What is the difference between dark matter and dark energy?
A) Dark matter exists today, whereas dark energy existed only until the strong nuclear force became a separate force at the Planck time.
B) Dark energy is the energy emitted by dark matter, much as luminous energy (light) is emitted by visible matter.
C) There is no difference: Energy has mass by E = mc², and dark matter and dark energy are two names for the same effect.
D) Dark matter is attractive and slows the universal expansion, whereas dark energy is repulsive and accelerates the universal expansion.

Question

Quizplus · Accepted Answer

Dark matter and dark energy are two distinct and unrelated phenomena. Dark matter is a type of matter that does not emit, absorb, or reflect light, but its existence is inferred by its gravitational effects on visible matter. Dark energy, on the other hand, is a mysterious force that is causing the accelerated expansion of the universe. It is not caused by dark matter, and it is not related to it in any way. Dark matter is attractive and slows the universal expansion, whereas dark energy is repulsive and accelerates the universal expansion.

What Is the Difference Between Dark Matter and Dark Energy