EPSRC Reference: 
EP/Y004477/1 
Title: 
Variational Quantum Algorithms for Structured Lattices 
Principal Investigator: 
Ling, Dr C 
Other Investigators: 

Researcher CoInvestigators: 

Project Partners: 

Department: 
Electrical and Electronic Engineering 
Organisation: 
Imperial College London 
Scheme: 
Standard Research 
Starts: 
01 June 2023 
Ends: 
31 March 2025 
Value (£): 
562,376

EPSRC Research Topic Classifications: 

EPSRC Industrial Sector Classifications: 

Related Grants: 

Panel History: 
Panel Date  Panel Name  Outcome 
25 Apr 2023

Software Enabled Quantum Computation

Announced


Summary on Grant Application Form 
The pursuit of classical encryption protocols that are resistant to quantum attacks is known as postquantum cryptography (PQC). The majority of these protocols are based on latticebased cryptography, which encrypts data using highdimensional lattices. Latticebased cryptography builds cryptographic primitives by utilising lattice theory and the hardness of latticerelated problems. Unlike current publickey schemes based on factoring or discrete logarithm, latticebased cryptography appears to be resistant to quantum attacks. The shortest vector problem (SVP), which seeks the shortest nonzero vector of a given lattice, is at the heart of these protocols. Lattices with some structure, i.e. structured lattices, are typically used to improve the efficiency of these protocols. In fact, three out of the four PQC schemes recently standardized by NIST, are based on structured lattices. However, the quantum hardness of structured lattices is poorly understood.
We have already made inroads into the direction of quantum algorithms for plain lattices. The ambition of this project is to advance the research in this direction to a higher level, namely, to tackle the problems of structured lattices, which underpin NIST's PQC protocols. In this project, we aim to develop variational quantum algorithms that take advantage of the structure of these lattices to solve their SVP, thereby permitting a proper quantum cryptanalysis of PQC protocols. The goal of cryptanalysis is not to jeopardize information security, but to reveal potential weaknesses of encryption protocols so that stronger security can be assured.

Key Findings 
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Impacts 
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Summary 

Date Materialised 


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Project URL: 

Further Information: 

Organisation Website: 
http://www.imperial.ac.uk 