I Wavelength of photons exchanged between charged particles

[Sophrosyne]

When two electrons approach each other, there is a repulsion between them by the exchange of a photon as the electromagnetic force carrier. Is there a general range of wavelength of such photons? Does it depend on how rapidly these electrons are approaching each other?

 

[Vanadium 50]

These are virtual photons. They are not real. They do not have wavelengths. You can't even count them.

 

[Sophrosyne]

These are virtual photons. They are not real. They do not have wavelengths. You can't even count them.

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What confuses me about that is that it seems the distinction between virtual and real photons greys out a little and is often not so distinct. Let me quote from this Wikipedia article:

"As a consequence of quantum mechanical uncertainty, any object or process that exists for a limited time or in a limited volume cannot have a precisely defined energy or momentum. This is the reason that virtual particles – which exist only temporarily as they are exchanged between ordinary particles – do not necessarily obey the mass-shell relation. However, the longer a virtual particle exists, the more closely it adheres to the mass-shell relation. A "virtual" particle that exists for an arbitrarily long time is simply an ordinary particle – in that sense electromagnetic waves, e.g. in a microwave oven, consist of real photons rather than virtual ones. (A typical power oven emitting microwaves of roughly λ=3cm at a power of 700 W produces 1026[PLAIN]https://wikimedia.org/api/rest_v1/media/math/render/svg/a9abdbae5cf3b55fda1e1574a27911e0aed30f19real photons per second.)

However, all particles have a finite lifetime, as they are created and eventually destroyed by some processes. As such, there is no absolute distinction between "real" and "virtual" particles. In practice, the lifetime of "ordinary" particles is far longer than the lifetime of the virtual particles that contribute to processes in particle physics, and as such the distinction is useful to make."
https://en.m.wikipedia.org/wiki/Virtual_particle

 

[Vanadium 50]

That Wikipedia article is a hot mess, with statements true in one context being sprinkled about in other contexts. Virtual photons are not real. They do not have wavelengths. You can't even count them.

 

[Nugatory]

What confuses me about that is that it seems the distinction between virtual and real photons greys out a little and is often not so distinct. Let me quote from this Wikipedia article:

Stuff like this is the reason that wikipedia is generally not an accepted source here.