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__________________________________
HELP FILE FOR REQUIREMENT 1
INFORMATION ON REQUIREMENT 1
This screen and the next screen will discuss Requirement 1, one of 7
requirements for a biologically favorable universe.
When two protons collide in the core of the sun, sometimes at the moment
of collision the proton changes into a neutron, and the product of the
collision is a deuteron (a particle consisting of a proton and a neutron bound
together). This quick changing of a proton into a neutron is possible only
because the neutron is only about 1 part in 1000 more massive than the proton.
One particle can rarely or never change instantly into a second particle if
the second particle has much more mass than the first. So if a neutron
weighed significantly more than a proton, never or virtually never would a
proton change into a neutron. If the neutron mass were much greater than the
proton mass, the collision of two protons in the sun's core would never or
virtually never produce a deuteron. As a result, deuterons would almost never
form in the core of stars like the sun. (Since the average lifetime of a neu-
tron outside a nucleus is only about 15 minutes, there are few free neutrons
in the sun's core; so within stars deuterons rarely form from a collision of a
proton and a neutron.)
The formation of a deuteron is a crucial first step in the process by
which the sun produces nuclear energy. In our sun a vast number of deuterons
form every second. Scientists suspect that if deuterons rarely or never formed
in the cores of stars like the sun, no star in our galaxy would produce enough
energy to support the evolution of intelligent life on a planet revolving
it. So it seems that if the neutron mass were more than a few percent greater
than the proton mass, the universe would not be biologically favorable. There
is also a reason why the universe would not be biologically favorable if the
mass of the proton was significantly greater than the mass of the neutron.
A free neutron or a free proton is a proton or neutron that is not part of
a nucleus that consists of more than one proton or neutron. The lifetime of
a free neutron is only about 15 minutes. Whenever it is outside of a nucleus,
a neutron will quickly decay into a proton and an electron. Since they know
that any free neutron will quickly decay into a proton and an electron,
scientists think that if neutrons were less massive than protons it is the free
proton that would decay. According to the physicist Paul Davies, if the neutron
mass were .998 of its actual value, free protons would decay into neutrons, and
there probably would be no atoms at all.
The nucleus of a hydrogen atom is nothing but a free proton. So if free
protons decayed into neutrons (as they would if neutrons were very slightly
less massive), hydrogen would not exist. According to the physicist Heinz R.
Pagels, a mass change of less than 1 percent would make protons heavier than
neutrons, and would cause hydrogen to be nonexistent because of the decay
of protons into neutrons. An equivalent statement has been made by the
astronomer Fred Hoyle. Intelligent life could not exist in a universe
without hydrogen (which is one of the components of water).
So a universe cannot be biologically favorable unless its protons and
neutrons have almost exactly the same mass. In this program this requirement
is referred to as Requirement 1.
END OF HELP FILE FOR REQUIREMENT 1
HELP FILE FOR REQUIREMENT 2
INFORMATION ON REQUIREMENT 2
This screen and the next screen will give information on Requirement
2, one of the requirements for a biologically favorable universe.
Test have proven that the proton charge and the electron charge differ by
less than 1 part in 1,000,000,000,000,000. We know that the proton charge and
the electron charge differ by less than .00000000000000000000000000000001
coulomb.
An object is electrically neutral if the amount of positive charge in
it is precisely equal to the amount of negative charge in it. Because
the charge of the electron has the same magnitude as the charge of
the proton, atoms tend to be electrically neutral. In other words, in
a typical atom the total amount of negative charge is equal to the
total amount of positive charge. But if the proton charge did not have the
same magnitude as the electron charge, atoms would not be electrically
neutral. In such a case almost all atoms would have either a net positive
charge or a net negative charge. If the proton charge were larger than
the electron charge, almost all atoms would have a net positive charge. If
the electron charge were larger than the proton charge, almost all atoms
would have a net negative charge.
It is a fundamental law of nature that any two particles with
like charges repel each other. If the proton charge did not
have the same magnitude as the electron charge, there would be a
force of repulsion between almost all atoms.
