The fitness of water for life

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Evidence for design in the universe
Physical sciences
Biological sciences
.
.
.
fine-tuning
anthropic coincidences
habitability
discoverability
intelligibility
physical laws
etc
.
.
.
origin of life
molecular machines
hardware and software of cells
micro and macro evolution
basic charact. of fossil record
etc
Cognitive sciences
.
.
.
mind/brain
consciousness
personhood
free will
etc
Evidence for design in the universe
Physical sciences
Biological sciences
.
.
.
fine-tuning
anthropic coincidences
habitability
discoverability
intelligibility
physical laws
etc
.
.
.
origin of life
molecular machines
hardware and software of cells
micro and macro evolution
basic charact. of fossil record
etc
Cognitive sciences
.
.
.
mind/brain
consciousness
personhood
free will
etc
Sources for further study
The Goldilocks Enigma
Paul Davies
The Fitness of the Cosmos for Life
John D. Barrow et al
Rare Earth
Ward and Brownlee
Nature’s Destiny
Michael Denton
Life’s Solution (Chap 5)
Simon Conway Morris
Why The Universe Is The Way It Is
Hugh Ross
The Privileged Planet Gonzalez and Richards
A Case Against Accident and Self-Organization Dean Overman
The Politically Incorrect Guide to Darwinism and
Intelligent Design (Chap 11)
Jonathan Wells
The anthropic coincidences
There is now broad agreement among physicists and
cosmologists that the universe is in several respects ‘finetuned' for life.
P. Davies Int. J. of Astrobiology 2(2): 115, (2003).
“Over the past three decades, facts such as these drawn
from astrophysics and cosmology have led many
physicists to argue that the cosmos appears to be finely
tuned for life.”
M. Denton, Nature’s Destiny p 10, (1998).
The anthropic coincidences
It is true, for example, that the fine structure constant a has to be close
to 1/137 for carbon atoms to exist, and carbon atoms are required for
us to be here writing about cosmology. However, these arguments
have nothing to do with explaining what physical laws led to this
particular value of a. …
The anthropic principle is an observation, not an explanation. To
believe otherwise is to believe that our emergence at a late date in the
universe is what forced the constants to be set as they are at the
beginning. If you believe that, you are a creationist. …
[Regarding a recent theory by S. Hawking and T. Hertog on this topic]
…it sounds to me a lot like the despised fine-tuning.
B. Richter, Physics Today, Oct 2006 p 8-9.
The anthropic coincidences
Three categories:
i) simple elegant mathematical form that nature
takes
ii) universal constants (19)
iii) initial (or special) conditions
The anthropic coincidences
I.
Fine-tuning of the earth (solar system, galaxy)
II. Fine-tuning of the properties of water and carbon
III. Fine-tuning of the fundamental constituents of the
universe
IV. Fine-tuning of the expansion of the universe
The anthropic coincidences
I.
Fine-tuning of the earth (solar system, galaxy)
II. Fine-tuning of the properties of water and carbon
III. Fine-tuning of the fundamental constituents of the
universe
IV. Fine-tuning of the expansion of the universe
Part I
Fine-tuning of the earth
(solar system, galaxy)
Fine-tuning of the Earth
The Copernican principle vs
the anthropic coincidences
The Copernican principle
"However we are not able to make cosmological models without some
admixture of ideology. In the earliest cosmologies, man placed himself
in a commanding position at the centre of the universe. Since the time of
Copernicus we have been steadily demoted to a medium sized planet
going round a medium sized star on the outer edge of a fairly average
galaxy, which is itself simply one of a local group of galaxies. Indeed we
are now so democratic that we would not claim that our position in
space is specially distinguished in any way. We shall, following Bondi
(1960), call this assumption the Copernican principle.”
Hawking, S.W. and Ellis, G.F.R., The Large Scale Structure of SpaceTime, Cambridge University Press, Cambridge, p. 134, 1973.
Fine-tuning of the Earth
“Most of the Universe is too cold, too hot, too dense, too
vacuous, too dark, too bright, or not composed of the right
elements to support life. … of all the known celestial
bodies, Earth is unique in both its physical properties and
its proven ability to sustain life….”
“From the biased viewpoint of Earthlings, however, it does
appear that Earth is quite a charmed planet.”
P. Ward and D. Brownlee, Rare Earth, 2000, p 37.
Fine-tuning of the Earth
“If some god-like being could be given the opportunity to
plan a sequence of events with the express goal of
duplicating our “Garden of Eden”, that power would face a
formidable task. With the best intentions, but limited by
natural laws and materials, it is unlikely that Earth could
ever be truly replicated. Too many processes in its
formation involved sheer luck.”
P. Ward and D. Brownlee, Rare Earth, 2000, p 37.
What does it take to make a habitable planet?
Isaiah 45:18
For this is what the LORD says - he who created the
heavens, he is God; he who fashioned and made the earth, he
founded it; he did not create it to be empty, but formed it
to be inhabited - he says: I am the LORD and there is no
other.
What does it take to make a habitable planet?
