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Cosmology

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Cosmology Explaining the Universe An Illustration Fitting a theory to a set of observations is much like fitting a curve through a set of data points. – PowerPoint PPT presentation

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Title: Cosmology


1
Cosmology Explaining the Universe
2
The UniverseA Wonderful Creation
3
The Planets
4
Helix Nebula
NGC 7293 - The closest planetary nebula, gas
expelled from a bright central star (450 ly)
5
A Spiral Galaxy
M81 - 12 million ly
6
Sombrero galaxy
M104 A edge-on spiral, the first galaxy found
with a large red-shift (1000 km/s), 50 million
ly.
7
Colliding galaxies
Stefans Quintet (Arp 319) consists of 5
interacting galaxies, 345 million ly.
8
Galaxies at the end of the universe
The Hubble Ultra Deep Field (HUDF), a
million-second-long exposure (2004) contains
10,000 galaxies in a patch of sky one-tenth the
diameter of the Moon.
9
What Is Cosmology?
  • ? The science of the universe as a whole
  • ? The object is to describe and explain the
    universe
  • Recent advances (e.g., Hubble telescope) have
    yielded a vast collection of observations
  • We try to explain the data in terms of
    cosmological models

10
Biblical Cosmology?
Does Genesis 1 teaches erroneous ancient
cosmology?

.
11
Platos Cosmology (400 BC)
A simplified representation of reality Note the
five elements Circular motion reflects eternal
perfection
12
Medieval Cosmology
Models may incorporate theological and
philosophical beliefs. Note heaven beyond the
stars
13
Dantes Cosmology
Note purgatory and the 9 levels of hell
14
Retrograde Motion - Mars
Explaining the motion of planets requires a more
sophisticated model
15
Epicycles
An epicycle reproduces retrograde motion within
the constraint of circular motion.
16
Epicycles On Epicycles
Adding enough epicycles can attain any desired
accuracy, like Fourier Series
Ptolemy models are useful fictions, aiming at
accuracy and simplicity
17
Uses of Cosmological Models
  • A simplified, qualitative representation of
    reality, reflecting philosophical and theological
    truths (Plato, Dante)
  • 2. A simplified set of mathematical equations,
    yielding quantitative accuracy in calculation
    prediction, saving the appearances (Ptolemy).

