usually a laser cooling setup looks like this


LASER MODULE ========== MOLECULE ========== MIRROR

So any energy picked up by photons from laser ends up back in the laser cavity. We do this for obvious safety reasons.


I assume you objection is because you want to cool like this


LASER MODULE =========== MOLECULE ============> OUT TO SPACE


From a universe perspective it makes no difference.

In the lower example the photon goes past the molecule takes some energy from the molecule and therefore your molecule lost mass.

However your photon picked up energy and is continuing out into space with that extra energy it therefore gained mass.

From the universe perspective a molecule lost some mass a photon gained some mass the mass of the universe did not change at all.

You can take the process out as big and complex as you like so long as you can't lose heat or energy outside the universe by energy mass equivalence the universe mass remains static and constant.

You said you accepted the mass energy equivalence so therefore you are as they say "stuffed" because the only way you can now make the universe mass change is by losing or gaining energy outside the universe.

Last edited by Orac; 08/22/12 03:28 AM.

I believe in "Evil, Bad, Ungodly fantasy science and maths", so I am undoubtedly wrong to you.