20–23 Oct 2026
University of Tarapacá-Arica
America/Santiago timezone

Discrete teleparallel quantum cosmology

Not scheduled
15m
To be announced (University of Tarapacá-Arica)

To be announced

University of Tarapacá-Arica

Av. General Velásquez 1775, Arica, Chile

Speaker

Rudranil Roy (Universidad de Tarapacá)

Description

I will present a unified discrete quantum cosmological framework based on the Teleparallel Equivalent of General Relativity (TEGR). By formulating gravity strictly as a gauge theory of the non-compact translation group $T(4)$, we map the continuous Weitzenböck geometry onto a simplicial Regge lattice, where spacetime torsion manifests physically as localized structural dislocations quantified by the discrete Burgers vector $b_d$. In a homogeneous and isotropic Friedmann-Robertson-Walker (FRW) minisuperspace, coarse-graining over the extensive macroscopic area $\Sigma = \sum_{\text{dis}} \Sigma_d$ and the collective translational defect $b = \sum_{\text{dis}} b_d$ demonstrates that the Burgers vector acts as the exact canonical conjugate momentum to the spatial area, $b = -24\pi G P_\Sigma$. We then establish the quantum gravitational dynamics across two complementary regimes. First, applying polymer quantization (Bohr compactification) to regularize the non-compact translational momentum via finite-difference shift operators introduces a trigonometric holonomy correction, yielding a bounded effective Friedmann equation, $H^2 = \frac{8\pi G}{3}\rho\left(1 - \frac{\rho}{\rho_c}\right)$, that averts the classical singularity at a critical density $\rho_c$. Second, in canonical quantization, the discrete finite-difference Wheeler-DeWitt equation enforces global background stationarity ($\langle \hat{H}^2 \rangle_{\text{global}} = 0$), motivating a statistical decomposition of the macroscopic FRW state into a tensor product of localized simplicial Hilbert spaces, $\mathcal{H}_{\text{tot}} = \bigotimes_{d=1}^N \mathcal{H}_d$. Evaluating the local partition function over zero-point torsion fluctuations reveals that while the mean linear defect vanishes, the local squared variance remains strictly positive. At the ultraviolet (UV) minimal area scale $l_0^2$, this variance drives a finite maximum expansion rate $H_{BB}^2 = \frac{8\pi G}{\gamma l_0^4}$ at the Quantum Bounce. Integrating the thermalized ensemble over all accessible cell scales up to the late-time infrared (IR) causal horizon $L \sim R_H$ dynamically suppresses this primordial bounce rate by the squared UV-to-IR cutoff ratio, $\langle H_d^2 \rangle_{\text{today}} = H_{BB}^2 (l_0 / L)^2 \sim 10^{-122} H_{BB}^2 \approx \Lambda / 3$. Consequently, the observed cosmological constant emerges natively—not from an ad hoc scalar potential, but as the residual macroscopic ensemble variance of discrete quantum teleparallel fluctuations.

Author

Rudranil Roy (Universidad de Tarapacá)

Presentation materials

There are no materials yet.