According to the scientist George Greenstein, if the proton
charge differed from the electron charge by only one part in a billion,
there would be a force of repulsion between atoms that would cause
all small objects such as stones or bodies to burst apart. According
to Greenstein, if there was a difference of even 1 part in a quintillion
(1 part in 1,000,000,000,000,000,000) between the proton charge and
the electron charge, very large bodies such as the earth could not
hold together; the repelling force between atoms would cause such
bodies to burst apart.
By using the elementary scientific law called Coulomb's law, anyone
can quickly calculate the force of repulsion that would exist on a planet-
sized body if there was a difference of even
.0000000000000000000000000000000001 coulomb between the charge of the
electron and the charge of the proton. Calculations with this law
show that if such a difference existed (a difference of less than 1
quadrillionth of an electron's charge), there would be an incredibly
vast force of repulsion acting on any body the size of the earth. Such a
force would prevent the stable existence of any body as large as
a planet.
Consequently, it seems that a universe cannot be biologically favorable
unless within that universe the magnitude of the proton charge is
equal to the magnitude of the electron charge. This requirement is
referred to in this program as Requirement 2.
END OF HELP FILE FOR REQUIREMENT 2
HELP FILE FOR REQUIREMENT 3
INFORMATION ON REQUIREMENT 3
This screen and the next two screens will discuss Requirement 3, one
of the requirements for a biologically favorable universe.
During the first few minutes after the expansion of the universe
began, roughly 25 percent of the universe's hydrogen was converted
into helium. All of the universe's hydrogen would have been
converted to helium if the strong nuclear force were strong enough
to cause two protons to form a single helium nucleus lacking a
neutron (such a nucleus is called a diproton). But the strong nuclear
force is not quite strong enough to do this. The strong nuclear force
has only about 97 percent of the strength it would need to form
diprotons. Many scientists (such as B. J. Carr and M. J. Rees) have
said that if the strong nuclear force had been a few percent stronger
during the universe's early history, essentially all of the universe's
hydrogen would have been converted into helium shortly after the Big
Bang.
If hydrogen did not exist, there would be no water, since
water is composed of hydrogen and oxygen. Scientists generally think
that life could not exist without water. If hydrogen did not exist,
there would not be any long-lived, brightly burning stars like the
sun. There would only be relatively short-lived stars made of helium.
Suppose that the strong force were more than 5 percent stronger,
and that a large amount of hydrogen had somehow survived from the
time of the early universe. According to Freeman Dyson and other
scientists, if the strong nuclear force were more than a few percent
stronger, particles called diprotons would form in the sun's core, and
consequently thermonuclear reactions in the sun would be something
like a million trillion times more efficient. Dyson and other scientists
say that if diprotons tended to form in the cores of stars, all stars
would use up their thermonuclear fuel in a relatively short time, and
no star would shine brightly for a period long enough to allow the
evolution of intelligent life on any planet. According to the astrono-
mer Nigel Henbest, if the strong nuclear force were more than 3
percent stronger, stars would spontaneously explode as soon as they
formed.
Suppose, on the other hand, that the strong nuclear force had
always had a strength less than a hundredth of its actual strength.
Protons all have a positive electric charge, and there is an electrical
repelling force between any two nearby particles with a positive
charge. The strong nuclear force keeps protons bound together
in the core of the nucleus. But
if the strong nuclear force had a strength less than a hundredth
of its actual strength, protons would not stay bound together in the
cores of atoms, and there would be no atoms with more than one
proton in the nucleus. In such a case there would be no element
other than hydrogen.
What if the strong nuclear force were only a third as strong as it
actually is? In such a case there might exist a few elements heavier
than hydrogen, but almost all elements would be unstable. Carbon
and oxygen, if they existed, would not be stable elements. They would
be unstable elements with relatively short lifetimes. Planets, if any
existed, would be continually bathed by an intense radioactivity caused
by the radioactive decay of unstable elements.
