Recent content by lewis198

A picture speaks a thousand words. In this video, at 41 seconds: [URL="http://www.youtube.com/watch?v=FBZWZfbxeJw"] Eugene R transfers power to a pulley attached to a rod but only the pulley spins. I am in the process of fabricating a pulley system like this. My question is: How is this done?

This is a bit embarrassing, but by convention does |0> = (1,0)^T and |1>=(0,1)^T, where we are in the basis of the eigenvectors of \sigma_{z}?

If I have a wide beam, parallel to the x axis, with its COM at the origin, then I want it to curve about the y axis, what would the elements of the strain tensor be? I have come to the conlusion that the beam would, for example,contract above x-axis and expand below it. But I don't know how...

My question is: What do PhD advisors look for in candidates that want to study Quantum Information Theory? I ask this so I can know what to focus my spare time studies on.

Sorry, to specify I mean theoretical- Quantum Information Theory.

To elaborate, are they looking for a specific last year thesis for example? I'm reading a four year physics MSci.

Thanks - I have another question if you don't mind- Is \delta_{i}^{i} summed over? i.e Is the above equal to \displaystyle\sum\limits_{i=0}^n \delta_{i}^{i} If so what determines n?

Ok thanks, got it. By the way, how come your Latex is showing and mine isn't?

is M_{ij}\delta ^{i}_{j} = M_{ii} also valid?

I am aware that the following operation: mathbf{M}_{ij} \delta_{ij} produces mathbf{M}_{ii} or mathbf{M}_jj However, if we have the following operation: mathbf{M}_{ij} \delta^i{}_j will the tensor M be transformed at all? Thank you for your time.

The total electric field is the vector sum of electric fields- is this the case with magnetic fields? Experience tells me a vector magnetic field can alter another vector magnetic field- for example, when you push two magnets together.

I understand that, but here we have the variables 'x'=(q+dq) and 'y'=(q'+dq') and we want an expansion for dq and dq'.

I'm going over the Landau's Mechanics, and can't get over two hurdles. The first is the following(I'm not good with latex here, so please bear with me): Landau asserts that the action S' between t1 and t2 of a Lagrangian L such that L is a function of (q+dq) and (q'+dq') minus the action S...

Thanks again. I used algebraic long division and trigonometric substitution and got the following solution: y-arctan((x+y)/a)=C This is not a so called 'closed' solution. Is that ok? Is this solution even meaningful?

thanks for the reply. What is the criteria for a substitution?