A NonStandard Cosmological Model
Abstract
A nonstandard cosmological model in WeylCartan spacetime was presented^{1}. Within this model the nonRiemannian quantities, i.e. torsion T^{α} and nonmetricity Q_{αβ}, are proportional to the Weyl 1form. The hypermomentum ∆_{αβ} depends on our ansatz for the nonmetricity and vice versa. In contrast to earlier investigations^{2} this model incorporates an additional quadratic nonmetricity term in the gauge Lagrangian, the Lagrangian under consideration reads <DF> <TEX ID="S0217751X02011990E001">$$\begin{equation} V_{\rm gauge} = \frac{\chi}{2\kappa} R_\alpha {}^\beta \wedge \eta_\beta {}^\alpha + \sum_{I=1}^6 a_I {}^{(I)} W_\alpha {}^\beta \wedge {}^* R_\beta {}^\alpha\\ + b Z_{\alpha\beta} \wedge {}^* R^{\beta\alpha} + \sum_{I=1}^4 c_I {}^{(I)} Q_{\alpha\beta} \wedge {}^* Q^{\beta\alpha}\,.\end{equation}$$ </TEX> </DF> We derived the explicit form of the field equations for different cases and provided solutions for a broad class of parameters. It was demonstrated that it is possible to construct models in which the nonRiemannian quantities die out with time. We showed how our model fits into the more general framework of metricaffine gravity (MAG)^{3}. Additionally, we presented some preliminary results from our search for the bestfit parameters^{4} which was performed by using recent type Ia supernova data^{5}.
 Publication:

International Journal of Modern Physics A
 Pub Date:
 2002
 DOI:
 10.1142/S0217751X02011990
 Bibcode:
 2002IJMPA..17.2772P