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Announcements. Reading assignment for next time: read The Degenerate Era, The Black Hole Era, The Dark Era and The Conclusion Observing Night tonight: cloudy and cold so it is cancelled. Still need to do a training night so will try next week. I’ll check forecasts and let you know next time.
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Announcements • Reading assignment for next time: read The Degenerate Era, The Black Hole Era, The Dark Era and The Conclusion • Observing Night tonight: cloudy and cold so it is cancelled. Still need to do a training night so will try next week. I’ll check forecasts and let you know next time.
The cosmological decade is the cosmological decade Current best estimate for the age of the universe is 13.8 billion years or Thus, we are in the 10th cosmological decade
The Primordial Era -50 < h< 5
Cosmological Inflation The “bang” of the Big Bang
An Analogy for the Expanding Universe Where is the center of this universe? Is it “in” the universe?
Colored Card Questions ClassAction website Cosmology module Centerless Expansion Models Effects of Expansion Universe Changes
In-class Activity Do “The Big Bang” lecture-tutorial. Work together in groups of two or three. You have 20 minutes.
Recombination Recombination is a misnomer. The electrons and protons had never been together before this time
Where did all the matter come from? Electron-positron pair production and annihilation
Virtual particles and vacuum energy There had to have been some small number of cases where a particle was created without an antiparticle. We still don’t understand how that can be.
What is the atomic content of the Universe? The Big Bang theory predicts that the universe is made of hydrogen and helium with traces of deuterium, tritium, helium-3, lithium and beryllium
The Stelliferous Era The first generation stars may have been mostly dark matter: Dark Stars
CMB shows seeds of first galaxies The variation in temperature is only ~ one part in 105. That’s enough to give rise to structure.
First galaxies were small irregular galaxies which slowly became spirals
Which came first: the black hole at the center of the galaxy or the galaxy?
Stellar formation today takes place in giant clouds of gas & dust
Eventually only low mass stars are left The smallest red dwarf stars may live for tens of trillions of years but eventually even they die. At the end of the stelliferous era only supermassive black holes and stellar corpses are left.