Prof will help you figure out your iPod

EVER WONDERED just how an iPod can store so many songs? Is the MP3 player's random shuffle function truly random?

All will be revealed at The Maths in your iPod, an hour-long presentation at UCD today.

Pitching his talk at Transition year, fifth- and sixth-year students, Prof Gary McGuire of UCD's School of Mathematical Sciences will explain the technique of compression, which enables each song to take up only 10 per cent of the space it normally would.

The event is part of the opening day of Maths Week, which aims to promote a positive attitude to mathematics. It is organised by the Centre for the Advancement of Learning of Maths, Science and Technology at Waterford Institute of Technology.

For his talk, Prof McGuire will also discuss encryption, the process used for credit card transactions over the internet, which also converts purchased songs into a "secret code" that can only be unlocked by an authorised device. "I want to make students aware of all the mathematics that is going on just behind the scenes in their iPods." "Mathematics has made this possible. It's what has enabled us to make iPods and put in all these features." For further details on the talk, which starts at 12.30pm at UCD, call 01-716 2120.

Meanwhile, at Trinity College Dublin at 8pm tonight, a passionate mathematician turned astronomer will speak on the search for radio emissions from extrasolar planets.

Gregg Hallinan from NUI Galway's Astronomy Centre works with powerful radio telescopes to study the nature of magnetic activity in planets and stars. "In a one sentence soundbite, here's what the talk is about: During the Northern Lights, the magnetic poles of the earth become billion-watt beacons beaming powerful radio beams into space. With the latest generation of powerful radio telescopes we can now begin to search for the same kind of radio waves from planets in orbit around other stars," he says.

Twenty-eight-year-old Hallinan says he loves to see students choosing to study maths to a high level. The talk, entitled Looking for a Pulse: Search for Radio Emission from Extrasolar Planets, is Astronomy Ireland's Colm J Cannon Memorial Lecture.

It is open to the general public, admission €7. For details contact: 01-847 0777.

Maths Week runs until next Saturday. See: www.mathsweek.ie

• Daily logic puzzle: If all knowns are truths and some unknowns are known, which of these statements must be true? (A): All knowns are unknown (B): Some truths are unknown (C): Some knowns are not unknown.

Answer tomorrow.