Re: 18th gear and getting nowhere...


Rob Morley wrote:
On Thu, 17 Jul 2008 18:20:38 +0100
"Lloydd" <tom@xxxxxxxxxxx> wrote:

Odd things that occur in my head when I am cycling...

If the earth is rolling slowly under my tyres at the same speed I am travelling in the opposite direction it is spinning, in terms of
space... I am getting nowhere...

The Earth isn't just spinning on its axis, it's also orbiting the
Sun, which is moving within our galaxy ... so where is the fixed point?
I suppose logically you could take it to be the centre of the
universe, the bit of space that everything is expanding away from after
the Big Bang, but as far as I'm concerned it might as well be me -
everything that I perceive is relative to where I experience it from,
so I am the centre of my own universe.

From what I remember, there is no such thing as the centre of the universe. However there is such thing as an absolute frame of reference for rotation.

If you really are interested in this, there are a few good books on special and general relativity,
Essentials of modern physics by T R Sandin provides some simple stuff on special relativity, It might be in a local library.
The New World of Mr. Tompkins: George Gamow's Classic Mr. Tompkins in Paperback
is well worth a read in your want to read silly storys about modern physics. Should be in a few large libraries, and definately in any physics University library.
.

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