Actually, intelligent life probably would not exist in our galaxy if
the strong nuclear force had always been more than a few percent
weaker. The physicist Paul Davies has said that if the strong force
were about 5 percent weaker, the deuteron could not exist. A
deuteron is a nucleus consisting of a proton and a neutron bound
together by the strong force. Deuterons play a crucial role in the
processes that produce energy for the sun.
A star like the sun gets most of its energy from a series of
thermonuclear reactions that begins with the formation of a deuteron.
If the deuteron could not exist, stars probably would not be able to
produce large amounts of energy through thermonuclear reactions.
If the deuteron could not exist, there probably would not have been
any star that shined brightly for long enough to allow the evolution
of intelligent life anywhere in our galaxy.
So it seems that a universe can only be biologically favorable if it
has a strong force that is neither much stronger nor much weaker
than the strong force in our universe. This requirement is referred to
in this program as Requirement 3.
END OF HELP FILE FOR REQUIREMENT 3
HELP FILE FOR REQUIREMENT 4
INFORMATION ON REQUIREMENT 4
This screen and the next screen will discuss Requirement 4, one
of the requirements for a biologically favorable universe.
For purposes of convenience, the term `the epsilon constant' can be
used to mean the fine structure constant to the twelfth power multiplied
by the electron/proton mass ratio to the fourth power. In our universe
the epsilon constant has a value of 2.0e-39, and an important parameter
called the gravitational fine structure constant has a value of 5.9e-39.
For reasons that are too technical to be explained here, scientists say
that if the gravitational fine structure constant was much larger or much
smaller than the epsilon constant, all stars would be either blue giant
stars or red dwarf stars.
In an article in the journal Nature, the scientists B.J. Carr and M.J.
Rees said that if the gravitational fine structure constant were "slightly
larger, all stars would be blue giants; if it were slightly smaller, all
stars would be red dwarfs."
Clearly a universe would not be biologically favorable if it had only
red dwarf stars or only blue giant stars. Blue giant stars only have a
lifetime of less than 150 million years. It took more than three billion
years for earthly life to evolve from the simplest stage to the stage of
advanced mammals. So if all stars were blue giants, there would not
be sufficient time for life to evolve on any planet. The highest forms
of life can only evolve on a planet if that planet revolves around a star
with a lifetime at least several times longer than the maximum
lifetime of a blue giant star.
Red dwarf stars have very long lifetimes. But these stars shine
dimly, with a luminosity that is only a tiny fraction of the sun's
luminosity. A planet could only get sufficient heat from a red dwarf
star if the planet was very close to the star. According to scientists
such as Isaac Asimov, any planet that close to a red dwarf star would
be subjected to tremendous gravitational forces coming from the star.
These forces (called tidal forces) would prevent the planet from
rotating. As a result, one side of the planet would be far too hot, and
the other side would be far too cold. The resulting· drastic differen-
ces in temperature would cause the planet to lose its atmosphere.
As George Gale puts it in Scientific American, "Neither a blue
giant nor a red dwarf can support life; the blue giant dies too soon,
and the red dwarf radiates too weakly."
So it is right to say that a universe can only be biologically
favorable if it has a gravitational fine structure constant that is not
many times larger or smaller than the epsilon constant. In this program
this requirement is referred to as Requirement 4.
END OF HELP FILE FOR REQUIREMENT 4
HELP FILE FOR REQUIREMENT 5
INFORMATION ON REQUIREMENT 5
This screen and the next screen will discuss Requirement 5, one
of 5 requirements for a biologically favorable universe.
The primordial expansion velocity is the speed at which the universe
expanded at the time of the Big Bang, when the universe began to
expand from an incredibly small volume. The primordial escape
velocity is the minimum speed at which the universe had to expand
in order to escape the inward pull of the universe's gravity, which
resisted the universe's expansion.
Scientists say that the primordial expansion velocity was precisely
equal to the primordial escape velocity. In other words, at the time
of the Big Bang the universe began to expand at just the minimum
rate necessary for the universe to overcome its gravity, and keep
expanding indefinitely.
