Recently representations over non–commutative rings were used by Cochran, Harvey, Friedl–Kim and Turaev to define Alexander polynomials whose degrees give lower bounds on the Thurston norm. We first show how Reidemeister torsion relates to these invariants. We give lower bounds on the Thurston norm in terms of the Reidemeister torsion which contain all the above lower bounds and give an elegant...

Recently twisted and higher order Alexander polynomials were used by Cochran, Harvey, Friedl–Kim and Turaev to give lower bounds on the Thurston norm. We first show how Reidemeister torsion relates to these Alexander polynomials. We then give lower bounds on the Thurston norm in terms of the Reidemeister torsion which contain and extend all the above lower bounds and give an elegant reformulati...