The Big Bang & The Origin of Atoms

Initial Observations

• In the 1920’s, Edwin Hubble who was making telescopic observations of galaxies outside the Milkyway galaxy and noticed that each galaxy appeared to be moving away from each other

The Doppler Effect for Sound: Noisy Moving

Trains• Imagine a stationary listener

hearing a passing train• As the train moves toward the

listener, the pitch increases• As the train moves away, the pitch

decreases

Pitch: Changes in the Wavelength of Sound

• As sound wave are being created as they are moving toward a listener they effectively shorten creating a higher pitch

• As they move away the length creating a lower pitch

The Red Shift: Doppler Effect for Light

• Hubble was observing light not sound

• The light from the galaxies he observed was more red than expected

The Visible Light Spectrum

• ROYGBIV• Light at the red

end of the spectrum has long wavelengths and low energy

• Light at the violet end of the spectrum has short wavelengths and high energy

Hubble’s Conclusions

• Galaxies are moving away from each other (like spots on a balloon)

• At some time in the past, all the matter in the universe may have been closer together

• In the beginning, the universe started expanding (The Big Bang) and is still doing so

The Early Universe

• If universe was smaller in space, then it was very hot

• Matter could not have existed as it does today

From then to Now

• 6 Quarks, 6 Leptons, and 1 Grand Unified Force holding things together

• Quarks come together to form protons and neutrons. The electron is the most common Lepton.

• Protons a nd neutrons come together to form nuclei with free electrons (a Plasma)

• The first atoms form• Atoms bond forming

simple gas compounds of hydrogen, helium, and lithium

• Stars form and create other elements through fusion

• Some of these elements form solid masses called planets

Big Bang Animation & Information

• http://expositions.bnf.fr/ciel/elf/1big/big.htm

• http://www.particleadventure.org/