Dirac Equation in the Spatially Flat Friedmann Model

Autor:	Kenneth J. Epstein
Rok vydání:	1999
Předmět:	Physics symbols.namesake Spinor Classical mechanics Physics and Astronomy (miscellaneous) Wave packet Dirac equation symbols Two-body Dirac equations Dirac algebra Dirac sea Hamiltonian (quantum mechanics) Causal fermion system
Zdroj:	General Relativity and Gravitation. 31:379-390
ISSN:	1572-9532 0001-7701
DOI:	10.1023/a:1026696812286
Popis:	The unitary transformation which diagonalizesthe field-free Dirac Hamiltonian in the spatially flatFriedmann-Robertson-Walker metric is analyzed, and apair of simultaneous first-order nonlinear differential equations is derived for the two parameters(two angles) that characterize the transformation. Theequations are solved approximately for a test particlewhose kinetic energy is small compared to its mass energy, and minimum-uncertainty wave packetsare constructcd from the solutions. It is found thatgeneral relativity limits the quantum mechanical spreadof the wave packets, but forces then to expand with the expanding space, as if they were embeddedin it. The massless Dirac equation is solved exactly forthe two-component neutrino spinor, and yieldsgeneralized nonspreading wave packets which display no quantum mechanical spread at all, but areconstrained to expand with the expanding space as theyfollow null geodesics.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::b5d52e53696a16585ec58845148417e5 https://doi.org/10.1023/a:1026696812286 Zobrazit plný text záznamu Full text from SpringerLink