Big Questions in Science

2

: moving clocks run slower

Big Questions in Science, fall 2012. SdH, AUC

Big Questions in Science, fall 2012. SdH, AUC 3

4

Big Bang theory: • What it says • Predictions and tests • The first three minutes • Brief history of the universe

Big Questions in Science, fall 2012. SdH, AUC

Big Questions in Science, fall 2012. SdH, AUC 5 The Earth, as seen from the Moon, looks like a regular planet. Not special at all!

Big Questions in Science, fall 2012. SdH, AUC 6

http://www.bloomberg.com/news/2011-07-21/shuttle-landing-marks-nasa-shift-to-commercial-space-efforts.html

Big Questions in Science, fall 2012. SdH, AUC 8

Manned missions to Moon, Mars Unmanned:

Curiosity on Mars (August 2012)

Juno will arrive Jupiter 2016

Beyond Pluto

Telescopes and Observatories

Hubble Telescope (Endeavour)

International Space Station

Big Questions in Science, fall 2012. SdH, AUC 9

Big Questions in Science, fall 2012. SdH, AUC 10

Big Questions in Science, fall 2012. SdH, AUC 11

The universe began at a specific time in the past, and it has been expanding ever since.

Space itself expands:

Raisin-bread analogy

Expanding balloon

Big Questions in Science, fall 2012. SdH, AUC 12

Universal expansion: Hubble’s Law Cosmic Microwave Background (CMB) Abundance of light elements

Big Questions in Science, fall 2012. SdH, AUC 13

Mount Wilson telescope Hubble found distant galaxies, measured distance. Redshift: colors were shifted towards red.

Big Questions in Science, fall 2012. SdH, AUC 14

Big Questions in Science, fall 2012. SdH, AUC 15

Hubble Space Telescope

Big Questions in Science, fall 2012. SdH, AUC 16

http://www.lon-capa.org/~mmp/applist/doppler/d.htm

Waves “pile up” in the direction of the motion.

Frequencies appear higher (shorter wavelengths).

Same effect for stars and galaxies.

Big Questions in Science, fall 2012. SdH, AUC 17

Big Questions in Science, fall 2012. SdH, AUC 18

Method can be used to detect exoplanets

Big Questions in Science, fall 2012. SdH, AUC 19

Edwin Hubble 1929

Big Questions in Science, fall 2012. SdH, AUC 20

Universal expansion: Hubble’s Law Cosmic Microwave Background (CMB) Abundance of light elements

Big Questions in Science, fall 2012. SdH, AUC 21

Big Questions in Science, fall 2012. SdH, AUC 22

Big Questions in Science, fall 2012. SdH, AUC 23

Penzias and Wilson, 1965

Big Questions in Science, fall 2012. SdH, AUC 24

Universal expansion: Hubble’s Law Cosmic Microwave Background (CMB) Abundance of light elements

Big Questions in Science, fall 2012. SdH, AUC 25

Big Questions in Science, fall 2012. SdH, AUC 26

Stars consist mostly of hydrogen

Big Questions in Science, fall 2012. SdH, AUC 27

http://www.chem.ufl.edu/~itl/2045/lectures/lec_1.html

Big Questions in Science, fall 2012. SdH, AUC 28

http://en.wikipedia.org/wiki/File:Cosmological_Composition_%E2%80%93_Pie_Chart.svg

Big Questions in Science, fall 2012. SdH, AUC 29

Big Questions in Science, fall 2012. SdH, AUC 30 http://ut-images.s3.amazonaws.com/wp-content/uploads/2009/10/crabnebulawallpaper.jpg

Universal expansion: Hubble’s Law Cosmic Microwave Background (CMB) Abundance of light elements

Big Questions in Science, fall 2012. SdH, AUC 31

Big Questions in Science, fall 2012. SdH, AUC 32

Key concepts at each scale: • Time and space • Density • Temperature • Complexity • Radiation vs. matter • Forces

Big Questions in Science, fall 2012. SdH, AUC 33

A Brief Cosmic History

Gravity Electromagnetic Weak nuclear Strong nuclear

Big Questions in Science, fall 2012. SdH, AUC 34

Big Questions in Science, fall 2012. SdH, AUC 35

http://www.nationmaster.com/encyclopedia/Graphical-timeline-from-Big-Bang-to-Heat-Death http://russherman.com/Talks/FirstThreeMinutes_CollegeDay.pdf

Hot soup

Universe grows factor of

between and

s from

cm to 10 m

Explains smoothness.

Matter Era Ratiation Era

Quarks too energetic to bind W, Z indistinguishable from photons

Mix protons, neutrons, electrons and their anti-particles. Production and annihilation in balance. Number proton anti-proton pairs same as photons, same baryons and anti-baryons, small excess 1 in

.

Temperature below rest energy of the proton; proton anti-proton pairs annihilate. Only small primordial excess of protons remains.

Radiation and leptons. Muon-antimuon pairs annihilate, protons and neutrons transmute via weak interactions.

Plasma: Electron excess equals proton excess (charge neutrality). Photons scatter off electrons, matter and radiation are a single fluid, radiation provides pressure. 4000 K hydrogen forms, deuterium and helium. Helium abundance of 25 % as observed.

The First Three Minutes

Big Questions in Science, fall 2012. SdH, AUC 36

http://chronicle.uchicago.edu/060713/darkmatter.shtml

Big Questions in Science, fall 2012. SdH, AUC 37

Big Questions in Science, fall 2012. SdH, AUC 38

Big Questions in Science, fall 2012. SdH, AUC 39

http://journalofcosmology.com/Multiverse9.html http://mossdreams.blogspot.com/2011/01/endless-doppelgangers-in-multiverse.html

Physics and religion two separate modes of enquiry. Physics aims at mathematical explanation of the

mechanisms. Realm of observation.

Religion looks for meaning and causes on a different level.

Generically no logical contradictions possible. There may be overlaps.

Rabbi Dr. Tzvi Marx: “Every traditionally raised Jewish child knows (…) that the Bible is not a a a a scientific book.” Big Questions in Science, fall 2012. SdH, AUC 40