Recent content by azoroth134

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    Graduate How to get position operator in momentum space?

    I already did that, I just don't know what to do after that, I don't have any derivative to perform on x or p
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    Graduate How to get position operator in momentum space?

    Hi, I wish to get position operator in momentum space using Fourier transformation, if I simply start from here, $$ <x>=\int_{-\infty}^{\infty} dx \Psi^* x \Psi $$ I could do the same with the momentum operator, because I had a derivative acting on |psi there, but in this case, How may I get...
    • azoroth134
    • Thread
    • Momentum Momentum space Operator Position Position operator Space
    • Replies: 5
    • Forum: Quantum Physics
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    Deriving the Stefan-Boltzman law and integration tricks

    problem solved, thanks a lot
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    Deriving the Stefan-Boltzman law and integration tricks

    Ah great, thank you very much, I almost got it on the track now, this is $$ \int_{0}^{\infty} x^3 e^{-(n+1)x} dx = 6 (n+1)^{-4}$$ can you just tell me a little about how to evaluate the summation of $$\sum \frac{1}{(n+1)^4}$$ though, I think I forgot this evaluation. thanks in advance
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    Deriving the Stefan-Boltzman law and integration tricks

    Homework Statement HI people, I was trying to derive the stefan-Boltzmann law from the planc's formula, I kind of got stuck with an integral Homework Equations $$ \int_{0}^{\infty} \frac{x^3}{e^x -1} dx $$ The Attempt at a Solution I tried simplifying it with $$ \int_{0}^{\infty} x^3...