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If not, why is my idea below not possible?

The general theory of relativity tells us that time is slowed down by gravitational fields. We bounced radar signals off planets further from the sun, and ones nearer to it, and found that the light bounced off nearer ones was red-shifted, due to passing through stronger gravitational fields.

The universe has a great deal of mass in it. Although far from concentrated sources of mass, space-time is 'flatter', it should still be true that everywhere within the universe is within its deep gravitational 'well'. As a consequence, all light travelling through space should be slowed in time and red-shifted proportional to how far it travels - no?

user2800708
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  • I could be wrong, but if you calculate light redshifting because, in an expanding universe, it is, in a sense, traveling out of a higher gravitational field over time (as masses in the universe grow further apart and density decreases), then you find it is different a approach but equivalent having light red shift due to the expansion of space time. I think those are just two mathematical paths to the same thing. – R. Rankin Jul 15 '16 at 19:28
  • I am asking about the general theory though, quite specifically. Does it rule out what I am suggesting somehow? – user2800708 Jul 15 '16 at 20:25
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    Time isn't slowed down in relativity. Different observers see non-local clocks running at different rates, but the rate at which a local clock runs is always the same. If we were at the bottom of a gravity well, then light from distant emitters should be blue shifted, not red shifted and things going outwards should slow down rather than accelerate. – CuriousOne Jul 15 '16 at 22:43
  • The answers given here: http://physics.stackexchange.com/questions/145209/gravitational-time-dilation-caused-by-a-galaxy-and-by?rq=1 bettter answer my question than the duplicate tired light one linked to. – user2800708 Jul 19 '16 at 14:53
  • The answers given in the lined to tired light question do not - in fact the top answer says that tired light cannot be specifically because far away super nova events are indeed time dilated - I guess I am not really asking about tired light in that case, but time dilation. – user2800708 Jul 19 '16 at 14:55

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