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Natural Science 120. Prof. Andrew Reynolds CC219. Where are we in the universe?. Aristotle (384-322 BCE). Copernicus (1473-1543). Kepler (1571-1630) Galileo (1564-1642). Newton (1642-1727). Einstein (1879-1955). Edwin Hubble.
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Natural Science 120 Prof. Andrew Reynolds CC219
Edwin Hubble • Red-shifting of galaxies implies they are moving away and universe expanding • Implies in past universe was much, much smaller (sub-atomically small) • ‘The Big Bang’
The Big Bang • Creation of Space and Time • What caused it? • A Supernatural Intelligence? (God) • A random fluctuation in the quantum vacuum? • Question a non-starter: causes presuppose existence of space-time; ‘creation’ of space-time could have no cause in the standard sense
Fine-Tuning Argument • Physical constants (mass of electron, strength of nuclear forces etc.) seem to be ‘perfectly’ tuned so to permit the formation of life in the universe. Why? • Coincidence or not? • Chance or sign of intelligence/purpose?
Anthropic Principle • Two Forms: • Q1: “Why do we find the constants set such that we are possible?” • D’uh! If they weren’t set such as to allow for intelligent life we wouldn’t be here to ask the question. (Like a million dollar lottery ticket holder asking ‘why am I, a millionaire, in possession of this winning ticket?’) • Q2: “Why are the constants, of all the possible values they could have taken, set at those values which permit (intelligent) life?” (Like anyone asking “Why did I win the lottery?”) • Maybe because God set them that way; • or maybe it’s just luck/chance; (“But isn’t that just too improbable?”) • Maybe there are many universes in which the constants do take different values, and of course we occupy one of those universes that are suitable for life (Multiple Universes hypothesis)
The conditions on earth and in the solar system are just so perfectly arranged that it can’t possibly be an accident that there is life here; there must have been some intelligence behind it. Is it so surprising we find life in the place that is most suited to it? But why is there life at all? Design? Or inevitable result of the laws of chemistry and physics?
Finding Our Place in the Universe Where are we? Old Answer: At the center of the universe New Answer: We don’t know where we are in any absolute sense; only in a relative sense – relative to other bodies (planets, stars, galaxies) and ‘here’ is no place special
Only makes sense to ask where we are in an absolute sense (where are we really) if the universe has boundaries – and that we do not know • We do know much better how to describe motion accurately • And we can use this theoretical knowledge to do things – i.e. technology has vastly improved (space travel to other planets, satellites, GPS)
Second term In what relation do humans stand (according to modern science) in relation to other forms of life? Are we superior? Are we the ‘most highly evolved’?
