On 19/10/2011 21:26, Androcles wrote:
De Sautoy claims GPS satellites have to be synchronized with clocks
on the ground. That is absolute bull****, clocks in New York are five
hours behind clock in London. My mobile phone does not have an
atomic clock, yet it tells me where it is very accurately.
De Sautoy claims to be a mathematician. He presents no evidence to
support that ludicrous claim, de Sautoy the useless skinhead is one
more lying Einstein dingleberry.
BBC 2, 9:00 pm Oct 19th 2011.



For those who are interested in the science behind this: -

The clocks were artificially 'slowed' by about 39 microseconds/day
before launch so that their tick rate at their operational speed and
height would sync with the tick rate on the ground.

The adjustment required for the relative speed of the satellites is plus
7.2 microseconds per day

The adjustment required as a result of the relative gravitational field
strength at the satellites' height is minus 45.9 microseconds per day

Had the satellites not been launched, their clocks would be slow by 38
microseconds per day; but in operation their clocks remain in sync with
those on the Earth's surface.