Galaxies and the Universe

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A New Name for the “Big Bang?” (Sky and Telescope, 1995)

The Big Boot

God’s Log-On

Fred Withair Day (“Nobody ever named anything else after me, so why not?”)

What Happens If I Push This Button?

You’re Never Going To Get It All Back In There Again

Slide 32

90% of the Universe is “Missing”

Outer Stars in Galaxies revolve faster than expected

What holds clusters of galaxies together?

Conclusion: There must be a lot of invisible mass in the Universe

Not really “missing”, just non-luminous

Slide 33

Astronomers Are Not As Upset As One Might Expect

MACHO’s (Massive Compact Halo Objects): faint stars, brown dwarfs, planets

Cool non-luminous gas

Massive Neutrinos?

WIMP’s (Weakly Interacting Massive Particles)

Magnetic monopoles

Exotic objects: strings, mini-black holes

Slide 34

Fine Tuning the Universe

Density

Much greater and the Universe would already have collapsed in on itself

Much less and stars could not have formed

Nuclear Forces

Fusion impossible

Fusion too easy

Anthropic Principle

Cosmology has to be able to explain why we exist

Slide 35

Fine Tuning the Universe

It just came out that way

It has to be that way for reasons we haven’t yet discovered

Maybe there are an infinity of universes but only those with certain parameters develop intelligent life (Multiverse)

Engineered or designed

Slide 36

Fine Tuning the Universe

Designer?

Doesn’t Explain Anything

If the Designer can create a Universe, why is c = 300,000 km/sec instead of 400,000?

If Designer had to have c = 300,000 km/sec, why? What (who?) dictated that, and why?

Who says Designer is anything pictured by any religion?

Slide 37

Misinterpreting Relativity

There are no absolutes

Speed of light is absolute

It may not be possible to be absolutely right but it is very easy to be absolutely wrong

Slide 38

Where Will It All End?

Trillions of years: Star formation ends

10-100 trillion years: Stars stop radiating

1015 – 1020 years: Planetary orbits decay

1032 – 1041 years: Protons decay?

Heat Death?

Big Crunch?

Big Bounce?

Slide 39

What Does Cosmology Imply for Philosophy?