Većina misli kako u vakumu svemira ne postoji sila otpora, ali tu se izgleda nešto čudno pomalja na horizontu.
Quote:
http://www.sciencealert.com/physicis...perfect-vacuum
One of the most fundamental tenets of modern physics is that in a perfect vacuum - a place entirely devoid of matter - no friction can possibly exist, because empty space cannot exert a force on objects travelling through it.
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orginal dokument:
Quote:
DOI: 10.1103/PhysRevLett.118.053601
ABSTRACT
We show how a simple calculation leads to the surprising result that an excited two-level atom moving through a vacuum sees a tiny friction force of first order in v/c. At first sight this seems to be in obvious contradiction to other calculations showing that the interaction with the vacuum does not change the velocity of an atom. It is even more surprising that this change in the atom’s momentum turns out to be a necessary result of energy and momentum conservation in special relativity.
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