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emanaly
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Are we sure about the existence of virtual particles?
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Existence of virtual particles
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In summary, according to the speaker, virtual particles definitely exist as mathematical factors in a calculation via perturbation-series expansion, of the interaction probabilities of real particles. Whether they exist as concrete physical entities in an ontological sense is a matter of interpretation. It is still a matter of debate among physicists as to what the ontological status of virtual particles really is. However, there is some evidence that suggests they do have an existence. One possible explanation for this is the energy-time uncertanity relation, which holds even in classical physics. Although there is no direct proof that energy can be accurately measured during any short period of time, most particle physicists seem to neglect other interpretations of quantum mechanics.
- #2
jtbell
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Virtual particles definitely exist as mathematical factors in a calculation via perturbation-series expansion, of the interaction probabilities of real particles. Whether they exist as concrete physical entities in an ontological sense is a matter of interpretation. (as are many ontological questions in quantum physics)
- #3
mjsd
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they are called "virtual" particles for a good reason because they *are* virtual!
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emanaly
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jtbell said:
But, couldn't Casmir effect and Lamb shift be considered as strong evidence for the existence of virtual particles?
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mjsd
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your definition of "existence" seems different from what others are implying. firstly, clear up your mind with the what you really mean by "existence",
whether it has to be something concrete like "you can see it" and "touch it" or something that simply has real effects on other things in a defined way or whatever.. otherwise, you are not really asking the question correctly. It is like the situation of "fear of the unknown", while you know something is out there causing ppl to fear, but you don't know what it is really. But you can see its effect on ppl and when there are rumours that the "thing" shall materialise, ppl response accordingly... etc. but does this what you mean by real existence?
to me there is no good answer to this. it is a matter of interpretation as jtbell pointed out
whether it has to be something concrete like "you can see it" and "touch it" or something that simply has real effects on other things in a defined way or whatever.. otherwise, you are not really asking the question correctly. It is like the situation of "fear of the unknown", while you know something is out there causing ppl to fear, but you don't know what it is really. But you can see its effect on ppl and when there are rumours that the "thing" shall materialise, ppl response accordingly... etc. but does this what you mean by real existence?
to me there is no good answer to this. it is a matter of interpretation as jtbell pointed out
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The usual calculation of the Casimir effect can be taken as an evidence (though not proof) for the existence of the zero-point energy. This is not the same as virtual particles.emanaly said:
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By the way, perturbative calculation expressed in terms of Feynman diagrams can be used even in classical physics. Does it mean that virtual objects exist even in classical physics? No. So why one would like to use a different interpretation in quantum physics? ONLY because the interpretation of quantum physics is unclear by itself, so it does not matter if we add some additional confusion.
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emanaly
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Thanks for all answers, but I still have some questions, I would like someone help me in answering them.
1-How another interpretation of QM explain a virtual particle created from nothing (virtual particle depend highly on energy- time uncertanity)?
2-How the energy -time uncertanity relation still hold, while it is not a fundamental relation in QM as I read in Quantum mechanics: Myths and facts arXiv:quant-ph/0609163v2 16 Apr 2007?
3-Is there an experimental proof which shows that energy can be measure with any accuracy during any short period of time?
4-Why most of particle physics physicists don't pay attention to other interpretation of QM(as much as I know) ?
1-How another interpretation of QM explain a virtual particle created from nothing (virtual particle depend highly on energy- time uncertanity)?
2-How the energy -time uncertanity relation still hold, while it is not a fundamental relation in QM as I read in Quantum mechanics: Myths and facts arXiv:quant-ph/0609163v2 16 Apr 2007?
3-Is there an experimental proof which shows that energy can be measure with any accuracy during any short period of time?
4-Why most of particle physics physicists don't pay attention to other interpretation of QM(as much as I know) ?
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FAQ: Existence of virtual particles
1. What are virtual particles?
Virtual particles are particles that are believed to exist temporarily as a result of quantum fluctuations in the vacuum. They are not directly observable, but their effects can be measured through their interactions with other particles.
2. How do virtual particles come into existence?
According to quantum field theory, virtual particles are constantly popping in and out of existence due to the uncertainty principle. This means that the energy and time of these particles are not precisely defined, allowing them to briefly exist before disappearing again.
3. Can virtual particles be detected?
No, virtual particles cannot be detected directly. They are too short-lived and do not have enough energy to be measured. However, their effects can be observed through their interactions with other particles, such as changes in energy levels or the creation of new particles.
4. Do virtual particles violate the law of conservation of energy?
No, virtual particles do not violate the law of conservation of energy. This is because they only exist for a very short period of time and their energy is borrowed from the vacuum, which can later be returned. The total energy of the system remains constant.
5. How do virtual particles affect our understanding of the universe?
Virtual particles play a crucial role in our understanding of quantum mechanics and the behavior of subatomic particles. They also have implications for the creation and evolution of the universe, as well as the behavior of black holes. Their existence challenges our traditional understanding of reality and highlights the strange and complex nature of the quantum world.