Not the Universe we Expected

1)      Strangeness

a)      science reveals a strange world

b)      technology creates a strange world

2)      Copernican revolution

a)      the decentralization and dethroning of human experience

b)      Earth not the center of the universe - Copernicus 1543

c)       Sun not the center of the galaxy

i)        Galileo 1610 - shows that Milky Way has many stars

ii)       Immanuel Kant 1755 - proposes rotating bodies of stars

iii)     William Herschel 1785 - puts Sun at center of flat blob like galaxy

iv)     19th and 20th century - observations of spiral nebulae, discovery of stars in them

v)       Edwin Hubble 1920 - proves Andromeda "Nebula" (now called galaxy) is far, far away, cements supposition that Milky Way is a similar object.

vi)     Sun not even center of Milky Way galaxy

(1)    Sun lies approximately 27,000 light years from center

(2)    Milky Way is 100,000 light years across with  100 to 400 billion stars

vii)   Milky Way and Andromeda just two of many

(1)    100 to 500,000,000,000 galaxies

(2)    10 sextillion to 200 sextillion (10 followed by 22 zeros) stars in universe

viii)  Expanding universe

(1)    Hubble's work showed universe is expanding

(2)    This is related to idea of the Big Bang - universe began in an explosion from a single point

(3)    Will universe expand forever or will it collapse in on itself in a big crush become a key question

(4)    Answer found in cosmic background microwave radiation, remnants of the Big Bang

(a)     predicted in 1948, discovered in 1955 by Bell Labs technicians

(b)   About  2.75 Kelvin

(c)    Data from the WMAP probe (2001=2003) confirms suspicion that expansion was accelerating  

(5)    Dark energy, Dark matter - astronomers now that what we can see (including us) is only 5% of the universe - in other words we are a trivial part of universe

(6)    And our "universe" may in fact be one bubble in a much larger "multiverse"

ix)     Exoplanets (planets outside our solar system)

(1)    first one confirmed in 1992

(2)    now confirmed - 1048

(3)    estimates for Milky Way - 100 to 400 billion planets around stars, with many more rogue planets floating between stars

x)      Life remains the mystery

xi)     Mars, Europa, Enceladus  best candidates in our solar system

xii)   Astronomers search for oxygen worlds among exoplanets, would be good evidence for life

xiii)  SETI has been listening for radio signals for many years - nothing so far.

3)      Strange universe

a)      Einstein shows that time and space mutable, changing

b)      quantum mechanics , physics of subatomic particles, shows that subatomic world functions as probability waves

i)        Werner Heisenberg -  uncertainty principle 1927 - we can know momentum or position of a particle but not both. How much we know about one reduces what we know about the other.

ii)       Particles pop in and out of existence (this means black holes evaporate  - Stephen Hawking, 1974)

4)      Life Not as We Know It

a)      Evolution shows that life is changing mutable not constant

b)      Genetic engineering

i)        first demonstrated 1972

ii)       first commercially engineered plants 1986 (herbicide resistant tobacco)

iii)      first fully synthetic genome 2010 (synthetic bacteria)

c)       Age of Earth

i)        much older than we thought in previous centuries

ii)       18th-century some suggest earth was old -  75,000 to as much as 96 million years

iii)     19th century physicists use thermodynamics to suggest a cooling earth 20 to 40 million years old

iv)     Radiometric dating -  using radioactive decay of atoms to determine age pushed back age of the earth

(1)    by 1910 estimates of age of certain rocks on Earth 250 million to 1.3 billion years

(2)    by 1931 oldest rocks pushed back to between 1.6 and 3.0 billion years (accepted after 1931)

v)      dating of meteorites (believed to be remnants of planetary formation) at  4.55 billion years old, accepted as age of Earth and other planets

vi)     oldest rocks on Earth 3.8 to 4.2 8 billion years old

vii)   age of universe approximately 13.8 billion years old established by WMAP measuring of cosmic background radiation

5)      World we Made

a)      increasingly intertwined and global world

b)      Yet same technology allows for increasing individualism

c)       7 billion people, so single humans less important

d)      Yet single humans potentially capable of significant change (or disaster) with expanding technology