In article ,
Phillip Helbig---undress to reply writes:
At first, there is deceleration, then there is
acceleration,

What I meant was that acceleration _owing to a cosmological constant_
is constant in time. At least I believe that's the case, but I've
never had a proper course in modern cosmology. If the dark energy is
something other than (or in addition to) a cosmological constant, the
time dependence of its acceleration is likely to be different.

There is also deceleration due to normal gravitational attraction,
important only at early epochs. The net acceleration is the sum of
these.

A pure cosmological constant has w=-1 exactly and there is no
observational evidence that this is not the case, and there is
observational evidence that it is quite close to -1.

Agreed.

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