~ 1011 planets in our galaxy
1
1012
1
1
1
1
1
1
x
x
x
x
x
100
100
100
100
100
100
( )( )( )( )( )( ) =
If 6 finely-tuned factors exist, then we have no right to expect another
earth-like planet in the entire galaxy!!
~ 1022 planets in the observable universe
1
1
1
1
1
1
1
1
1
1
1
(100 )x (100 )x(100 )x (100 )x(100 )x (100 )x(100 )x (100 )x (100 )x (100 )x(100 ) =
1
1022
If 11 finely-tuned factors exist, then we have no right to expect another
earth-like planet in the entire observable universe!!
Earth’s orbit around the sun
Freezing and
boiling of
water set
conservative
limits
Earth’s orbit around the sun
“One of Earth’s most basic life-supporting
attributes is indeed its location, its seemingly
ideal distance from the sun.”
Rare Earth, p 16.
“Astrobiologists James Kasting and his
colleagues … estimated in 1993 that the width
of the CHZ is from 0.95 to 1.15 AU.”
(1 AU = distance from the Earth to the Sun)
Rare Earth, p 19.
Orbital characteristics of extra solar planets
circular:
eccentricity = 0
1/10 are circular
The Privileged Planet
pg 95
Earth’s size
“Earth’s size is just about right - not too small that its
gravity was too weak to hold the atmosphere and not so
large that its atmosphere would hold too much atmosphere
including harmful gases …
F. Press and R. Siever, Earth, 1986, p 4. Quoted in
Nature’s Destiny p 92
Needed: Sufficiently large for a sufficiently strong magnetic field
But not too large or highly active tectonic plates
Orbital characteristics of extra solar planets
Nature 470, 2426, 2011
1/200
earth-sized,
in habitable
zone
(Nature 470,
27-29, 2011)
Earth’s tilt about spin axis
“Although our viewpoint
is certainly biased, our
planet’s tilt axis seems to
be “just right”.
Rare Earth, p 224.
+/- 1 deg for several thousand yrs
larger tilt - temperature extremes
smaller tilt - rain not distributed
Privileged Planet, p 5.
Earth’s tilt about spin axis
“Constancy of the tilt angle is a factor that provides long-term
stability of the Earth’s temperature. If the polar tilt axis had
undergone wide deviations from its present value, Earth’s climate
would have been much less hospitable…..
Rare Earth, p 224.
These results show that the situation of the Earth is very peculiar.
The common status for all the terrestrial planets is to have
experienced very large scale chaotic behavior for their obliquity,
which in the case of the Earth and in the absence of the Moon,
may have prevented the appearance of evoluted forms of life. We
owe our exceptional climate stability to an exceptional event the presence of the moon.
Jacques Laskar, quoted in Rare Earth p 224.
The Moon
Just right size and distance from the Earth to
-stabilize tilt
-slow Earth’s rate of rotation
“our moon is somewhat of a freak because of its large size in
comparison to its parent planet.”
Rare Earth p 222.
“Without the moon it is … likely that no birds, redwoods, whales,
trilobites, or other advanced life would ever have graced Earth. …
Although there are dozens of moons in the solar system, the
familiar ghostly white moon that illuminates our night sky is
highly unusual, and its presence played a surprisingly important
role …”
Rare Earth p 222.
The Moon
“We owe our present climate stability to an exceptional event:
the presence of the Moon.”
Jacques Laskar, quoted in Rare Earth p 224.
Produced by a “just right” collision?
“to produce such a massive moon, the impacting body had to be
the right size, it had to impact the right point on the Earth, and
the impact had to have occurred at just the right time in the
Earth’s growth process.”
Rare Earth p 231.
Earth’s atmosphere
“… differs greatly from those of other terrestrial planets,
which range from essentially no atmosphere (Mercury) to a
CO2 atmosphere a hundred times denser (Venus) and a CO2
atmosphere a hundred times less dense (Mars).”
Ward and Brownlee, Rare Earth, p 52.
“It is difficult to see how the actual concentrations of these
gases could be very different from what they are in any
atmosphere supporting a carbon-based biosphere.”
M. Denton, Nature’s Destiny, p 55.
Earth’s atmosphere
Oxygen is essential for the energy generating reactions of
life, its reactivity is fine-tuned.
“Oxygen is basically a very
dangerous reactive substance and is
highly toxic to life at levels above
those normally encountered in
nature. … Oxygen is fit because its
chemical reactivity is attenuated at
ambient temperatures (below 50 oC),
allowing living systems to utilize this
awesome energy source in a
controlled and efficient manner.”
M. Denton, Nature’s Destiny 123,
125
min. pressure is
required to retain
liquid water
M. Denton, Nature’s Destiny
Earth’s atmosphere
Could our atmosphere contain more oxygen and still support
life? No! … the current percentage of oxygen in the
atmosphere, 21 %, is close to the upper limit of safety for
life at ambient temperatures.”
M. Denton, Nature’s Destiny, p 120.
“the present oxygen level is at a point where risk and benefit
nicely balance.”
