Notes on Theories of the Origin of the Universe (Transcript-based)

Universe

  • contains all matter, space, and time.
  • contains all the galaxies, stars, and planets.
  • Our Solar System is located in the Milky Way galaxy, which is one of many galaxies in the Universe.
  • Optical telescopes have been used for astronomical observation since the time of Galileo.

Cosmology

  • studies the origin, evolution, and fate of the universe.

Creationism

  • Genesis (one of the books of the Hebrew Bible and Christian Old Testament).
  • God created the sky, land, sea, moon, stars, and every living creature in a span of six days.

Hindu Cosmology (Rigveda)

  • Universe as an infinitely oscillating universe.
  • Cosmic egg (Brahmanda) – contains the universe; expands out of a single point called Bindu, and will eventually collapse again.

Primordial Universe (Anaxagoras)

  • Anaxagoras — Greek philosopher.
  • Cosmos was a primordial mixture of all its ingredients.
  • This mixture was set in motion by the action of the “nous” or mind.
  • Whirling motion sifted and separated the ingredients.

Atomic Universe (Leucippus and Democritus)

  • Greek philosophers.
  • Cosmos composed of tiny, inseparable, and indestructible atoms.

Big Bang Theory (Georges Henri Joseph Edouard Lemaître)

  • The universe began from a singularity, an infinitely small, hot, and dense point.
  • It rapidly expanded and continued to stretch.

Steady State Theory (Hoyle, Gold, Bondi)

  • The universe has been present ever since and therefore has no beginning and no end.
  • The density of matter in the expanding universe remains unchanged due to a continuous creation of matter.

The Big Crunch Theory (Alexander Friedman and John Wheeler)

  • At a certain point in time, the expansion will stop and the universe will collapse into itself.
  • It would pull everything inward until it becomes the biggest black hole ever.

Oscillating Universe (Richard Tolman)

  • Combines the Big Bang and the Big Crunch as part of a cyclic event.
  • Postulates that the universe goes through regular cycles of expansion and destruction.

Assignment

  • Research other theories explaining the origin of the universe.
  • Include a description of each theory.

Closing

  • Thank you for listening.