Tuesday, April 21, 2015

Video: Guillermo Gonzalez on the Fine-tuning of the Universe to Support Life


Guillermo Gonzalez, Grove City College, PA
On Guard, July 27-28, 2012


Other posts on this subject can found in the Cosmology section of my Articles and Links Arranged by Subject page. In particular, a list of fine-tuned parameters can be found at The Fine-Tuning of the Universe to one part in 10^10^123 is best explained by an intelligent designer and creator, aka. God.

Below are some of the slides from the lecture by Dr. Gonzalez. I have (with permission) included some of the commentary from the lecture with the slides and edited the text for clarity and readability. Any transcription errors or typographical errors are my own. Please see the video for the original content.

Contents

1:18


What is fine-tuning?
  • Over the past century, scientists have discovered that if certain properties of the universe were changed very slightly from what they are, life could not exist in the universe. These properties have to be within a very narrow range for our universe to be life-permitting (habitable). This sensitivity of the habitability of the universe to small changes in its properties is called fine-tuning.

  • This was recognized about 60 years ago by Fred Hoyle, who was not a religious person. Paul Davies, Martin Rees, Max Tegmark, Bernard Carr, Frank Tipler, John Barrow, and Stephen Hawking also believe in fine-tuning.
2:37
A fine-tuned universe

"The possibility of life as we know it depends on the values of a few basic physical constants and is, in some respects remarkably sensitive to their numerical values. Nature does exhibit remarkable coincidences."
- Martin Rees

"The present arrangement of matter indicates a very special choice of initial conditions."
- Paul Davies

"The remarkable fact is that the values of these numbers [i.e. the constants of physics] seem to have been very finely adjusted to make possible the development of life."
- Stephen Hawking

3:35
Three types of fine tuning
  1. Fine-tuning of the laws of nature.

    Existence and forms of physical laws (forces, types of particles, quantum principles, dimensionality of space-time).

    Examples:

    • FG= Gm1m2/r2

      The force of gravity is proportional to the product of two masses and inversely proportional to the square of their separation.

    • The Pauli Exclusion principle dictates how electrons are arranged in atoms and pretty much determines the whole structure of the periodic table and therefore all of chemistry.

    • The Heisenberg uncertainty principle.

  2. Fine-tuning of the constants of physics.

    Masses of fundamental particles, force strengths, cosmological constant value.

    Constants: In Gm1m2 (above), G is a constant. Other constants are:masses of fundamental particles, electron, proton, quarks, constants for electromagnetic force, strong force, weak force, cosmological constant.

  3. Fine-tuning of the initial conditions of the universe.

    Initial entropy, initial expansion rate, initial density fluctuations, inflation, matter/antimatter ratio.
Contents
10:10
Possible objection 1

Q: How can you assign a probability when the sample size is precisely one (universe)? You can't say, for example, that 1 in 100 universes are habitable.

A: Run a hypothetical universe creating machine with different settings for the fine-tuning parameters and place a black dot on a chart of the results if it makes a non-habitable universe. Place a white dot when it is habitable. You will get a white dot is in a sea of black dots.

12:12
Possible objection 2

Q: What about universes governed by different laws of nature that allow radically different forms of life than those in our universe? Maybe constants and initial conditions in those universes aren't fine-tuned.

A: The answer to the question is not relevant to explaining the fine-tuning of our universe.

13:59
Possible objection 3

Q: If the constants and initial conditions had been different, we wouldn't exist, but maybe other forms of life would have been possible given the same laws.

A: Several of the examples of fine-tuning would prevent even the precursors to life. No planets, no galaxies, no chemistry! Slight changes in some parameters would result in a universe that is all black holes, all hydrogen, or it would collapse back on itself immediately.

Contents
How do you define fine-tuning?

A 10 cm ruler with an accuracy of 1 mm would have a relative error of 1%. In analogy to fine-tuning, 1% corresponds to the amount of fine-tuning (one part in 102), and 10 cm is called the comparison range.

Similarly, for fine-tuning, you need to define a suitable comparison range. It could be theoretical or empirical. A physical property of the universe is usually considered fine-tuned if the life-permitting range is < 10% of the comparison range.
18:25
A sense of big numbers
  • There are about 1013 cells in the human body.

  • The number of seconds in the entire history of the universe = 1017

  • Number of subatomic particles in the known universe = 1080


  • Having a precision of one part in 1030 is like firing a bullet and hitting an amoeba at the edge of the observable universe.

  • Some examples of fine-tuning require greater precision than this!
20:05
One- and two-sided fine-tuning

  • Some cases of fine-tuning are one-sided, meaning that a parameter falls near the edge of the life-permitting region.

