410 lecture on Cosmology

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The heavens declare the glory of God the skies
proclaim the work of his hands. Day after day
they pour forth speech night after night they
display knowledge. There is no speech or
language where their voice is not heard. Psalm
191-3 NIV
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When I consider your heavens, the work of your
fingers, the moon and the stars, which you have
set in place, what is man that you are mindful of
him, the son of man that you care for him? Psalm
83-4 NIV
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The Most Incomprehensible Thing About the
Universe is that it is Comprehensible Albert
Einstein
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COSMOLOGY
Three Simple Questions..........
What is the nature of the Universe? What is its
past? What is its future?
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As long as men have been looking up to the skies
at night and observing the panorama of the
heavens, some men have been wondering about the
origin and nature of the universe.
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A Portion of the Milky Way in Visible Light
What is it? Our view into the plane of our
galaxy.
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A band of light making a circle around the
celestial sphere.
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center
Milky Way Panorama
center
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Face-on View of a galaxy similar to Milky Way , a
barred spiral!
Sun is located between two major arms
We would be about here
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COSMOLOGY

• .......the study of the origin, structure, and
  evolution of the Universe

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1914 Vesto Slipher was studying rotation of the
Andromeda Nebula using the Doppler Effect
Modern Cosmology began in the early 1900s
could not observe any rotation.. did observe a
large Doppler Shift corresponding to a
blueshift equiv. to 700,000 mph
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Optical Doppler Effect similar to acoustical
doppler shifts
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• Slipher reported on work at American Astronomical
  Society meeting

• Edwin Hubble was grad student in audience and
  became interested in the project
• Hubble was a ex-lawyer turned astronomer
• By 1925 Slipher had measured 40 nebulae and found
  redshifts much more common than blueshifts
• At that time it was not known exactly what the
  fuzzy objects like Andromeda were
• local objects...in our galaxy?
• extra-galactic objects...outside our galaxy?

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General Relativity

• 1915 Albert Einstein introduced the ideas of
  General relativity
• accelerations in space-time cannot be
  distinguished from gravitation attraction
• gravitational forces are explainable as a
  curvature of space-time due to presence of mass

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Einsteins GR made 3 testable predictions

• bending of light by strong gravitational fields
• movement of perihelion point of Mercury
• gravitational redshift of spectral lines

• All 3 have been experimentally confirmed
• first 2 by early 1920s

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• Einstein used General relativity to solve for the
  structure of space-time for the universe

• his solutions were unstable and dynamic, i.e.
  they implied that the universe is changing
• Einstein believe the universe was static
• added a fudge-factor (cosmological constant) to
  his equations to make the answer static

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1922 Russian mathematician Alexander Friedmann
disc. error in Einsteins calcs. (he had divided
by zero at one point)

• Friedmann showed there were 3 stable solns and
  all were dynamic
• each different soln was characterized by a unique
  curvature of space
• spherically curved
• hyperbolically curved
• flat

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• 1917 Edwin Hubble began work at Palomar
  observatory and with help of Milton Humason
  (acknowledged as the best observational
  astronomer in the world - and totally
  self-taught!) expanded Sliphers measurements and
  began to try to interpret their meaning

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Humasson
Hubble
Einstein
1931
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The nature of Sliphers fuzzy objects or
nebulae was being vigorously debated by
astronomers were they galactic or
extra-galactic?

• 1920 Curtis-Shapley debate at the National
  Academy of Sciences over the nature of
  Nebulae...(inconclusive! No good data to
  differentiate models)

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The Andromeda Galaxy (M31)

• Using Palomar telescope, Hubble Humason were
  able to resolve individual Cepheid Variables in
  Andromeda Nebula

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Cepheid Variables in the Andromeda
Galaxy......... identified by red arrows
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Cepheid Variables are very large and bright stars
with variable light output (due to pulsations in
size). They are identifiable by their
characteristic light curve.
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Henrietta Leavitt, a female assistant at Harvard
Observatory, had discovered a linear relationship
between period luminosity for Cepheid Variable
stars.

