activity
20242026
collaborators

10 papers

hep-th2026

Quantum mechanics with a ghost: Counterexamples to spectral denseness

Cédric Deffayet, Atabak Fathe Jalali, Aaron Held +2

We quantise integrable point-particle systems with opposite-sign kinetic terms and nontrivial interactions. Using methods from separability theory, we show that previously determin…

hep-th2026

Unitary Time Evolution and Vacuum for a Quantum Stable Ghost

Cédric Deffayet, Atabak Fathe Jalali, Aaron Held +2

We quantize a classically stable system of a harmonic oscillator polynomially coupled to a ghost with negative kinetic energy. We prove that due to an integral of motion with a pos…

gr-qc2026

The emergent Big Bang scenario

Justin C. Feng, Shinji Mukohyama, Jean-Philippe Uzan

This paper proposes a new avenue for understanding the cosmological singularity. The standard cosmological model contains a generic initial singularity usually referred to as the {…

gr-qc2025

Emergent Lorentzian dispersion relations from a Euclidean scalar-tensor theory

Justin C. Feng, Shinji Mukohyama, Sante Carloni

Can one be fooled into thinking that space and time are fundamentally described by a Lorentzian manifold? In this article, we describe a scenario in which a theory constructed on a…

gr-qc2025

HBT Interferometry and Quantum Nature of Primordial Gravitational Waves in Hořava-Lifshitz Gravity

Sugumi Kanno, Hiroki Matsui, Shinji Mukohyama

Hořava-Lifshitz gravity (to be precise, its projectable version) is recognized as a renormalizable, unitary, and asymptotically free quantum field theory of gravity. Notably, one…

gr-qc2025

Anisotropic quantum universe in Hořava-Lifshitz gravity

Vikramaditya Mondal, Shinji Mukohyama

We quantize a Bianchi IX universe in Hořava-Lifshitz theory. For analytical tractability, we consider the small anisotropy limit of the Bianchi IX, that is, a perturbative anisotr…