PRIDE CHEKERAAt instant of the Big Bang it was the inflationary field, mediated
by the inflaton particle, which set the inflation of a scalar field.
It is the result of this inflation which was strong enough to set a
persisting expansion we observe now.
But this expansion must be decelerating with time, not
accelerating. Therefore, there seems to be an antigravity force,
whose magnitude oversize that of gravity, thus causing the
observed acceleration of the cosmos in its expansion.
It was during this moment, when it was discovered that Einstein
was not wrong, he was right, but he was not sure enough that he
was right.
The antigravity force represented by the cosmological constant
must be the one behind the observed phenomenon. This force is
negative energy welling in a vacuum of space rendering the
acceleration of the cosmos as it expands. Thus it was considered
that the cosmological constant must not be zero, but has a
certain arbitrary value depending on the rate of expansion of the
universe.
Right now we know this negative energy, the vacuum pressure,
as dark energy, which is energy of unknown origin. It is dark
energy which is pulling all galaxies away relative to us. Since
this is happening, future cosmic explorers will only have the
stars of the Milky Way to talk about, since all of the galaxies
will recessed out of view.