Contrast between contraction and expansion of universal existence.

The energy from the Big Bang drove the early expansion of the universe. Since then, gravity and dark energy have been involved in a cosmic tug of war. Gravity pulls galaxies closer together; dark forces push them away. A singularity is a point where some property is infinite. For example, at the center of a black hole, according to classical theory, the density is infinite, because a finite mass is compressed into a zero volume. So it is a singularity.

Universal contraction.
1. A black hole is a region of three-dimensional space where a gravitational field is so intense that no matter or radiation can escape. Gravity is so strong there because matter is squeezed into a tiny space. This is one of the similar phenomena of universal contraction.

Universal expansion.
2. The Big Bang is the rapid expansion of matter or energy from conditions of extremely high density and temperature in a point like state that marks the origin of the universe according to current cosmological theory. In the early stages of the Big Bang, the universe underwent a period of extremely rapid expansion in its first few moments, known as exponential expansion or inflation. However, dark energy is a hypothetical form of energy that exerts a negative, repulsive pressure, behaving like the opposite of gravity. This has been hypothesized to account for some observational properties, which show that the universe is undergoing an accelerated expansion. These are universal expansions.

#universalcontraction #universalexpansion

Tug of war between gravity and antigravity:

Gravity pulls galaxies closer together; dark energy pushes them apart. 

Whether the universe is expanding or contracting depends on which force dominates, gravity or dark energy.

Scientifically it is understood that inside galaxies baryonic and dark matters overcome dark energy so gravity wins and keeps galaxies together but when it comes to intergalactic space, it is said that dark energy overcomes baryonic and dark matters and wins the fight, so galaxies are moving away.

Besides there is zero gravity spheres around each gravitationally bound objects, either in galactic form or any forms of clusters of galaxies. 

It is understood that the gravitating mass of dark energy is <0. 

#DarkEnergy #antigravity #baryonicmatter #darkmatter #gravity