18
Copernicus Model
Is a model a useful fiction or a representation
of reality?
19
Tycho Brahes Model
Both models are observationally equivalent. Which
is the true one?
20
Modeling Reality
A cosmological model bridges the gap between
ones conception of reality and appearances, thus
strengthening the case for that conception of
reality. Copernicus was not widely accepted
until his model was tied to a physical model,
after 1650 (Descartes, Newton). Relativity gives
Copernican and Tychonian models equal physical
support. So how do we choose? What does
absolute motion mean?
21
Naturalist Origins The Big Bang
22
Observational Support for Big Bang
1. Galactic red-shifts 2. Relative abundances
(75 H, 24 He) 3. Micro-wave background
radiation
23
Difficulties with Cosmology
? Only one universe cant compare with similar
objects ? Can observe only from one position at
one time ? Can observe only emitted
radiation ? Distant objects are hard to
distinguish from background ? Distances are
hard to measure ? Conditions in early
universe cant be reproduced in laboratories
24
Assumptions in Big Bang Cosmology
? Local laws of physics hold universally ?
General Relativity ? Theoretical high
energy particle physics ? Materialism
everything is derived from matter ? No
non-material causes
25
Problems of Verification
? Untestability of First Kind (inherently
untestable) Cant observe anything before
300,000 yr after BB Cant observe extra
dimensions Cant reproduce high energy to
confirm hypothetical entities in particle
physics ? Untestability of Second Kind
(effectively untestable) standard model of
particle physics has gt20 adjustable parameters,
etc.
26
Big Bang Problems
? Old galaxies at high red-shifts ? No time to
form huge structures of galaxies ? Horizon
problem uniform radiation implies mixing ? Some
primordial stars have much heavy metal ?
According to some cosmologists, energy is not
conserved The conclusion, whether
we like it or not, is obvious energy in the
universe is not conserved. The conservation of
energy principle serves us well in all sciences
except cosmology. (Harrison, Cosmology) ?
Cosmological constant should be much larger than
observed (off by 10120) ? Anomalous
quantized red-shifts ? Mysterious missing mass
dark energy
27
Saving the Theory
? To save big bang cosmology from falsification
(the horizon problem) inflation was invented. ?
But the observed mass of the universe is only a
few percent of that predicted by inflation. ? To
save inflation, the missing mass was postulated
to be unobservable dark matter. ? But
nucleo-synthesis cant produce much more normal
matter than is observed. ? To save dark matter
esoteric new forms of matter are postulated, none
as yet observed... ? And so on...
28
Making Models Fit Reality
Any statement can be held true come what may, if
we make drastic enough adjustments elsewhere in
the system. The totality of our knowledge, from
the most casual matters of history to the
profoundest laws of atomic physics, is a man-made
fabric which impinges on experience only along
the edges. Willard Van Orman Quine
The Duhem-Quine Thesis We can construct a model
with any given feature, if we make drastic enough
changes elsewhere in the model.
29
Observational Fact - Red Shifts of Galaxies
? Lines in light spectra from galaxies are
shifted to the red
? The amount of red shift is proportional to
distance
30
Do Red shifts Support the Big Bang?
? Red shifts would be expected if galaxies are
moving away from us
? Red shifts are interpreted as being caused by
the expansion of space
31
Data Under-determine Theory
Galactic red-shifts could be due to ? expanding
space (big bang) ? motion through space ?
gravity ? decreasing speed of light ?
shrinking atoms ? increasing mass of
particles ? tired light
32
Alternative Cosmologies
? Beginningless Big Bang Cosmology (Gamow,
Linde) ? Meta-Galaxy (Alfven) ? Spherically
symmetric ? Static Cosmologies (Ellis, Arp,
Crawford, Troitski)
33
Biblical Cosmology
Goals 1. Critique non-biblical
cosmologies Big bang anomalies Evidence of
recent creation 2. Explain reality within a
Biblical framework
34
Biblical Cosmology - Origins
Main Challenge Star-light in a big
universe Possible Strategies ? Instrumentalism
theories just useful fictions (G. Clark) ?
Different clock rates (Humphries, Hartnett) ?
Variable speed of light (Setterfield) ?
Illusionary History (Tipler Multiple black
holes) ? Mature Creation (Philip Gosse)
35
Different Clock Rates
? Russell Humphreys (1994) Starlight and Time
white-hole cosmology earth near center -
problem no actual time dilation or blue
shifts ? John Hartnett (2007) Starlight,
Time and the New Physics - 5-d cosmology (time,
space, speed) - earth near center - problem no
detailed calculations, novel physics.
36
Different Clock Rates
? These models are ad hoc and have not been
worked out in detail. They still require mature
creation at least for Sun and nearby stars. They
void much astronomical evidence for young
universe. ? You could get almost the same
effect by postulating that the rotation of the
earth was slower for first 3-4 days, except for
the problem of vegetation on Day 3.
37
Variable Speed of Light
? C Varies with time Barry Setterfield c was
infinite at creation - can explain also rapid
radio-active decay in past - evidence for cdk
over last 300 hundred years dubious - light from
distant galaxies should still reflect large c in
doppler shifts, etc. ? C Varies with
position - c is very large far from earth. - c
is very large in weak gravitational fields. ? C
Varies with direction infinite towards
earth -Jason Lisle (Anisotropic synchrony,
Answers Research Journal, Sept. 2010)
38
Illusory History--Multiple Black Holes
Cosmologist Frank Tipler It is thought to be
impossible to construct a falsifiable theory
consistent with the thousands of observations
indicating an age of billions of years, but which
holds that the Universe is only a few thousand
years old I consider such a view to be a slur
on the ingenuity of theoretical physicists we
can construct a falsifiable theory with any
characteristics you care to name. (How to
Construct a Falsifiable Theory in Which the
Universe Came into Being Several Thousand Years
Ago,) A few thousand years ago the universe was
dense with black holes, causing illusory
histories.
39
Mature Creation The Sun
Most of the previous creationist cosmologies
still need some degree of mature creation for
Earth, Sun, nearby stars, Galaxy.
The Sun created in mature, fully functioning
form, would include photons at its surface that
would appear to have a 100,000 year history
behind them.
40
Mature Creation - The Galaxy
The Galaxy, created in mature functional form
would include gravitons and photons that appear
to have come from distant parts of the Galaxy
M81 - 12 million ly (95,000 ly across)
41
Mature Creation A Cluster of Galaxies
A cluster of galaxies, created in mature
functional form would include gravitons and
photons that appear to have come from distant
parts of the cluster. Hence, it is natural that
the universe, created in mature form, would
include photons that appear to have a long
history.
The Coma Cluster 321 million ly away
42
Mature Creation and Science
A modern cosmologist who is also a theologian
with strict fundamentalist views could construct
a universe model which began 6000 years ago and
whose edge was at distance of 6000 light years
A benevolent God could easily arrange the
creation so that suitable radiation was
travelling toward us from the edge of the
universe to give the impression of a vastly older
universe. It would be impossible for any
scientist on earth to refute this world picture
experimentally or observationally all he could
do would be to disagree with the authors
cosmological premises. (cosmologist George
Ellis)
43
Mature Creation and Science
The theory is free from self-contradiction and is
consistent with all the facts ot experience we
have to explain it certainly does not multiply
hypotheses beyond necessity since it invokes only
one and it is certainly beyond future
refutation. If we are to ask of our concepts
nothing more than that they should correlate our
present experience economically, we must accept
it in preference to any other. Nevertheless, it
is doubtful if a single person does so.
(Herbert Dingle)
44
Would God Deceive Us?
Don Stoner (A New Look at an Old Earth, 1997,
87) Either Gods creation testifies that it is
much older than 10,000 years or God has deceived
us in his creation. Jitse vanderMeer (2009,
Primate ancestors, p.9) If people living
today would have been created by fiat creation
rather than by evolutionary creation, there would
have been no branching pattern unless the Creator
would have wanted us to believe there had been a
history which never actually occurred. Since
the Creator does not deceive us I conclude that
He created us by means of an evolutionary process
thereby giving us a real evolutionary history.
45
Would God Deceive Us?
Rene Descartes (1596-1650) (Meditations on First
Philosophy, III-IV) God is perfect, hence God
cannot deceive. So God would not permit me to be
deceived concerning the truth of those
propositions that seem entirely clear to me,
hence these propositions must be
true. Note These authors do not consider the
converse If God does not deceive, should we not
take Him at His Word?
46
Would God Deceive Us?
Scripture does say that God cannot lie (Titus
12, Heb.618), but these remarks occur in an
explicitly covenantal context meaning that he
cannot lie to believers because he has promised
not to. Scripture specifically says that God
deceives those who are not believers (Ez.149, 2
Thes.211). Therefore God sends them a strong
delusion, so that they may believe what is false,
in order that all may be condemned who did not
believe the truth (2 Thes. 211) Ultimately
all religious deception is traceable to Satan,
the serpent of old . . . who deceives the whole
world (Rev.129).
47
How will the World End?
Big Crunch or whimper OR Return of Jesus
Christ?
Frank Tipler Traditional religion must come to
grips with the fleeting existence of our species
in history. It is our relative insignificance in
time, not space, which is the real challenge
posed by modern cosmology for traditional
religion The universe will last at least another
5 billion yearsAlmost all Christian theologians
adopt a much shorter perspective. This is as
great an error as believing that the universe
was created a few thousand years ago.
48
Will Christ Return?
Hans Kung (The beginning of all things
2007) Biblical miracles are metaphors, not
historical events that break any laws of nature.
(152) It is necessary to warn against
theological fallacies about the end of the world,
as much as fallacies about the beginning of the
world (199). Just as the biblical narratives
of Gods work in creation were taken from the
environment of the time, so too the reports of
Gods final work were taken from contemporary
apocalyptic
49
Parting with Big Bang Cosmology
Any genuine Christian must believe in the
physical return of Christ. This means parting
with secular cosmology at some point (John
Polkinghorne). But if secular cosmology is
unreliable as to the future, why should we
believe it as to the past?
The Last Judgment Michelangelo
50
Reality is More than the Observed
The universe is more than matter ? Spiritual
reality God, angels, demons- can have physical
effects ? Present Heaven a physical place,
nearby, yet normally not seen by us ? Cosmology
applies only to the observed world, a thin shadow
of full reality
51
How Do You Explain?
If the Bible is true how do you light from
distant stars, etc.? ? It is always possible to
construct theories consistent with the
observations and the biblical givens,
particularly if we allow for the possibility of
miracles. ? The truth of the Bible should not
rest on our ability to explain it
scientifically. ? If science cannot easily
explain (Biblical) facts, this just shows the
limitations of human science, particularly
regarding origins.
52
An Illustration
  • Fitting a theory to a set of observations is
    much like fitting a curve through a set of data
    points.

