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Cosmology

Dark Energy

Definition

A hypothetical form of energy that permeates all of space and drives the accelerating expansion of the universe. It constitutes approximately 68% of the total energy content of the universe. Its nature remains one of the biggest mysteries in modern physics.

Related Terms

Dark Matter

A hypothetical form of matter that does not emit, absorb, or reflect light. Its existence is inferred from gravitational...

Big Bang

The prevailing cosmological model explaining the origin of the universe from an initial state of extremely high density ...

Cosmic Microwave Background

Electromagnetic radiation left over from the early universe, about 380,000 years after the Big Bang. It is the oldest li...

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