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In quantum field theory, the quantum vacuum state (also called the quantum vacuum or vacuum state) is the quantum state with the lowest possible energy. Generally, it contains no physical particles. The term zero-point field is sometimes used as a synonym for the vacuum state of a quantized field which is completely individual. [clarification ...
Thus, according to the theory, even the vacuum has a vastly complex structure and all calculations of quantum field theory must be made in relation to this model of the vacuum. The theory considers vacuum to implicitly have the same properties as a particle, such as spin or polarization in the case of light, energy, and so on. According to the ...
In theoretical physics, quantum field theory (QFT) is a theoretical framework that combines classical field theory, special relativity, and quantum mechanics. [ 1 ] : xi QFT is used in particle physics to construct physical models of subatomic particles and in condensed matter physics to construct models of quasiparticles .
In quantum theory however there is always an "external" field, namely the source-free or vacuum field E 0 (t). According to our earlier equation for a k λ ( t ) the free field is the only field in existence at t = 0 as the time at which the interaction between the dipole and the field is "switched on".
In quantum field theory, a false vacuum [1] is a hypothetical vacuum state that is locally stable but does not occupy the most stable possible ground state. [2] In this condition it is called metastable. It may last for a very long time in this state, but could eventually decay to the more stable one, an event known as false vacuum decay.
The QED vacuum is subject to fluctuations about a dormant zero average-field condition; [4] Here is a description of the quantum vacuum: The quantum theory asserts that a vacuum, even the most perfect vacuum devoid of any matter, is not really empty.
In quantum field theory, the theta vacuum is the semi-classical vacuum state of non-abelian Yang–Mills theories specified by the vacuum angle θ that arises when the state is written as a superposition of an infinite set of topologically distinct vacuum states.
After the development of quantum field theory in the 1940s, the first to address contributions of quantum fluctuations to the cosmological constant was Yakov Zeldovich in the 1960s. [8] [9] In quantum mechanics, the vacuum itself should experience quantum fluctuations. In general relativity, those quantum fluctuations constitute energy that ...