Recent content by lurathis

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    Schwarzschild metric assistance

    Ah, that makes perfect sense. Excellent then! Thanks for helping me derive this (without a class or anything in this stuff it can be pretty tough).
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    Schwarzschild metric assistance

    That was extremely helpful, thanks. Oh and that was meant to be a negative sign in front of the c^2... just mistakenly left it out of the post. I'm not sure if I followed you to the letter, but I read through your post and then ran with the idea (perhaps deviating a little). Since my...
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    Schwarzschild metric assistance

    Yup, fabulous. After doing all that and solving for my A(r) and B(r), as well as setting a constant equal to c^2 to accommodate the minkowski metric as r approaches infinity, I end up with: d\tau^2 = (1+\frac{1}{Kr})^{-1}dr^2 + r^2(d\theta^2 + \sin^2\theta d\phi^2) + c^2 (1+\frac{1}{Kr})dt^2...
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    Calculating Chances of Descending Order with 36 Cards

    I thought you meant consecutively descending. Ok, so the way I thought about it was this: You can add the number of ways you can get a descending order where your highest card (call it M) is 4 (since M can't be less than 4), plus the number of possibilities when M=5, M=6, all the way to M=36...
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    Calculating Chances of Descending Order with 36 Cards

    Actually, your estimate is much larger than the actual number of possibilities. Try to think of it this way: How many possibilities are there for the first card? (Ans: Obviously 36) How many possibilities are there for the second card? (Hint: Not 36) How many possibilities are there for...
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    Calculating Chances of Descending Order with 36 Cards

    It's actually fairly simple. First you can easily determine how many different sets of 4 cards can you get that are in descending order, and you can probably figure out how many total hands there are. And well, yea... you know what to do from there.
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    Calculating Chances of Descending Order with 36 Cards

    Well how many different sets of 4 cards can you get that are in descending order? (i.e. {36, 35, 34, 33} is one, {35, 34, 33, 32} is another... how many are there?)
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    Schwarzschild metric assistance

    I see. That would explain a lot then because I was summing the entire thing because of that extra repeated index 'p' (not just summing the terms with p). Wait, since nothing is fixing p, don't you mean R^1{}_{111} = \Gamma^1{}_{11,1}-\Gamma^1{}_{11,1} + (\Gamma^1{}_{11} \Gamma^1{}_{11}...
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    Schwarzschild metric assistance

    Okay, Maxima seems correct as it would end up giving you the correct Schwarzschild metric. So I've come up with a system of checkpoints to see where I'm making my mistake. If you could possibly flag the checkpoint that is wrong, that would really help me try to fix my error. Maxima agrees...
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    Schwarzschild metric assistance

    That looks fantastic, thanks. I'm not sure why my way kept getting a strange result, but now that I have this to go by I can do some tests. Thanks a lot Pervect. This program looks neat :smile:
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    News China more popular than U.S. overseas

    I agree completely, but just as a nit-picky note, I believe you mean Colombia (It's more of a pet-peeve than anything else I guess... it's just that being Colombian and seeing your country constantly spelled like a US/Canadian city get's on that pet-peeve list real fast).
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    Schwarzschild metric assistance

    Pervect, this is what you got using my form of the metric, right? Do you also use the same Christoffel symbols I've been using? \Gamma^1{}_{1 1} = \frac{A'}{2A} \Gamma^2{}_{2 1} = \Gamma^3{}_{3 1} = \Gamma^2{}_{1 2} = \Gamma^3{}_{1 3} = \frac{1}{r} \Gamma^3{}_{3 2} = \Gamma^3{}_{2 3} =...
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    Schwarzschild metric assistance

    Whilst redoing it on my own, and trying to simplify, I actually did A(r)*R_tt - B(r)*R_rr = 0. (Only to then come back to the forum and realize that is what you suggest). However, I end up with: \frac{6}{r^2} + \frac{(B')^2}{4B}(7 + \frac{1}{B}) + \frac{1}{r}(\frac{B'}{B} + \frac{A'}{A}) -...
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    Schwarzschild metric assistance

    So the two Christoffel symbols I had incorrect didn't end up being present in the equations for R_{1 1} and R_{4 4} anyway so no progress there. Nevertheless, I am going back and doing the whole thing over to see if I can figure something out.
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    Ricci components in Schwarzschild solution

    I'm working this out for myself (https://www.physicsforums.com/showthread.php?t=80565) and I ended up with all the same Christoffel symbols except for one: \Gamma^1{}_{4 4} = \frac{-A'}{2B} (Note: If you're looking at my thread, I defined my A and B in reverse. So your A is my B and vice...
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