Galois Theory of Difference Equations with Periodic Parameters

Benjamin Antieau, Alexey Ovchinnikov, Dmitry Trushin
2014 Communications in Algebra  
We develop a Galois theory for systems of linear difference equations with periodic parameters, for which we also introduce linear difference algebraic groups. We then apply this to constructively test if solutions of linear q-difference equations, with complex q, not a root of unity, satisfy any polynomial q'-difference equations with q' being a root of unity.
doi:10.1080/00927872.2013.797991 fatcat:7oj4ampmrnbf5dqqrhqcuzzeru