J. E. Lovelock, Gaia, 1987, p 71.
Earth’s elemental composition
Earth’s elemental composition
number mass
46.6% O
35% Fe
27.7% Si
30% O
8.1% Al
15% Si
5.0% Fe
13% Mg
3.6% Ca
2.4% Ni
2.8% Na
1.1% Ca
2.1% Mg
1.1% Al
Relative abundance of elements in the sun
Earth’s chemical composition
If too much water - all land is covered
0.1% water
“with even twice as much water, Earth would have ended up
as an abyssal planet entirely covered with deep blue water a true “water world” …”
Ward and Brownlee Rare Earth, p 47
“thus the planet’s remarkable mixture of land and oceans is a
balancing act. … This fortuitous combination may be the
most important factor that ultimately made life possible.
Ward and Brownlee Rare Earth, p 53.
If too little water - global temperatures would fluctuate too
much
Ward and Brownlee Rare Earth, p 264
Earth’s elemental composition
“Discovering how Earth acquired its supply of water is one
of the most critical concerns of the new field of astrobiology.
As we pointed out in an earlier chapter, water was not
abundant in the inner regions of the solar system when
planets formed. There was far more water in the outer
regions of the solar system than among the inner planets.
Where did our water come from?”
Still subject of debate, comets - heavy bombardment?
Ward and Brownlee Rare Earth, p 261.
Earth’s elemental composition
“An enigma of Earth’s formation is its composition and particular
location in the solar system…. A grand paradox of terrestrial planets
is that if they form close enough to the star to be in its habitable
zone, they typically end up with very little water and a dearth of
primary life-forming elements such as nitrogen and oxygen,
compared with bodies that formed in the outer solar system. In
other words, the planets that are in the right place, and thus have
warm surfaces, contain only minor amounts of the ingredients
necessary for life”.
“the origin of biogenic elements is a subject of considerable
speculation.”
from “asteroidal and cometary debris” ?
Rare Earth, p 45, 48.
Earth’s elemental composition
If too much water - all land is covered
If too much carbon, CO2 will cause runaway
greenhouse effect
0.05 % carbon
Earth’s elemental composition
If too much water - all land is covered
If too much carbon, CO2 will cause runaway
greenhouse effect
Enough Fe in core for a magnetic field
35 % iron
Earth’s elemental composition
If too much water - all land is covered
If too much carbon, CO2 will cause runaway
greenhouse effect
Enough Fe in core for a sufficient magnetic field
Enough radioactive metals for long-lived furnace
(uranium, thorium, potassium)
Just right composition for thin crust - enables plate
tectonics
Earth’s elemental composition
“… the Earth’s interior is a delicately balanced heat engine fueled by
radioactivity … were it running too slowly … the continents might not
have evolved to their present form… Iron may never have melted and
sunk to the liquid core, and the magnetic field would never have
developed…. If there had been more radioactive fuel, and therefore a
faster running engine, volcanic dust would have blotted out the Sun, the
atmosphere would have been oppressively dense, and the surface would
have been racked by daily earthquakes and volcanic explosions.”
F. Press and R. Siever, Earth, 1986, p 4.
radioactive elements:
uranium 238 – 0.0004% (by mass)
thorium 232 – 0.0012%
potassium 40 – 0.0028%
Earth’s cycles
Hydrological cycle
Plate tectonics (earth, but nowhere else in solar system)
Ensure the physical and chemical constancy of our environment
-regulates greenhouse gases
-builds continents
-global thermostat (5 C - 40 C)
-magnetic field (T difference across core, convection cells)
“Like two gigantic cogwheels engineered to fit perfectly together, these
two great cycles have turned together in perfect unison … ensuring the
continual turnover and essential recycling of the vital elements of life.”
M. Denton, Nature’s Destiny, p 84.
The sun
The sun
(G-type, main sequence)
Just-right size:
bigger - hotter, burns faster, more erratic
smaller - cooler, habitable zone closer in, its
gravity would slow a planet’s
rotation too much
5% of stars in our galaxy are similar to our sun
80% are red dwarf stars (highly unlikely to support habitable planets)
main sequence stars:
fusing hydrogen to
helium
The sun
Temp range of stars:
The sun:
30,000 oC - 1000 oC
5500 oC
The sun
M-type stars - thousand or million times more active ( flares) than sun
The sun
for photochemistry:
< 0.3 too energetic
> 0.7 too weak
“That the radiation from the
sun… should be concentrated
into a miniscule band of the
electromagnetic spectrum
which provides precisely the
radiation required to maintain
life on earth is a very
remarkable coincidence
described as ‘staggering’ by
Ian Campbell in Energy and
Atmosphere.”
M. Denton, Nature’s Destiny
The sun
Temp range of stars:
30,000 oC - 1000 oC
for photochemistry:
< 0.3 too energetic
> 0.7 too weak
peak range of stars:
0.1 um - 2.3 um
The sun: 5500 oC
The sun
From “Nature’s Destiny”, by M. Denton
The sun
“We should indeed be
awed and
staggered…. It is as
if a cardplayer had
drawn precisely the
same card on four
occasions from a deck
of 1025.”
