I've written of the expansion of the universe, and the contraction of the universe, go absolutely "nowhere" into "nothingness," since they perfectly cancel each other out. Between a force of gravity that draws to an infinite set, and the gravity of the constituent gravitational elements of the infinite set, that draws to those gravitational elements a universal vacuum forms and thus a vacuum energy exists one might call dark energy, the fifth force or a drawing and pushing gravity to the infinity, the Horizon, whichever, since the latter (G), develops the former, the 'dark energy', The vacuum energy, through developing he vacuum.
Regarding the universe at large, and at small as well, the physic mirrors a reverse of the Casimer Effect where externally is the separation, the expansion effect, and internally is a contraction effect of black hole (void)-like singularity. That is development of a lot of cloud mass and energy that will not only contract to higher energy galaxies and stars in the macro-verse and transform the cloud to higher energy particles in the micro-verse but energize the expansion of the universe ending in the effective mutual cancellation of contraction and expansion without terminating or diminishing either one. Of course, like an electron returning to the lower energy state of the cloud, galaxies and stars will also eventually return to the lower energy state of the cloud.
Dark energy is a force of vacuum energy, a cosmic energy of the vacuum of space itself, that acts like a repellent force of gravity, an anti-gravity, not the kind of thrusts and losses that we associate with jets and rockets.
Regarding the universe at large, and at small as well, the physic mirrors a reverse of the Casimer Effect where externally is the separation, the expansion effect, and internally is a contraction effect of black hole (void)-like singularity. That is development of a lot of cloud mass and energy that will not only contract to higher energy galaxies and stars in the macro-verse and transform the cloud to higher energy particles in the micro-verse but energize the expansion of the universe ending in the effective mutual cancellation of contraction and expansion without terminating or diminishing either one. Of course, like an electron returning to the lower energy state of the cloud, galaxies and stars will also eventually return to the lower energy state of the cloud.
Dark energy is a force of vacuum energy, a cosmic energy of the vacuum of space itself, that acts like a repellent force of gravity, an anti-gravity, not the kind of thrusts and losses that we associate with jets and rockets.