The Dissipative Quantum Rotator will be discussed within a framework of Caldeira-Leggett approach. The model is commonly used to describe a quantum dot which is connected to the bulk via a large number of tunneling channels. It can be also reformulated as a 2D QFT with boundary interaction, in which a two component massless Bose field in constrained to a circle at the boundary. We shall review recent exact results (hep-th/0306188, 0501155) concerning the model.

Rutgers