Discover Questions

Given U= ln(x squared + y squared)Show that it is harmonic hence find a conjugate Harmonic function and write the function f(z)..? Ax - by + bx - ay? GPS uses signals from
A. Satellites to determine position B. Land radio stations to determine position? Would 'subspace communication' in the Star Trek universe map over to 'internet communication' in our universe? Ahmadinejad=Trump?