  • Some cases of fine-tuning are two-sided:
In one sided fine-tuning, there is either a minimum or a maximum value of the parameter beyond which the universe would be uninhabitable. In two sided fine-tuning there is both a minimum and a maximum value and if the parameter was outside this range, the universe would be uninhabitable.
Example: How a comparison range is calculated to determine the fine-tuning of the forces of nature:

21:24

G0=Strength of gravity

Strength of weak force: 1031G0

Strength of electromagnetism: 1037G0

Strength of strong nuclear force: 1040G0

The natural range of forces in the universe spans 40 orders of magnitude. Therefore 1040 is an empirical comparison range. It is a lower limit because theoretically it could be greater.

23:12
Examples of fine-tuning
  • Fr. Robert Spitzer notes that there are at least 20 independent constants and factors that are fine-tuned to a high degree of precision for life to be possible in the universe.

  • The number continues to increase at a rate near one per year.
Contents
24:16
One-sided example 1

The maximum value of the electromagnetic force that allows a periodic table of sufficient length is 14 x 1037G0. Its degree of fine-tuning is:

(14-1)x1037G0/1040G0 ~ 1%.

26:04
One-sided example 2

The maximum value of the gravitational force that allows stars to last at least 109 years = 3000G0. Its degree of fine-tuning is 3000G0/1040 ~ 1/1036.

But that is just one effect of gravity. When you consider other effects, the possible values are fewer. If gravity is stronger, a planet must be smaller so that complex life is not crushed, but then the planet will cool too fast if it is small. These multiple constraints put tighter limits on the strength of gravity.

27:37
Fine-tuning analogy

Radio dial stretched across the universe

WKLF ("K-Life"): You better tune your dial to the first Angstrom if you want to tune gravity for life!

28:35
One-sided example 3

If the weak force is decreased by a factor of 30, the initial neutron/proton ratio would be ~0.90, leading to nearly pure helium universe.

The degree of fine-tuning is ~ 1/109.

The weak force is also involved in supernova explosions which distribute heavy elements throughout the galaxy. Heavy elements are needed for rocky planets and biological organisms. The weak force also determined the relative numbers of protons and neutrons in the early universe which determined the amount of helium in the universe. The weak force also controls radioactive decay which is responsible for most of the heat in the earth's interior. All three effects of weak the force, geophysical heat, amount of helium in early universe, and supernovae limit the values of the weak force that would permit the universe to be habitable.
Contents
31:20 Carbon production


  • Life-essential 12C is formed inside stars via the nuclear reaction:

    3α ---> 12C

    (The symbol α represents an alpha particle, a helium nucleus containing two protons and two neutrons.)

  • In the early 1950s, physicists did not think this reaction could operate in stars. Fred Hoyle made a prediction. We're here, as carbon based intelligent life, so somehow 12C must get produced. What would enhance the rate was a then unknown excited state of 12C at 7.7 MeV above the ground state.

  • The state was discovered by subsequent experiment.
32:32
Carbon production is fine-tuned
  • The production of carbon via the 3α process is an example of fine-tuning.

  • Oberhummer et al. (2000, Science) studied the relative production of C and O in stars. They showed that a 0.5% change in the strong nuclear force or a 4% change in the electromagnetic force would lead to large changes in the C/O ratio in the universe (due to changes in the energy of the 12C resonance level).

  • But wait, there's more...
34:19
Carbon production is fine-tuned


  • A collision of two α particles
    produces
    8Be
    which has a short lifetime of
    10-16sec. This short lifetime prevents runaway fusion that would result in early stellar explosions (before life-essential heavy elements are formed). The instability of 8Be leads to stellar stability. But, its lifetime could not be much shorter, or the reaction to produce carbon could not proceed.

  • There is another fine-tuning with 16O, which lacks a resonance level near the typical α particle energy in a star. If such a resonance level existed, most of the carbon would be converted to oxygen.

  • Fourthly, a conservation law prevents most of the 16O from being converted to 20Ne (via α-capture), which has a resonance at the right energy.
Because of the fine-tuning, there are comparable amounts of carbon and oxygen in the universe instead of mostly carbon or mostly oxygen. Both are needed to support life. Oxygen is needed for water and energy metabolism for complex intelligent life.
Contents
36:50
The cosmological constant (dark energy)
"Our current understanding of gravity and quantum mechanics says that empty space should have about 120 orders of magnitude more energy than the amount we measure it to have. That is 1 with 120 zeroes after it! How to reduce the amount it has by such a huge magnitude, without making it precisely zero, is a complete mystery. Among physicists, this is considered the worst fine-tuning problem in physics."
- Lawrence Krauss, (Scientific American, Aug. 2004, pp. 83-84)
38:38
The initial entropy of the universe

  • The initial state of the space-time (and thus gravity fields) of the early universe were very smooth and homogeneous (very low entropy).

