Horizon - What On Earth Is Wrong With Gravity?

29 January 2008 @ 9-9.50pm on BBC TWO

Hollywood physicist Dr Brian Cox is on a journey to answer a simple question that has baffled the world's greatest scientists for over 400 years â?? just what is gravity?

Cox takes a road trip around the USA in his quest for an answer, in the third programme of the flagship science documentary strand. He fires a laser at the moon in Texas, bends time to operate his sat nav in Denver, and tries to capture gravity itself in the swamps of Louisiana, all in a bid to find a solution to this cosmic conundrum.

On the way, he has to clamber on some seriously big shoulders. When it comes to gravity, the biggest names in the game have all had a go at cracking it: Newton managed to predict its effects and Einstein thought he'd explained how it works. However, Cox knows there's more to gravity than even these two giants worked out. Gravity may feel very familiar to us all, but this mysterious force still represents one of the biggest mysteries in science. It is a puzzle which continues to baffle the world's greatest scientists.

Combined with incredible graphics, Cox's pursuit of a true understanding of gravity ultimately leads him to the unimaginable world of quantum mechanics. Eventually, if he can find quantum gravity, his journey could lead him to an understanding of absolutely everything.