122 citations · 565 across the 14 of their papers we have counts for
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A solution of the strong CP problem via the Peccei-Quinn mechanism through the Nieh-Yan modified gravity and cosmological implications
Massimiliano Lattanzi, Simone Mercuri
By identifying the recently introduced Barbero-Immirzi field with the QCD axion, the strong CP problem can be solved through the Peccei-Quinn mechanism. A specific energy scale for…
A possible topological interpretation of the Barbero-Immirzi parameter
Simone Mercuri
A possible topological interpretation of the Barbero-Immirzi parameter is proposed. Classically, by generalizing the Holst action to torsional spacetimes, we construct a precise an…
Barbero-Immirzi field in canonical formalism of pure gravity
Gianluca Calcagni, Simone Mercuri
The Barbero-Immirzi (BI) parameter is promoted to a field and a canonical analysis is performed when it is coupled with a Nieh-Yan topological invariant. It is shown that, in the e…
Interaction of the Barbero--Immirzi Field with Matter and Pseudo-Scalar Perturbations
Simone Mercuri, Victor Taveras
In Loop Quantum Gravity the classical point of departure is the Einstein-Hilbert action modified by the addition of the so-called Holst term. Classically, this term does not affect…
Peccei--Quinn mechanism in gravity and the nature of the Barbero--Immirzi parameter
Simone Mercuri
A general argument provides the motivation to consider the Barbero--Immirzi parameter as a field. The specific form of the geometrical effective action allows to relate the value o…