  • Present entropy of the universe is much greater than the initial entropy.

  • Initially low entropy is required for a habitable universe in which high-entropy structures like stars form out of the surrounding low entropy space-time.

  • Roger Penrose estimated that the amount of fine-tuning required of the initial entropy to allow for a habitable universe is 1 part in 1010123!

Contents
43:10
Multidimensional fine-tuning

  • To be precise, you cannot just change one parameter while holding all others constant. Changing another parameter might compensate for the life-inhibiting effects of a particular parameter change.

  • Example: reducing the weak force can be compensated by reducing the mass difference between the proton and neutron in the early universe.

  • However, it is usually the case that changing a parameter has multiple different effects. Reducing the weak force also affects the explosion of massive star supernovae and radioactive decay.
46:31
Local fine-tuning

  • Each instance of global fine-tuning must be evaluated by its effects on habitability at the "local" level. By local, we mean structures within the universe that are relevant to life. These include galaxies, stars, and planets.

  • Knowing the number and ranges of properties of galaxies, stars, and planets will allow us to determine if a change to a particular global parameter will have life-inhibiting effects.

  • This involves details of star and planet formation, climate stability, orbital dynamics, stellar nucleosynthesis, etc.

Contents
51:33
Some history
"[Evidence for God comes] from the order of the motion of the stars, and of all things under the dominion of the Mind which ordered the universe."
- Plato (Laws 12.966e)

"...when the night had darkened the lands and they should behold the whole sky spangled and adorned with stars; and when they should see ... the rising and settings of all these celestial bodies, ... when they should behold all these things, most certainly they would have judged ... that all these marvelous works are the handiworks of the gods."
- Aristotle (On Philosophy)

52:59

Reconstructing historical events

The universe is an artifact. How do you reconstruct a historical event?

Not all science is laboratory based. Some science is historical. Geology, archeology, cosmology, astronomy are all historical sciences. There is a type of reasoning that is appropriate to historical sciences called abductive reasoning or inference to the best explanation. It's the way causal explanations are reached in the historical sciences. Abductive reasoning infers unseen causes in the past from facts in the present. If you discover an artifact or a pattern, and you want to determine a causal explanation for it, you apply the principle of uniformitarianism: apply the same kinds of causal explanations we use in everyday life to infer the best explanation for past unobserved events. If an artifact or pattern could be the result of several causes, you set up competing hypotheses based on mutually exhaustive possible explanations and choose the best one. The list of mutually exhaustive possible explanations is: necessity, chance, or design.

If you can rule out chance and necessity you can conclude the cause is design.

A meaningful pattern is improbable and rules out chance.

If you can infer a purpose it gives stronger evidence of design.

59:55
Chance

The conditions that allow for a life-permitting universe are highly improbable.

1:00:24
Necessity

The properties of the universe we observe are not logically necessary. They could have been otherwise.

M-theory explains how you could have other universes with different properties.

(There is a distinction between physical necessity and logical necessity.)

1:01:28
A meaningful pattern

The correlation of the conditions that allow for life and the fine-tuned parameter values of the universe we observe forms a meaningful pattern.

1:01:50
Summary of design argument

We can make a design argument:

  1. The fine-tuning of the universe is due to logical necessity, chance or design.

  2. It is not due to logical necessity or chance.

  3. Therefore, it is due to design.

Contents
1:02:47
What is the Anthropic Principle?

  • The Anthropic Principle is the recognition that our very existence constrains the properties of the universe we observe to be those that allow our existence. We can only observe a habitable universe!

  • It is merely a reminder that we have to take into account observer self-selection bias in interpreting our observations. Our sample of universes is necessarily biased.

  • The Anthropic Principle does not explain why there exists a universe fine-tuned for life in the first place.
1:03:30
Why can't the Anthropic Principle explain us?

Illustration:

  • Quasars were discovered to be very distant in 1963 from their large redshifts.

  • Why are they so luminous?

  • Wong answer: because if they weren't, we wouldn't be able to see them. If we see an object in the distant universe, then it must be very luminous.

  • Right answer: Quasars are powered by the gravitational energy released by matter falling into a supermassive black hole.
The anthropic principle is stating a necessary condition to make the observation. It is not explaining the cause of the observed phenomenon.
Contents
1:05:04
What about the multiverse objection?

  • If there exists a vast multiverse, the probabilistic resources available to account for our finely tuned universe by chance are increased. Then, we could appeal to the Anthropic Principle.

  • Some cosmologists try to make the case that a multiverse actually exists.

  • Chaotic eternal inflation - popular universe generator. Assume for the sake of argument.

