Recent content by Dansuer

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    Peskin complex scalar field current

    Homework Statement i'm trying to calculate the charge operator for a complex scalar field. I've got the overal problem right but I'm confused about this: On page 18 of Peskin, it is written that the conserved current of a complex scalar field, associated with the transformation ##\phi...
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    Multiple Integral Challenge Question, no solution in guide

    I'm not familiar with Matlab, but didn't you forgot the exponential in the definition of z ?
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    Two varibale function. Continuity, derivability and differentiability

    Oh i see what's the problem. Thanks a lot for the help :biggrin:
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    Two varibale function. Continuity, derivability and differentiability

    Homework Statement Discuss the continuity, derivability and differentiability of the function f(x,y) = \frac{x^3}{x^2+y^2} if (x,y)≠(0,0) and 0 otherwise Homework Equations if f is differentiable then ∇f.v=\frac{∂f}{∂v} if f has both continuous partial derivative in a neighbourhood of x_0...
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    Particle on a Ring: Finding Mean Value of Sin(phi)

    I'll look at the action of the operator on a general eigenstate Sin\phi \left| n \right\rangle in the \phi basis \frac{e^{i\phi}-e^{-i\phi}}{2i} e^{in\phi} = \frac{e^{i(n+1)\phi}-e^{i(n-1)\phi}}{2i} Sin\phi \left| n \right\rangle...
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    Particle on a Ring: Finding Mean Value of Sin(phi)

    The ϕ operator in the ϕ becomes the identity operator. With this in mind, i write Sin\phi = \frac{e^{i\phi}-e^{-i\phi}}{2i} i'm not really sure where to go from here. What is e^{i\phi}\left|1\right\rangle ?
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    Particle on a Ring: Finding Mean Value of Sin(phi)

    Homework Statement Consider a particle on a ring with radius R in a plane. The Hamiltonian is H_0 = -\frac{\hbar^2}{2mR^2}\frac{d^2}{d\phi^2} The wavefunction at t=0 is \psi=ASin\phi Find the mean value of the observable Sin\phi Homework Equations The eigenfunction are \psi_n =...
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    Expansion of Cos(x) in Hermite polynomials

    I don't think you can do that as the higher hermite polinomials are not zero. I've figured the first and second integrals and they are c_0 = \frac{1}{\sqrt{e}^{4}} c_1 =0 c_0 differs from your method. i still need to find the last integral though.
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    Expansion of Cos(x) in Hermite polynomials

    [/itex]Homework Statement Find the first three coeficents c_n of the expansion of Cos(x) in Hermite Polynomials. The first three Hermite Polinomials are: H_0(x) = 1 H_1(x) = 2x H_0(x) = 4x^2-2The Attempt at a Solution I know how to solve a similar problem where the function is a polynomial of...
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    Limit of Sequence Homework: Find n22n/(n!)

    You can use this little theorem that is very useful in situatons like this one. Call your sequence a_n If a_n > 0 you calculate this limit lim {a_{n+1} \over a_n} if that limit is beetween 0 and 1, but not 1,then a_n{\rightarrow} 0 if that limit is greater than 1 then...
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    Find the limit of sequence (trig term)

    In your first question you show that your sequence lies beetween two sequence that both goes to zero 0≤An≤0 this implies An → 0 It's important that you show that it lies BEETWEEN two sequences. In your secondo question you show that your question is less than infinity, that does not make it go...
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    Rational Completeing the Square

    you went from x^2 +bx + (\frac{b}{2})^{2} to (x+b)^{2} and not to (x+\frac{b}{2})^{2}
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    Proving Uniqueness of Addition in Natural Numbers

    Nevermind i see where it's wrong :grumpy:
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