Canonical transformations and graph theory

Graph Polynomials and Graph Transformations in Algebraic Graph Theory

The thesis consists of two parts. In the first part we study two graph transformations,namely the Kelmans transformation and the generalized tree shift. In the second part of thisthesis we study an extremal graph theoretic problem and its relationship with algebraic graphtheory. The main results of this thesis are the following. • We show that the Kelmans transformation is a very ef...

Canonical transformations theory for presymplectic systems

On Normal Ordering and Canonical Transformations in Thermal Field Theory

We look at a real scalar field in thermal equilibrium in the context of the new normal ordering and field split defined by Evans and Steer [1]. We show that the field split defines a natural canonical transformation, but that this transformation differs from others known in thermal field theory.

Ultracoherence and Canonical Transformations

Canonical transformations are studied in the bosonic Fock space using coherent and ultracoherent vectors. The connection between the Weyl operator and the homogeneous canonical transformations (Bogoliubov transformations) is presented. The unitary ray representation of the symplectic group is defined in the bosonic Fock space by the action of the group on the ultracoherent vectors.

Duality and Canonical Transformations

We present a brief review on the canonical transformation description of some duality symmetries in string and gauge theories. In particular, we consider abelian and non-abelian T-dualities in closed and open string theories as well as S-duality in abelian and non-abelian non-supersymmetric gauge theories. THU-96/36 hep-th/9610024 October 1996 Talk given at the Argonne Duality Institute, June 2...