UNITARITY AND THE EVALUATION OF DISCONTINUITIES. PART II

Journal Article · Tue Jul 16 04:00:00 EDT 1963 · Nuovo Cimento (Italy) Divided into Nuovo Cimento A and Nuovo Cimento B

OSTI ID:4683478

Olive, D I

The discontinuity across the cut due to the normal threshold N in the scattering amplitude is found to be a modification of the term in unitarity involving the state N. The result shows that it is easiest to continue onto the unphysical sheet reached by encircling the normal threshold in an anticlockwise direction and enables unitarity to be replaced by a system of simpler equations. The result is understood in perturbation theory and is presented in terms of a specially introduced path notation for unphysical sheets. Although the argument is mainly restricted to twoparticle thresholds, it permits the analytic continuation round the lowest three-particle cut. The difficulties in extending the analysis to multiparticle processes are reviewed. (auth)

• Research Organization: Cambridge Univ., Eng.
• NSA Number: NSA-17-042168
• OSTI ID: 4683478
• Journal Information: Nuovo Cimento (Italy) Divided into Nuovo Cimento A and Nuovo Cimento B, Journal Name: Nuovo Cimento (Italy) Divided into Nuovo Cimento A and Nuovo Cimento B Vol. Vol: (10), 29; ISSN NUCIA
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

EQUATIONS
INTERACTIONS
MATHEMATICS
PARTICLES
PERTURBATION THEORY
PHYSICS
SCATTERING
SCATTERING AMPLITUDE
SHEETS
UNITARITY