Question

In: Physics

Which of the following is FALSE about dark matter? A. It can explain the velocities of...

Which of the following is FALSE about dark matter?

A. It can explain the velocities of stars in their orbits around galaxies.

B. It gives rise to gravitational lensing.

C. It does not interact with any known force.

D. It is not described in the particle physics Standard Model.

Solutions

Expert Solution

A. is definitely true because dark matter was proposed to explain the anomalous velocities is stars in galaxies. B. is also true as light bends in the gravitational field of intergalactic dark matter, on its path toward Earth's telescopes. D. is also true as the particle physics standard model had no obvious explanation for the origin of dark matter although recently, some candidate particles for dark matter have been predicted. C. is false because dark matter does interact gravitationally. It just doesn't interact electromagnetically and that's why we can't see it through our conventional telescopes.

Therefore, C. is false.


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