Vacuum state — 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. The term zero point field is sometimes used as a synonym for the vacuum state… … Wikipedia
Vacuum energy — is an underlying background energy that exists in space even when devoid of matter (known as free space). The vacuum energy is deduced from the concept of virtual particles, which is itself derived from the energy time uncertainty principle. Its… … Wikipedia
Vacuum — This article is about empty physical space or the absence of matter. For other uses, see Vacuum (disambiguation). Free space redirects here. For other uses, see Free space (disambiguation). Pump to demonstrate vacuum In everyday usage, vacuum is… … Wikipedia
Vacuum manifold — In quantum field theory, the vacuum state may be degenerate. Each pure vacuum state generates its own superselection sector. The space of all pure vacuum states often has a manifold structure and is called the vacuum manifold.Vacuum manifolds… … Wikipedia
Vacuum (disambiguation) — In physics, Vacuum can refer to: *Vacuum, the absence of matter. *Vacuum state in quantum mechanics. *Suction. *Free space, a concept of electromagnetic theory, corresponding to a theoretical perfect vacuum .Vacuum, in different contexts, can… … Wikipedia
Vacuum expectation value — Quantum field theory (Feynman diagram) … Wikipedia
Vacuum forming — Vacuum forming, commonly known as vacuforming, is a simplified version of thermoforming, whereby a sheet of plastic is heated to a forming temperature, stretched onto or into a single surface mold, and held against the mold by applying vacuum… … Wikipedia
Vacuum tube — This article is about the electronic device. For experiments in an evacuated pipe, see free fall. For the transport system, see pneumatic tube. Modern vacuum tubes, mostly miniature style In electronics, a vacuum tube, electron tube (in North… … Wikipedia
Vacuum pump — A vacuum pump is a device that removes gas molecules from a sealed volume in order to leave behind a partial vacuum. The vacuum pump was invented in 1650 by Otto von Guericke. Types Pumps can be broadly categorized according to three… … Wikipedia
vacuum — I. noun (plural vacuums or vacua) Etymology: Latin, from neuter of vacuus empty, from vacare to be empty Date: 1550 1. emptiness of space 2. a. a space absolutely devoid of matter b. a space partially exhausted (as to the highest degree possible) … New Collegiate Dictionary