• At first even Hubble could not accept what an
  application of Henrietta Leavitts period
  luminosity relation for Cepheids implied....
• a distance MUCH larger than any distance
  estimated for other nebulous objects

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Leavitts Period-Luminosity Relation for Cepheid
Variable Stars
The star with period of 30 days has a luminosity
of 10,000 suns
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Knowing the period gives one a measure of the
stars luminosity (actual total energy output of
the star) and comparing this with its perceived
brightness (from Earth), one can use the inverse
square law and estimate the distance to the
object.
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Hubble soon discovered several Cepheid variables
all implying the same result...
Using the Period-Luminosity relation for
Cepheids, they determined that the nebula was at
least 2.2 million light years away and therefore
EXTRAGALACTIC!
This showed that many of the fuzzy nebulae were
actually galaxies like our own
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• Hubble-Humason examined several dozen galaxies
  within 7 Million light years in which Cepheids
  could be resolved, and made another astonishing
  discovery!

• All of the distant galaxies in all directions
  were receding from the earth
• the velocity of recession was directly
  proportional to the distance of the galaxy

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Redshift Data for 5 Representative Galaxies
54 MLy
Nearby galaxies are moving away from us slowly,
and more distant galaxies are rushing away from
us much more rapidly. These observations lead
us to an inescapable conclusionour universe is
expanding.
674 MLy
988 MLy
1.75 BLy
3.053 BLy
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This proportionality relationship is known as
Hubbles Law and is one of the most significant
results ever made in astrophysics
The velocity calculation (non-relativistic
speeds) is quite simple
?? v ? c
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Hubbles Original Data
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Some of the Latest Hubbles Law Data - based on
distant Supernova Measurements (1998)
Data gives a value of H0 of 64 km/sec per Mpc
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• Hubbles work was experimental confirmation of
  the theoretical predictions of General Relativity
• the universe was expanding
• the expansion was isotropic (same in all
  directions)
• Einstein visited Hubbles lab and was convinced
  his results were correctdropped cosmological
  constant from his equations.

This is known as the Cosmological Red Shift it is
space-time itself that expands and NOT the
objects in it
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The Origin of the Redshift..
A light wave traveling through an expanding
universe stretches, that is, its wavelength
increases. A redshift caused by the expansion of
the universe is properly called a cosmological
redshift. Doppler shifts are caused by an
objects motion through space, whereas a
cosmological redshift is caused by the expansion
of space.
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Big-Bang

• Once Hubbles Law was established
• simple matter to run the expansion backwards and
  conclude that all galaxies were originally at
  same point in space-time
• in fact all matter! the universe itself!, and
  space and time originated at this point
• point in space-time at which the universe began
  is known as the Big-Bang

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Age of Universe

• Since Hubbles Law can be written
• velocity of recession (constant) x distance
• the constant is Hubbles Constant H0
• i.e. v (H0 )(d)
• Running the expansion backwards
• H0 velocity/distance
• 1/H0 distance/velocity time
• the time since the expansion began, i.e. the
  age of the universe

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• Using a value of H0 of 75 km/sec per megaparsec
  or about 24 km/sec per million light years gives
  a time of
• about 13 x 109 or 13 billion years

The actual value of Hubbles Constant was subject
to intense debate with values as high as 100
km/sec/Mpc and as low as 50 km/sec/Mpc
advocated. this gave ages of universe between
about 9 to 17 billion years
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Over time most of the data presented seemed to
converge to a value of 65 - 75 km/sec/Mpc, with
the higher values favored. Well see the present
(Confirmed) value later.
This gives a Hubble Age of about 12 - 13 Billion
years.
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Observable Universe

• As the universe expands, looking out in distance
  is thus equivalent to looking back in time
• a telescope is a sort of time machine
• The observable limit of the universe is the
  distance that light could have traveled since the
  beginning of the universe
• for value of 75 km/sec/Mpc this is 13 Bly

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The Observable Universe
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Objections to the Big-Bang Universe

• Many astronomers did not accept the idea of a
  dynamic, expanding universe By far the majority
  of scientists knew the universe was eternal.
• objections were primarily philosophical
• Big-bang implies an origin
• An eternal universe was desirable
• An eternal universe was simpler
• Plausible alternative presented was the
  Steady-State universe

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Steady-State theory
Fred Hoyle (originator of the term big-bang!),
Thomas Gold, and Hermann Bondi Could explain
expansion and keep an eternal universe with no
origin by allowing matter to be created at a rate
to keep density of universe constant
This required violating the Law of Conservation
of Energy
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Steady State Universe
Steady State Universe
Enough matter appears to keep average density
constant
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Violation of conservation of energy would be
small - less than 1 hydrogen atom per cubic
meter per 50 million years Much too small to
observe!
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Cosmic Microwave Background

