qftme

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Phd student

	529 reputation	bio	website		visits	member for	2 years, 3 months
312 badges		location	London, United Kingdom		seen	Dec 3 '12 at 15:05

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Jun 9	comment	Why do we say that the earth moves around the sun? @Mark: Great video-link. :: chuckles ::
Jun 9	comment	Why do we say that the earth moves around the sun? @Lubosh: "In this sense, the heliocentric frame is more true." I don't agree with the phrasing of this statement - it is more convenient perhaps, but it is equally as 'true' as any other choice of reference frame. If the geocentric equations of motion correctly predict the motion of all celestial bodies then surely they too are 'true,' albeit a little more complicated.
Jun 8	comment	Given a radius and velocity calculate position of an aircraft banking to make a turn in three dimensional space In keeping with the comment by @Vintage, it would be helpful if you could explain why you have asked the question - I.e. the circumstances that let you to it and what you want an answer to achieve. As it stands it quite difficult to interpret and therefore answer.
Jun 6	comment	What does cross-track wind mean? @Georg: "You can English good enough.." Lol.
Jun 6	comment	Formulas for ball rolling in a bowl? Knowing a bit more about your background will help people to pitch answers at the right level. Are you familiar / comfortable with vector calculus? In what language are you attempting to program it in? How experienced with that language are you?
Jun 4	comment	Can heat be transfered via magnetic field in a vacuum? In light of the discussion ensuing from your answer I'll give you a (IMO) deserved +1. I'd like to see that calculation though.
May 27	comment	Is it outside science to figure out the precise string compactification of our universe? @Mitchell: The two comments you made in conversation with Peter Woit more than constitute an answer to the OP's question, and a good one at that. Transfer them over and I'll certainly give it +1 ;)
May 26	comment	How does non-commutativity lead to uncertainty? If I could nominate this answer for an award I would. Since there are none, +1 will have to suffice. Great job though.
May 24	comment	Graduate Physics Problems Books Take it you've thrown away all your old lecture notes, problem sheets and past papers then? They surely would be the best place to start.. I've given the question +1 all-the-same as I would also be interested in others' suggestions.
May 19	comment	Solar System Capture of Orphan Planets For the orbital period you mention, I'd imagine the effect on the Sun be very, very small indeed. Also, for a highly elliptical orbit, the magnitude of the effect must also depend on where on the ellipse this 'lonely' planet happened to be at the time; due to its varying angular velocity about the barycenter.
May 19	comment	Do the laws of physics evolve? @Dmckee: Regarding your first realated link - considering the fine structure constant in its capacity as the QED coupling, it scales logarithmically with energy; as a consequence of renomalization. Whilst its value at zero energy has been shown to be near-enough constant, for practical calculations at typical energies during the cosmic evolution it value has surely been diminishing as the Universe cools, no?
May 19	comment	How to invent a theory? @David: No, I'm afraid I must be dumb because I'm still not getting it. Why was this question closed please?
May 19	comment	Do the laws of physics evolve? Thanks @John. I did take a look but I'm always a bit sceptical of anything Smolin says. He has been known to come up with quite a few crack-pot theories over the years.
May 19	comment	Do the laws of physics evolve? B: Thanks for your answer. My intuition was that any change in the physical laws, whether we call that an evolution or not, would be a quasi-distrete change - perhaps corresponding to a change of state of the Universe as a whole (such as quark-gluon plasma => hadronized particle epoch.) I find it strange that the constants mentioned seem to change smoothly whereas the actual form of the equations seem to go from being applicable to non-applicable (or visa-versa) rather abruptly. Presumably a TOE should be able to reduce to the appropriate formalisms both before and after the change(?).
May 19	comment	Do the laws of physics evolve? To the anonomous down-voter: would you care to explain your reasoning?
May 19	comment	Do the laws of physics evolve? @HDE: Yes I was a little unsure about the phrasing there. Whould it be more correct to ask if the laws 'remain form-invariant thoughout the lifetime of the Universe?' If I can further improve the wording please suggest how and I will edit accordingly.
May 18	comment	Online QFT video lectures Stanford also have a number of freely available lecture courses. Susskind has posted courses on CLASSICAL MECHANICS QUANTUM MECHANICS, SPECIAL RELATIVITY, GENERAL RELATIVITY, COSMOLOGY, STATISTICAL MECHANICS, QUANTUM ENTANGLEMENT 1, QUANTUM ENTANGLEMENT 2, QUANTUM ENTANGLEMENT 3, BASIC PARTICLE PHYSICS, and THE STANDARD MODEL. Whilst none of these are specically QFT, you'll probably find th eStandard Model ones useful. newpackettech.com/Resources/Susskind/PHY30_2B/…
May 18	comment	Famous physicists' quotations @dmckee: "...complaints are part of why they are unsustainable." - I don't follow your reasoning. Furthermore, I really feel it would be to the detriment of the site if questions such as this are not permitted.
May 18	comment	Famous physicists' quotations @Ted Bunn: Oh well, I guess that's what happens when one quotes a quote that was already a quote etc. Chinese wispers effect.
May 18	comment	Famous physicists' quotations @ Nick: Well. Yes. I see your point, but that doesn't detract from it potentially becomming a very interesting thread. In it's defence, those other questions couldn't possibly have a universally prefered answer either; and they're not closed. I suppose it could have been phrased 'what's the best famous physicist quote, and why' but that would only differ in semantics.. ;)