LECTURE 26, DECEMBER 7, 2010 ASTR 101, SECTION 3 INSTRUCTOR, JACK BRANDT 1ASTR 101-3, FALL 2010

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Question 9 In the first few minutes after the Big Bang a) the universe cooled and formed neutral matter. b) the cosmic microwave background radiation was released. c) electrons recombined with protons. d) hydrogen fused into deuterium and then helium. e) the universe was governed by one unified super-force.

a) the universe cooled and formed neutral matter. b) the cosmic microwave background radiation was released. c) electrons recombined with protons. d) hydrogen fused into deuterium and then helium. e) the universe was governed by one unified super-force. Question 9 In the first few minutes after the Big Bang The production of elements heavier than hydrogen by nuclear fusion is “primordial nucleosynthesis.” The amount of deuterium we see today is an important clue to the density of this early universe.

ASTR 101-3, FALL 20105

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a) the Steady State Theory. b) the Grand Unified Theories. c) the Inflationary epoch. d) dark matter. e) decoupling of matter from radiation. Question 10 The universe appears flat; this is explained by

a) the Steady State Theory. b) the Grand Unified Theories. c) the Inflationary epoch. d) dark matter. e) decoupling of matter from radiation. Question 10 The universe appears flat; this is explained by

ASTR 101-3, FALL

ASTR 101-3, FALL

ASTR 101-3, FALL

ASTR 101-3, FALL

ASTR 101-3, FALL

ASTR 101-3, FALL 2010 COSMOLOGY SUMMARY Time since the Big Bang = 13.7 billion yrs. First stars at 400 million years The Universe is flat or Ω o = 1 CONTENTS: Ordinary Matter = 4%; Dark Matter = 22%; Dark Energy = 74% 17