M. Denton, Nature’s
Destiny
Jupiter and outer planets
Jupiter: just-right size and location:
Jupiter and outer planets
Jupiter: just-right size and location:
“without a large planet positioned precisely where Jupiter is, the
earth would have been struck a thousand times more frequently in
the past by comets and meteors and other interplanetary debris.”
“…we wouldn’t be around to study the solar system.”
G. W. Wetherill, Nature 1995, 373: 470; Discover 1993, p 15.
However, if Jupiter were too large, or too close, it would perturb
Earth’s orbit.
Jupiter and outer planets
Gas giants: Jupiter, Saturn, Uranus, Neptune
Orbits:
-on the same horizontal plane
-almost circular (avg eccentricity = 0.06 Priv. Planet p 96)
Slight deviations
would be catastrophic
for Earth
Our position in the Milky Way
Our position in the Milky Way
Moreover, the Sun's circular orbit about the galactic center is just right;
through a combination of factors it manages to keep out of the way of
the Galaxy's dangerous spiral arms. Our solar system is also far enough
away from the galactic center to not have to worry about disruptive
gravitational forces or too much radiation. …
More than 95 percent of stars in the Galaxy, says Gonzalez, wouldn't be
able to support habitable planets simply because their rotation is not
synchronized with the rotation of the galaxy's spiral arms. Add all the
other factors involved in keeping a solar system habitable, and it seems
that the odds of finding another solar system in a Galactic Habitable
Zone are close to impossible.
Galactic Habitable Zones, Astrobiology Magazine, May 18, 2001
Our galaxy
A spiral galaxy (only 6% of all galaxies)
elliptical - little new star formation
- abundance of heavy elements is low
- existence of planets is doubtful
Rare Earth p 29.
What does it take to make a habitable planet?
~ 1011 planets in our galaxy
1
1012
1
1
1
1
1
1
x
x
x
x
x
100
100
100
100
100
100
( )( )( )( )( )( ) =
If 6 finely-tuned factors exist, then we have no right to expect another
earth-like planet in the entire galaxy!!
1
4
1
1
1
1
1
1
1
1
(200 ) x (100 ) x (100 ) x ( 2 ) x ( 10 ) x (100 ) x (100 ) x (100 ) x (100 ) x (100 ) x
earth-sized,
in habitable zone
(Nature 470,
27-29, 2011)
G-type,
galactic rocky
main
habitable
sequence
zone
star
(Icarus 152
185-200,
2001; the
physics
arXiv blog)
circular
orbit
magnetic
right
amount field(liqui
of water d iron
core)
large
moon,
close
….
right
plate
tectonics atmosphere
(venus and
mars)
What does it take to make a habitable planet?
~ 1022 planets in the observable universe
1
1
1
1
1
1
1
1
1
1
1
x
x
x
x
x
x
x
x
x
x
100
100
100
100
100
100
100
100
100
100
100
( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( )=
1
1022
If 11 finely-tuned factors exist, then we have no right to expect
another earth -like planet in the entire observable universe!!
Creation as Science, Hugh
Ross, p 179
See also Why The
Universe Is The Way It Is,
Hugh Ross, pg 122-123
hundreds of
such factors
exist!
Number has increased
as scientific knowledge
has progressed!
What does it take to make a habitable planet?
Isaiah 45:18
For this is what the LORD says - he who created the
heavens, he is God; he who fashioned and made the earth, he
founded it; he did not create it to be empty, but formed it
to be inhabited - he says: I am the LORD and there is no
other.
Part II
Fine-tuning of the properties of water
and carbon
The fitness of water for life
Chemical/biological properties:
versatile solvent: polar, ionic compounds dissolve
nonpolar compounds do not
(allows proteins to fold, lipids to form membranes)
Reactant or product in nearly all biochemical/biophysical
reactions:
photosynthesis: H2O + CO2 + sunlight
oxidation: glucose + O2
O2 and glucose
CO2 + H2O + energy
synthesis & degradation of: proteins, lipids, nucleic acids carbohydrates
high proton conductance:
The fitness of water for life
Thermal properties
1. Anomalous expansion below 4 C
2. Density of ice < density of liquid water
“ … both are mutually adapted toward the end of preserving
bodies of liquid water on a planetary surface.”
Nature’s Destiny p 25.
