Recent content by varth

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    Static situations and electric fields - special relativity

    Homework Statement Is it possible to create an electrostatic field E(x) (in 3 spatial dimensions x and E is a vector of course) such that i) E(x) = a × x (cross product) ii) E(x) = (a.x) b (dot product between a and x) where a,b and non-zero vectors that do not depend on time and the...
  2. V

    Showing the sine-Gordon equation is satisfied.

    I believe that has done the trick, many thanks!
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    Showing the sine-Gordon equation is satisfied.

    Thanks for the reply! But I believe the expression sin(4arctan(...)), not sin(arctan(4...). I believe this complicates things?
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    Showing the sine-Gordon equation is satisfied.

    Homework Statement I am currently trying to show a the sine-Gordon equation is satisfied by a 'soliton-antisoliton' solution. Basically, I need to differentiate twice w.r.t. t and x separately and plug in everything as usual but my expression is getting extremely complicated and I don't know...
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    MATLAB Generating covariance matrices as defined in MATLAB

    Hi, I'm fairly new to MATLAB and I was wondering if you guys could help me out. If I have an N*N matrix, C where the (k,l)-entry is defined as: http://a3.sphotos.ak.fbcdn.net/hphotos-ak-ash3/556394_10151031836051952_2120388553_n.jpg Where x_i is from an N-vector where x_i is normally...