• 1946 Physicists Ralph Alpher and George Gamov
  worked on nucleosynthesis of the elements in a
  big-bang
• disc. there should be a very cool residual
  radiation left over from the Big-Bang
• this diffuse radiation should be a blackbody
  radiation at about 5 K

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??? paper
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The energy radiated by a Blackbody takes a
special form when the relative brightness (or
strength) of the radiation is graphed as a
function of the wavelength
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1964-65 Bell Labs scientists Arno Penzias
Robert Wilson were working on a microwave horn
antenna for satellite communication
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Soviet Sputnik 1 was launched on Oct. 4, 1957
US Vanguard program, run by Navy attempted a
launch TV3 on Dec. 6, 1957 Came to be known as
kaputnik, flopnik Stayputnik
ABMA, under Werner von Braun took 84 days to
modify ICBM missile to launch Explorer 1 on Jan
8, 1958 Vanguard successfully launched Vanguard 1
Mar. 17, 1958 1st solar powered satellite (still
in orbit)
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With antenna set at 7.35 cm (4080 MHz) based on f
c/?

• Calibrated antenna to eliminate noise
• far from any galactic radio emissions
• kept getting peculiar static
• const regardless of time of day, season of year,
  direction in the sky

• recalibrated antenna
• cooled their detectors
• removed nesting pigeons from horn
• cleaned antenna
• could not eliminate the static

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Contacted a group at Princeton University who
were working on a design for a system to detect
the residual radiation

• Realized they were seeing this residual radiation
  remnant from the Big-Bang
• Cosmic Microwave Background Radiation
• If a blackbody curve is assumed
• 7.35 cm corresponds to 3.5 Kelvin
• 1976 Penzias Wilson received a Nobel Prize

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• Very little of the 3 K background radiation can
  penetrate the atmosphere
• difficult to measure radiation curve
• used balloons, rockets, aircraft, etc.

• 1989 NASA launched the Cosmic Background Explorer
  (COBE) satellite to measure this radiation

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Cosmic Background Explorer (COBE) Satellite
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Blackbody Spectrum of COBE Satellite and fit to a
2.73 K Curve
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• Cosmic Background Radiation was unexplainable by
  any reasonable means in a steady-state universe
• death blow to that theory

Currently only variations of Big-Bang cosmologies
are widely accepted COBE data is accurate enough
to measure the motion of the earth relative to
the background radiation
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COBE Dipole Speeding Through the Universe
Credit NASA, COBE, DMR, Four-Year Sky Map
Astronomy Picture of the Day, February 5, 1996
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CMB data where 0 K is black and 3 K is
white Observe the uniformity! 1 part in 10,000
The COBE data has been extensively analyzing
looking for small variations (lt 1 part in 10,000)
in the Cosmic Background Radiation that might
measure the clumpiness at the time the CBR
formed.
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30 mK
A map of the brightness of the cosmic microwave
background made by the cosmic background explorer
(COBE) satellite. Notice the patchiness of the
brightness. Each pink patch may represent a
"lump" of matter from which groups of galaxies
ultimately grew. The patches were approximately
one half billion light years across when they
emitted the radiation. (NASA GSFC and the COBE
Science Working Group.)
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Big-Bang Cosmologies

• The only commonly accepted cosmologies to date
  are some form of big bang
• Standard Big Bang only model until 1980s
• There are problems with all big bang models and
  especially with the standard model

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Problems with the Standard Model

• The very tiny variations in the background
  radiation seen by COBE imply that all parts of
  the universe are at equilibrium
• variations in BB temperature lt 1 part in 10,000
• how can this uniformity exist?
• opposite sides of universe 26 Bly apart, too far
  apart to have been in contact during the lifetime
  of the universe, therefore could not be at same
  temp

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Points A and B are at least 26 Billion light
years apart! How could they be in thermal
equilibrium if they could never have been in
contact within the age of the universe (13By)?
Horizon Problem
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Flatness Problem

• In standard big bang models, current flatness of
  universe is a problem
• today universe is VERY flat
• Requires a density during initial stages of big
  bang with a density within 25 decimal places of
  the critical density
• This is highly unlikely!!

