Recent content by tim85ruhruniv

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    Solving Tensor Integration on a Unit Sphere: Help Needed

    hey ! Thanks guys for looking at my work. I can't see how the indices don't add up... maybe i am missing something... but Each component of \[ \mathbf{P}\] will be a function of the \mathbf{\mathrm{D}^{-1}} tensor. about division by the tensor.. x=\mathbf{D}y for some 'x'...
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    Solving Tensor Integration on a Unit Sphere: Help Needed

    Could someone help me out ?? I tried this integration over the surface of a sphere of unit radii, \[ P_{mn}e_{m}\otimes e_{n}=\frac{1}{D_{pq}e_{p}\otimes e_{q}}\int e_{m}\otimes e_{n}dS_{r=1}\] and I always get \[ 4\pi e_{m}\otimes e_{n}\] and the 'D' tensor as it is.. I am...
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    News Decline and fall of the Nobel Peace Prize

    Someone please nominate me for the Physics Nobel Next year... I have lots of vision, I 'hope' to unify all the theories consistently. I am highly motivated tooo , all i think about is physics everyday... if possible my friend (he works in McDonalds) tooo, he is a visionary, highly motivated by...
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    2nd Order ODE,Homogeneous,Non-Constant Coeff.

    phew after some hits and misses got it finally :) \[ y=ln\left(c_{o}+xk\right)\] seems to solve the equation...
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    2nd Order ODE,Homogeneous,Non-Constant Coeff.

    Hi, I am trying to guess the solution for this i am sure the solution involves a ln(x) so that i can reduce the order to find the general solution but i just can't seem to find it... any suggestions ?? \[ (c_{o}+xk)y''+ky'=0\] with ths usual boundary conditions...
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    Integral over a sphere with the dirac delta function

    hey guys, thanx a lot but i got it finally. by the way... i posted this problem in another section too and i don't know how to delete it... Thanx...
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    Integral Over a Sphere with dirac delta function

    hey, I Just got it, I used this substitution. \[ \intop_{0}^{\pi}\intop_{0}^{2\pi}f(cos\varphi sin\theta,sin\varphi sin\theta,cos\theta)sin\theta d\theta d\varphi\] the radius that i used in the variable substitution is not the same as the unit radius.
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    Integral over a sphere with the dirac delta function

    Homework Statement \[ \underset{\left|\underline{\xi}\right|=1}{\int}\delta_{0}\left(\underline{\xi}\cdot\underline{z}\right)dS_{\xi}=\intop_{0}^{2\pi}d\varphi\intop_{-r}^{+r}\delta_{0}\left(\varsigma\right)\frac{d\varsigma}{r}=\frac{2\pi}{r}\] The \delta_{0} is the dirac delta function.the...
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    Integral Over a Sphere with dirac delta function

    Hi, I am not really sure whether its over the surface of the sphere or the Volume, the problem and the solution are given below, I want to know how it has been solved. The \delta_{0} is the dirac delta function. \[...
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    Unforeseen Differentiation Problem in Chemical Concentration Equation

    Is this Right ? \[ =-\frac{1}{2}\left(\underset{k}{\sum}\left[n_{k}+\theta n_{j}^{\star}\right]z_{k}^{2}\right)^{-\frac{3}{2}}n_{j}^{\star}\nabla\underset{k}{\sum}\left[n_{k}+\theta n_{j}^{\star}\right]z_{k}^{2}\] \[ +\frac{1}{2}\underset{k}{\sum}\left[n_{k}+\theta...
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    Unforeseen Differentiation Problem in Chemical Concentration Equation

    I was working on some of my own equations and today i ended up with this differentiation thinghy, I never expected this in my equation but it just turned up :( so if there's anybody out there who loves to solve math please give this a try :) maybe its too simple :) ... i am just having doubts...
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    Being an Engineer I am bad in Engineering, why?

    I am good in Mathematics, the more the abstract the better, but when it comes to phsyical situations or physical problems in Engineering with simple formulae then there's a problem :( I have really spent a lot thinking about it, i still do like the Engineering way and also the Mathematical...
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    Being an Engineer I am bad in Engineering, why?

    I agree with you, I actually want to find out what am I good in, Am I a Mathematician without an undergrad Math degree or an Engineer who has to work much harder and find out if i still have the aptitude ... Do u have any suggestions which can help me decide ?? I however am not planning...
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    Being an Engineer I am bad in Engineering, why?

    well, i find it quite difficult to visualize stuff like mal4mac says,do you still think i can make a good engineer ? coz me having plans to do start my Ph.D in a few months. One more question, I thought probably i will finish My PhD and then get into the industry, anybody here who has done...
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    Being an Engineer I am bad in Engineering, why?

    hi, Thanks a lot for your suggestions :), The reason I wanted to read those books were because there are 2 guys in my class who have completed their bachelors degree in Mathematics(Hons.) and often they start talking about Topology, Hilbert spaces blah blah during the finite element...
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