We construct integrals of motion (IM) for the sine-Gordon model with boundary at the free fermion point (β2 = 4π) which correctly determine the boundary S matrix. The algebra of these IM ("boundary quantum group" at q = 1) is a one-parameter family of infinite-dimensional subalgebras of twisted sl(2). We also propose the structure of the fractional-spin IM away from the free fermion point (β2 ≠ 4π).
ASJC Scopus subject areas
- Atomic and Molecular Physics, and Optics
- Nuclear and High Energy Physics
- Astronomy and Astrophysics