Âé¶¹´«Ã½

Physics

Quantum trick lets one particle send messages two ways at once

By Anil Ananthaswamy

26 February 2018

Green laser beam in darkness passing through optical equipment

Quantum communications could also send secret messages

Roger Ressmeyer/Corbis/VCG/Getty

In the quantum world, particles behave as if they are in two places at once. It turns out this bizarre property allows two people to send each other one bit of information using a single particle – something that is impossible with classical communications.

Say Alice and Bob each want to send the other a piece of information in the form of a 0 or a 1. In classical communications, each has to send the other a particle encoded with that information. So, you need two particles.

Now, at…

Sign up to our weekly newsletter

Receive a weekly dose of discovery in your inbox. We'll also keep you up to date with Âé¶¹´«Ã½ events and special offers.

Sign up

To continue reading, today with our introductory offers

or

Existing subscribers

Sign in to your account
Piano Exit Overlay Banner Mobile Piano Exit Overlay Banner Desktop