Lee's Fest: Quantum Gravity and the Nature of Time

Session

Poster Session

Jun 6, 2025, 2:00 PM

PI/1-119 - Atrium (Perimeter Institute for Theoretical Physics)

1. Complexity, scaling, and a phase transition

Jiayue Yang

6/6/25, 2:00 PM

Poster

We investigate the holographic complexity of CFTs compactified
on a circle with a Wilson line, dual to magnetized solitons in AdS$_4$ and
AdS$_5$. These theories have a confinement-deconfinement phase transition
as a function of the Wilson line, and the complexity of formation acts as
an order parameter for this transition. Through explicit calculation,
we show that proposed complexity...

6. The Surrational Materialism of the Path Integral

Esterina Celami (PhD researcher)

6/6/25, 2:05 PM

Poster

In recent debates on the ontology of quantum mechanics, Slavoj Žižek suggests that the Feynman path integral entails a subtle backward in time element, aligning this claim with his broader philosophical framework, which emphasizes symbolic mediation and retroactive causality . Žižek’s interpretation portrays the path integral as fundamentally indifferent to the direction of time, situating...

7. Origins of Thermalization in Quantum Cosmology

Michael Osei (University of Lethbridge)

6/6/25, 2:10 PM

Poster

We investigate how accelerated frames influence the cosmic evolution of a semi-classical universe
and propose that these effects can lead to thermalization at the quantum cosmological level. Our
primary research question is whether transformations in super-space, the configuration space of
the gravitational field can yield a mixed (and thus thermal) density matrix for the universe.
To...

48. Shocks but not cataclysms: continuous dynamical extension beyond shell crossings

Hassan Mehmood (University of New Brunswick)

6/6/25, 2:15 PM

Poster

During the gravitational collapse of pressureless fluids in spherical symmetry, matter particles may collide with each other, forming what are called shell crossing surfaces. The differential equations governing the system become indeterministic at these surfaces, beyond which, therefore, the evolution of matter has to be determined by some other mechanism. This can be done by writing the...

49. Hydrogenic entanglement as a test for ER = EPR

Irfan Javed (University of New Brunswick)

6/6/25, 2:20 PM

Poster

The ER = EPR conjecture states that entangled particles are connected by microscopic worm holes. We look at some potential consequences of this "worm-hole-mediated entanglement." In particular, we see how they ought to affect the spectra of some well-known quantum systems in physics, such as the Hydrogen atom. Since the effects are significant but not observed experimentally, we are lead to...

50. Semiclassical static solutions in spherically symmetric gravity

Irfan Javed (University of New Brunswick)

6/6/25, 2:25 PM

Poster

We use the Hamiltonian version of the semiclassical Einstein equation to study gravity coupled to a real scalar field. Starting from the full Einstein-Klein-Gordon system, we restrict to the spherically symmetric sector and derive the phase space equations of motion. In the semiclassical regime, we could do away with the scalar field equations and replace the scalar field variables by their...

51. Semiclassical Mixmaster Universe

Muhammad Muzammil (University of New Brunswick)

6/6/25, 2:40 PM

Poster

We present a semiclassical study of the Mixmaster cosmology minimally coupled to a massive scalar field in the Hamiltonian formalism, with focus on three distinct scenarios: the classical cosmology coupled to the quantized scalar field, and "effective" cosmology, with spacetime discreteness corrections, coupled to the classical scalar field, and to the quantized scalar field. We find several...

57. The Local Many Worlds Interpretation and Quantum Gravity

Mordecai Waegell (Institute for Quantum Studies, Chapman University)

6/6/25, 2:55 PM

Poster

The Local Many Worlds Interpretation (LMWI) of quantum mechanics, unlike the Everett Many Worlds interpretation, is an entirely separable Lorentz covariant theory in spacetime. LMWI explains observed violations of Bell inequalities using a straightforward locally causal mechanism, which requires multiple local worlds for each observer. An extension of this model to treat gravity works by...

59. When Nothing Ticked: Physical and Geometrical Time in Early-Universe Cosmology

Asya Ciftci (McGill University)

6/6/25, 3:10 PM

Poster

The notion of time arises in two fundamentally distinct frameworks: physical time, grounded in operational standards such as atomic transitions or electromagnetic oscillations, and geometrical time, typically defined through coordinate choices and metric structures. This distinction becomes particularly problematic in the early universe, where traditional physical clocks—based on stable,...