Scientists say that if the primordial expansion velocity had been
even 1 part in a million greater than the primordial escape velocity,
the universe would have expanded so rapidly that no galaxies would
have formed in it. In such a case there would have been no stars like
the sun, and the universe would have been lifeless. Scientists say that
if the primordial expansion velocity had been even 1 part in a million
smaller than the primordial escape velocity, the universe's matter
would have formed into black holes rather than galaxies. In such a
case there would have been no stars like the sun, and the universe
would have been lifeless.
So it right to conclude that a universe will not be biologically
favorable without an equality between the primordial expansion velocity
and the primordial escape velocity. This requirement is referred to in
this program as Requirement 5.
END OF HELP FILE FOR REQUIREMENT 5
HELP FILE FOR REQUIREMENT 6
INFORMATION ON REQUIREMENT 6
This screen and the next screen will give information on Require-
ment 6, one of the requirements for a biologically favorable universe.
The universe is expanding. Its expansion is inhibited by the inward
force of gravity generated by the galaxies, just as the rise of a rocket
toward space is inhibited by the gravity of the earth. Gravity inhibits
the expansion of the universe, and the force of gravity decreases as
the distance grows between astronomical bodies. But imagine a
cosmic force with the opposite characteristics: a force that increases
with distance, and causes the universe to expand more rapidly.
Scientists call such a force the cosmological constant.
The value of the cosmological constant can be stated in terms such
as "less than .0000000000000000000000000000000001 per square meter."
Physicists are puzzled by why the cosmological constant
does not have a value more than 1,000,000,000,000,000,000,000,000
times larger than the value it has in our universe.
What would the effect be if our universe had a significant
cosmological constant? According to Larry Abbot's article in
Scientific American, if the cosmological constant had a value of
.0001 per square meter, a distortion of spacetime would occur over any
distance of more than a few kilometers. As a result, if anyone traveled
more than a few kilometers, he would not even be able to return
to his place of origin. Accordingly, we can safely assume that life
could not evolve in a solar system if the cosmological constant had a
value of more than .0000000001 per square meter. If the cosmological
constant had such a value, there would be a distortion of spacetime
over any distance of 10 billion meters, which is roughly a
tenth of the distance from the earth to the sun. Because of such a
distortion, planets would not even be able to have suitable orbits
around stars.
A cosmological constant can be negative or positive. A positive
cosmological constant would cause the universe to expand at a rate
much faster than our universe is expanding. A negative cosmological
constant would act as a force inhibiting or preventing the expansion
of the universe.
Scientists say that the universe would not have many stars if it had
originally expanded at a rate much different from its actual rate of
expansion. Scientists say that galaxies would not have formed if the
universe had expanded at a rate much faster than it did expand.
Conversely, scientists think that if the universe's expansion rate had
been slightly slower, the universe's matter would have formed into
black holes rather than galaxies.
So if the universe had a significant cosmological constant that was
positive, it would expand too fastly for galaxies to form in it. If the
universe had a significant cosmological constant that was negative, it
would expand too slowly for galaxies to form.
According to the scientist Paul Davies, if the universe had a
positive cosmological constant that was several powers of ten greater
than .00000000000000000000000000000000000000000000001 per square meter,
the expansion of the universe would be explosive,
and it is doubtful if galaxies ever could ever have formed. On the
other hand, if the cosmological constant were negative, the expansion
of the universe would be replaced by a catastrophic collapse of the
universe.
So it seems that a universe cannot be biologically favorable
unless it has a cosmological constant extremely close to zero. In this
program this requirement is called Requirement 6.
END OF HELP FILE FOR REQUIREMENT 6
HELP FILE FOR REQUIREMENT 7
INFORMATION ON REQUIREMENT 7
This screen and the next two screens will discuss Requirement 7,
one of the 7 requirements for a biologically favorable universe.
