Why Is Flatness a Problem in Cosmology

question 211

Multiple Choice

Why is flatness a problem in cosmology?

• A) The total amount of known matter (even if dark matter is included) is not enough to make the universe flat.
• B) The universe appears to be flat to within observational error, yet the universe is expanding, and it is impossible for an expanding universe to be flat.
• C) The universe appears to have a hyperbolic geometry to within observational error, yet the universe is expanding, and expanding universes have to be flat.
• D) Matter is known to create bumps in the geometry of spacetime; therefore, the universe cannot be flat.

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Definitions:

Case Study

A research method involving an in-depth analysis of a single case, group, event, or community to explore and understand complex issues in context.

Case Study

An in-depth examination of an individual, group, or event to explore and understand dynamics not captured by quantitative methods.

Representative Sample

A subset of a population that accurately reflects the members of that population.

Single-Blind Study

A research experiment in which only the participants are unaware of who is receiving the treatment or placebo to prevent bias.