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| bio | website | inspirehep.net/… |
|---|---|---|
| location | Duchy of Grand Fenwick | |
| age | 42 | |
| visits | member for | 2 years, 6 months |
| seen | 31 mins ago | |
| stats | profile views | 3,157 |
Experimental particle physicist. These days I'm doing neutrinos.
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Sep 11 |
revised |
How to calculate calorie expidenture from lifting a weight? edited tags |
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Sep 11 |
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How to calculate calorie expidenture from lifting a weight? Closely related: Why does holding something up cost energy while no work is being done?. Also various other biophysics questions may have some relevance. |
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Sep 11 |
awarded | Synonymizer |
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Sep 10 |
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Why do electron-positron pair annihilate upon contact? I'm not really happy with this answer, because ground state hydrogen atoms have a non-zero expectation for the electron to be inside the proton (it is an s-wave after all), what prevents the reaction $e + p \to n + \nu$ is insufficient energy. |
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Sep 10 |
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A question related to Gauss's Law Welcome to Physics.SE! Policy here calls for not answering homework problems as such. If you can distil this question down to the principle where you are stuck we may be able to help. BTW--mmc's comment is aimed at helping you with that distillation, to that I'll add "Have you noticed the symmetry present in the problem, and do you know how to make it work for you?". |
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Sep 10 |
revised |
A question related to Gauss's Law deleted 57 characters in body |
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Sep 10 |
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Remnant of a supernova I've opened a meta-discussion on the appropriateness of such cross-posting. Everyone is encouraged to stop by and put in their two cents. |
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Sep 10 |
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Remnant of a supernova Cross-posted to Astronomy.SE: astronomy.stackexchange.com/q/1194/211 |
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Sep 10 |
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Remnant of a supernova Much of the English in this question is unclear, could you try to be more explicit? |
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Sep 10 |
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Acceleration vector - deceleration vs direction Mind you, you can make the distinction in whatever frame you chose and it sometimes makes communication easier, just be aware that the distinction has no physical significance divorced from your choice of reference frame. |
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Sep 10 |
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Acceleration vector - deceleration vs direction added 8 characters in body |
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Sep 10 |
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Acceleration vector - deceleration vs direction @Jonathan: There is no (can not be a) difference between accelerations that are parallel, anti-parallel, or orthogonal to the velocity because the there is no unique frame in which to measure velocity (this is not, BTW something new, Galileo relied on this principle). Thus any distinction you make between "acceleration" and "deceleration" is purely a linguistic one based on the frame you have chosen to measure the velocity in. |
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Sep 9 |
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Acceleration vector - deceleration vs direction This is a very fundamental question that I hear a lot from beginning students, and I don't really know where ti fits into our convention on not answering basic exercises. Input from the commentariet would be appreciated. |
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Sep 9 |
answered | Acceleration vector - deceleration vs direction |
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Sep 9 |
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Acceleration vector - deceleration vs direction added 10 characters in body |
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Sep 9 |
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Compressing a fluid with arbitrarily large force in an infinitely strong chamber The term you are looking for is "degenerate matter". Specifically matter supported by a degenerate Fermi gas of electrons (the stuff of white dwarf stars) first and then matter supported by a degenerate Fermi gas of neutrons (the stuff of neutron stars, also called "neutronium"). |
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Sep 8 |
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simple test/measurement to quantify water opacity Sometime you find these kinds of measurements expressed in terms of the "attenuation length" $l_a = 1/\mu$, and it is often necessary to express these values as a function of wavelength or frequency: $l_a = l_a(\lambda)$. |
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Sep 8 |
revised |
How do Leptons arise from Lambda decay? format the quote |
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Sep 8 |
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How do Leptons arise from Lambda decay? The big hint here is "Use [...] the boson model of the weak nuclear interaction". Ask yourself what is special about the weak interaction as compared to the strong interaction? |
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Sep 8 |
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I found it strange in case of an egg omlette You've discovered organic chemistry! |
