"Thruston Hypothesis": suppose there is a kind of micro particles in our universe, called "thruston" (or "thrustino"), they run at the speed of light in vacuum in local coordinate system, in all positions, all directions, their mass is sufficiently small,, a bit like neutrino. When they encounter an object A, they are blocked partially, then the thrust acting on an object B behind the object A reduced. So there is gravity force.
For example, there is an apple over the ground, the thrust/thruston acting on the apple from the direction of the ground is partially blocked by the Earth,
while the micro particles/thruston acting on the apple from the other direction get less blocked, so the apple gets the gravity force from the Earth, it will drop to the ground.
The black hole in the universe is very special, the "thruston hypothesis" assumes that the gravitational force is due to the reduction of thrust force of the thruston. The supermassive attraction of a black hole to a nearby object is due to there is only thruston running toward the black hole.
"Thruston hypothesis" assumes that the gravitational force is due to the decrease of the thrust force of the thruston. The supermassive attraction of a black hole to a nearby object is due to there is only thruston running toward the black hole. The outer of our universe is the same as the black hole. There is no thruston outside the edge of the universe, so there is the same super gravity as the black hole to the inward near the edge of the universe, it makes our universe expand faster!
Hope this explanation can replace the dark energy hypothesis?
The radius of the observable universe is estimated to be about 46 billion light-years.
The radius is the distance from the center to the edge of the universe.