3. High latent heat of freezing or evaporation
4. High heat capacity of liquid water
5. High thermal conductivity of water
6. Low thermal conductivity of ice and snow
The fitness of water for life
Thermal properties
1. Anomalous expansion below 4 C
2. Density of ice < density of liquid water
density of water at 0 oC = 1.0 g/ml
density of ice at 0 oC = 0.92 g/ml
without these two properties “most of the water on the earth would be permanently frozen
into vast beds of ice at the bottom of the oceans”. M. Denton, Nature’s Destiny, pg 28
The fitness of water for life
Thermal properties
1. Anomalous expansion below 4 C
2. Density of ice < density of liquid water
3. High latent heat of freezing or evaporation
4. High heat capacity of liquid water
5. High thermal conductivity of water
6. Low thermal conductivity of ice and snow
The fitness of water for life
Temperature regulation:
High heat capacity of liquid water
High thermal conductivity of water
High latent heat of evaporation
100 kg man runs 10 miles in one hr, generates 1000 kcal of heat
no heat loss - T would increase by 10 oC
if made of ethanol - T would increase by 20 oC
“not one or two, not most, but all the thermal properties of water are
mutually adaptive not only for the maintenance of thermal stability on
a planetary scale, but also for the buffering of individual macroscopic
life forms against sudden temperature changes….
No other liquid
is known which can even remotely approach the fitness of water for
temperature regulation. “
Nature’s Destiny pg 29, 45
The fitness of water for life
Surface tension
water: 72 mN/m, most organic liquids: 20-40 mN/m
-high surface tension draws water through soil, roots, and branches
-assists in the processes of weathering of rocks, formation of soils
The fitness of water for life
Viscosity (exceptionally low)
diffusion - import. for unicellular organisms and individual cells to
gain nutrients
circulatory system:
no active cell can survive in a mammal unless it is within
~ 50 um of a capillary
very small capillaries are needed ~ 3-5 um
flow rate ~ 1/viscosity, resist to flow ~ 1/(diameter)4
“if the viscosity of water had been only a few times greater
than it is, pumping blood through a capillary bed would
require enormous pressure and almost any sort of
circulatory system would be unworkable.”
Nature’s Destiny pg 35
The fitness of water for life
Viscosity (exceptionally low)
diffusion - import. for unicellular organisms and individual cells to
gain nutrients
circulatory system:
“It seems then that the viscosity of water must be very
close to what it is to be a fit medium for life. … If it was much
higher, diffusion would be prohibitively slow, and while very simple
cell systems might be possible, large complex metabolically active
orgnaisms would not. No conceivable set of compensatory
changes - increasing the number or diameter of the capillaries,
increasing the flow rate or decreasing average cell size, etc could be engineered to make mammalian life possible.”
Nature’s Destiny pg 35
The fitness of water for life
chemical/biological properties
thermal properties
surface tension
viscosity
etc
“the evidence reviewed in this chapter indicates that water is uniquely and
ideally adapted to serve as the fluid medium for life on earth in not just
one, or many, but in every single one of its known physical and chemical
characteristics.”
Nature’s Destiny p 25.
The fitness of water for life
chemical/biological properties
thermal properties
surface tension
viscosity
etc
“It is striking that so many eccentricities should occur together in one
substance.”
Frank Stillinger, Science 209, p 451 (1980).
The fitness of water for life
Ammonia?
Heat of vaporization only 1/2 that of water
Surface tension only 1/3 that of water
Much weaker hydrogen bonds: far less able to concentrate nonpolar
molecules by hydrophobic effect
The fitness of carbon
"How is it that common elements such as carbon, nitrogen, and oxygen
happened to have just the right kind of atomic structure that they needed
to combine to make the molecules upon which life depends? It is
almost as though the universe had been consciously designed."
Richard Morris, The Fate of the Universe, 1982, 155.
"Without such accidents water could not exist as a liquid, chains of
carbon atoms could not form complex organic molecules, and hydrogen
atoms could not form breakable bridges between molecules"
Freeman Dyson, Disturbing the Universe,1979, 393.
The fitness of carbon
”The total number and diversity of possible chemical structures that may
be constructed out of carbon, oxygen, hydrogen, and nitrogen is virtually
unlimited. Almost any imaginable chemical shape and chemical
property can be derived.
The reason for the unique diversity and number of carbon compounds
lies in certain unique characteristics of the carbon atom …
…It is the only element which could occupy such a position….
…universal chemical constructor kit …
It is as if from the very moment of creation the biochemistry of life was
already preordained in the atom-building process, as if Nature were
biased to this end from the beginning.”
Michael Denton, Nature’s Destiny, 108.
The fitness of carbon
The fitness of carbon
Metastability of chemical bonds - they do not require much energy
to be activated for covalent chemical reactions
“As in so many respects carbon seems to have the best of both
worlds, combining stability with lability”
However, this metastability is only manifest in a very narrow
temperature range ( -20 C - 120 C).
“a highly suggestive coincidence that the chemical reactivity of the one
great class of compounds, uniquely fit in so many other ways to serve as
the building blocks of life, is of optimal utility for the complex atomic
and molecular manipulations associated with life in precisely that
temperature range - 0 oC to 100 oC - in which water, the one fluid
supremely fit to serve as the matrix for carbon based life forms, exists as
a liquid at sea level on the earth.
Michael Denton, Nature’s Destiny, 108.
The fitness of carbon
Metastability of weak chemical bonds
(hold proteins in folded state)
Remarkably, these weak bonds are also of utility in approximately the same
small temperature range. In fact, weak bonds are even more temperature
sensitive than covalent bonds. Most weak bonds in existing biomolecules
such as proteins are disrupted by increases in temperature which leave
covalent bonds intact.
