - is a good resource for basic physics (at school level) and run by a practising physics academic (Dr Rod Nave) under the auspices of Georgia State Uni. The data given are referenced as from a pretty standard undergrad/postgrad physics text on the subject. Dr Nave hints at the lack of evidence provided, the unreliability of any firm conclusions (which Rob has missed entirely - and Rob has even managed to choose the less than likely choice), and uses this as a passing lesson in the need for better data sets and invites comments. We must be careful to remain sceptics in these matter - and not become automatically-gainsaying cynics.
  3. Rob - you might want to do a little quantitative analysis on that. The mass of the neutrino is not well defined (most calcs you find for its momentum will assume the mass is zero) - but it is a fraction of an electron volt 1 ev/c^2 is 5e-37 kg 1 amu is 1.66e-27 kg Cl is about 37 amu - you have 11 or so orders of magnitude difference in mass Even in an old fashioned momentum conservation equation you will get a max velocity change of about 10e-3 m/s - a millimetre per second. Noticeable if you are looking in advance but not otherwise
  4. Don't be ridiculous. A rest frame was chosen - but the clocks were in relative motion with respect to the arbitrarily chosen rest frame and with respect to each other; that's the whole point. AND BAD FORM ... That phrase does not appear on your referenced site as far as I can tell. The phrase "Considering the Hafele–Keating experiment in a frame of reference at rest with respect to the center of the earth..." does appear. You have changed the import of the phrase - in order, it seems, to make it support your case. If you do this you CANNOT put quotes around it. This would be severely frowned upon in every academic discipline
  5. au, miles and km - all in the same equation. You gotta show some love to SI and stop abusing units. How you got the right answer God only knows - but I got 5.085*10^8 as well
  6. Do you actually know the solutions to Sagnac for example? you have a circle radius r - with angular velocity w you can calculate Delta t as follows That seems to me as a very non-relativistic calc. And BTW can you drop using the term classical as an opposite to relativistic - classical physics tends to be used as that which does not include Quantum Mechanics not that which does not include Einstein's Relativity
  7. Your reasons - until spelled out and preferably quantified are a chocolate teapot; ie not a lot of use. Perhaps think if there are any already pre-existing data which could double check your ideas - what about the signals from space probes that are out of earth's orbit The standard time dilation is a result of the schwartzchild solution to the Einstein Field Equations; this is the vacuum solution around a non-spinning black hole - but is close enough to use. Frame dragging is a result of the Kerr Solution to the Einstein Field Equations; this is the vacuum solution around a spinning black hole. To include the angular momentum AND the linear momentum seems an entirely more complex request as you have to insert in your idea the idea of an observer/test particle not only removed from the black hole (or whatever) but also in relative linear motion to the black hole; how do you do that - if I have read correctly parties agree on the ang mom and mass of objects but there are frames you can chose which negate linear momentum (the local frame) etc. And even saying that - which I am fully prepared to be quite wrong about - solutions to the EFE are very difficult to come by anyway. Even saying all that - you solutions will include G - Newton's Constant which is only known to 4 decimal places (a relative uncertainty of 4.7 *10^-5) This is technically the nicest way to work out the difference for a schwartzchild solution by the way - the r_s terms all have limited accuracy due to G as a component [latex]\frac{f_1}{f_2}= \sqrt{\frac{1-r_s/r_2-\frac{(v_2/c)^2}{1-r_s/r_2}-(\frac{r_2 \omega_2}{c})^2}{1-r_s/r_1-\frac{(v_1/c)^2}{1-r_s/r_1}-(\frac{r_1 \omega_1}{c})^2}}[/latex] What seasonal variations do you expect - are you thinking the difference in orbital velocity at perigee and apogee; cos that just aint gonna be discernable. And the pole v equator thing doesn't show up the variation we might like because the change in velocity is confounded by the change in gravitational potential. You could easily stick the figures from the net in the equation above to see what happens - I think the time dilation is equal to about one part in a thousand billion. However I think a certain persons clocks are down to about one part in a million billion so maybe a pair of super accurate clocks will see a significant difference. Theoretically - for a fluid surface of a homogeneous rotating planet then there will be zero difference as the sea level will be a surface of equipotential (otherwise it would change to a lower energy state). But earth is not homogeneous so maybe you could work out a difference - not sure why you would want to though
  8. i'll try again Nothing is time dilated in its own frame. Things are only dilated in other frames. The clock is NOT running fast or slow in its own frame - it is only dilated when viewed from my frame which is at a different gravitational potential and in relative motion.
  9. Nothing is dilated in its own frame. It is other frames in relative motion that are dilated or length contracted when compared to the local frame - the local frame is always normal to the observer within the local frame (ie the definition of local)
  10. ! Moderator Note you have blown your chance. too many insults by far. this thread is locked. Dan98 It is unedifying to see one who claims to be so young and so gifted being quite such a bigot. Your preconceptions have blinded you to the chance that you may be mistaken; I hope you are so talented that this will not hold you back in your career but worry that any innate ability will be squandered through a lack of critical self-analysis If you wish to continue with your participation in discussion at these fora you will have to learn to accept the reality of debate (the possibility that others may have more knowledge on a subject) and how to participate without descending to pejorative remarks quite so quickly. Do not raise this particular topic again - but please do engage in the maths or other fora. Do not respond to this moderation - report this post if you feel it is unfair
  11. ! Moderator Note thread locked and email address removed
  12. Paramilitary police on the streets, highest non warfare security status, requests from the government for the public not to criticise the police, posting pictures of cats when deprived of civil liberties ... panic Anyway this is not politics. You clearly do not understand the chemistry, I am pretty sure that you don't understand the law; a few years ago an amateur chemist who ends up with sapeur pompier having to put out their kitchen would get a slap on the wrist - now they might well get the book thrown at them.
