[Paper Review] Connecting Quantum and Cosmic Scales by a Decreasing-Light-Speed Model

Juan Casado|arXiv (Cornell University)|Apr 6, 2004

Cosmology and Gravitation Theories3 citations

TL;DR

This paper proposes a cosmological model in which the speed of light decreases over time, linking quantum and cosmic scales by relating the observable Universe's radius, age, and mass to Planck units. The model implies that Planck length and time increase while Planck mass remains constant, resolving quantum-gravity conflicts in the early universe and yielding a constant entropy for the cosmic event horizon.

ABSTRACT

In this paper we point out that the radius R, the age t and the mass M of the observable Universe are proportional to Planck units for length lp, time tp and mass mp.This hypothesis is related, by a cosmological model linking the universal expansion to the speed of light, with a time variation of c and of the Planck constant, which implies that lp and tp increase with time while mp remains constant. We discuss some of the implications these relationships could have on quantum cosmology and obtain that the Universe entropy associated to the event horizon is constant along its history. Quantum effects were smaller in the past, in such a way that their conflict with general relativity about the Planck era vanishes.

Motivation & Objective

• To reconcile quantum mechanics and general relativity by introducing a time-varying speed of light.
• To explain the observed scale of the observable Universe (radius, age, mass) in terms of Planck units.
• To resolve the conflict between quantum effects and general relativity in the Planck era.
• To explore implications for quantum cosmology and the thermodynamics of the universe.
• To demonstrate that the entropy of the cosmic event horizon remains constant throughout cosmic history.

Proposed method

• Proposes a cosmological model where the speed of light c decreases over time, linked to the expansion of the universe.
• Derives relationships between the observable Universe's radius R, age t, and mass M and Planck units (lp, tp, mp).
• Assumes Planck length lp and Planck time tp increase with time, while Planck mass mp remains constant.
• Uses the time variation of c and h (Planck constant) to derive the scaling of fundamental units.
• Applies the model to compute the entropy of the cosmic event horizon and shows it remains constant.
• Analyzes the implications for quantum effects in the early universe, showing they were smaller in the past.

Experimental results

Research questions

• RQ1 How can the observable Universe's parameters (R, t, M) be related to Planck units in a consistent cosmological framework?
• RQ2 What are the consequences of a decreasing speed of light on the evolution of fundamental constants?
• RQ3 How does a time-varying c affect the unification of quantum mechanics and general relativity?
• RQ4 What is the behavior of the entropy associated with the cosmic event horizon under this model?
• RQ5 Why were quantum effects less significant in the early universe under this decreasing-c scenario?

Key findings

• The radius R, age t, and mass M of the observable Universe are proportional to the Planck length lp, Planck time tp, and Planck mass mp, respectively.
• The model implies that Planck length and time increase with cosmic time, while Planck mass remains constant.
• The entropy of the cosmic event horizon is constant throughout the history of the universe.
• Quantum effects were smaller in the past due to the decreasing speed of light, resolving the conflict with general relativity in the Planck era.
• The time variation of c and h leads to a consistent scaling of fundamental units across cosmic evolution.
• The model provides a mechanism for unifying quantum and cosmic scales through a dynamic light speed.