It Takes Two to Entangle - a Dstl biscuit book

A simple guide to quantum physics, demystifying quantum technology using everyday language, familiar examples and analogies.


It takes two to entangle – A tea-time diversion through Quantum Physics

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This guide has been written by the Defence Science and Technology Laboratory (Dstl) as a non-technical introduction to quantum physics and the opportunities that the resulting technology can bring.

Dstl is exploring all aspects of quantum technology across all areas including: sensing, timing, communications, imaging and information processing. We have a state of the art laboratory to understand first-hand how this exciting area can benefit UK defence and security. We are also interested in developing engineering solutions for operating quantum technology outside of the laboratory, on a number of platforms, and in different types of operations and environments. If you’d like to get in touch with our team, email:

‘It Takes Two to Entangle’ is one of a series of biscuit books, designed to be dipped into and easily digested - just like a biscuit with tea.

Published 23 March 2022