PIRSA:19010072

Quantum Tasks in Relativistic Spacetime

Adlam, E. (2019). Quantum Tasks in Relativistic Spacetime. Perimeter Institute. https://pirsa.org/19010072

Adlam, Emily. Quantum Tasks in Relativistic Spacetime. Perimeter Institute, Feb. 04, 2019, https://pirsa.org/19010072 

          @misc{ pirsa_PIRSA:19010072,
            doi = {10.48660/19010072},
            url = {https://pirsa.org/19010072},
            author = {Adlam, Emily},
            keywords = {Quantum Foundations},
            language = {en},
            title = {Quantum Tasks in Relativistic Spacetime},
            publisher = {Perimeter Institute},
            year = {2019},
            month = {feb},
            note = {PIRSA:19010072 see, \url{https://pirsa.org}}
          }

Emily Adlam

Chapman University

Talk number
PIRSA:19010072
Collection
Talk Type
Subject
Abstract

In this talk I will set out two new contributions to the study of operational tasks in a relativistic quantum setting. First, I will present a generalisation of the task known as ‘summoning,’ in which an unknown quantum state is supplied to an agent and must be returned at a specified point when a corresponding call is made. I will show that when this task is generalised to allow for more than one call to be made, an apparent paradox arises: the extra freedom makes it strictly harder to complete the task. Second, I will describe a quantum generalisation of the classic cryptographic task known as ‘zero-knowledge-proving.’ I will show that there exists no perfectly secure quantum relativistic protocol for this task, and I will then set out a protocol which is conjectured to be close to optimal in security for this task. These results have practical applications for distributed quantum computing and cryptography and also interesting implications for our understanding of relativistic quantum information and its localisation in spacetime.