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 Jul 15 comment real world applications of Mathematics which use functions with singularities, not just as a matter of mathematical taste but for conceptual reasons I agree with @Zev C: this should be a community wiki. Jul 13 awarded Civic Duty Jul 12 comment How to predict how much data to collect I was just getting my head around the details of what you wrote and I have a quick couple of questions, I hope you don't mind. 1/ In the order-of-magnitude estimate are you saying one can take $N_{\rm events}^{-1/2}=f$ and solve for $N_{\rm events}$? I can replicate your "decades" prediction in this way but - where you said "your measurement of a modulation will have an error of order $N_{\rm events}^{-1/2}$" shouldn't it have had a positive power? 2/ What was the motivation for you choice of $\hat B$? I'm afraid I just can't work out where this bit comes from.. Jul 12 accepted How to predict how much data to collect Jul 12 comment How to predict how much data to collect thank you so much for taking the time to answer, this is exactly what I was after, with more detail than I had expected. Thanks again. Jul 12 comment How to predict how much data to collect @Ted Bunn: Yes, in theory it would be possible for me to match the collected data (time-stamped detection events) with a known phase. In practice this may be a little more difficult as the phase is not quite constant and would need regular adjustments. Unfortunately the detector will be place in a somewhat hard-to-reach site so the practicalities of accessing it regularly may prevent me doing so. Regarding whether the events are Poisson distributed, I'm not overly familier with the science/stastistics of RVs, but having looked it up I get the feeling that the event rate here most probably is. Jul 11 revised How to predict how much data to collect clarify meaning without changing it Jul 11 asked How to predict how much data to collect Jul 1 comment Show that the electric field E in the system at rest is $E=\frac{Q}{4 \pi \epsilon_0 \sqrt{(x^2+y^2+z^2)^3}} (x,y,z)$ ..perhaps. Also, are you sure this shouldn't have had a special-relativity tag instead of GR? Jul 1 comment Whats the range of dimension exponents in the SI Units system? A combination of these two pages may be of some use: en.wikipedia.org/wiki/SI_prefix, and en.wikipedia.org/wiki/Dimensional_analysis Jun 30 comment maximum rotational speed @Marek's answer in @voix's linked-question seems to answer it for me. Good question all the same :-) Jun 30 comment how does dynamic casimir effect generate correlated photons Great question +1. I'm left wondering if measuring the flux of the photons produced could be used as a measure of some part of the vacuum energy spectrum? Jun 30 comment Does a static electric field and the conservation of momentum give rise to a relationship between $E$, $t$, and some path $s$? @yayu: indeed, particulry @Andrew's answer and the associated paper. Thanks Jun 30 comment Does a static electric field and the conservation of momentum give rise to a relationship between $E$, $t$, and some path $s$? Maybe I'm being stupid but surely if you could consider an object that has no net force acting on it, you would get 0 if you just took any loop integral around it: ∮pho⋅ds=0 What would one call the 'force field' be called though? Jun 30 comment On a bicycle, why does my back tyre wear so much more quickly than the front? @bubble: No, it was the incorrect physics that persuaded me. Jun 30 comment On a bicycle, why does my back tyre wear so much more quickly than the front? Sorry but there are a couple of incorrect assertions and even more spelling mistakes in this, hence a -1 I'm afraid. Jun 29 comment Collision between a rod and a bullet @Willie: I see what your saying, I hadn't thought of it that way but now you mention it I agree that two collisions could be possible. Jun 29 comment Collision between a rod and a bullet Interesting question. My 'hunch' would be that if the rod is indeed considered "rigid" (which is obviously not physical) the maximum number of collisions would be one. That said, I'm not sure I personally am capable of showing this using conservation of linear and angular momentum. I'll try a little back-of-an-envelope calculation later this afternoon.. Jun 28 accepted Hail stones in summer? Jun 28 comment What if the LHC doesn't see SUSY? Very interesting reading @Lawrence (+1.) @anna I just wondered if you had an opinion on 'proton-driven plasma wakefield accelerators'? See pg 18 on the slides of this recent talk for example: c-ad.bnl.gov/pac2011/proceedings/talks/tuobn5_talk.pdf Could this scheme ever be implemented in the main LHC tunnel in the years to come, and what energy lepton beams might this offer?