I Virtual Particles and Charge Screening

David Neves
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The following article says virtual particles don't exist or are just book keeping device.

https://www.physicsforums.com/insights/physics-virtual-particles

If that's the case, then how do you explain charge screening? We observe the charge of an electron to be less than the bare charge, or what it really is, because it is surrounded by a cloud of electron-positron pairs. Experiments confirm that the measured value of the electron's charge is determined by the distance fro which you measure it. How do you explain that without virtual particles?
 
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The "charge screening" or more accurately running of the electromagnetic coupling is due to quantum fluctuations. It can be calculated most simply by evaluating the photon self-energy. Of course, here "virtual particles" occur as explained in the Insights article, namely as internal line of Feynman diagrams, where they stand for propagators of the fields and thus well-defined mathematical expressions of perturbation theory.
 
You still need bookkeeping.

There probably is no answer at the intermediate level - to see what is going on involves the beta function in particular and the renormalization group equations in general, neither of which are undergraduate concepts.
 
Insights auto threads is broken atm, so I'm manually creating these for new Insight articles. Towards the end of the first lecture for the Qiskit Global Summer School 2025, Foundations of Quantum Mechanics, Olivia Lanes (Global Lead, Content and Education IBM) stated... Source: https://www.physicsforums.com/insights/quantum-entanglement-is-a-kinematic-fact-not-a-dynamical-effect/ by @RUTA
If we release an electron around a positively charged sphere, the initial state of electron is a linear combination of Hydrogen-like states. According to quantum mechanics, evolution of time would not change this initial state because the potential is time independent. However, classically we expect the electron to collide with the sphere. So, it seems that the quantum and classics predict different behaviours!
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