Michael Denton, Nature’s Destiny, 115.
The fitness of carbon and water
“out of the enormous range of temperatures in the cosmos, there is only
one tiny temperature band in which we have (1) liquid water, (2) a great
plenitude of metastable organic compounds, and (3) weak bonds for
stabilizing the 3-D forms of complex molecules.
Michael Denton, Nature’s Destiny, 116.
Another coincidence??
Part III
Fine-tuning of the fundamental
constituents of the universe
The universe
-particles of matter (energy)
-space-time
-laws of nature
-constants of nature
Huge amount of precision and engineering in all this
(mostly invisible) stuff!
The anthropic coincidences
The universal constants
me,
mass of electron
a,
electromagnetic force constant
mp ,
mass of proton
aS,
strong force constant
mn ,
mass of neutron
aW,
weak force constant
e,
charge of electron and proton
aG,
gravitational force constant
c,
speed of light in vacuum
etc
h,
Planck’s constant
k,
Boltzmann’s constant
The universal constants
Very important recent discovery
The precise values of these constants are critical
for the universe to support life!
-stability of the elements
-ability to form chemical compounds
-types of stars and rates of burning
-etc
The anthropic coincidences
Some important events on this topic:
The Fitness of the Environment
Lawrence Henderson, 1913
The Unreasonable Effectiveness of Mathematics in the
Natural Sciences
Eugene Wigner, 1960
Large Number Coincidences and the Anthropic Principle
in Cosmology
Brandon Carter, 1973
Energy from sun matched with that
needed for photochemistry
for photochemistry:
< 0.3 too energetic
> 0.7 too weak
This occurs because the values of the universal
constants h, c, G, me, mp, e are just right.
Energy from sun matched with that
needed for photochemistry
from Barrow and Tipler, The Anthropic Cosmological Principle
This occurs because the values of the universal
constants h, c, G, me, mp, e are just right.
Many elements are needed for life
The universal constants
Ex. ratio of mass of proton to mass of electron (1,836)
This ratio determines the characteristics of orbits of
electrons about nuclei. If this ratio were slightly
different there would be no chemistry, and no life. S.
Hawking cites this example as one of the many
fundamental numbers in nature, and he says
"The remarkable fact is that the values of these
numbers seem to have been very finely adjusted to
make possible the development of life".
S. Hawking, A Brief History of Time,1988, pg 125.
The universal constants
Ex. ratio of mass of neutron to mass of proton (1.0014)
If protons were slightly heavier than neutrons, “protons
would decay into neutrons .. with disastrous
consequences for life, because without protons there
would be no atoms and no chemistry".
P. Davies, The Goldilocks Enigma,2008, pg 145.
mass of neutron must be greater than mass of proton + electron
The four fundamental forces
rel. strength
Strong nuclear force
Weak nuclear force
Electromagnetic force
Gravitational force
(SF)
(WF)
(EMF)
(GF)
1
10-6
1/137
6 x 10-39
“Slight variations in physical laws such as gravity or electromagnetism
would make life impossible… The necessity to produce life lies at the
center of the universe’s whole machinery and design.”
John Wheeler
The four fundamental forces
rel. strength
Strong nuclear force
Weak nuclear force
Electromagnetic force
Gravitational force
(SF)
(WF)
(EMF)
(GF)
1
10-6
1/137
6 x 10-39
Strong nuclear force - holds nucleus together
If:
SF/EMF x 1.02
SF/EMF x 0.95
no stable hydrogen
few if any elements other than hydrogen
Ward and Brownlee, Rare Earth, 2000.
The four fundamental forces
rel. strength
Strong nuclear force
Weak nuclear force
Electromagnetic force
Gravitational force
(SF)
(WF)
(EMF)
(GF)
1
10-6
1/137
6 x 10-39
"If the strong nuclear force were even 0.3 % stronger or 2% weaker
the universe would never be able to support life."
Barrow and Tipler, Anthropic Cosmological Principle, 318-327,
354-359.
The four fundamental forces
rel. strength
Strong nuclear force
Weak nuclear force
Electromagnetic force
Gravitational force
(SF)
(WF)
(EMF)
(GF)
1
10-6
1/137
6 x 10-39
Weak nuclear force - controls radioactivity
If WF were slightly larger, neutrons would decay into protons faster, and heavy
elements needed for life would not form
If WF were slightly weaker, most hydrogen would have converted into helium
The four fundamental forces
rel. strength
Strong nuclear force
Weak nuclear force
Electromagnetic force
Gravitational force
(SF)
(WF)
(EMF)
(GF)
1
10-6
1/137
6 x 10-39
Electromagnetic force - electrical charges, magnetism
If EMF were slightly weaker, electrons wouldn’t be held in their orbits
If EMF were slightly stronger, electrons couldn’t be shared among different
atoms
Either way, no chemistry and no life!
