Recent content by raisin_raisin

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    RLC Series/Parallel Impedance Near Resonance

    Thanks for your reply, I did not post them initially as I cannot get very far. Sorry for bad texing I can't figure out why it won't work. Parallel case: Putting over common demoninator \be Z^{P}=\frac{1}{i\omega C +\frac{1}{i\omega L} + \frac{1}{R}} = \frac{i\omega LR}{-\omega^{2}RLC + R +...
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    RLC Series/Parallel Impedance Near Resonance

    Hey, The impedance of the series and parallel RLC circuit both tend to R near the resonant frequency (one is a min/ one is a max) so if I expand the frequency around this point I should be able to show they are the same for \delta \omega small right? For some reason I can't get it to work. Any...
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    Solving Projector Question on Mixed States

    A few months ago I wrote this line down, but it does not seem to follow any more. Am I mistaking a mistake now or when I first wrote it down? thanks ( | 0 \rangle \langle 0 | + | 1 \rangle \langle 1 |) \rho ( | 0 \rangle \langle 0 | + | 1 \rangle \langle 1 |) = | 0 \rangle \langle 0 |...
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    When to use H when to use U(H)?

    Hello, If the dynamics of the system are descibed by a Hamiltonian, H please could someone explain when should I be using |\right \psi(t) \rangle=H\left |\right \psi(0) \rangle and when to use |\right \psi(t) \rangle=U\left |\right \psi(0) \rangle where U=e^{-iHt/\hbar} Thank you
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    Simple linear differential equation

    Ah yes now I remember! Thank you very much
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    Simple linear differential equation

    Hey, I know this is easy I just can't remember how to do it. y(0)=0 and By''+y'=A A,B constants. So complementary solution Bm^{2}+m=0 \\ \text{ therefore } m=0, \frac{-1}{B} therfore y_{C} = C_{1}+C_{2}e^{-t/B} Not sure what to do for particular solution though because...
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    Systems of Linear Homogenous Differential equations with Constant Coefficients

    Hello, I am looking at different ways to solve Systems of Linear Homogenous Differential equations with Constant Coefficients that is \acute{x}=Ax (x and x' are vectors A is a matix) then the solutions are x= \xi e^{\lambda t} where \xi are the eigenvectors and \lambda the eigenvalues of A and...
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    Commutator, where have I gone wrong?

    :blushing: Oops, thanks!
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    Commutator, where have I gone wrong?

    Thanks for your reply, sorry I still can't see it though, could you explain why? Thanks again.
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    Commutator, where have I gone wrong?

    This is for the Pauli Matrics 0 and 1 are different Hilbert Spaces \left[(I-Z)_{0}\otimes(I-Z)_{1} , Y_{0}\otimes Z_{1}\right] =\left((I-Z)_{0}\otimes(I-Z)_{1}\right)\left(Y_{0}\otimes Z_{1}\right)-\left(Y_{0}\otimes Z_{1}\right)\left((I-Z)_{0}\otimes(I-Z)_{1}\right)...
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    Writing a matrix as an outer product expansion.

    Thank you very much (for the book recommendations as well :))
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    Writing a matrix as an outer product expansion.

    Hi, Can someone explain to me how to write a matrix as a sum of outer products like \left|\psi\rangle\langle\psi\right|? For example how would I do a CNOT gate? http://en.wikipedia.org/wiki/Controlled_NOT_gate I assume this is fairly easy since it is always assumed and I have kind of picked...
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    Feynman Looking for A Particle Version of QFT

    Feynman Looking for A "Particle Version" of QFT Hey, I think I read somewhere (though can't find it now) that Feynman was looking for a 'particle' version of quantum field theory which he didn't find but this instead led to the path integral approach of quantum mechanics. Can anyone shed any...
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