Immirzi Ambiguity, Boosts and Conformal Frames for Black Holes

TL;DR

This paper explores how the Immirzi parameter, Lorentz boosts, and conformal transformations influence black hole physics in loop quantum gravity, revealing ambiguities in black hole entropy related to frame choices.

Contribution

It demonstrates the analogy between the Immirzi ambiguity and conformal or Lorentz frame choices in black hole entropy calculations.

Findings

Effective Planck length depends on conformal or Lorentz frame.

Black hole entropy ambiguity is similar to Immirzi parameter effects.

Implications for energy-related quantities differ from entropy considerations.

Abstract

We analyze changes of the Immirzi parameter in loop quantum gravity and compare their consequences with those of Lorentz boosts and constant conformal transformations in black hole physics. We show that the effective value deduced for the Planck length in local measurements of vacuum black holes by an asymptotic observer may depend on its conformal or Lorentz frame. This introduces an apparent ambiguity in the expression of the black hole entropy which is analogous to that produced by the Immirzi parameter. For quantities involving a notion of energy, the similarity between the implications of the Immirzi ambiguity and a conformal scaling disappears, but the parallelism with boosts is maintained.