Information AboutNormal Order |
| CATEGORIES ABOUT NORMAL ORDER | |
| quantum field theory | |
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Since Quantum Mechanical Hamiltonian s consist of Operators , they depend on the order of these. When quantizing a Classical Hamiltonian one therefore has some freedom when choosing the operator order, and these choices lead to differences in Ground State Energy . Normal order only applies to Free Field theories. The normal order of the operators is the choice that leads to ''zero ground state energy''. It puts all Annihilation Operator s to the right, and all Creation Operator s to the left, leading to a ground state Expectation Value of 0: | ||
| :<math>0 | \langle 0 N(K) 0
angle </math> |
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| :<math>:\phi(x)\chi(y): | \phi(x)\chi(y)-\langle\Omega\phi(x)\chi(y)\Omega
angle</math> |
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| Where &Omega> Is The | "http://wwwinformationdelightinfo/encyclopedia/entry/vacuum_state" class="copylinks">Vacuum State Each of the two terms on the right hand side typically blows up in the limit as y approaches x but the difference between them has a well-defined limit This allows us to define :&phi(x)&chi(x): |
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