Recent content by ElDavidas

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    Medical Physics Career Options - Experiences from Graduates

    I just graduated recently with a 2:1 in Mathematics and am thinking of studying a Masters course in Medical Physics in 2008. I got a welcoming response from Aberdeen University (http://www.biomed.abdn.ac.uk/Courses/medphys.html) and am thinking of studying there. However, I'm trying to think...
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    Find a Square-Free Int. m such that Q[√m] = Q[ζ]

    The roots of that polynomial are the primative roots \zeta and \zeta^5. How would I now use this information?
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    Find a Square-Free Int. m such that Q[√m] = Q[ζ]

    Homework Statement Let \zeta be a primative 6-th root of unity. Set \omega = \zeta i where i^2 = 1. Find a square-free integer m such that Q [\sqrt{m}] = Q[ \zeta ] Homework Equations The minimal polynomial of \zeta is x^2 - x + 1 The Attempt at a Solution I was...
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    Is the Ideal I = < 6, 3 + 3sqrt(-17) > in Z[sqrt(-17)] a Prime Ideal?

    Homework Statement Take the ideal I = < 6, 3 + 3 \sqrt{-17} > in the ring Z [ \sqrt{-17} ]. Determine whether this ideal is prime or not. Homework Equations <18> = I^2 There is no element \alpha \in Z [ \sqrt{-17} ] such that 18 = \alpha^2 The Attempt at a Solution...
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    Is L isomorphic to sl(2,C)?

    Homework Statement Take L = \left(\begin{array}{ccc}0 & -a & -b \\b & c & 0 \\a & 0 & -c\end{array}\right) where a,b,c are complex numbers. Homework Equations I find that a basis for the above Lie Algebra is e_1 = \left(\begin{array}{ccc}0 & -1 & 0 \\0 & 0 & 0 \\1 & 0 &...
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    Proving Simplicity of Lie Algebra L: Basis Elements and Ideal Structure

    Take L to be a subspace of sl (2,R). (R is the real numbers) L = \left( \begin{array}{ccc} 0 & -c & b\\ c & 0 & -a\\ -b & a & 0 \end{array}\right) The basis elements of L are e_1 = \left( \begin{array}{ccc} 0 & 0 & 0\\ 0 & 0 & -1\\ 0 & 1 & 0 \end{array}\right)...
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    Another number theory proof

    Homework Statement Let p be an odd prime. Show that x^2 \equiv 2 (mod p) has a solution if and only if p \equiv 1 (mod 8) or p \equiv -1 (mod 8) The Attempt at a Solution Ok, I figured the more of these I try, the better I'll get at them. Assuming that x^2 \equiv 2 (mod p) has a...
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    Proving Number Theory: Prime Numbers and Congruences

    I'm not sure. Could you use the Euclidean Algorithm? I've also been trying to find a contradiction by assuming that gcd (x,p) \neq 1 .
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    Proving Number Theory: Prime Numbers and Congruences

    ok, so far my solution is as follows: x^3 \equiv a (mod p) Then x \equiv a^{\frac{1}{3}} (mod p) So by Fermat, x^{p-1} \equiv 1 (mod p) or a^{\frac{1(p-1)}{3}} \equiv 1 (mod p) Would I need to say gcd (x,p) = 1? If so, how is this true?
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    Proving Number Theory: Prime Numbers and Congruences

    Homework Statement Let p be a prime number such that p \equiv 1 (mod 3) Let a be an integer not divisible by p. Show that if the congruence x^3 \equiv a (mod p) has a solution then a^{\frac{p - 1} {3}} \equiv 1 (mod p) The Attempt at a Solution Right, I'm not sure how...
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    Calculus of Variations (Canonical equations)

    Sorry, what do you mean by this?
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    Calculus of Variations (Canonical equations)

    I've been looking at this example for a while now. Could someone help? "Take the functional to be J(Y) = \int_{a}^{b} \( \alpha Y'^2 + \beta Y^2) dx For this F(x,y,y') = \alpha y'^2 + \beta y^2 and p = \frac{ \partial F}{\partial y'} = 2 \alpha y' \Rightarrow y' =...
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    Galois Correspondence for Subfields of K:Q

    Sorry, I don't understand this. Is finding the fixed point of \sigma (\alpha) something to do with the sign in between the 2 and \sqrt{2} not changing?
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    Galois Correspondence for Subfields of K:Q

    Homework Statement i) Find the order and structure of the Galois Group K:Q where K = Q(\alpha) and \alpha = \sqrt{2 + \sqrt{2}}. ii)Then for each subgroup of Gal (K:Q), find the corresponding subfield through the Galois correspondence. Homework Equations I get the minimal...
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