What Is the Difference Between Dark Matter and Dark Energy

question 71

Multiple Choice

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.

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Definitions:

Instrumental Learning

Instrumental Learning, also known as Operant Conditioning, is a learning process wherein behavior is modified through reinforcement or punishment.

Conditioned Stimulus

In classical conditioning, a previously neutral stimulus that, after becoming associated with the unconditioned stimulus, eventually comes to trigger a conditioned response.

Conditioned Response

The learned reaction to a previously neutral stimulus, brought about by conditioning.

Reflex

An automatic, involuntary response to a stimulus that does not involve conscious thought, designed to protect the body.