Recent content by TonyS

Jeff, hi, I think it depends which version of the mass cancellation field generator you're thinking about. Obviously not the Mk I as that had a nasty tendency to generate negative inertia fields and promptly self annihilate, so it never got into production beyond the prototype stage. I think the...

The 'Further Reading' section of Quantum Field Theory for the Gifted Amateur by Lancaster and Blundell recommends V Radovanovic, Problem book in quantum field theory 2nd Edition, Springer, Berlin (2008) 'for those eager to practise, as it contains a useful set of solved problems.' I am not...

Dirac would have been giving lectures on quantum mechanics at Cambridge by 1930

As I understand it, the choice of a right hand rule for defining the cross product is independent of the choice of coordinate system. By convention, the right hand rule is always used in defining the vector cross product, regardless of the handedness of any particular coordinate system.

Lev Landau used to work reclining on a sofa - (just saying).

If you start out with a tile cornered at the origin in the xy plane then lift the corner that was lying at (5,5,0), the corners that started out at (5,0,0) and (0,5,0) will certainly not have the x and y coordinates that you have assigned in your modification of the problem. Cut out a square of...

Visualise vector displacements along the edges of the tile and think about what happens to those vectors when the corner of the tile is lifted. Then think about how you could use those vector displacements to move from (0,0) to the diagonally opposite corner.

Try thinking about the problem in terms of vector displacements of the corners of the tile.

The square of the period is proportional to the cube of the radius, as you indicated in your original post, aside from a typo, I think. This is one of Kepler's laws, by the way.

Yes, this was the aspect of quantum mechanics that Landau was discussing.

The physics of the problem allows you to find an expression for the orbital period as a function of r, that involves your unknown constants. You know the values of T and r for one particular case, namely the spacestation. The same relation between T and r also holds for the telescope, with the...

It is possible to solve your problem without knowing the value of G or the mass of the Earth.

Landau points out in vol 3 of the course of theoretical physics, that it is impossible to formulate the basic concepts of quantum mechanics without using classical mechanics (paragraph 1). That, surely, qualifies as weird ?

I have found that the way ideas are presented can dramatically affect one's level of interest. Feynman was an inspirational communicator, take a look here, for example http://www.bbc.co.uk/iplayer/episode/p018dvyg/horizon-19811982-9-the-pleasure-of-finding-things-out I don't know what level of...

callmespitfire, I find your post fascinating, to me it illustrates the difficulty we sometimes have with physics because of the way our mind visualises ideas. You might want to consider the idea of something moving in a straight line to a sufficient approximation, where 'sufficient' is...