VEV's and condensates from the Schr\"odinger Wave-functional

TL;DR

This paper presents a method to extract vacuum expectation values and condensates directly from the Schr"odinger wave-functional, enabling non-perturbative analysis of quantum field theories, demonstrated through (1+1)D models like the Schwinger model.

Contribution

It introduces a novel approach to study non-perturbative physics by deriving condensates from the wave-functional without additional calculations.

Findings

Successfully calculated fermion condensates in the Schwinger model.

Demonstrated the boundary reflection effect on the chiral condensate.

Provided a new perspective on non-perturbative phenomena in low-dimensional models.

Abstract

We show how VEV's and condensates can be read off from the Schr\"odinger wave-functional without further calculation. This allows us to study non-perturbative physics by solving the Schr\"odinger equation. To illustrate the method we calculate fermion condensates from the exact solution of the Schwinger model, and other (1+1) dimensional models. The chiral condensate is seen to be a large-distance effect due to propagators reflecting off the space-time boundary.