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Before the age cable TV, streaming video and
video games, there wasn’t much to do at
night except maybe gaze at the stars and look
at the beauty of the universe.
Until 350 years ago, there was a distinct
demarcation between what people observed on
earth and what people saw up in the sky. There
did not seem to be any connection. Things
that happened on earth could at least be seen
and explained at least in terms of cause and
effect.
The heavens seemed to be an utter mystery.
The motions planets, though predictable, did
not appear to follow the same patterns as
objects here on earth. To many this was the
sign of the hand of a creator. It must be
God that ruled over the universe, controlling
the movement of these heavenly bodies, and
to gaze at the stars was to bear witness to
the majesty of God’s design.
Along came Isaac Newton in 1687 with the publication
of the astounding Principia Mathematica, who
showed that heavenly bodies move due to the
same forces we experience here on earth.
Newton not only gave us a theory, but also
the mathematical basis that allowed us to
make very accurate predictions about not only
the motions of planets, but also the movement
and behavior of things right here on earth.
It was a total game changer.
If things could be explained with rational
laws and mathematics, to many people this
called into question the need for a God.
Arguments for the existence of God began to
fall out of favor. But in the late 20th century,
these arguments were resurrected. The standard
model of particle physics and general relativity
is spectacularly accurate. But there are constants
in these equations that do not have an explanation.
They have to be measured, and appear to be
just properties of the universe.
And it so happens that many of these constants are finely tuned. That is to say, if you change
them slightly in either direction, positively
or negatively, it could lead to a completely
different universe with no life at all.
Does this fine tuning finally give us the
answer to the question of God? Can it be shown
that God must be present within the constants
of physics? The answer is coming up right
now….
Ironically, Newton himself did not view his
equations as negating the need for God. To
him, the nature of gravity which he described
as action at a distance, meaning a force that
acts on things without touching it, was evidence
that God still had a hand in the universe.
But Newton wasn’t aware of, particle physics,
quantum mechanics and general relativity.
These are the best theories we have today
to explain the true workings of the universe.
And these theories require at least 19 constants, and they have to be measured.
So what accounts for these constants? There
are currently no equations or theories from
which these parameters arise.
And many scientists point out that some of
these are so finely tuned that even a slight
variation would have resulted in a universe
devoid of life. They point out for example,
the mass of a neutrino is 2X10^-37kg. It has
been shown that if this mass was off by just
one decimal point, that is if it was 2X10^-36kg
or 2X10^-38 kg, life would not exist because
if the mass was too high, the additional gravity
would cause the universe to collapse. If the
mass was too low, galaxies could not form
because the universe would have expanded too
fast. In either case life could not exist.
How lucky are we that there are exactly 36
zeros in this mass? Advocates of fine tuning
argument say that it can not just be a matter
of luck. The best explanation they say is
that the universe had a designer who fine
tuned it for life.
This is a very impressive argument indeed.
But on closer examination, it has some problems.
First, the argument exaggerates the idea of
fine tuning by using misleading units of measurement,
to make fine tuning seem much more unlikely
than it may be.
You’ll see for example, that the mass of
neutrinos is expressed in Kg. These things
are so small that any fluctuation expressed
in Kilograms would be a huge fluctuation.
Using kilograms to measure something this
small is the equivalent of measuring a person’s
height in light years.
It’s like saying that Lebron James is 2X10^-16
light years in height. If he was just 2X10^-15
or 2X10^-17 light years in height, he wouldn’t
have been able to play basketball. Well, this
is true, because it would mean 6 foot 9inches,
like he is, he would be either a 60 foot lumbering
giant or less than 8 inches tall. Lebron is
81 inches tall. The fact is that he was 4
inches shorter or taller, a difference of
5%, he would still be able to play basketball,
and he would probably still be one of the
best. So his height expressed in inches instead
of light years is a better way to look at
fine tuning.
So when you look at the constants expressed
in terms that make more sense, then the fine
tuning argument doesn’t seem all that impressive.
The kilogram measurement for the neutrino
is arbitrary, a better measurement would be
electronvolts or even picograms.
Another point is that although Lebron could
be any height – 1 foot, 1 inch, 10 feet,
100 feet. In reality, he is not going to be
1 foot tall. The average male in the U.S.
is about 5 feet 9 inches tall, so most males
are going to be close to that figure give
or take a foot, not give or take 5 feet. There
is no real chance that Lebron would be
60 feet tall.
Similarly, most of the constants of the universe
could not really be any arbitrary number,
they are going to hover around some value
close to what they actually are. The value
of the mass of a neutrino for example could
not be the mass of a bowling ball. Such massive
particles with the property of a neutrino
could not have been created during the Big
Bang.
So the person presenting the fine tuning argument
has to show that the values really need to
be in a very specific range using units of
measurement that are appropriate. And when
you put the argument in these terms, the argument is not so impressive.
The fine tuning argument also concludes that
the universe must be fine tuned based on the
observation that if one of its properties
were any different, life could not exist.
It has to have exactly the properties that
it has.
The problem with this statement is that it
presumes a narrow definition of life based
on the anthropic view that life has to be
the of the kind that we see on earth, in a
universe that has the properties of our universe.
Even if it were true that a universe with
different constants could not support life
as we know it, it does not follow that the
laws we have are the only ones conducive to
life.
For example, if the strength of electromagnetism
was slightly larger or smaller, it would mean
that atoms would be slightly smaller or larger,
respectively. This probably would not preclude
atoms form being formed, or chemistry from
taking place. Life could probably still exist,
but it would just be different.
