Signatures of Quantum Gravity In Relativistic Quantum Systems

TL;DR

This thesis explores quantum gravity effects on matter systems using linearized quantum gravity, proposing detector models to identify graviton signatures and analyzing phenomenological implications like memory effects and decoherence.

Contribution

It introduces new detector models for graviton detection and investigates quantum gravity induced phenomena in relativistic quantum systems.

Findings

Hints at quantum gravity induced memory effects

Derived a quantum gravity modified uncertainty relation

Proposed a graviton detector based on BEC decoherence

Abstract

In this thesis, we have used a linearized quantum gravity setting to investigate the effects of gravitons on matter systems. Based on the graviton-matter interaction, we have then proposed detector models that may be able to pick up graviton-induced signatures in a matter of a few years. We start with the simple model of a two-particle model detector system interacting with quantized gravitational fluctuations while the detector degrees of freedom obey the generalized uncertainty principle (GUP). For the first part we have hinted at the existence of quantum gravity induced memory effect as well as obtained a quantum gravity modified uncertainty relation. For the next part of the thesis, we have mainly focused on the phenomenological aspects of a linearized quantum gravity theory. For the initial phenomenological model, we have considered the same two-particle model detector system interacting with gravitational fluctuations where the entire set-up is placed inside a harmonic trap potential and looked at the stimulated absorption and spontaneous emission scenario for gravitons. In order to inspect a more involved phenomenological aspect, instead of the standard matter-detector system, we make use of a relativistic scalar Bose-Einstein condensate (BEC) and investigated the response of the BEC based model towards incoming gravitons and proposed a graviton detector based on graviton mediated decoherence from entangled BECs.