ZPEnergy.com - EnPsychLopedia on Zero Point Energy

In physics, the zero-point energy is the lowest possible energy that a quantum mechanical model of a physical system may possess; it is the energy of the ground state of the system. All quantum mechanical systems have a zero point energy. The term arises commonly in reference to the ground state of the quantum harmonic oscillator. In quantum field theory, it is a synonym for the vacuum energy, an amount of energy associated with the vacuum of empty space. In cosmology, the vacuum energy is taken to be the origin of the cosmological constant. Experimentally, the zero-point energy of the vacuum leads directly to the Casimir effect, and is directly observable in nanoscale devices.

The concept of zero-point energy, and the hint of a possibility of extracting "free energy" from the vacuum, has attracted the attention of amateur inventors. Numerous perpetual motion and other pseudoscientific devices, often called free energy devices, exploiting the idea, have been proposed. As a result of this activity, and its intriguing theoretical explanation, it has taken on a life of its own in popular culture, appearing in science fiction books, games and movies. As of 2006, there is no known practical method to extract usable energy from the vacuum, although mainstream research is being carried out by the Calphysics Institute, NASA's Glenn Research Center, and aerospace giant BAE Systems.

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