Former privacy and civil rights lawyer at the Electronic Frontier Foundation, Nate Cardozo explained that the ability to safely and openly communicate is crucial to a free society, and benefits everyone whether one has anything to hide or not.
For Debbie Leung, professor in the Department of Combinatorics and Optimization in the Faculty of Mathematics, it’s one of the driving forces behind her work in the theory of quantum communication. “Everyone should be given the option to speak privately, to communicate securely,” she said.
Communication—the sending and receiving of information—happens constantly. When we make phone calls, browse the Internet, or buy groceries on credit cards, we send some type of data through a communication channel.
The same fundamental process applies to quantum communication, except thanks to the advantages offered by the quantum channel and quantum data, it is a more secure method of sharing information.
How does it work?
A quantum communication channel can be engineered to guarantee privacy by allowing the communicating parties to detect the presence of an eavesdropper, like a hacker. Quantum data cannot be copied, and cannot even be learnt without being corrupted. By this definition, when you send or receive quantum information reliably, you know that no one has learned about the information, since the eavesdropper introduces noise in the data every time they try to steal a peek at the data. When the communicating parties are alerted to the eavesdropping activity, they abort the mission.
This is also what makes quantum communication difficult. That single copy of the information has to make its way from the sender to the receiver; currently, the fragility of quantum states limits this distance.
Working to advance quantum communication
Leung, with other IQC researchers and collaborators around the world, is working to advance quantum communication, improving its practicality by proposing theoretical methods to make quantum communication more robust, thereby extending the distance that quantum data can travel and contributing to a world where we can communicate securely.
Protecting our private communication isn’t just about keeping our banking information safe. It’s preserving our right to share information, learn about the world around us, and make informed decisions for the benefit of society.