Recent content by petmal

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    Legendre Polynomials - expansion of an isotropic function on a sphere

    Well, I want to get C_{l}, right? That is why I apply P_{l} on the correlation function (1) and integrate - it removes P_{l} and the sum leaving C_{l} * some factor in l. Where do you see a mistake? Thanks.
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    Legendre Polynomials - expansion of an isotropic function on a sphere

    Hello. I don't know what to do with one integral. I am sure it is something very simple, but I just don't see it... For some reason I am not able to post the equations, so I am attaching them as a separatre file. Many thanks for help.
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    Durham vs Manchester in Astrophysics (Cosmology) - Postgraduate

    Hi all. I have been applying for graduate (research) studies in Astrophysics (I am interested in cosmology - CMB, SNIa, models...) at some UK universities - Imperial College, Durham, Glasgow, Manchester. All of them have research groups in the field of cosmology. So far I have received an...
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    Solutions of Friedmann Equations

    Thanks a lot, you opened my eyes... For some reason I didn't see the simple solution of plotting it as a parametric equation where x = t[\Theta] and y = R[\Theta]... I was probably expecting something more complicated...
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    Solutions of Friedmann Equations

    I doubt the result could be solved explicitly for R... Right now I've got three books in Astrophysics/Cosmology here, every of them provides the parametric solutions (above) and clearly explains how to get the age of the universe from it (expressing parameters in terms of...
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    Solutions of Friedmann Equations

    Thanks, you confirmed what I was thinking about. I guess this is what I don't know to do so I need R in terms of t... :blushing:
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    Solutions of Friedmann Equations

    Simply, say, I want to make a plot of evolution of the scale factor R vs. t. Such plots are probably in every book which has something to do with cosmology. To do this I need R as a function of t, unfortunatelly have no idea how to get it. When k = 0, it's a simple differential equation...
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    Solutions of Friedmann Equations

    Hello everybody, could somebody tell me how to get the scale factor as a function of time [R(t)] from the Friedmann Equations for a simple dust, pressureless universe when k != 0, \Lambda = 0. Mathematica 5.2 doesn't want to give me any solution and wherever I searched the best thing I got...
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    Two-D Gas: Entropy Calculation & Temperature/Chemical Potential

    Mistake in the equation It is probably too late, but I am quite sure that the equation should look like this: ]S=Nk\left[ \ln \left(\frac{A}{N}\right) + \ln \left(\frac{2\pi mU}{\hbar^2 N}\right) +2\right]
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