Location
MC 5501
Candidate
Sukanya Ghosal | Applied Mathematics, University of Waterloo
Title
Exploring Novel Phenomena behind the Non-additivity of Quantum Capacity
Abstract
In contrast to Classical Shannon theory, where classical correlations between the inputs of two classical channels do not increase their overall capacity, the determination of quantum channel capacities is significantly more complex. This challenge arises from the super-additive effects of the capacities of a quantum channel, which stem from the ability to exploit entanglement across channel inputs to enhance communication. When dynamic information measures lack additivity, interpreting a given measure becomes challenging, as it would require evaluating the measure across infinitely many independent uses of the channel, making optimization infeasible. As a result, investigating the non-additivity of channel capacities remains a key area of research in quantum Shannon theory. Exploring the form of the entanglement that enhances the quantum capacity of the tensor product of channels is essential in understanding the most optimal coding strategies. This research revolves around understanding the underlying phenomena behind the plethora of super-additivity effects like the amplification and the super-amplification of quantum capacity using a family of channels, called the “platypus channels". During the PhD, we aim at (1) exploring the capacities of the class of covariant channels that are constructed from the representation theory of compact topological groups with nice algebraic structure, (2) investigating the possibility/impossibility of achieving additive entropic quantities in finite dimensions that quantify channel capacity, and (3) extend the study to predict the best coding strategies beyond point-to-point communication with multiple access and broadcast channels, especially, with the quantum channels with certain symmetries.
Location Information
200 University Avenue West
Waterloo, ON, CA N2L 3G1