The figure above shows scale factor a(t) for
three models with three different densities at a
time 1 nS after the Big Bang. The black curve
shows a critical density case that matches the
WMAP-based concordance model, which has density
447,225,917,218,507,401,284,016 gm/cc at 1 ns
after the Big Bang. Adding only 0.2 gm/cc to this
447 sextillion gm/cc causes the Big Crunch to be
right now! Taking away 0.2 gm/cc universe is too
diffuse
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• One solution to these problems is called the
  inflationary universe

as universe developed from big-bang it was
initially extremely small - so all parts were in
contact -early in life of universe it experienced
an inflationary epoch where universe
suddenly ballooned to billions of times its
original size -all parts of universe were in
thermal contact before inflation, so BB temps
are similar
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The Inflationary Model
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Inflation solves flatness problem

• Newborn universe (before inflation) could have
  been highly curved
• inflation expands the size of universe so much (
  about 1050 times), that any curvature left is too
  small to see today
• consider how earth looks flat

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After Inflation - Universe Looks Flat
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Foundations of Big Bang Cosmology
The Big Bang model of cosmology rests on two key
ideas that date back to the early 20th century
General Relativity and the Cosmological
Principle.
By assuming that the matter in the universe is
distributed uniformly on the largest scales, one
can use General Relativity to compute the
corresponding gravitational effects of that
matter. Since gravity is a property of space-time
in General Relativity, this is equivalent to
computing the dynamics of space-time itself. The
story unfolds as follows
recall the COBE CMB plot at 1 in 10,000 level
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This assumption is being tested continuously as
we actually observe the distribution of galaxies
on ever larger scales.
The accompanying picture shows how uniform the
distribution of measured galaxies is over a 30
swath of the sky. In addition the cosmic
microwave background radiation , the remnant heat
from the Big Bang, has a temperature which is
highly uniform over the entire sky. This fact
strongly supports the notion that the gas which
emitted this radiation long ago was very
uniformly distributed.
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Given the assumption that the matter in the
universe is homogeneous and isotropic (The
Cosmological Principle) it can be shown that the
corresponding distortion of space-time (due to
the gravitational effects of this matter) can
only have one of three forms, as shown in the
picture at left.
It can be "positively" curved like the surface of
a ball and finite in extent it can be
"negatively" curved like a saddle and infinite in
extent or it can be "flat" and infinite in
extent - our "ordinary" conception of space
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Matter plays a central role in cosmology. It
turns out that the average density of matter
uniquely determines the geometry of the universe.
If the density of matter is less than the
so-called critical density, the universe is
open and infinite. is greater than the critical
density the universe is closed and finite.
just equals the critical density, the universe
is flat, but still presumably infinite.
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The value of the critical density 6x10-27 kg/m3
is very small it corresponds to roughly 6
hydrogen atoms per cubic meter, an astonishingly
good vacuum by terrestrial standards!
Therefore one of the key scientific questions in
cosmology today is what is the average density
of matter in our universe? While the answer is
not yet known for certain, it appears to be
tantalizingly close to the critical density.
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Given a law of gravity and an assumption about
how the matter is distributed, the next step is
to work out the dynamics of the universe - how
space and the matter in it evolves with time.
The details depend on some further information
about the matter in the universe, namely its
density (mass per unit volume) and its pressure
(force it exerts per unit area), but the generic
picture that emerges is that the universe started
from a very small volume, an event later dubbed
the Big Bang, with an initial expansion rate.
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For the most part this rate of expansion has been
slowing down (decelerating) ever since due to the
gravitational pull of the matter on itself.

• A key question for the fate of the universe is
  whether or not the pull of gravity is strong
  enough to ultimately reverse the expansion and
  cause the universe to collapse back on itself.
• In fact, recent observations have raised the
  possibility that the expansion of the universe
  might in fact be speeding up (accelerating),
  raising the possibility that the evolution of the
  universe is now dominated by a bizarre form of
  matter which has a negative pressure

