The discussion centers on the properties of vacuum, specifically addressing why it is considered to have characteristics such as permeability and permittivity despite being described as "empty." The scope includes conceptual exploration and theoretical implications related to vacuum in physics.
Participants do not reach a consensus; multiple competing views regarding the nature of vacuum and its properties are presented, with some arguing for a more dynamic understanding of vacuum while others maintain traditional views.
The discussion reflects varying interpretations of vacuum properties, with limitations in definitions and assumptions about the nature of space, fields, and particles not fully resolved.
jijopaul said:I'm a fresher in PF. If I'm posting indecently, please forgive..
Vacuum is something empty. It contains nothing. Then why should it have properties like permeability, permittivity etc.?
There is not a definite line differentiating virtual particles from real particles — the equations of physics just describe particles (which includes both equally). The amplitude that a virtual particle exists interferes with the amplitude for its non-existence; whereas for a real particle the cases of existence and non-existence cease to be coherent with each other and do not interfere any more. In the quantum field theory view, "real particles" are viewed as being detectable excitations of underlying quantum fields. ... In this sense, virtual particles are an artifact of perturbation theory, and do not appear in a non-perturbative treatment.