Method and System for Modifying Document Without Changing Hash Value

Abstract

A method for modifying a variable string (330) in a document (300) and generating a required hash value, wherein the document (300) comprises the variable string (330) and a fixed string (320). The method comprises constructing (S220) a Hamiltonian based on the variable string (330), encoding (S230) the variable string (330) into a quantum circuit (310) comprising a plurality of qubits, generating in a hash function generator (350) a hash value from the fixed string (320) and the output of the quantum circuit (310), comparing the generated hash values with a true hash value (370) in a comparator (360), determining (S280) an overlap between the generated hash value and a true hash value (370), and, on reaching a zero overlap value, determining the variable string (330), otherwise optimising (S270) parameters of the quantum circuit (310).

Dependencies are inferred from the claim text.