Linear Quantum Transformation Theory of Multi-Mode Bosons and Its Application to Calculation of Partition Function
Sixia Yu, Yong-De Zhang · Communications in Theoretical Physics · 1995
In this paper, we present a linear quantum transformation theory in the -mode boson Fock space, and give a formula that shows how a transformation operator changes its exponential form to its normal ordered form. As an application we evaluate the partition function of a general quadratic system without any information of the energy levels of the system by using our transformation theory.