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    Tradition of physics wagers : Higgs Boson

    Hi Justin, There are many many other wagers in physics over history. We're working on a feature about it in symmetry magazine already so we'll have a bunch to tell you about coming up. They include the SLAC National Accelerator Lab bet book, a bunch of bets at Caltech, and various others...
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    Overturning GR contest

    I think they're still doing the analysis for GP-B, actually. I don't have any inside information at the moment, sorry.
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    Overturning GR contest

    You might be interested in the contest that ran at the SLAC Summer Institute this year that asked: "What will be the first evidence to demonstrate that Einstein's theory of General Relativity (GR) must be revised, and when will that be found?" The...
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    October issue of symmetry out today

    New issue of" is about the Snowmass meeting to work toward designing the International Linear Collider. Other stories:": An experiment with polarized electrons probed the strength and asymmetry...
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    Experimental/theoretical quantum optics?

    If you want to work in quantum optics, you don't NEED any of these in any real sense depending on exactly what you do. However, you would be well-advised to get a grounding in QFT and techniques in mathematical physics. That said, I would advise you to take as much theory as you can handle...
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    Gravitational field, g

    As Tom points out, the value is local. But it depends on more than just your radius because there are local effects that distort the gravitational field. Indeed, detecting these distortions is one goal for people looking for deposits of minerals, ore, oil, etc. The varying can be quite...
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    Classical Mechanics (Lagrangian)

    You don't seem to have explicitly factored in that the slope is changing in time. (There is no alpha dependence in your equations.) What this also means is that the velocity of the particle is not as simple as it seems, and is not along the inclined plane in the lab reference frame anyway. For...
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    Conservative Systems

    Although not conserved separately, I am sure you realize. Where does this equation come from? It's not a wave equation in the usual sense (unless you mean that x is a time variable). It certainly doesn't have anything to do with a hydrogen atom. Or am I misinterpreting and is supposed to be...
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    Solution needed 4 a very good problem!

    Is this a math olympiad problem by any chance?
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    Randall Sundrum Model

    I think we need more information about the model to say anything sensible. What is the reference for this? Giving that metric by itself doesn't indicate a solution to the hierarchy problem in any meaningful way without more information.
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    Conservative Systems

    It's not clear exactly what you mean by this but if you are just looking at a (non-interacting) hydrogen atom, then there is a well-defined Hamiltonian which gives a conserved energy. If you are referring to something to do with Heisenberg's uncertainty principle, then it might get subtle...
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    Original Data from Bell's Experiment

    I guess you realize that Bell didn't do the experiments himself. The landmark experiment was done by Alain Aspect and collaborators in 1981. Here is the paper you should read to start with: A. Aspect et al., Experimental Tests of Realistic Local Theories via Bell's Theorem, Phys. Rev...
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    How to quantize a system in cubic well

    It will indeed separate so then you just have to be careful about counting modes, etc. and degeneracies. If it is truly cubic (the lengths of each side are the same), then there there are 3 degenerate modes for the first excited state.
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    Quantum Superposition

    Are you really interested in whether they can form a superposition or whether they can form a bound state? Matter and antimatter can form bound states, for example. See this article which talks about positronium. It's very short lived but can exist. It's not really clear from your question why...
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    Vector Space & Vector Subspaces

    You are definitely on the right track but you have to be more explicit about the statement "a vector that satisfies the conditions of a subspace of U and W, (the intersection of U and W) then it is part of the U u W" - you need to give the details there.
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    4-momentum problem

    It might help to know what the question actually asks.
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    Circular motion of a particle

    I interpreted the question to mean that you only consider the average over half a circle and that is why the semicircular path is mentioned and the "average" acceleration is asked for.
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    Circular motion of a particle

    This problem is a little more complex the way I read it. I assume is asking for the average vector acceleration not the average magnitude of the acceleration vector. So what you have to do is work out what the acceleration is at any point on the semi-circular path (you should know an...
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    Magnetic energy? Perhaps

    Thanks, Evo. I'm not sure how I came to be world famous... The new member date, etc. are just because I've been out of action in the forums for a couple of years but came back to chat with you all again. (I couldn't remember all my old login info, etc. so started afresh.)
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    A proof of RH using quantum physics

    Precisely for the reasons I said above: It's not a proof! People have made the observation you think you are making even more concretely but they all acknowledge that it is not a proof of anything. So what we are saying is that even if you turn this into a coherent statement, it is something...
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    A proof of RH using quantum physics

    I'll let Matt continue to point out the circularity of the argument being presented here adn tackle it from a technical viewpoint but will add one other little piece of information to the discussion, just to demonstrate the futility of this in a completely different way. Supposing this were a...
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    Boolean algebra

    You can just expand out both expressions and see they are the same. You will need to use de Morgan's laws to turn the complement of a product into a sum of complements, however. That is the only tricky part.
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    Particle dropped in hole through the earth

    Here is just a hint that might or might not get you started. Have you ever solved a problem that asks you when the minute hand and second hand on a clock are perfectly aligned? This problem is equivalent to that.
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    Particle dropped in hole through the earth

    This might seem mysterious at first but it is key to solving the problem. To understand how you get this formula, you need to use a theorem proven by Newton that says in a spherically symmetric mass distribution, the gravitational force is determined solely by the matter contained inside a...
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    Permutation and combination in maths

    There could be some confusion about what the question actually asks. If you stated the question exactly as given that might help. As I understand it, you are ask to create a seven-digit number where each digit comes from a set of five choices, and there must be at least two different digits...
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    Basic Physics ?

    Here is another hint: When will the two trains meet each other?
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    How heavy would you be on neuron star

    Here are the steps you need to get to the answer... Your weight is your mass times the gravitational field strength. W=mg. g depends on the mass and radius of the object like this: g = \frac{GM}{r^2} So for a particular person, their weight will scale as the mass of the planet/star and...
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    Double-Slit Question - PLEASE HELP

    You might have trouble doing this with natural light. If you use a broad-spectrum source, like natural light, all the different frequencies will have overlapping interference patterns and you won't clearly be able to distinguish between them. If you just try to filter it with a sufficiently...
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    Did I do something wrong?

    Did you check that your calculator was set to the appropriate degrees/radians setting?
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    Basic Physics ?

    There are two ways to solve this problem. One is to actually work out the full path of the bird between the trains. You end up calculating the limit of an infinite sum. It's do-able but messy. The other is to think creatively as to how to solve the problem using the information given in a...