What We (Don't) Know About Dark Matter

The video explores the concept of dark matter, which constitutes 84% of the universe's matter. Initially a catchall term, dark matter is now a specific focus of study due to its gravitational effects on galaxies. Despite extensive evidence, its composition remains unknown. Theories range from modified gravity (MOND) to new particles like WIMPs and axions. Old physics suggests MACHOs and neutrinos, but these lack sufficient evidence. New physics explores supersymmetry and parallel universes, yet no direct evidence supports these ideas. The video concludes with a book promotion on cosmic mysteries.

What percentage of the universe's matter is believed to be dark matter?

• 100%

• 84%

• 50%

• 16%

What is MOND an acronym for?

• Massive Neutron Dynamics

• Modern Neutrino Dynamics

• Modified Newtonian Dynamics

• Magnetic Neutron Dynamics

What are MACHOs in the context of dark matter?

• Magnetic Cosmic Halo Objects

• Molecular Compact Halo Objects

• Massive Compact Halo Objects

• Massive Cosmic Halo Objects

Why are neutrinos considered unlikely candidates for dark matter?

• They interact too strongly with matter

• They produce too much light

• They are too fast to clump together

• They are too slow to clump together

What does WIMP stand for?

• Widely Interacting Massive Particles

• Weakly Interacting Massive Particles

• Weakly Interacting Molecular Particles

• Widely Interacting Molecular Particles

What are axions originally predicted to solve?

• A problem in cosmology

• A problem in classical mechanics

• A problem in particle physics

• A problem in quantum mechanics

What is the concept of supersymmetry in relation to dark matter?

• Every particle has a cosmic twin

• Every particle has a magnetic twin

• Every particle has a heavy twin

• Every particle has a light twin