Cluster Truncated Wigner Approximation in Strongly Interacting Systems

Understand

We present a general method by which linear quantum Hamiltonian dynamics with exponentially many degrees of freedom is replaced by approximate classical nonlinear dynamics with the number of degrees of freedom (phase space dimensionality) scaling polynomially in the system size.

• This method is based on generalization of the truncated Wigner approximation (TWA) to a higher dimensional phase space, where phase space variables are associated with a complete set of quantum operators spanning finite size clusters.
• The method becomes asymptotically exact with the increasing cluster size.
• The crucial feature of TWA is fluctuating initial conditions, which we approximate by a Gaussian distribution.