Recent content by Guffie

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    Fermi energy approximation for white dwarfs

    Hrm, So your saying that, as there are a large number of degeneracies in white dwarfs, due to the pauli exclusion principle each electron is somewhat stuck in it's state as neighbouring levels are occupied, so the electrons are essentially at rest? So the mean kinetic energy is zero and hence...
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    Fermi energy approximation for white dwarfs

    Hello, I have read several articles/websites which talk about modelling white dwarfs, In all of these papers they state that it can be assumed the electrons have temperature zero, i.e. T<<T_fermi. I haven't been able to find a solid explanation of why this is approximation is possible...
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    Fermi/Boson statistics partition function/probabilities

    The way I've been doing this is consistent with how I did the first question, multiplying the probability that one particle is in the ground state by the probability the other is in the ground state. I'm not sure what you mean by "two different Z's", the two Z's are the same, (1/Z)(1/Z) = 1/Z^2...
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    Fermi/Boson statistics partition function/probabilities

    In the fermion case, the state doesn't exist.. Is that what you mean? The probability is zero for that reason. So it's simply P = 0, as the state does not exist using fermi statistics. For bosons though it does exist, and it is when both atoms are at E=0, which means that the the...
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    Fermi/Boson statistics partition function/probabilities

    Thanks for your reply, Oh, So it should be For both particles in the ground state Fermi: P =(1/Z) When T->0 this probability should be zero right? But when you actually take the limit as T->0 , i.e. β->infinity, you'll see that P tends to infinity, not zero. That's why I'm a bit...
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    Fermi/Boson statistics partition function/probabilities

    Homework Statement If you have a three energy level system, with energies 0, A, B where B>A, which consists of only two particles what is the probability that 1 of the particles is in the ground state? What about if two of them are in the ground state? Do this using both fermi and boson...
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    Anyone know of some basic physics papers to 'critique'?

    Hey, I have been put in the position in which I have required to write a formal 'critique' of a physics related journal article. The catch is that I am limited to more basic theories as the people who will be reading the critique are from the facaulty of arts, which blew all of my ideas out...
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    Expectation value of potential energy of Ideal gas

    sorry I am pretty sure i can't use this result in answering the question, p = p0e^(-Cx/T_0) I think maybe you may have mixed up p the pressure and P(x) the distribution, which is what i was trying to find what i have been looking for was this <U> = (int_{-∞,∞} int_{0,10} dp dx U e^(-β...
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    Expectation value of potential energy of Ideal gas

    Sorry, i should have also noted that the question states "don't base your solution from already known knowledge of the conditions of the Earth's atmosphere." I have going with this distribution function so far.. but it was derived using p^2 = 2mE, which is the kinetic energy.. To answer...
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    Expectation value of potential energy of Ideal gas

    Homework Statement Say you have a large column of gas with insulating walls standing on the Earth's surface, which is L high and at room temperature (25degC) at the interface of the surface and column. Assuming the potential energy on the gas is only duel to gravity, U = mgx where x is the...
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    Reducing surface integral to line integral?

    thanks for your replies! ok sorry, i thought i could leave it general, the formula i have given is the boundary value term of the general solution to the heat equation, there a 3 terms, one associated with the driving function, one associated to initial conditions and one associated with...
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    Reducing surface integral to line integral?

    Homework Statement hi I am trying to adjust this general integral to my problem, my problem consists of a semi-infinite rod, i.e. x in [0,∞) the primed variables are the integration variables Homework Equations http://img339.imageshack.us/img339/5038/42247711.jpg The Attempt at a...
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    Applying boundary condition on heat equation

    sorry i don't follow the first thing you said, the cos term is cos(kβt), how is that zero at x = 0? its not zero at t = 0 either,
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    Applying boundary condition on heat equation

    with that approach you get a cos term aswell, that's one of the main problems I've been having, what your saying is to say the constant associated with that cos will be zero, then i guess it would work, but you'd have to add Q_0 to the solution, is there a way to solve the problem with...
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