  13. ! Moderator Note moved to Speculations
  14. ! Moderator Note Thread Locked. You have a thread in speculation.
  15. Rotational frame dragging is hard to detect - one part in tens/hundreds of billions; linear frame dragging will be much much harder. We do have satellites on the other side of the sun - I think for heliological surveys - but not sure if any would be equipped (or could be equipped) with the sort of accuracy of clock that would be required.
  16. [pedantry] programmes [/pedantry] A missing letter can be replaced with an apostrophe - wouldn't have it any other way - but an abbreviation is normally shown with a full stop. The apostrophe has its uses - it's normally used to designate possession except when it isn't. And the quote system works fine for me. Press the button marked "Quote". If you are still having problems could you explain what you are doing in the Suggestions Forum so that we can work towards a solution
  17. Clarinets do E3 to C7 - not sure why you would bother with your Soprillo at B3 to E6. Saxes tend to be louder - but clarinets can (almost uniquely for woodwind) perform from ppp to fff. Is this not filling a gap that doesn't really exist?
  18. A type 2 error is the mistake of not rejecting a false null hypothesis. The null hypothesis is that the movement is caused by air current and vibrations etc. We would reject this if we were able to show that this explanation is unlikely. We would be wrong in not rejecting the null (a type 2) if we had evidence that should have persuaded us of another hypothesis but instead we kept the null. Every proper experimental refinement improves the power and significance of the test - but on the whole something that rules out other potential causes of movement of the psiwheel would rule out type 1 errors not type 2
  19. You aren't the first and won't be the last to be let down by the simple units conversion after lots of complex maths - it's why we like SI and why I use Google and Wolfram Alpha to check any conversions I do no matter how trivially easy they appear on the face
  20. Surely with position momentum entangled particles (spdc photons) if you measure the momentum to whatever accuracy you want of A you know the momentum to that accuracy of particle B - it is the position of particle B that is undefined within uncertainty parameters
  21. To properly understand this is difficult - this is not taught in any depth until a fair distance through a physics degree . To get a rough view - try hyperphysics. Or Search on John Baez - his notes are a bit easier going and less mathy. One problem is that gravity isn't amenable to a simple logical explanation - Newton might well have been one of the brightest people who ever lived; his explanation was simplish, not very logical, and had limits of applicability (which your questions are beyond). Einstein could also lay claim to that honour - and his explanation has the same failings and is MUCH MUCH harder to understand.
  22. First you want to isolate - I would do it like this. and leave for an hour before attempting anything Second I would randomise attempts - ie coin toss heads try and move it Third I would remove possibility of regular movement confounding test - ie roughly for every minute spent trying to move it spend one minute (coin toss tails) doing nothing Fourth - I would not be able to check on the movements of the psiwheel - curtain or board in front of it Fifth - I would not check the results myself. Slight more involved a. Set up camera on constant record of psiwheel - should also be able to see clock b. you set your watch to same as clock c. at 1500hrs you toss a coin, note H (heads) or T (tails) result against 1500, and either try to move or dont dependant on coin toss d. at 1501hrs you repeat e. keep this up as long as you can be bothered f. a friend (who has no access to your notes and is previously uninvolved) looks at video only and makes a note against 1500 for whether there was a noticeable sustained movement (Y) or not (N) , and for 1501, and for 1502, and for .... as long as he can be bothered Sixth - you find a nice experimentalist who will know the best way of determining statistically whether you have significant results - you give him ONLY the two lists of times and notes and ask if there is a statistically significant correlation between H / T on your notes and Y / N on your friends
  23. Before Iowa I was being told that losing would be such a bandwagon-stopping sobering effect for Trump that even a good NH would mean his campaign would be faltering before reaching the big ones in March. however it now seems that Hillary is the one with that effect - and she doesn't stand an ice-cubes chance of winning NH so it is quite a wait till Nevada (which she is likely to win) and SC which she is at present strong strong favourite
  24. Dan - get yourself a better guide to General Relativity. That is a post by a school boy - it is great for a school boy - but you can do so much better than that. If your maths is up to it look up Sean Carrol's notes - they are superb; and if your maths is not upto that standard then you will struggle to get a really good handle on what is at its foundation a mathematical and geometrical idea.
  25. http://www.wolframalpha.com/input/?i=.875arc+seconds+in+radians =4.242e-6 radians http://www.wolframalpha.com/input/?i=(2(6.67e-11*1.989e30)%2F(3e8%5E2*6.96e8) =4.236e-6 radians The old Newtonian calc (this is an approximation but damned close) looks to be misfunctioning just as it is meant to what calculation were you using?
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