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To this point, the only assumption we have made
about the universe is that its matter is
distributed homogeneously and isotropically on
large scales.
There are a number of free parameters in all Big
Bang models that must be fixed by observations of
our universe. The most important ones are 1.
the geometry of the universe (open, flat or
closed) 2. the present expansion rate (the
Hubble constant)
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3. the overall course of expansion, past and
future, which is determined by the fractional
density of the different types of matter in the
universe.
Note that the present age of the universe follows
from the expansion history and present expansion
rate.
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Definitions of terms
Radiation composed of massless or nearly
massless particles that move at the speed of
light. Known examples include photons (light) and
neutrinos. This form of matter is characterized
by having a large positive pressure.
Baryonic matter this is "ordinary matter"
composed primarily of protons, neutrons and
electrons. This form of matter has essentially no
pressure of cosmological importance.
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Dark matter this generally refers to "exotic"
non-baryonic matter that interacts only weakly
with ordinary matter. While no such matter has
ever been directly observed in the laboratory,
its existence has long been suspected for various
reasons. This form of matter also has no
cosmologically significant pressure
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Dark energy this is a truly bizarre form of
matter, or perhaps a property of the vacuum
itself, that is characterized by a large,
negative pressure. This is the only form of
matter that can cause the expansion of the
universe to accelerate, or speed up.
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Galaxy Rotation Curves
If we measure the rotation speeds of the galaxy
as a function of distance from the center, we
have a galaxy rotation curve.
Based on the visible matter we can see in our
galaxy, the orbital speed should fall off in the
outer edges of the galaxy
Observational evidence shows this does not happen!
This is evidence of Dark Matter
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Rotation of the Milky Way
A
B
C
3 possibilities 1 galaxy rotates like a solid
disk (B) 2 Orbits obey Keplers laws, speeds
at large orbits are dramatically slower (C) 3
What we actually see (A), speeds are nearly the
same for small and large orbits
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The Galaxy and Its Dark Matter
30 kiloparsecs
The dark matter in our Galaxy seems to form a
spherical halo whose center is at the center of
the visible Galaxy. The extent of the dark
matter halo is unknown, but its diameter is at
least 100 kiloparsecs or 326,000 light years.
The total mass of the dark matter halo is at
least 10 times the combined mass of all of the
stars, dust, gas, and planets in the Milky Way.
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What is dark matter?
Speculations MACHOS (massive compact halo
objects) Brown dwarfs, white dwarfs, black holes
(50) These are searched for via gravitational
lensing.
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WIMPS weakly interacting massive particles
Theoretical particles that have been suggested
but currently none have ever been detected
The existence of dark matter is well
established since its gravitational effects are
easily seen (not only in our galaxy, but also in
large scale structure of the universe) However,
what dark matter is, actually is unknown!
One of the central challenges in cosmology today
is to determine the relative and total densities
(energy per unit volume) in each of these forms
of matter, since this is essential to
understanding the evolution and ultimate fate of
our universe.
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Matter created from energy

• in first few minutes of big-bang there was enough
  energy to create (via a process like
  pair-production)
• all the hydrogen
• most of the helium
• trace amounts of lithium
• all other elements produced via stellar evolution
  and death

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Pair Production particle
annihilation (particle-antiparticle pair)
(photons created)
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Conversion of Energy into Matter (paths are
bent due to a magnetic field in the chamber
gamma ray photon creates an electron-positron
pair in a bubble chamber
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Radiation Matter Eras of Universe

• first 300,000 years was Radiation Era
• universe was shimmering sea of high energy opaque
  plasma
• to much energy to permit protons neutron to
  combine and form atoms
• primordial fireball

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3000 K
Logarithmic scale
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At 300,000 years, temperature of plasma drops to
less than 3000 K and the matter-dominated
universe begins

• not enough energy to prevent protons and
  electrons from combining to form hydrogen
• almost all protons used up in hydrogen gas which
  is transparent
• universe becomes transparent to light (photons)
• escaping photons form the cosmic background
  radiation seen today
• cooled to about 3 K by the present

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Cosmic Background Radiation is Oldest Thing That
Could be Seen in the Universe

• Since universe was opaque before the era of
  recombination at 300,000 years, we cannot
  ever see back beyond this time

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According to the current cosmological models,
what is the destiny of the universe?
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Mass is the main factor!

• For the Universe, total mass is impossible to
  measure, so we use mass density. Critical density
  6.0 x 10-27 kg/m3
• depends on value of H0 (75 km/sec/Mpc)

Gravity is the Dominant Force in Universe

• Gravity pulls back on the expanding universe
• Strength of the pull determines what happens to
  the universe

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Universe can

• expand forever
• expand at a minimal rate
• expand, stop and then re-contract

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Big Crunch
Big Bang
Bang, Bang, Bang
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System or Engine Mechanical Efficiency
Diesel Engine 40
Gasoline Engine 25
Steam Engine 12
Human Body 1
Universe 0.00000001
The reason that the universe would not "bounce"
if it were to contract is that the universe is
extremely inefficient (entropic). In fact, the
universe is so inefficient that the bounce
resulting from the collapse of the universe would
be only 0.00000001 of the original Big Bang (see
table above). Such a small "bounce" would result
in an almost immediate re-collapse of the
universe into one giant black hole for the rest
of eternity. Guth, A.H. and M. Sher. 1983. The
impossibility of a bouncing universe. Nature 302
505-506.
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Curvature of Space-Time

