Theoretical cosmology in BP2

^{last updated: December 2014}

RESEARCH TOPICS

• Nature of cosmological singularity. 
• Spectrum of primordial gravitational radiation.
• Time issue in quantum cosmology 
• Coherent states in quantum cosmology 

WORKS PERFORMED IN 2014

• Dynamic system methods were applied to investigate mathematical structure of the Bianchi IX model phase space near cosmological singularity.
• The Bianchi II model was quantified in the context of applicability to quantify the most general model of that class (Bianchi IX).
• Quantum chaos in the Bianchi IX model was examined on a preliminary basis.
• Dynamics of homogenous and isotropic cosmologic models in the Brans-Dicki extended theory of gravitation was investigated. 
• It was checked whether any significant ambiguities in quantifying procedure might result from free choice of the so-called internal clock in physical description  of gravitational systems.
• Spectra of primary interferences within the loop quantum cosmology approach were determined.
• Coherent states were applied to describe semi-classic dynamics of cosmological models. 

THE MOST ESSENTIAL ACHIEVEMENTS (2014)

It was shown that:

• Dynamics of the Bianchi II model may be modelled as scattering of a particle on a potential barrier. 
• The Bianchi IX semi-classical model is not singular (classic singularity was replaced by quantum reflection).
• Quantized anisotropic degrees of freedom in the Bianchi XI model have the form of radiated quanta of energy of the gravitational field.
• Phase space in the Bianchi IX model contains some non-hyperbolic critical points, probably related to chaotic classical dynamics of that model.

The obtained results suggests that:

• Energetic levels in the quantum Bianchi IX model mutually repel, which is a typical feature of chaotic models.

APPLICABILITY OF THE OBTAINED RESULTS

• The obtained physical hamiltonian may be used to quantify the rather complicated general Bianchi IX system. 
• The results may be a starting point for further investigation on Bianchi-type models in the Brans-Dicki theory of gravitation. 
• Methods to quantify via coherent states helped to produce a scenario of evolution of the Universe without any singularity and to investigate the time issue. 
• It has been suggested that quantum correlation of the Universe may be responsible for cause-effect relations observed in the CMB spectrum (no need to resort to cosmological inflation). 
• The obtained interference spectra will help to confront theoretical predictions with experimentally observed CMB anisotropy and polarization.

RESEARCH TEAM

• Professor Włodzimierz Piechocki  
• Dr. Ewa Czuchry 
• Dr. Orest Hrycyna 
• Dr. Przemysław Malkiewicz
• Dr. Jakub Mielczarek

_{This page editoted by: Marek Pawłowski}