Unconditionally Secure Bit Commitment with Flying Qudits

TL;DR

This paper introduces a novel, perfectly secure quantum bit commitment protocol using flying qudits, leveraging quantum physics principles like no-cloning and relativity to achieve unconditional security.

Contribution

It presents a new physics-based quantum cryptography method for unconditionally secure bit commitment using flying qudits and relativistic constraints.

Findings

Protocol achieves perfect security based on quantum and relativistic principles

Utilizes quantum teleportation and light-speed quantum state transmission

Provides a new approach to secure cryptographic commitments

Abstract

In the task cryptographers call bit commitment, one party encrypts a prediction in a way that cannot be decrypted until they supply a key, but has only one valid key. Bit commitment has many applications, and has been much studied, but completely and provably secure schemes have remained elusive. Here we report a new development in physics-based cryptography which gives a completely new way of implementing bit commitment that is perfectly secure. The technique involves sending a quantum state (for instance one or more photons) at light speed in one of two or more directions, either along a secure channel or by quantum teleportation. Its security proof relies on the no-cloning theorem of quantum theory and the no superluminal signalling principle of special relativity.