@splittingzero - Still missing the point, my friend. When factoring in the effect of gravity for the total mass of the Universe, it should be slowing down, but it is accelerating. We can calculate the rate at which objects should be moving away from a single event including the mass involved and it is not behaving as it should. When we say dark energy, we're not talking about something we can define, it's just a convenient way to say something is acting on the Universe that can only be observed indirectly through effect. It could be, for example, that our understanding of gravity's properties is incomplete. It could be that this dark energy is a property of space-time that has escaped us. We don't know. Here is an article that is clear and fairly complete dealing with the issue of dark energy:

[space.com]

Yes yes, I understand, but if we know where we are on the map then we can find our way to the popcorn vendor.....

The effect is more easily explained by saying that the distance between point A and point B on an inflating globe (just a convenient way to put it) is increasing at one rate, but the more distant point C on that globe is increasing at a greater rate. The reason for this is that there is more space to expand between A and C. This is an easy thing to calculate. The problem is that the expansion is increasing at a greater rate than it should. We are able to calculate the acceleration expected from a uniform expansion and that is not what we find.

I do kind of see where you're coming from, but there is something that screws this up: galactic rotation. As far as I know, our galaxy is rotating. Also, if I recall correctly, it's also in motion as a whole, but I don't recall if it's rotating about some other point. One would have to take into account this movement when making observations of distant galaxies in regards to the shift in light wavelength, especially since these would make the most difference.

@atheist,

yes, although that description can be confusing too.