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 (34)
- Echoes of a Hidden Valley at Hadron Colliders
- Quantum Gravity and Extra Dimensions at High-Energy Colliders
- Unparticle Physics
- Holography and Phenomenology
- Comments on the Holographic Picture of the Randall-Sundrum Model
- A Clockwork Axion
- Oscillations of neutrinos and mesons in quantum field theory
- Quantum equilibration in finite time
- A Clockwork Theory
- Randall-Sundrum models and the regularized AdS/CFT correspondence
- Deconstruction of Unparticles
- Electroweak Breaking on a Soft Wall
- Little String Theory at a TeV
- Invisible Axions and Large-Radius Compactifications
- The AdS/CFT/Unparticle Correspondence
- Colored Unparticles
- Neutrino oscillations: Entanglement, energy-momentum conservation and QFT
- Combining searches of Z' and W' bosons
- Holographic Unhiggs
- Nearby resonances beyond the Breit-Wigner approximation
- HEIDI and the unparticle
- The Unhiggs
- Continuum Naturalness
- Gapped Continuum Kaluza-Klein spectrum
- On Continuum Effective Field Theories, Gravity and Holography
- The Continuum Linear Dilaton
- Cosmological Dark Matter from a Bulk Black Hole
- A Note on Unparticle Decays
- On the Decay of Unparticles
- Electroweak Precision Observables and the Unhiggs
- Z-portal Continuum Dark Matter
- Unparticle signals with a few particles
- Equilibration times in clean and noisy systems
- The Continuum Dark Matter Zoo