If you have a square
with sides that are 1 meter in length. And
then you say, ok, if any of the sides were
anything other than 1 meter, for example if
the right side was 0.9 meters, then you would
no longer have a square. That is absolutely
correct.
But this does not mean that you could not
make a square with different length sides.
You could have a square with sides that are
50 centimeters, or 1 centimeter or 2 meters.
Just because one of the sides is a different
length for your square does not mean that
a different square has to have the same length
sides. There is more than one way to make
a square.
Similarly, there could be other universes
that support life with a different set of
constants.
Most scientists believe that in order to have
life in any universe, complex chemistry is
necessary because life needs complex bio chemicals to function. In order to have this kind of chemistry, larger
atoms such as carbon, oxygen, nitrogen and
iron are required.
But after the big bang, only the lightest elements,
hydrogen, deuterium, helium and lithium were
formed. The heavier elements were not produced
until hundreds of millions or billions of
years later. This time was needed in order
for large stars to form and assemble these
elements in their core, because that’s the
only place where fusion can form the larger,
heavier atoms of the periodic table. When
these large stars exploded, they spewed all
these atoms needed for life into space. Newer
stars like our sun formed, and planets also
formed around it containing these life-giving
elements.
In a 1983 paper, Press and Lightman showed
that much of the gross properties of the universe,
from the dimensions of atoms to the order
of magnitude of the lengths of the day and
year, can be estimated from the values of
just four fundamental constants. These are
the strengths of the electromagnetic and strong
nuclear interactions, and the masses of the
electron and proton.
Taking this information, Physicist Victor
Stenger did a study in 2000 where he varied
these 4 constants to see what the potential
universes would look like. He analyzed 100
universes in which he randomly varied the
constants by 5 order of magnitude above, and
5 order of magnitude below their actual values
in our universe. What he found was that over
half the universes would have stars that live
at least a billion years. This would be enough
time for large atoms and complex chemistry
to occur.
Although a long stellar lifetime is not the
only requirement for life, his study showed
that this very important parameter for life
is not an unusual property for a rather random
universe to have.
He also found some other interesting information.
For example, he found that if the mass of
the electron was 100,000 times lower, the
proton mass could be as much as 1,000 times
lower to achieve the same minimum stellar
lifetime. There are lots of combinations where
you could vary two or more constant and still
have viable universes.
There is more than one way to skin a cat,
and there is more than one way to build a
universe.
Another theory says that the constants we
happen to have is due to the probability inherent
in the laws of quantum mechanics. At the big
bang, cosmologists believe that the laws of
quantum mechanics became applicable. If this
is true then the wave equation of the universe
decohered or collapsed randomly in such a
way that the constants were set from the very
beginning.
There may have been multiple instances or
bubbles of universes. And each of these may
have had different initial conditions leading
to different sets of constants. Perhaps most
failed to develop.
Philosophers like John Leslie, of the University
of Guelph think that if the universe had multiple
tries before we happen to exist. And what
we see could be a form of natural selection
similar to evolution. If enough people buy enough lottery tickets, someone is going to win eventually.
If enough universes form, you’re bound to
get one with life like ours.
This is just one of several multiverse ideas
suggested by modern cosmological models, including
ideas that emerge from string theory, as well
as the many worlds interpretation of quantum
mechanics. No known principle rules out the
existence of multiple universes.
In fact, we would need to hypothesize a new
principle in physics to rule out all but a
single universe. If multiple universes exist,
then we are simply in that particular universe
of all the logically consistent possibilities
that had the properties needed to produce
us. Many scientists believe that
Science may someday have a theory from which the values of the existing physical constants
can be derived or explained. What looks like
fine tuning may really be due to our ignorance
of the underlying mathematics that would explain
these constants. Nature may ultimately reduce
to a single principle from which all these
constants could arise. But we are not there yet.
The fine-tuning argument seems to be saying
something analogous to the idea that the Sun
radiates light so that we can see where we
are going. In fact, the human eye evolved
to be sensitive to light from the sun because that's what gave us an evolutionary advantage. The
sun is not fine tuned for our eyes. Our eyes
are fine tuned for the sun. Similarly, the
universe is not fine-tuned for humanity. Humanity
is fine-tuned to the universe.
I want to point out that I don’t think many
scientists dispute that life as we know it
probably would not exist if the constants
of physics were different. And no one can
say for sure that some other form of life
is feasible with a different set of constants.
But anyone who insists that our form of life
is the only conceivable life, would be making
a claim based on no evidence and no theory.
You could argue that if God is not in the
constants, then he must be in the laws that
underlie the constants – the laws of quantum
mechanics and general relativity. After all,
if the universe follows fundamental laws,
there must be a law giver.
But the problem with this argument is that
you are replacing something like the laws
of physics that may be eternal, with something
else that is eternal but more complicated.
God is more complicated because he is infinitely
complex, and does not have to obey the laws
of physics.
Does it make more sense to say the universe
came into being because of a set of preexisting
laws, or the universe came into being because
a preexisting entity created eternal laws
which allowed the universe to come into existence.
According to professor David Johnson of Kings
College. It will be trying to explain the
currently unexplained, with something that
is inexplicable.
God may or may not exist. I don’t claim
to know the answer. He may be found at some
point, And some principle or theory of nature
may prove it. But he probably would not emerge
from the constants of the universe.
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