Recent content by SoggyBottoms

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    Ultimate question: Why anything at all?

    I really don't have anything to add to the above discussion, but this question has crossed my mind a lot. Instead of a philosophical answer, shouldn't the answer lie in physics? Obviously I don't know what it is, but if we ever find an answer, wouldn't it be, for instance, an entropy related...
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    LaTeX Indenting Text in LaTeX: Is it Possible?

    I want to indent everything after the first line, but not the first line itself. So it needs to come out like this: Physicsforums is a very interesting place where you can learn a whole lot and such and so and such and so. Is this possible?
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    Relying on one book too much in an essay

    It does, and I've looked up those books and referenced to them instead where possible. I'm still left with a large chunk of citations to this book and outside of this book there is really not much information to be found about the subject.
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    Relying on one book too much in an essay

    I'm currently writing an essay and I'm finding myself using and quoting one particular book a lot. Obviously I'm referencing everything, but would it be a good idea to add something like 'In particular, I will make use of Bart Simpson's excellent book 'The Excellent Book' in my exploration...
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    Delta potential: Transmission coefficient

    Homework Statement Consider a double delta potential given by V(x) = c_+ \delta (x + \frac{L}{2}) + c_- \delta (x - \frac{L}{2}). The coherence between the amplitude A of an incoming wave from the left and the amplitude F of the outgoing wave to the right is given by: F = A \cdot...
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    Double delta potential - boundary conditions

    A double delta potential is given by V(x) = c_+ \delta (x + \frac{L}{2}) + c_- \delta (x - \frac{L}{2}). Use the discontinuity relation to find the boundary conditions in x = \pm \frac{L}{2} . The general solutions are: \psi(x) = \begin{cases} Ae^{ikx} + Be^{-ikx} & x < -\frac{L}{2}...
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    Can Normalizing a Wave Function be Simplified Using Trig Identities?

    At t = 0 a particle is in the (normalized) state: \Psi(x, 0) = B \sin(\frac{\pi}{2a}x)\cos(\frac{7\pi}{2a}x) With B = \sqrt{\frac{2}{a}}. Show that this can be rewritten in the form \Psi(x, 0) = c \psi_3(x) + d \psi_4(x) We can rewrite this to: \Psi(x, 0) = \frac{B}{2}\left[ c...
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    Calculating temperature from entropy

    Consider N >> 1 particles that can either be in groundstate \epsilon_0 or excited state \epsilon_1 and are thermally isolated, so the internal energy is fixed at U = (N - n) \epsilon_0 + n \epsilon_1. We want to calculate the temperature of this system. This is how I attempt it: First...
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    Solve Integral: \int_{-n \pi /2}^{n \pi / 2} y^2[1 + \cos(2y)] dy

    I have the following integral, but I don't know how to solve it: \int_{-n \pi /2}^{n \pi / 2} y^2[1 + \cos(2y)] dy , with n = 1, 3, 5... Any ideas?
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    Matrix Calculation Error: Finding the Correct Solution

    Homework Statement See attached image. The Attempt at a Solution I get a different solution: First multiply by \sqrt{2}, then {1 \choose -1} = {c + d \choose ci - di}. So we get c + d = 1 and so (1 - d)i - di = -1. Solving the last one gives 2di = 1 + i, so d = \frac{1 + i}{2i} =...
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    Eigenvectors, spinors, states, values

    It doesn't indeed, but they use all the terms interchangeably it seems, so it's confusing. Thanks.
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    Eigenvectors, spinors, states, values

    So all three terms are actually the same? At least as far as my introductory QM is concerned? Eigenvector = eigenspinor = eigenstate?
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