Summary
It is shown that the representation space of the conformal groupSO 4,2 is the Bargmann-Segal space of coherent states |w μ › of the non-Hermitian position operator\(\bar w_\mu ^ + \). The states |w μ › are coherent in the usual sense of minimal uncertainty ofx μ andp μ . The real part of\(\bar w_\mu ^ + \) gives the Hermitian position operatorx μ . Both operators fulfil the canonical commutation relations and are covariant under the conformal group. The imaginary part of\(\bar w_\mu ^ + \) describes the dispersion of position. The metric operatorG connecting\(\bar w_\mu \) with its adjoint\(\bar w_\mu ^ + \) gives the scalar product for various representations of the conformal group.
Riassunto
Si dimostra che lo spazio delle rappresentazioni del gruppo conformeSU 4,2 è lo spazio di Bergmann-Segal degli stati coerenti |w μ › dell’operatore di posizione non hermitiano\(\bar w_\mu ^ + \). Gli stati |w μ › sono coerenti nel senso usuale di minima incertezza dix μ ep μ . La parte reale di\(\bar w_\mu ^ + \) dà l’operatore di posizione hermitianox μ . Entrambi gli operatori soddisfano le relazioni di commutazione canoniche e sono covarianti rispetto al gruppo conforme. La parte immaginaria di\(\bar w_\mu ^ + \) descrive la dispersione di posizione. L’operatore metricoG che connette\(\bar w_\mu \) col suo aggiunto\(\bar w_\mu ^ + \) dà il prodotto scalare per varie rappresentazioni del gruppo conforme.
Реэюме
Покаэывается, что пространство представления конформной группыSO 4,2 представляет пространство Баргмана-Сегала когерентных состояний |w μ › для незрмитова оператора положения\(\bar w_\mu ^ + \). Состояния |w μ › являются когетентными в обычном смысле для минимальной неопределенностиx μ иp μ . Вешественная часть\(\bar w_\mu ^ + \), определяет зрмитов оператор положенияx μ Оба оператора удовлетворяют каноническим соотнощениям коммутации и являются ковариантными относительно конформной группы. Мнимая часть\(\bar w_\mu ^ + \) описывает дисперсию положения. Метрический операторG, свяэываюший\(\bar w_\mu \) с сопряженным\(\bar w_\mu ^ + \), определяет скалярное проиэведение для раэличных представлений конформной группы.
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Haba, Z. The four-dimensional position operator, coherent states and representations of the conformal group. Nuov Cim A 30, 567–588 (1975). https://doi.org/10.1007/BF02730487
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DOI: https://doi.org/10.1007/BF02730487