Question #71519

1 Answer
Jan 11, 2015

The Casimir effect is a small attractive force that acts between two close parallel uncharged conducting plates. It is due to quantum vacuum fluctuations of the electromagnetic field.

According to the quantum theory, the vacuum contains virtual particles which are in a continuous state of fluctuation .Casimir realised that between two plates, only those virtual photons whose wavelengths fit a whole number of times into the gap should be counted when calculating the vacuum energy. The energy density decreases as the plates are moved closer, which implies that there is a small force drawing them together.

The attractive Casimir force between two plates of area A separated by a distance L can be calculated to be,

# F = {( π h c)/ ( 480 L4)}A#

where h is Planck's constant and c is the speed of light.

What is plancks constant

a fundamental constant, equal to the energy of a quantum of electromagnetic radiation divided by its frequency, with a value of #6.626 × 10−34 # joules.

I Was to lazy to type so i copied it from http://math.ucr.edu/home/baez/physics/Quantum/casimir.html
There are some nice examples there so i recommend you check it out