83 citations · 414 across the 29 of their papers we have counts for
31 papers
Breaking barriers in two-party quantum cryptography via stochastic semidefinite programming
Akshay Bansal, Jamie Sikora
In the last two decades, there has been much effort in finding secure protocols for two-party cryptographic tasks. It has since been discovered that even with quantum mechanics, ma…
A note on the inner products of pure states and their antidistinguishability
Vincent Russo, Jamie Sikora
A set of d quantum states is said to be antidistinguishable if there exists a d-outcome POVM that can perfectly identify which state was not measured. A conjecture by Havlíček and…
Simulating all multipartite non-signalling channels via quasiprobabilistic mixtures of local channels in generalised probabilistic theories
Paulo J. Cavalcanti, John H. Selby, Jamie Sikora +1
Non-signalling quantum channels -- relevant in, e.g., the study of Bell and Einstein-Podolsky-Rosen scenarios -- may be simulated via affine combinations of local operations in bip…
A constant lower bound for any quantum protocol for secure function evaluation
Sarah Osborn, Jamie Sikora
Secure function evaluation is a two-party cryptographic primitive where Bob computes a function of Alice's and his respective inputs, and both hope to keep their inputs private fro…
Completely positive completely positive maps (and a resource theory for non-negativity of quantum amplitudes)
Nathaniel Johnston, Jamie Sikora
In this work we examine quantum states which have non-negative amplitudes (in a fixed basis) and the channels which preserve them. These states include the ground states of stoquas…
Post-quantum steering is a stronger-than-quantum resource for information processing
Paulo J. Cavalcanti, John H. Selby, Jamie Sikora +2
We present the first instance where post-quantum steering is a stronger-than-quantum resource for information processing -- remote state preparation. In addition, we show that the…
Jordan products of quantum channels and their compatibility
Mark Girard, Martin Plávala, Jamie Sikora
Given two quantum channels, we examine the task of determining whether they are compatible - meaning that one can perform both channels simultaneously but, in the future, choose ex…
A fidelity measure for quantum states based on the matrix geometric mean
Sam Cree, Jamie Sikora
Uhlmann's fidelity function is one of the most widely used similarity measures in quantum theory. One definition of this function is that it is the minimum classical fidelity assoc…
A device-independent protocol for XOR oblivious transfer
Srijita Kundu, Jamie Sikora, Ernest Y. -Z. Tan
Oblivious transfer is a cryptographic primitive where Alice has two bits and Bob wishes to learn some function of them. Ideally, Alice should not learn Bob's desired function choic…
Fundamental limitations to local energy extraction in quantum systems
Álvaro M. Alhambra, Georgios Styliaris, Nayeli A. Rodriguez-Briones +2
We examine when it is possible to locally extract energy from a bipartite quantum system in the presence of strong coupling and entanglement, a task which is expected to be restric…
On the impossibility of coin-flipping in generalized probabilistic theories via discretizations of semi-infinite programs
Jamie Sikora, John H. Selby
Coin-flipping is a fundamental cryptographic task where a spatially separated Alice and Bob wish to generate a fair coin-flip over a communication channel. It is known that ideal c…
Quantum generalizations of the polynomial hierarchy with applications to QMA(2)
Sevag Gharibian, Miklos Santha, Jamie Sikora +2
The polynomial-time hierarchy () has proven to be a powerful tool for providing separations in computational complexity theory (modulo standard conjectures such as $\m…
How to make unforgeable money in generalised probabilistic theories
John H. Selby, Jamie Sikora
We discuss the possibility of creating money that is physically impossible to counterfeit. Of course, "physically impossible" is dependent on the theory that is a faithful descript…
Simple proof of the impossibility of bit-commitment in generalised probabilistic theories using cone programming
Jamie Sikora, John Selby
Bit-commitment is a fundamental cryptographic task, in which Alice commits a bit to Bob such that she cannot later change the value of the bit, while, simultaneously, the bit is hi…
Device-independent dimension test in a multiparty Bell experiment
Zhaohui Wei, Jamie Sikora
A device-independent dimension test for a Bell experiment aims to estimate the underlying Hilbert space dimension that is required to produce given measurement statistical data wit…
Fidelity of quantum strategies with applications to cryptography
Gus Gutoski, Ansis Rosmanis, Jamie Sikora
We introduce a definition of the fidelity function for multi-round quantum strategies, which we call the strategy fidelity, that is a generalization of the fidelity function for qu…
Device-independent dimension tests in the prepare-and-measure scenario
Jamie Sikora, Antonios Varvitsiotis, Zhaohui Wei
Analyzing the dimension of an unknown quantum system in a device-independent manner, i.e., using only the measurement statistics, is a fundamental task in quantum physics and quant…
Simple, near-optimal quantum protocols for die-rolling
Jamie Sikora
Die-rolling is the cryptographic task where two mistrustful, remote parties wish to generate a random -sided die-roll over a communication channel. Optimal quantum protocols for…
Completely positive semidefinite rank
Anupam Prakash, Jamie Sikora, Antonios Varvitsiotis +1
An matrix is called completely positive semidefinite (cpsd) if there exist Hermitian positive semidefinite matrices (for some …
Minimum Dimension of a Hilbert Space Needed to Generate a Quantum Correlation
Jamie Sikora, Antonios Varvitsiotis, Zhaohui Wei
Consider a two-party correlation that can be generated by performing local measurements on a bipartite quantum system. A question of fundamental importance is to understand how man…
Linear conic formulations for two-party correlations and values of nonlocal games
Jamie Sikora, Antonios Varvitsiotis
In this work we study the sets of two-party correlations generated from a Bell scenario involving two spatially separated systems with respect to various physical models. We show t…
Quantum and classical coin-flipping protocols based on bit-commitment and their point games
Ashwin Nayak, Jamie Sikora, Levent Tunçel
We focus on a family of quantum coin-flipping protocols based on bit-commitment. We discuss how the semidefinite programming formulations of cheating strategies can be reduced to o…
QMA with subset state witnesses
Alex B. Grilo, Iordanis Kerenidis, Jamie Sikora
The class QMA plays a fundamental role in quantum complexity theory and it has found surprising connections to condensed matter physics and in particular in the study of the minimu…
Ground state connectivity of local Hamiltonians
Sevag Gharibian, Jamie Sikora
The study of ground state energies of local Hamiltonians has played a fundamental role in quantum complexity theory. In this paper, we take a new direction by introducing the physi…