Wednesday, December 23, 2015

Hubble-collapse

can you show that the density inside a sphere which contracts according to a Hubble-law $\upsilon(r)\propto -r$ remains homogeneous? what's the relation between density $\rho$ and time $t$?

we wish all our readers and followers merry x-mas and a happy and successful year 2016. we hope to see you again in january.

Wednesday, December 16, 2015

Schwarzschild radius of electrons

if electrons are truly pointlike particles, would it be a problem for the field lines emanating from the charge to cross the Schwarzschild radius?

Wednesday, December 9, 2015

replacing Maxwell's equations

Maxwell's equations describe the sourcing and the time evolution of electric and magnetic fields. could you replace them with 1. charge conservation, 2. the Coulomb-law and 3. the Lorentz transformation for fields? would there be something missing?

Wednesday, December 2, 2015

gravitational wave interferometers

CQW celebrates its fourth anniversary!

imagine a Michelson-Morley-type interferometer for the detection of gravitational waves: are there directions in which it is insensitive to linearly polarised gravitational waves? what about circularly polarised gravitational waves?