The four fundamental forces
rel. strength
Strong nuclear force
Weak nuclear force
Electromagnetic force
Gravitational force
(SF)
(WF)
(EMF)
(GF)
1
10-6
1/137
6 x 10-39
EMF/GF = 1036
If:
EMF/GF = 1030 no heavy elements, life impossible
Walter Bradley, Creation of the Cosmos
The four fundamental forces
rel. strength
Strong nuclear force
Weak nuclear force
Electromagnetic force
Gravitational force
(SF)
(WF)
(EMF)
(GF)
1
10-6
1/137
6 x 10-39
EMF/GF = 1036
If:
EMF/GF = 1030 no heavy elements, life impossible
Walter Bradley, Creation of the Cosmos
The four fundamental forces
Strong nuclear force
Weak nuclear force
Electromagnetic force
Gravitational force
(SF)
(WF)
(EMF)
(GF)
"The bulk of the carbon in our universe is produced in the triple-alpha
process in helium-burning red giant stars. We calculated the change of the
triple-alpha reaction rate in a microscopic12-nucleon model of the 12C
nucleus and looked for the effects of minimal variations of the strengths of
the underlying interactions. ... We conclude that a change of more than
0.5% in the strength of the strong interaction or more than 4% change in
the strength of the Coulomb force would destroy either nearly all C or all
O in every star.
H. Oberhummer, A. Csoto, H. Schlattl, Science 289, 2000, pg 88.
The anthropic coincidences
It is true, for example, that the fine structure constant a has to be close
to 1/137 for carbon atoms to exist, and carbon atoms are required for
us to be here writing about cosmology. However, these arguments
have nothing to do with explaining what physical laws led to this
particular value of a. …
The anthropic principle is an observation, not an explanation. To
believe otherwise is to believe that our emergence at a late date in the
universe is what forced the constants to be set as they are at the
beginning. If you believe that, you are a creationist. …
[Regarding a recent theory by S. Hawking and T. Hertog on this topic]
…it sounds to me a lot like the despised fine-tuning.
B. Richter, Physics Today, Oct 2006 p 8-9.
Following the discovery of this:
"A common sense interpretation of the facts suggests that a
superintellect has monkeyed with physics, as well as with
chemistry and biology, and that there are no blind forces worth
speaking about in nature. The numbers one calculates from the
facts seem to me so overwhelming as to put this conclusion
almost beyond question."
Fred Hoyle, "The Universe: Past and Present Reflections",
Annual Reviews of Astronomy and Astrophysics, 20 (1982), 16.
Another coincidence??
Colossians 1
15He
is the image of the invisible God, the firstborn over all
creation. 16For by him all things were created: things in
heaven and on earth, visible and invisible, whether thrones
or powers or rulers or authorities; all things were created by
him and for him. 17He is before all things, and in him all
things hold together.
Colossians 1:17
Part IV
fine tuning of the expanding universe
Some important observations
1. a). Light and other forms of radiation are detected that originated from
sources which are now very large distances (billions of light-years) away
Some important observations
2. Red shifts - the wavelengths of radiation from each galaxy are shifted toward the
red side of the spectrum by a factor roughly proportional to the distance of the
galaxy from us.
The universe
is expanding
Some important observations
-light gets stretched en route
-galaxies recede faster at greater distances
from “Creation as
Science”
H. Ross, p 92
Some important observations
3. Cosmic microwave background (CMB) radiation, nearly uniform in all
directions. This radiation does not come from a single source, rather it comes from
every point in the universe. Believed to represent radiation with a red-shift of
1,100. It is the earliest phenomenon that we will ever observe.
The universe
expanded
from a very
hot, dense
state
Implication
there was a beginning (creation event)
“Philosophically, the notion of a beginning of the present order of nature is
repugnant to me”
Arthur Eddington Nature 450, 127, (1931)
“I would like to reject it”
Phillip Morrison, God and the Astronomers, 1992, p 104
“Distasteful to the scientific mind”
Robert Jastrow, God and the Astronomers, 1992, p 105
Energy driving expansion precisely matched
to gravitational attraction
from “Creation as
Science”
H. Ross, p 96
expansion
too fast -
expansion
too slow -
expansion
just right -
all dust,
no stars
all black
holes
galaxies,
stars,
planets
One model:
mass density tuned to 1 part in 1060
Inflationary model:
energy density tuned to 1 part in 10120
Expansion of the universe - the most
remarkable example of fine-tuning
Job 9:8
Psalm 104:2
Isaiah 40:22, 42:5, 44:24, 45:12, 48:13, 51:13
Jeremiah 10:12, 51:15
Zechariah 12:1
“He alone stretches out the heavens …” Job 9:8
“He stretches out the heavens like a canopy…” Is. 40:22
Fine-tuning of the mass density
Also:
If too large, nuclear fusion too productive
no elements lighter than iron
If too small, nuclear fusion not productive enough
only hydrogen and helium
Fine-tuning of the mass density
Fine-tuning of the mass density
Suggests that
all the stars in
the universe
are required
for us to be
here today!
