Lecture
What is the universe made of?
- Current composition is estimated at 5% normal matter, 27% dark matter, and 68% dark energy, with dark matter integral to the formation of large-scale structures.
- Gravity is projected to act as the primary organizer of matter into galaxies, clusters, stars, and solar systems for the first 10 billion years.
- Observational efforts aim to increase precision in locating dark matter, while experiments at the Large Hadron Collider in Switzerland carry some probability of detecting dark matter particles.
- Dark energy is expected to increase as space expands, providing a growing force that pushes the universe apart.
- The future trajectory depends on whether the expansion rate accelerates, remains constant, or changes, with the exact behavior remaining an unknown variable.
- If acceleration increases, dark energy may eventually trigger a "Big Rip," ripping apart clusters, galaxies, solar systems, and planets.
- If dark energy's dominance leads to the universe thinning out, the Big Rip scenario could result in existence fading away.
- An increase in dark matter's influence could cause the universe to collapse back upon itself in a "Big Crunch" event.
- If neither force undergoes dramatic change, the universe may continue to expand outward indefinitely.
- Changes in the rate of acceleration expansion carry profound implications for the future of the universe, though the likelihood of such changes is not quantified.