Biblical data
Observations
Simplest theory
Extrapolated point
For example, was there enough water on the
earths surface for the Flood to cover the
mountains?
53
Assessing Creationist Models
Advantages ? Based on Biblical truth ? Show
consistency between Bible and observations
Limits ? Many Biblical models are possible
which one is true? ? Mature creation doesnt
explain observational details ? Limited
apologetic value assessment choice depend on
worldview beliefs. ? Dont tie Bible to any
particular scientific theory
However ? We must consider comprehensive
explanatory power ? Worldviews come as package
deals
54
How do we choose a cosmology?
Worldview beliefs are unavoidable What is the
ultimate reality? Matter Mind - Spirit How do
we know truth? Empiricism through our
senses Rationalism through our reason Theism
through Gods Word
55
Conclusions
  • 1. There is a huge gap between cosmological data
    and theory
  • 2. Cosmology needs presuppositions many are
    unverifiable
  • 3. The same data can be explained by many
    cosmologies
  • 4. Any favored cosmology can be saved by ad hoc
    devices
  • 5. Cosmologies are assessed in terms of ones
    worldview
  • 6. Materialist Biblical cosmology differ on
    origins, future, nature of reality.
  • 7. Biblical cosmology gives meaning to reality,
    purpose to our life and hope for our future
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