Name one observation that suggests dark matter exists.

What is dark energy associated with observationally?

Why are neutrino masses an open question for particle physics?

State the enclosed-mass estimate for circular orbital speed \(v\) at radius \(r\).

Why does a flat galaxy rotation curve imply increasing enclosed mass?

What is meant by the matter-antimatter asymmetry?

Why is ordinary dim matter not enough to explain dark matter evidence?

What does \(\Omega_\Lambda\) represent in cosmology notation?

Explain why quantum gravity is an open problem.

A star orbits at \(2.0\times10^5\,\mathrm{m\,s^{-1}}\) at radius \(3.0\times10^{20}\,\mathrm m\). Estimate the enclosed mass.

Why must dark matter interact gravitationally?

Why does dark matter not have to interact strongly with light?

What would make a proposed dark-matter particle scientifically useful?

Explain why accelerated expansion cannot be concluded from redshift alone.

Why are open questions not evidence that the Standard Model is useless?

A galaxy rotation curve remains flat out to large radius. Use \(M(r)=v^2r/G\) to describe the mass profile.

Why do neutrino oscillations imply that neutrino flavour is not the same as fixed mass?

Explain why matter-antimatter asymmetry is linked to early-universe physics.

Why is dark energy described as a cosmology problem rather than a laboratory particle discovery so far?

Give two criteria for judging a proposed solution beyond the Standard Model.