Negative reflection coefficients

Generalized Reflection Coefficients

I consider general reflection coefficients for arbitrary one-dimensional whole line differential or difference operators of order 2. These reflection coefficients are semicontinuous functions of the operator: their absolute value can only go down when limits are taken. This implies a corresponding semicontinuity result for the absolutely continuous spectrum, which applies to a very large class ...

Littlewood–Richardson coefficients for reflection groups

Article history: Received 21 June 2012 Received in revised form 7 June 2015 Accepted 23 July 2015 Available online xxxx Communicated by Roman Bezrukavnikov

Polynomial Interpretations with Negative Coefficients

Polynomial interpretations are a useful technique for proving termination of term rewrite systems. We show how polynomial interpretations with negative coefficients, like x− 1 for a unary function symbol or x− y for a binary function symbol, can be used to extend the class of rewrite systems that can be automatically proved terminating.

Negative Reflection in a Faraday Chiral Medium

The four wavenumbers associated with planewave propagation in a Faraday chiral medium (FCM) with relatively huge magnetoelectric coupling give rise to enhanced possibilities for negative–phase–velocity propagation and therefore negative refraction. They can also give rise to the phenomenon of negative reflection. In particular, for a nondissipative example, we deduced that an incident plane wav...

Reflection and absorption coefficients for use in room acoustic simulations