When the universe was about 100 seconds old, about 25 percent of
its hydrogen was converted into helium. According to a scientific
paper by B. J. Carr and M. J. Rees in the journal Nature, if the
weak nuclear force had been slightly smaller in the early universe, 100
percent of the universe's hydrogen would have been converted to
helium, and life probably could not exist. (Without hydrogen there
would be neither water nor proteins nor stars like the sun.)
Two types of thermonuclear reactions are vitally
important to the production of energy by the sun. First,
when two protons collide the product is often a deuteron (consisting
of a proton and a neutron bound together), a positron, and a
neutrino. Second, when a deuteron collides with a proton the product
is often a light helium nucleus and an emission of energy.
The second of these reactions can only occur if the first of these
reactions has occurred, and it is the weak nuclear force that enables
the first of these reactions to occur. When two protons collide, the
weak nuclear force changes one of the protons into a neutron. This
allows the deuteron to form. However, the weak nuclear force only
helps to produce a deuteron in a small fraction of the times when two
protons collide in the sun's core. Because the weak nuclear force is
only a tiny fraction as strong as the strong nuclear force, ther-
monuclear reactions in the sun's core occur at a favorable rate.
If the weak nuclear force were a relatively small number of times
weaker, energy-producing thermonuclear reactions would occur so
infrequently that stars like the sun would not exist. There would be
only dim stars that would not provide enough energy to support the
evolution of intelligent life on rotating planets revolving around them.
On the other hand, scientists know that stars use up the hydrogen in
their cores relatively quickly if their rate of energy production is vastly
higher than the sun's rate of energy production; such stars have
lifetimes of less than 100 million years. If the weak nuclear force were
a relatively small number of times stronger, thermonuclear reactions
would occur at such a high rate that all stars would use up their
thermonuclear fuel relatively quickly, and no star would shine brightly
for more than 100 million years. For intelligent life to evolve on a
planet, the planet must revolve around a star that shines brightly for
much longer than 100 million years. (It took more than three billion
years of biological evolution before intelligent life appeared on this
planet.) The physicist Freeman Dyson has said that any form of life
dependent on sunlike stars would "be in difficulties" if the weak
nuclear force were much stronger or much weaker.
The weak nuclear force also plays an important role in super-
nova explosions. A supernova explosion is what occurs when a dying
star blows up, shooting its matter into space in an awesome blast.
Although they may sound like undesirable phenomena, scientists
believe that life would not exist in the universe if there had been no
supernova explosions.
These explosions of stars are of crucial importance.
After the Big Bang, the universe had essentially no elements other
than hydrogen, helium, and lithium. All elements other than hydrogen
and helium are called heavy elements. All the important heavy
elements such as carbon and oxygen originated within stars, and now
exist outside of stars only because of supernova explosions. These
explosions of stars shoot the heavy elements into the large clouds of
gas and dust that drift between stars. Solar systems form from these
clouds of gas and dust. Astronomers believe that if supernova
explosions had never occurred, there would never have been any
planets like the earth or any living things. If there had been no
supernova explosions, all of the important heavy elements would exist
only inside of stars.
Scientists say that supernova_explosions are caused by
neutrinos emerging from the core of a dying star. Scientists say that
if the weak nuclear force were a relatively small number of times
weaker, when neutrinos shot out from the collapsing core of a dying
star the neutrinos would pass through the outer layers of the star
without blasting these layers into space. Scientists also say that if the
weak nuclear force were a relatively small number of times stronger,
these neutrinos would not reach the outer layers of the star in time
to stop the entire star from undergoing a gravitational collapse. In
either of these cases supernova explosions would not occur. The
astronomer Nigel Henbest has said that if the weak nuclear force
were ten times weaker or ten times stronger, supernova explosions
would not occur. Scientist say that if supernova explosions had
not occurred, all the heavy elements needed for life would exist only
inside stars.
So it seems a universe can only be biologically favorable if it has a
weak force that is neither too strong nor too weak. In this program
this requirement is referred to as Requirement 7.
END OF HELP FILE FOR REQUIREMENT 7