Why Is the Universe Expanding

question 135

Multiple Choice

Why is the universe expanding?

• A) The energy from all the stars is heating the universe, making it expand like a gas that is heated.
• B) Spacetime itself is expanding, carrying the galaxies (or superclusters of galaxies) with it.
• C) The universe is not expanding-it is we who are getting smaller, making the universe seem bigger and bigger.
• D) An infinitely dense clump of matter exploded, sending the galaxies (or superclusters of galaxies) hurtling out through space.

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Definitions:

Dimethylheptanoic Acid

denotes a hypothetical organic compound, potentially misnamed, suggesting a heptanoic acid derivative substituted with two methyl groups.

γ-hydroxypentanoic Acid

An organic compound characterized by a five-carbon chain with a hydroxyl group attached to the third carbon and a carboxylic acid group at the end.

γ-hydroxy-γ-methylbutyric Acid

An organic compound, structurally related to β-hydroxy-β-methylbutyrate (HMB), and is involved in the biosynthesis and metabolism of fatty acids.

δ-hydroxyvaleric Acid

An organic compound that is structurally a hydroxylated form of valeric (pentanoic) acid, where the hydroxyl group is on the δ-carbon.