Recent content by Sunshine

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    Perturbations and harmonic oscillator

    nevermind... I found out where I went wrong.
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    Perturbations and harmonic oscillator

    Homework Statement In a diatomic molecule with atom masses m1 and m2, the atoms are bound by a potential V(r)=V_0\big[ \big(\frac{r_0}r\big)^{12} - 2\big(\frac{r_0}r\big)^{6}\big] where r is the distance between the atom centra, r0 is the equilibrium istance, and V0 is a constant depending...
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    Identical particles and degenrate energy levels

    Ok, didn't know that n could be 0. So the energy should be 2E_{000}+2E_{100}+E_{010}?
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    Identical particles and degenrate energy levels

    Homework Statement Five electrons (with mass m) whose interaction can be neglected, are in the same 3-dim harmonic oscillatorpotential V(x,y,z) = \frac k2 (x^2 + y^2 + z^2) What is the ground state energy? Homework Equations The Attempt at a Solution I have the energy for the...
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    Commutators in 2 dimensions

    You are right, the last integral becomes 0 as well -I accidentally made the assumption that a<0 istead of a>0 in Mathematica last time. So the conclusion is that the expectation value of both commutators is 0?
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    Commutators in 2 dimensions

    The professor took the question from an unknown book, typed it into word and emailed it. I don't think it's a typo, and I'd never dare to ask if it was. He wouldn't admit his mistake anyway ;) ok, second question is like the first one with a few differences: Now I have A = L_x B = z_x^2 And...
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    Commutators in 2 dimensions

    I'm confused because it seems too easy to count expectation value for 0. Especially when question 2 (out of 3 in the assignment) has a trivial expectation value too. Doing it for 3rd time just to make sure I'm not missing something. If it becomes zero again, I'll be almost certain that something...
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    Commutators in 2 dimensions

    yes, it is xp_x. So the expectation value is 0 as well?
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    Commutators in 2 dimensions

    Homework Statement Simplify the commutator [A,B] and give the expectation value of [A,B] in the ground state for an isotropic harmonic oscillator (mass m) that has the energy \hbar \omega /2 when A = xp_x B = y Homework Equations [AB,C] = A[B,C] + [A,C]B [p_i,x_j] =...
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    Studying life in other galaxies

    Hmm... I don't even know where to start, that's too advanced for me. I don't even recognize what system those 25 pc is from. If it's some american system then I don't know since I only use the metric system. Anyhow... it would be interesting of to get the answer of your question "Might there...
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    Studying life in other galaxies

    Ok, so there are no current searches for life outside milky way but we CAN study spectra from outside milky way with our current technology, and by that either say that earthlike life can't exist there, or that there is a possibility it could have evolved as on earth?
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    Studying life in other galaxies

    Dr.Brain, SETI are studying only the milky way, aren't they? Chronos, it doesn't need to be radio signatures specifically. As far as I know we can check the metallicity of a star outside the milky way, and hence tell if that star could have planets. If yes, could we then go further and base...
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    Studying life in other galaxies

    I've been reading about researches about life in our solar system, and the milky way, but I'm interested of knowing if these techniques can be used to study galaxies that are much farther away. So I'm mainly interested of the techniques used, and not towards what the results are heading ;)...
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    Studying life in other galaxies

    When we search for life in other galaxies we look for planets that have almost the same environment as earth, since it is believed to have the best opportunities for life to begin. Does anyone know some serious researches in this topic, or what techniques are used for this kind of researches...
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    Studying life in other galaxies

    But how would we detect signals sent from outer space, by living creatures?
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