Have you ever wondered how light travels through the vast expanse of space? It is the virtual particles that play a crucial role in determining the speed of light. These particles allow light to travel because light cannot travel in a pure vacuum.

A recent article  in Live Science also suggests that the speed of light may be changing and is determined by the reaction with virtual particles (from quantum fluctuations) thus showing that space is not the simple vacuum but a structured platform that determines the speed of light, vacuum energy and gravity. 

"Photons of light, as they fly through 'space', are captured and re-emitted by these virtual particles. Urban and his colleagues propose that the energies of these particles — specifically the amount of charge they carry — affect the speed of light. Since the amount of energy a particle will have at the time a photon hits it will be essentially random, the effect on how fast photons move should vary too."