How does GPS work? - Christmas Lecture with Neil Johnson

Neil Johnson shows how Global Positioning System devices use satellites and atomic clocks to work out your location.
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Watch the full first lecture of the series:
http://www.rigb.org/christmas-lectures/watch/1999/arrows-of-time/back-to-the-future?utm_source=youtube&utm_medium=social&utm_term=description

From the fabric of space-time to the limits of the quantum world, Neil Johnson takes us on a journey through time in his 1999 Christmas Lecture series "Arrows of Time".

His first lecture looks at our understanding of the role of time in the Universe and asks: if the basic laws of physics are simple, why is the Universe so complex?

Watch the full series: http://www.rigb.org/christmas-lectures/watch/1999/arrows-of-time

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