Undecay
arXiv:2310.16593 · doi:10.1007/JHEP05(2024)158
Abstract
Unstable particles decay sooner or later, so they are not described by asymptotic one-particle states and they should not be included as independent states in unitarity relations such as the optical theorem. The same applies to any countable collection of unstable particles. We show that the behaviour of unparticle stuff, that is, a continuous collection of particles with different masses and common decay channels, is pretty different: it has a non-vanishing probability of surviving for ever and the corresponding asymptotic states must be taken into account to comply with unitarity. We also discuss compressed spectra and the transition from the discrete to the continuous case.
55 pages, 16 figures, new summary section, improved discussion, references added
References in corpus (15)
- Echoes of a Hidden Valley at Hadron Colliders
- Unparticle Physics
- A Clockwork Theory
- Deconstruction of Unparticles
- Electroweak Breaking on a Soft Wall
- Colored Unparticles
- Neutrino oscillations: Entanglement, energy-momentum conservation and QFT
- HEIDI and the unparticle
- On Continuum Effective Field Theories, Gravity and Holography
- The Continuum Linear Dilaton
- Cosmological Dark Matter from a Bulk Black Hole
- On the Decay of Unparticles
- Z-portal Continuum Dark Matter
- Equilibration times in clean and noisy systems
- The Continuum Dark Matter Zoo