Comparison of the semiclassical and quantum dynamics of the Bianchi I cosmology in the polymer and GUP extended paradigms

• DOI: 10.1142/s0219887822500979
• Publication Date: 2022-02-21T13:57:58Z
• Authors: Gabriele Barca; Eleonora Giovannetti; Giovanni Montani
• Keywords: Semiclassical physics; Loop Quantum Cosmology

We compare in some detail Polymer Quantum Mechanics and the Generalized Uncertainty Principle approach to clarify what extent we can treat them on same footing. show that, while a semiclassical level they may be formulated as similar modifications of Poisson algebra, quantum intrinsically differ because PQM implies no absolute minimal uncertainty position. Then implement these schemes Bianchi I cosmology deforming only algebra Universe volume, searching for alternative formulations able account modified Friedmann equations emerging Brane Cosmology Loop Cosmology. On pure level, two approaches through their original setups reduce resulting Wheeler-DeWitt morphological structure, showing how polymer formalism is associated with bouncing dynamics case singularity still present. The implications wavepacket spreading are also discussed both approaches, outlining when survives, Planckian era must necessarily approached by fully (non-peaked) state Universe.