# [time-nuts] UTC and leap seconds

Mike S mikes at flatsurface.com
Sat Jun 12 00:41:25 UTC 2010

```At 10:46 AM 6/11/2010, iovane at inwind.it wrote...
>(Speculative hint: We accept that the universe is expanding. Might
>this affect
>the fine structure of matter, including cesium atoms? Is there any
>proof? What is easier to think? a) the expansion of the universe
>doesn't affect
>at all the properties of matter. b) it might.).

If the expansion affected everything, how would we know? Are you
claiming that it affects different things differently? Why? (if it
affects all things equally, then both the earth and clocks would
slow/speed the same, and we wouldn't observe the earth slowing down)

The universe, as a whole, is expanding. The matter and objects within
it are not (generally - some things like my beer belly are, but that's
unrelated to universal expansion). The result is objects, on an
universal scale, stay the same size but get farther apart. To your
point (expansion affecting small structure), why would expansion take
effect at very large scales, and very small scales, but not at the
scales in between?

But, relativity (not just Einstein's form) can apply everywhere. One
can create complex math/physics which allows the Earth to be at the
center of the universe, with everything else revolving (in very complex
orbits) around it. Having done so, no one can "prove" that it's not
true. But, that's not what most people accept as "fact," because it is
FAR from the simplest explanation of what we observe. So, if you want
to believe that clocks speed up, and the earth's rotation remains
constant, you can. But don't expect others to accept that.

```