English
Related papers

Related papers: Quantum weak coin flipping with arbitrarily small …

200 papers

This note presents a quantum protocol that demonstrates that_weak_ coin flipping with bias approximately 0.239, less than 1/4, is possible. A bias of 1/4 was the smallest known, and followed from the strong coin flipping protocol of…

Quantum Physics · Physics 2007-05-23 Iordanis Kerenidis , Ashwin Nayak

We present a family of loss-tolerant quantum strong coin flipping protocols; each protocol differing in the number of qubits employed. For a single qubit we obtain a bias of 0.4, reproducing the result of Berl\'{i}n et al. [Phys. Rev. A 80,…

Quantum Physics · Physics 2010-12-24 N. Aharon , S. Massar , J. Silman

Weak coin flipping is a cryptographic primitive in which two mutually distrustful parties generate a shared random bit to agree on a winner via remote communication. While a stand-alone secure weak coin flipping protocol can be constructed…

Quantum Physics · Physics 2025-06-25 Jiawei Wu , Yanglin Hu , Akshay Bansal , Marco Tomamichel

As in modern communication networks, the security of quantum networks will rely on complex cryptographic tasks that are based on a handful of fundamental primitives. Weak coin flipping (WCF) is a significant such primitive which allows two…

In this article we show for the first time that quantum coin flipping with security guarantees that are strictly better than any classical protocol is possible to implement with current technology. Our protocol takes into account all…

Quantum Physics · Physics 2011-11-11 Anna Pappa , André Chailloux , Eleni Diamanti , Iordanis Kerenidis

In this paper, we present a loss-tolerant quantum strong coin flipping protocol with bias 0.359. This is an improvement over Berlin etal's protocol [BBBG08] which achieves a bias of 0.4. To achieve this, we extend Berlin et al.'s protocol…

Quantum Physics · Physics 2011-03-15 André Chailloux

Bit commitment is a fundamental cryptographic primitive with numerous applications. Quantum information allows for bit commitment schemes in the information theoretic setting where no dishonest party can perfectly cheat. The previously…

Quantum Physics · Physics 2011-02-09 André Chailloux , Iordanis Kerenidis

We present a quantum protocol for the task of weak coin flipping. We find that, for one choice of parameters in the protocol, the maximum probability of a dishonest party winning the coin flip if the other party is honest is 1/sqrt(2). We…

Quantum Physics · Physics 2009-11-07 R. W. Spekkens , Terry Rudolph

We investigate coin-flipping protocols for multiple parties in a quantum broadcast setting: (1) We propose and motivate a definition for quantum broadcast. Our model of quantum broadcast channel is new. (2) We discovered that quantum…

Quantum Physics · Physics 2016-11-17 Andris Ambainis , Harry Buhrman , Yevgeniy Dodis , Hein Roehrig

It is believed that superselection rules in quantum mechanics can restrict the possible operation on a qbit. If this was true, the model used by Mayers for the impossibility of bit commitment and by Kitaev for the impossibility of coin…

Quantum Physics · Physics 2007-05-23 Dominic Mayers

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 coin-flipping is impossible in both classical and quantum…

Quantum Physics · Physics 2020-10-28 Jamie Sikora , John H. Selby

We introduce a multi-coin discrete quantum random walk where the amplitude for a coin flip depends upon previous tosses. Although the corresponding classical random walk is unbiased, a bias can be introduced into the quantum walk by varying…

Quantum Physics · Physics 2009-11-10 Adrian P. Flitney , Derek Abbott , Neil F. Johnson

Weak coin flipping is an important cryptographic primitive$\unicode{x2013}$it is the strongest known secure two-party computation primitive that classically becomes secure only under certain assumptions (e.g. computational hardness), while…

Quantum Physics · Physics 2025-12-03 Atul Singh Arora , Jérémie Roland , Chrysoula Vlachou , Stephan Weis

Performing complex cryptographic tasks will be an essential element in future quantum communication networks. These tasks are based on a handful of fundamental primitives, such as coin flipping, where two distrustful parties wish to agree…

While it is well known that a Turing machine equipped with the ability to flip a fair coin cannot compute more that a standard Turing machine, we show that this is not true for a biased coin. Indeed, any oracle set $X$ may be coded as a…

Other Computer Science · Computer Science 2007-05-23 Toby Ord , Tien D. Kieu

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 optimizing a linear combination of fidelity functions over a…

Quantum Physics · Physics 2018-03-22 Ashwin Nayak , Jamie Sikora , Levent Tunçel

Weak coin flipping (WCF) is a fundamental cryptographic primitive for two-party secure computation, where two distrustful parties need to remotely establish a shared random bit whilst having opposite preferred outcomes. It is the strongest…

Quantum Physics · Physics 2023-01-03 Atul Singh Arora , Jérémie Roland , Chrysoula Vlachou

In this paper, we prove classical coin-flipping secure in the presence of quantum adversaries. The proof uses a recent result of Watrous [Wat09] that allows quantum rewinding for protocols of a certain form. We then discuss two…

Quantum Physics · Physics 2009-10-19 Ivan Damgaard , Carolin Lunemann

So far, most of existed single-shot quantum coin flipping(QCF) protocols failed in a noisy quantum channel. Here, we present a nested-structured framework that makes it possible to achieve partially noise-tolerant QCF, due to that there is…

Quantum Physics · Physics 2015-08-19 Sheng Zhang , Yuexin Zhang

Weak coin flipping is the cryptographic task where Alice and Bob remotely flip a coin but want opposite outcomes. This work studies this task in the device-independent regime where Alice and Bob neither trust each other, nor their quantum…

Quantum Physics · Physics 2024-04-29 Atul Singh Arora , Jamie Sikora , Thomas Van Himbeeck