[cowlinator (OP)]

I have a few questions about inflation.

Would the speed of light actually change, and/or would it be observed to change, according to an expanding metric?

In a small universe, we would measure 2 objects to be 1 meter apart, according to our meter-stick, and that light takes a certain time to travel between them.  After the universe expands (and thus our meter-stick expands), we would observe the objects to be 1 meter apart (even though the space between them had actually increased).  But would the length of time for light to travel between the objects change?

Also, back when the universe was small, our 2 objects would feel certain gravitational and electromagnetic forces from each other, based on their distance.  After the universe expands, and our metric also expands, the objects would be observed (using our expanded meter-stick) to have the same distance and volume, even though the distance and volume had actually increased because space expanded.  However, the mass would be the same (I believe).
The formulas for calculating gravity and electric force would predict that the strength of the forces would also remain the same.  Is this true, though?  Would the objects feel the same strength of gravitational pull even though there is more space in between them?

So, here are my root questions:
-- How does the scale of space affect the observed speed of light?
-- How does the scale of space affect forces which influenced by distance?
-- If the speed of light and the forces are observed to be the same before/after expansion, how is it possible to distinguish the scale of space, since the behavior is the same in all scales of reference?

Thanks!

[MOD EDIT - TITLE RE-FORMATTED AS A QUESTION, IN LINE WITH FORUM POLICY]

[jeffreyH]

In an expanding universe things aren't all getting larger in proportion with the expansion. If they were we would be unable to detect it! The increase in distance between galaxies must therefore reduce the attractive force between them due to gravity and also the magnitude of electromagnetic effects. Since at those distances the strength of inverse square forces are very very small, there would be little difference to observe.

[cowlinator (OP)]

Thanks for answering, Jeffrey.

So it sounds like elementary forces change in strength as the scale of space changes.  Does the speed of light also change as the scale of space changes?

[jeffreyH]

Now THAT is a very interesting question. Which I will need to think about.

NOTE: I wouldn't say the strength of the forces change. It is the background environment that changes.

[cowlinator (OP)]

In an expanding universe things aren't all getting larger in proportion with the expansion. If they were we would be unable to detect it!

I wouldn't say the strength of the forces change. It is the background environment that changes.

If the strength of the forces don't change, how do we detect inflation? 
How does one measure the background environment?