Occupation Number definition of Occupation Number in the Free Online Encyclopedia.

Occupation Number

in quantum mechanics and quantum statistics, a number that indicates the extent to which quantum states are filled by the particles of a quantum-mechanical system consisting of many identical particles. For a system consisting of fermions, or particles with half-integral spin, the occupation numbers may take only two values: 0 for empty states or 1 for filled states. For a system consisting of bosons, or particles with integral spin, the occupation numbers may take any nonnegative .integral values: 0,1, 2,. . . For a given system, the sum of all occupation numbers should be equal to the number of particles in the system.

Occupation numbers may also be used to describe the numbers of elementary excitations, or quasiparticles, of quantum fields. In this case, the sum of the occupation numbers is not fixed.

The occupation numbers averaged over a state in statistical equilibrium for ideal quantum gases are specified by either the Fermi-Dirac or the Bose-Einstein distribution function [see equation (19) in STATISTICAL MECHANICS]. The concept of occupation numbers underlies the method of second quantization, which is also called the occupation-number representation.

D. N. ZUBAREV

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No references found	Employment by Occupation 2006 Detroit United Region States percent percent of Occupation Number of Total Number Total Manage occupations 49,890 4. Detroit's changing workforce; Retiring baby boomers, evolving ... by Armstrong, Melissa / Detroiter The experiment [7] would allow one to identify an additional quantum state if its occupation number would not be suppressed by more than a factor of 200 compared to that for other states. Constraints on non-Newtonian gravity from the experiment on neutron ... by Protasov, K.V. / Journal of Research of the National Institute of Standards and Technology 1 HIV infection is devastating some occupations in Zambia and Uganda Zambia HIV-positive Occupation Number (percent) Mid wives 379 39 Nurses 370 44 Office workers or teachers 370 42 Traditional birth attendants 369 12 Uganda HIV-positive Occupation Number (percent) Mid wives 373 21 Nurses 381 11 Office workers or teachers 371 18 Traditional birth attendants 375 5 Note: Based on surveys conducted during December 1991-January 1992. 2. AIDS undermines development--and exacerbates poverty by AIDS Prevention and Mitigation In Sub-Saharan Africa: An Updated World Bank Strategy	occluded gases occluding junction occlusal disharmony Occlusion Occom, Samson Occoneechee Mountain State Natural Area Occoneechee State Park Occoquan Bay National Wildlife Refuge occult blood occult hydrocephaly occult mineral occult virus Occultation occulting bar occulting disk occulting light occulting quick-flashing light Occultism occupancy occupancy permit occupancy rate occupancy sensor occupant occupant load Occupation Occupation Number occupational acne Occupational Disease Occupational Disorder Occupational Diversification occupational ecology Occupational Hazard Occupational Hygiene occupational medicine occupational neurosis Occupational Safety and Health Administration Occupational Slang Occupational Therapy occupiable room occupied bandwidth occupy occurrence occurs check Ocean ocean basin ocean circulation Ocean City Ocean City State Park Ocean Conservancy Ocean County ocean current	Occupant Sensing System occupant weight sensor occupants occupants occupants occupants occupare occupare Occupate Occupate Occupatio Occupatio occupation occupation occupation Occupation (disambiguation) Occupation (disambiguation) Occupation (disambiguation) Occupation Air Post Occupation Analysis Document Occupation and Skill Computer-Assisted Researcher Occupation bridge Occupation Control System occupation currency Occupation Double occupation franchise occupation groupings occupation licence occupation license Occupation Newspaper Occupation Number Occupation of Atlanta Occupation of Iraq Occupation of Iraq Occupation of Japan occupation of position Occupation of the Golan Heights Occupation of the Golan Heights Occupation of the Ruhr Occupation Official Occupation Permit Occupation Postage Due Occupation Postal Tax Occupation Regular Issues Occupation Semipostal Occupation Special Delivery Occupation Specialty Qualification occupation time Occupation, Risk occupational occupational occupational occupational Occupational & Environmental Health Laboratory Occupational Access and Opportunity Commission occupational accident occupational acne Occupational Advisory Committee Occupational Allergic Bronchial Asthma Occupational Allergic Contact Dermatitis

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Employment by Occupation 2006 Detroit United Region States percent percent of Occupation Number of Total Number Total Manage occupations 49,890 4.

Detroit's changing workforce; Retiring baby boomers, evolving ... by Armstrong, Melissa / Detroiter

The experiment [7] would allow one to identify an additional quantum state if its occupation number would not be suppressed by more than a factor of 200 compared to that for other states.

Constraints on non-Newtonian gravity from the experiment on neutron ... by Protasov, K.V. / Journal of Research of the National Institute of Standards and Technology

1 HIV infection is devastating some occupations in Zambia and Uganda Zambia HIV-positive Occupation Number (percent) Mid wives 379 39 Nurses 370 44 Office workers or teachers 370 42 Traditional birth attendants 369 12 Uganda HIV-positive Occupation Number (percent) Mid wives 373 21 Nurses 381 11 Office workers or teachers 371 18 Traditional birth attendants 375 5 Note: Based on surveys conducted during December 1991-January 1992.

2. AIDS undermines development--and exacerbates poverty by AIDS Prevention and Mitigation In Sub-Saharan Africa: An Updated World Bank Strategy

Occoneechee Mountain State Natural Area

Occoneechee State Park

Occoquan Bay National Wildlife Refuge

occult blood

occult hydrocephaly

occult mineral