Searcharxiv⌕ Search

arXiv subjects

Bartosz Grygielski

Publications and source records attributed to Bartosz Grygielski.

2 recordsLinked to original sources

Spin networks of quantum channels

Spin networks in Loop Quantum Gravity are traditionally described by unitary holonomies corresponding to noiseless transformations. In this work, we extend this framework to incorporate general quantum channels that model effects of environment, which can become significant at the Planck scale. Specifically, we demonstrate that the transformation properties of Kraus operators, which define completely positive trace-preserving (CPTP) maps, are consistent with the gauge invariance of spin networks. This enables the introduction of generalized spin network states that can be expressed in terms of the Kraus operators. Furthermore, the associated notion of an inner product is proposed, allowing for introduction of the Hilbert space. We illustrate these constructions with examples involving a Wilson loop and a dipole network.

gr-qc↗

Wilson line-based action for gluodynamics at the quantum level

We recently derived a new action for gluodynamics by canonically transforming the Yang-Mills action on light-cone. The transformation elimated triple gluons vertices and replaced the gauge fields with Wilson lines. This greatly reduced the number of diagrams required to compute tree level amplitudes. However, at the quantum level, the action turned out to be incomplete. We present two ways, based on one-loop effective action approach, to systematically develop quantum correction to our action. The first method retains Yang-Mills vertices in the loop, while the second method explicitly incorporates the interaction vertices of our action into the loop. We demonstrate that both approaches are equivalent, although the former appears to be more efficient for computing higher-multiplicity one-loop amplitudes.

hep-th↗