In quantum field theory, the vacuum state (also called the vacuum) is the quantum state with the lowest possible energy.
Generally, it contains no physical particles.
Zero-point field is sometimes used as a synonym for the vacuum state of an individual quantized field.
According to present-day understanding of what is called the vacuum state or the quantum vacuum, it is "by no means a simple empty space", and again: "it is a mistake to think of any physical vacuum as some absolutely empty void."
According to quantum mechanics, the vacuum state is not truly empty but instead contains fleeting electromagnetic waves and particles that pop into and out of existence.
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