Casimirilmiönä

Casimirilmiönä refers to the Casimir effect, a physical phenomenon predicted by quantum field theory. It describes a tiny attractive force that arises between two uncharged, conductive plates placed very close to each other in a vacuum. This force is a direct consequence of the quantum vacuum, which is not truly empty but filled with fluctuating quantum fields.

These vacuum fluctuations can be thought of as temporary, virtual particles popping in and out of existence. When two parallel plates are brought close together, they impose boundary conditions on these fluctuations. Specifically, only certain wavelengths of these fluctuations can exist in the space between the plates, while others are excluded. The excluded wavelengths correspond to modes that would have existed in the absence of the plates.

This difference in the number of allowed vacuum fluctuation modes inside and outside the plates leads to an imbalance in radiation pressure. The pressure exerted by the vacuum fluctuations from the outside is greater than the pressure from the inside, resulting in a net inward force, which is the Casimir force. The strength of this force is inversely proportional to the fourth power of the distance between the plates, making it extremely weak and only noticeable at very small separations, typically on the nanometer scale. The Casimir effect has been experimentally verified and is an important demonstration of the reality of quantum vacuum energy.