Main content
Sorry, this episode is not currently available

P vs NP (Summer Repeat)

Melvyn Bragg and guests discuss P versus NP, an unsolved problem in maths that asks if the answers to all problems can be found as easily as they can be checked.

In a programme first broadcast in 2015, Melvyn Bragg and guests discuss the problem of P versus NP, which has a bearing on online security. There is a $1,000,000 prize on offer from the Clay Mathematical Institute for the first person to come up with a complete solution. At its heart is the question "are there problems for which the answers can be checked by computers, but not found in a reasonable time?" If the answer to that is yes, then P does not equal NP. However, if all answers can be found easily as well as checked, if only we knew how, then P equals NP. The area has intrigued mathematicians and computer scientists since Alan Turing, in 1936, found that it鈥檚 impossible to decide in general whether an algorithm will run forever on some problems. Resting on P versus NP is the security of all online transactions which are currently encrypted: if it transpires that P=NP, if answers could be found as easily as checked, computers could crack passwords in moments.

With

Colva Roney-Dougal
Reader in Pure Mathematics at the University of St Andrews

Timothy Gowers
Royal Society Research Professor in Mathematics at the University of Cambridge

And

Leslie Ann Goldberg
Professor of Computer Science and Fellow of St Edmund Hall, University of Oxford

Producer: Simon Tillotson

Release date:

47 minutes

In Our Time podcasts

Download programmes from the huge In Our Time archive.

The In Our Time Listeners' Top 10

If you鈥檙e new to In Our Time, this is a good place to start.

Arts and Ideas podcast

Download the best of Radio 3's Free Thinking programme.

Podcast