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Zero-point energy, also called ''quantum vacuum zero-point energy'', is the lowest possible energy that a quantum mechanical physical system may have; it is the energy of its ground state. All quantum mechanical systems undergo fluctuations even in their ground state and have an associated zero-point energy, a consequence of their wave-like nature. The uncertainty principle requires every physical system to have a zero-point energy greater than the minimum of its classical potential well. This results in motion even at absolute zero. For example, liquid helium does not freeze under atmospheric pressure at any temperature because of its zero-point energy. The concept of zero-point energy was developed by Max Planck in Germany in 1911 as a corrective term added to a zero-grounded formula developed in his original quantum theory in 1900.〔 The term ''zero-point energy'' is a translation from the German ''Nullpunktsenergie''.〔 Vacuum energy is the zero-point energy of all the fields in space, which in the Standard Model includes the electromagnetic field, other gauge fields, fermionic fields, and the Higgs field. It is the energy of the vacuum, which in quantum field theory is defined not as empty space but as the ground state of the fields. In cosmology, the vacuum energy is one possible explanation for the cosmological constant.〔 〕 A related term is ''zero-point field'', which is the lowest energy state of a particular field.〔 〕 Scientists are not in agreement about how much energy is contained in the vacuum and for what purpose if any it could be used. Quantum mechanics requires the energy to be large as Paul Dirac claimed it is, like a sea of energy. Other scientists specializing in General Relativity require the energy to be small enough for curvature of space to agree with observed astronomy. The Heisenberg uncertainty principle allows the energy to be as large as needed to promote quantum actions for a brief moment of time, even if the average energy is small enough to satisfy relativity and flat space. To cope with disagreements, the vacuum energy is described as a virtual energy potential of positive and negative energy.〔 〕 While much is known about physical laws, little is known about how the laws are contained in nature, or how the gauge group finds expression in physical actions. Much theoretical work has been done on symmetry groups and topics related to the Standard Model with expectations that a Theory of Everything might be found using fundamental principles to describe the Zero Point Energy, as well as interactions of physical laws and the observed particles of physics. An example is given that Kaluza Klein theory found the Maxwell Equations by adding a fifth dimension to Albert Einstein's field equations. Additional work is continuing in 10 to 12 dimensions of Super Symmetry to describe the vacuum and actions that occur in it.〔 〕 Popular choices for the unifying group are the special unitary group in five dimensions SU(5) and the special orthogonal group in ten dimensions SO(10).〔 〕 ==History== In 1900, Max Planck derived the average energy of a single ''energy radiator'', e.g., a vibrating atomic unit, as a function of absolute temperature: : where is Planck's constant, is the frequency, is Boltzmann's constant, and is the absolute temperature. In a series of works from 1911 to 1913, Planck proposed his ''second quantum theory'', in which he introduced the zero-point energy. Only the emitted radiation was attributed to discrete energy quanta, while the absorbed radiation could be continuous in energy. From these ideas, he found that the average energy of an oscillator is : Soon, the idea of zero-point energy attracted the attention of Albert Einstein and his assistant Otto Stern. They attempted to prove the existence of zero-point energy by calculating the specific heat of hydrogen gas and compared it with the experimental data. However, after assuming they had succeeded and after publishing the findings, they retracted the support of the idea because they found Planck's second theory may not apply to their example. In 1916 Walther Nernst proposed that empty space was filled with zero-point electromagnetic radiation.〔 Then in 1925, the existence of zero-point energy was shown to be “required by quantum mechanics, as a direct consequence of Heisenberg's uncertainty principle” in Werner Heisenberg's famous article "Quantum theoretical re-interpretation of kinematic and mechanical relations". 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Zero-point energy」の詳細全文を読む スポンサード リンク
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