Contents
1:10:12
Problem 1: Why such a large universe?
"... do we really need the whole observable universe, in order that sentient life can come about? This seems unlikely ... Let us be generous and ask that a region of radius one tenth of the ... observable universe must resemble the universe that we know, but we do not care about what happens outside that radius ... we can estimate how much more frequently the Creator comes across the smaller than the larger regions. The figure is no better than 1010123. You see what an incredible extravagance it was (in terms of probability) for the Creator to bother to produce this extra distant part of the universe, that we don't actually need .. for our existence."
- Roger Penrose
If we live in a multiverse generated by a process like chaotic inflation, then for every observer who observes a universe of our size there are 1010123 who observe a universe that is just 10 times smaller. That means if the universe really did arise from chaotic inflation, from just a quantum fluctuation of a vacuum, then the universe that we see beyond our region of space, say the nearest few hundred million light years, is not really there its an illusion, if you take this to the extreme ...

Contents
[Shortly after 1:05:04]
Boltzmann Brains

"One argument that the universe had a beginning is that it hasn't reached thermal equilibrium or "heat death" yet. If the universe was infinite in age, it would have reached thermal equilibrium an infinity of time ago - so that is evidence of a beginning of time. Ludwig Boltzmann in the 19th century said the whole vast universe could be at thermal equilibrium except we only observe this tiny little patch. This patch is not in thermal equilibrium just by chance ... we have reached heat death but not in this tiny little patch. The bigger the patch is, the more improbable it is so the universe is much vaster than it needs to be to account for our existence. If you just have a solar system pop out of a statistical fluctuation its much more probable than to have this big vast universe pop out of a statistical fluctuation. Then if we see this big vast universe and just our solar system popped out of a statistical fluctuation, then it must be an illusion, The stars that we see are really not there, everything beyond the solar system is an illusion, you have to believe in illusionism so it was rejected."

1:11:31

"The Boltzmann argument is relevant to the multiverse argument today."

"Taken to the extreme we can have a universe pop out of a quantum fluctuation that contains one brain. Boltzmann's brains are by far the most common observers in the multiverse given their small size. The smaller the universe the more probable it is. Its far more probable for a Boltzmann's brain to occur in a multiverse than our vast fine-tuned universe with its long history. And so you're more likely to be a free floating brain than a person with a real history living in a 13.7 billion year old universe. The world we observe then is an illusion. You're the only person who actually exists. All your memories are false. The probability of forming our universe out of a quantum fluctuation at its present state with the appearance of age is more likely than forming it with its finely tuned initial conditions and its long history and so this is called the attack of the Boltzmann brains and its a real conundrum for the multiverse advocates. They basically have to give up realism and the whole world around them is an illusion if they want to believe in multiverse because the most common observer in the multiverse is a Boltzmann's brain."

[Q&A 1:27:00]

If the multiverse theory is true then the most probable reality is that there is no fine-tuning, the universe arose as a quantum fluctuation consisting only of your brain, and everything else is an illusion. To believe in the multiverse is to believe in illusionism.

Contents

1:12:50
Problem 2: The rejection of rationality

  • Anything that can happen, no matter how improbable, does happen countless many times in the multiverse.

  • Anything can be attributed just as readily to human design or to chance fluctuations of the quantum vacuum of the inflaton field.

  • Renders all scientific reasoning and explanations unreliable. Must believe in random miracles!

Multiverse cosmology can explain the origin of all events no matter how improbable, as long as they're not impossible, by reference to chance because of the infinite probabilistic resources it provides. Events we explain in terms of known causes based on ordinary experience are just as readily explained in multiverse cosmology as chance occurrences without any causal antecedent.

There is no way to attribute events to causal physical laws. All causes as seen to be related to effects really aren't. They're just chance fluctuations. Chance events. So you do away with the possibility of all scientific reasoning because scientific explanation and reasoning are unreliable. You must believe in random miracles. The scientific method is dead if you believe in the multiverse.


Contents
1:14:24
The best explanation

  • Design is the best explanation for the fine-tuning of the universe.

  • From our uniform and repeated experience, objects we know are designed are always associated with minds and never otherwise.

  • Multiverse cosmologies invoke causes we have no experience with and Anthropic explanations fail on our universe. But, we do have direct experience with minds.

  • The cause of the universe is a transcendent, immaterial, timeless Mind.

"You can think of the universe as a kind of artifact and that artifact points to a designer. If you add to this the evidence for a beginning to the universe from another session, the cosmological argument, then you have a cause of the design already available to you. So if you already accept the cosmological argument there's a cause waiting in the wings to employ in explaining the design of our universe ... the fine tuning. The cause of the universe must be a designer who is transcendent, immaterial and a mind that exists in a timeless eternity and I think that is quite consonant with the Christian idea of God."

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