We prove a `Whitney' presentation, and a `Coulomb branch' presentation, for
the torus equivariant quantum K theory of the Grassmann manifold
Gr(k;n), inspired from physics, and stated in an earlier paper. The
first presentation is obtained by quantum deforming the product of the
Hirzebruch λy​ classes of the tautological bundles. In physics, the
λy​ classes appeared as certain Wilson line operators. The second
presentation is obtained from the Coulomb branch equations involving the
partial derivatives of a twisted superpotential from supersymmetric gauge
theory. This is closest to a presentation obtained by Gorbounov and Korff,
utilizing integrable systems techniques. Algebraically, we relate the Coulomb
and Whitney presentations utilizing transition matrices from the (equivariant)
Grothendieck polynomials to the (equivariant) complete homogeneous symmetric
polynomials. The calculations of K-theoretic Gromov-Witten invariants of wedge
powers of the tautological subbundles on the Grassmannian utilize the
`quantum=classical' statement.Comment: 39 page