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First let us address "emty space". Empty space is a theoretical concept, a space where there is no matter and no energy. In our universe, no matter how far away one goes in space, it is not empty. It contains the cosmic microwave background radiation, cool photons, which is at a temperature of 2.7 K . Within quantum mechanics and elementary paricles, the ...

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The universe is not EMPTY. It is governed by dark matter (80%)!.The universe is also filled with neutrino. THE universe wouldn't then be expanding because new matter particles is being created(however they again disappear). Think it like a balloon being blown, as more particle goes in, the balloon expands. In other words, expansion is directly proportional ...

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Such phenomena as Casimir effect (especially dynamic version of the effect) and Lamb shift are typical manifestations of the quantum fluctuations. An existence of quantum fluctuations is really intuitive fact if you use an uncertainty principle, which tells us that particles can pop out of the vacuum during a very short time interval.

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First have a look at my answer to Black holes and positive/negative-energy particles for some background on Hawking radiation. The pairs of virtual particles analogy is just an analogy and not what actually happens. In fact virtual particles don't really exist in the way that real particles do - see this article by Matt Strassler for more on this. But your ...

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The amplitude for low-energy muon scattering mediated by $Z$ bosons is given the the muon's "weak charge," in the same way that the amplitude for scattering mediated by photons is given by the electric charge. In units where the weak charge of the neutrino is 1, the weak charge of the charged leptons is suppressed; I think at first order it's ...

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You have no way to know if the virtual particle is a gamma or a Z. Actually, it does not really make sense, since no measurement can tell you what has been exchanged. You always have to envisage all the possibilities resulting from the perturbative series used to describe the theory. It's a bit as asking in the double slits young experiment, which slit has ...

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So how can the same virtual photons give rise to 2 different properties? The photon is an elementary particle, and in the quantum field theoretical framework, an electromagnetic field exists in all (x,y,z,t) which has zero vacuum expectation value unless a photon exists there, the excitation of the field. What is the vacuum expectation value? It is the ...

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Try to start from the end and recapitulate, what was unknown in Maxwell's time. Electrons, neutrons, protons as well as their antiparticles have spin. This spin carries an angular momentum. This we know since Einstein and de Haas carried out their experiment with electrons. Furthermore it is well known, that parallel to the rotational axis of this intrinsic ...

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"Virtual" is not a property of a particle at all. And it is not true that pure electric and magnetic fields are "made out of virtual photons" or that a combined electromagnetic field is "made out of real photons". A "virtual particle" is not a particle. It is an internal line in a Feynman diagram, which is in turn a graphic notation for a certain integral. ...

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