The dark side of the torsion: dark energy from propagating torsion
David Benisty, Eduardo Guendelman, Armin van de Venn, David Vasak, Jürgen Struckmeier, Horst Stoecker
Abstract
Abstract An extension to the Einstein–Cartan (EC) action is discussed in terms of cosmological solutions. The torsion incorporated in the EC Lagrangian is assumed to be totally anti-symmetric, represented by a time-like axial vector $$S^\mu $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msup> <mml:mi>S</mml:mi> <mml:mi>μ</mml:mi> </mml:msup> </mml:math> . The dynamics of torsion is invoked by a novel kinetic term. Here we show that this kinetic term gives rise to dark energy, while the quadratic torsion term, emanating from the EC part, represents a stiff fluid that leads to a bouncing cosmology solution. A constraint on the bouncing solution is calculated using cosmological data from different epochs.