May 26 – 31, 2024
Western University
America/Toronto timezone
Welcome to the 2024 CAP Congress Program website! / Bienvenue au siteweb du programme du Congrès de l'ACP 2024!

A Quantum Spacetime Route to Quantum Gravity

May 31, 2024, 11:15 AM
15m
SSC Rm 2028 (cap. 135) (Social Science Centre, Western U.)

SSC Rm 2028 (cap. 135)

Social Science Centre, Western U.

Oral (Non-Student) / Orale (non-étudiant(e)) Theoretical Physics / Physique théorique (DTP-DPT) (DTP) F2-2 Classical and Quantum Gravity | Gravité classique et quantique (DPT)

Speaker

Prof. Jonathan Sharp (University of Alberta)

Description

Approach: Although quantum field theories (QFTs) represent a powerful formalism, there is no guarantee that any given QFT proposal will apply to our particular universe. Although a QFT framework has many benefits, by itself, it nevertheless offers a speculative road to quantum gravity. By contrast, here I describe an alternative ontology-driven approach which prioritizes defining an ontology consistent with existing theory. The situation is reversed vis-à-vis QFT: the mathematical machinery is distinctly primitive, whereas the physical motivation and connection to existing theory potentially much stronger.

Proposal: I will describe an approach to quantum spacetime originating in an effort to reconcile the multiple conflicting viewpoints of an ensemble of inertial observers. Exploiting the space-time symmetry of the Lorentz boost, a multi-space, single-universe ontology arises. This relativistic spacetime ontology in turn exhibits striking quantum-like properties, but still within a fully classical setting. It then becomes possible to map classical relativistic features onto quantum behaviours to arrive at an integrated quantum spacetime. The result is specific spacetime support for quantum phenomena including superposition, indeterminacy and nonlocality. The spacetime roots of this approach leads to a specific spacetime mechanism for quantum superposition, which, by postulate, is the fundamental basis (reducing to momentum superposition in simpler cases).

Quantum Gravity: The claim is that an understanding of quantum spacetime is a necessary pre-requisite for quantum gravity, in parallel with the manner SR underpins GR. How does this proposal relate to other QG approaches? This proposal features: strong physical motivation; no Lorentz violations; a strong relational character; a spacetime superposition principle operating within a single universe. This QG groundwork is experimentally testable because the emergence of quantum behaviours from flat spacetime directly addresses the measurement problem. Since this proposal is agnostic on Planck-scale discrete structure, it would be of definite interest to investigate potential compatibility with other QG approaches.

For further details: https://orcid.org/0000-0002-9736-7487

Keyword-1 Quantum Gravity
Keyword-2 Quantum Spacetime

Author

Prof. Jonathan Sharp (University of Alberta)

Presentation materials

There are no materials yet.