Fine-tuning of the mass density
“It is ironic that those very features of the cosmos that were so
troubling to the astronomers of the early seventeenth century - its
vast size and the apparently infinite number of stars stretched out
across its immensity …which seemed to render the earth an
irrelevant mote of dust in the cosmic scheme, have turned out to
be absolutely critical and essential for our existence.”
Michael Denton, Nature’s Destiny, p 14-15.
mass density, energy density of empty space
In any case, there is one constant whose value does seem remarkably well
adjusted in our favor. It is the energy density of empty space, also known
as the cosmological constant."
S. Weinberg, Skeptical Inquirer, Sept./Oct. 2001, pg 67.
At the Nature of Nature conference at Baylor University, April 2000,
Weinberg stated that the cosmological constant appears to be fine-tuned to
1 part in 10120.
mass density, energy density of empty space
Which fundamental fine-tuning problem is one more willing to worry about,
the flatness problem or the cosmological constant problem? The latter
involves a fine-tuning of over 120 orders of magnitude, if the cosmological
constant is nonzero and comparable to the density of clustered matter today,
while the former involves a fine-tuning of perhaps only 60 orders of
magnitude, if one arbitrarily fixes the energy density of the universe at the
Planck time to be slightly less than the closure density.
L. M. Krauss, The Astrophysical Journal, 1998, 501: p 465.
Naturalistic Response
“any cosmological theory that does not lead to the eternal reproduction of
universes will be considered as unimaginable as a species of bacteria that
cannot reproduce”
Alan Guth Discover 2002 pg 38.
Naturalistic Response
Infinite number of universes (last resort to salvage naturalism)
idea: if there is an infinite number of universes, and all
possible conditions happen, then some universe will be
“just right”
problems:
-fundamentally undetectable (causally disconnected)
-where did the other universes come from?
-no explanation for laws of physics
-why should all possibilities for constants occur?
-everything can (and does) happen, so explains nothing
Response to the Naturalistic Response
"Extreme multiverse explanations are . . . reminiscent of theological
discussions. Indeed, invoking an infinity of unseen universes to explain the
unusual features of the one we do see is just as ad hoc as invoking an unseen
Creator. The multiverse theory may be dressed up in scientific language, but in
essence it requires the same leap of faith."
Paul Davies, Op-Ed in the New York Times, "A Brief History of the
Mulitverse", Apr. 12, 2003.
Accepting the extremely improbable to
avoid an undesirable answer
Quotes from world-renowned scientists
"Here is the cosmological proof of the existence of God - the
design argument of Paley-updated and refurbished. The fine
tuning of the universe provides prima facie evidence of deistic
design. Take your choice: blind chance that requires multitudes of
universes, or design that requires only one. ... Many scientists,
when they admit their views, incline toward the teleological or
design argument."
E. Harrison, Masks of the Universe, 1985, 252, 263.
Quotes from world-renowned scientists
"Astronomy leads us to an unique event, a universe which was
created out of nothing and delicately balanced to provide
exactly the conditions required to support life. In the absence
of an absurdly-improbable accident, the observations of modern
science seem to suggest an underlying, one might say,
supernatural plan."
Arno Penzias, quoted by Walter Bradley in "The Designed 'Justso' Universe", 1999.
Quotes from world-renowned scientists
"The more I examine the universe and the details of its
architecture, the more evidence I find that the universe in some
sense must have known we were coming."
Freeman Dyson (Princeton Physicist), Disturbing the Universe,
1979, pg 250.
.
Quotes from world-renowned scientists
"If the Universe had not been made with the most exacting
precision we could never have come into existence. It is my view
that these circumstances indicate that the Universe was created for
man to live in."
John O'Keefe (NASA astronomer), quoted in R. Jastrow in God
and the Astronomers,1992, 118.
Quotes from world-renowned scientists
"As we survey all the evidence, the thought insistently arises that
some supernatural agency -or rather Agency- must be
involved. Is it possible that suddenly, without intending to, we
have stumbled upon scientific proof of the existence of a Supreme
Being? Was it God who so providentially crafted the cosmos for
our benefit?"
G. Greenstein, Symbiotic Universe: Life and Mind in the Cosmos,
1988, 27.
Quotes from world-renowned scientists
"... is for me evidence that there is something going on behind it
all. The impression of design is overwhelming."
P. Davies, Cosmic Blueprint: New Discoveries in Nature’s Creative
Ability to order the Universe, 1988, 203
Quotes from world-renowned scientists
"We can't understand the universe in any clear way
without the supernatural"
Allan Sandage, Astronomer, Interview with Fred
Hereen, quoted in Show Me God, pg 224
Quotes from world-renowned scientists
"For the scientist who has lived by his faith in the power of reason,
the story ends like a bad dream. He has scaled the mountains of
ignorance; he is about to conquer the highest peak; as he pulls
himself over the final rock, he is greeted by a band of theologians
who have been sitting there for centuries."
R. Jastrow, God and the Astronomers,1992, pg 107.
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