• The value of the mass density of the universe or
  equivalently the deceleration parameter also
  determined which of Friedmanns solutions apply
• i.e. what is the shape of space-time

Ho2 8?G?/3 kc2/R2 ?/3 Friedmanns Eq.
Dark energy
curvature
Matter density
Ho Hubbles Constant G gravitational
constant ? mass density c speed of
light R scale factor ?
cosmological const. k curvature of universe
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? gt ?o spherical curvature density gt critical
value
Angles of triangle gt 180
? ?o flat space density critical value
Angles of triangle 180
? lt ?o hyperbolic curvature densityltcritical value
Angles of triangle lt 180
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Scientifically What is Ultimate Destiny of the
Universe

• Best values of density( ?o ), and H0, and all
  other data indicate too little matter (even
  including estimates of dark matter) to close the
  universe
• In reality WE DO NOT KNOW!
• Universe will expand forever

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Latest results from measurements of distant
supernovae have given rise to a startling
conclusion
The universes expansion has accelerated This is
contrary to the expected result of gravity
gradually slowing the expansion
down Further microwave background studies
seem to confirm the result that the universe
overall is essentially flat...i.e. at critical
density
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Z
Redshift value z ??/??
Latest distant supernova data, black grey lines
represent different values of dark energy
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One possible explanation of these results has
cosmologists re-introducing Einsteins
Cosmological constant which produces a force
partially balancing the attraction of gravity in
the universe as a whole.
In 2003 the WMAP (Wilson Microwave Anisotropy
Probe) group released their results for the first
year of data from the WMAP spacecraft in orbit
about one of the L2 positions in Earths orbit.
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The results presented were spectacular
Many astronomers believe that these results are
the most significant data released since the
discovery of the Microwave Background in 1965.
The detectors on the craft are much more
sensitive and accurate than COBE detectors and
have a much longer life span. It has been taking
data since Sept. 2001
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WMAP data showing fluctuation in the CBR
??? ??
COBE date ? 30 mK
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Comparison of COBE and WMAP data
A map of the brightness of the cosmic microwave
background (CBR) made by the COBE satellite
30 mK
WMAP
WMAP data ??? ??
COBE
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Improvements in CBR measurements over time
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WMAP - The Results! Based on 7 years of data
The Hubble Constant Ho 71 4,-3 km/sec/Mpc Age
of the Universe 13.73 ? 0.12 Billion
years Constituents of the Universe baryonic
(normal) Matter 4.6 ? 0.005 cold dark matter
23.3 ? 0.3 dark energy 72.1 ? 1.1
Significant nos. of stars born 400 million
years after Big Bang
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What We Can See!
We Can Detect its Gravitational Effects
Currently detectable only by acceleration effects
of distant supernovae
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Science never stands still
Planck Data
H0 67.15 ? 1.2 km/sec/Mpc Dark Matter 26.8,
Dark Energy 68.3 Normal matter 4.9
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The basic content of the Universe
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Cosmological parameters
6-parameters model
Parameter 2013 uncertainty (PlanckWP) Expected 2014 (Planck TP)
Baryon density today ?bh2 0.00028 0.00013
Cold dark matter density today ?ch2 0.0027 0.0010
Thomson scattering optical depth ? 0.013 0.0042
Hubble constant km/s/Mpc H0 1.2 0.53
Scalar spectrum power-law index nS 0.007 0.0031
Constraints on other parameters
Parameter 2013 uncertainty (PlanckWP) Expected 2014 (Planck TP)
Effective number of neutrino species Neff 0.42 0.18
Fraction of baryonic mass in helium Yp 0.035 0.010
Dark energy equation of state w 0.32 0.20
Varying fine-structure constant ?/?0 0.0043 0.0018
? Expected reduction in error bars by factors of
2 or more
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Recombination era began 380,000 years after the
Big Bang
The universe is perfectly flat Not enough matter
to close the universe - it will expand
forever Polarization of the CBR implies inflation
models Dark energy results support a Cosmological
constant term rather than quintesence
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What IS the destiny of the Universe?

• We DO KNOW!
• at some point God will pull the plug!
• Universe will cease to exist
• Col. 116-17 (NASB)
• For in him all things were created, both in
  heaven and on earth, visible and invisible
  ............And he is before all things, and in
  Him all things hold together

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And that of course will be the..
THE END For temporal things!!