In
order to understand the sophistry of Neil deGrasse Tyson's recent
comments on the universe, we must look at the fascinating issue of
cosmic fine-tuning. Let's start at the beginning of time.
Astronomers say that the universe suddenly began in the unexplained
event known as the Big Bang, in which the universe suddenly began to
expand from an infinitely dense point. Decades ago, cosmologists
figured out that the initial expansion rate of the universe must have
been fine-tuned to at least fifty decimal places, with what is known
as the critical density exactly matching the actual density to fifty
decimal places. You can do a Google search for “flatness problem”
to find many sources stating this. There's a theory (or a family of
theories) called the cosmic inflation theory designed to explain away this
astonishing correspondence. But that theory requires a great deal of
fine-tuning itself, in many places (as discussed here). So it's not clear that you end up
with less fine-tuning if you believe in such a theory. Regardless if
whether such a cosmic inflation theory is true, we can say that the
universe's beginning was astonishingly fine-tuned, and that an
incredibly tiny change in the Big Bang would have meant that we would
not have ended up with a life-compatible universe such as we live in.
(Universes that expand too fast don't form galaxies, and universes
that expand too slow have their matter all collapse into black
holes, or one big black hole.)
So
the Big Bang was very fine-tuned, but we also find abundant and very
precise fine-tuning in the fundamental constants of the universe. A
dramatic example (another case of two numbers coincidentally matching
to many decimal places) is found in the charges of the proton and the
electron. Each proton has a mass 1836 times greater than each
electron, and so you might think that each proton has an electric
charge much greater than each electron. But no, we couldn't exist if
that were the case. Instead each proton has a charge exactly the same
as each electron, the only difference being that the sign of the
electron charge is negative. The exact equality of the proton charge
and the electron charge has been measured to 18 decimal places. We
know that planets like the earth would not even hold together if the
electron charge and the proton charge differed by even 1 part in
1,000,000,000,000,000,000,000,000,000 (as discussed by a scientist quoted here).
There
are still many other cases of fine-tuning in the universe's
fundamental constants. One is the astonishing case of the
cosmological constant or vacuum energy density, where we see that
nature seems to have miraculously balanced the books to 60 decimal
places. This is again something on which our existence depends, because
if things were not so precisely balanced, ordinary space would have
more mass-energy than steel, as discussed here. There are also reasons why we would not
be here if the gravitational constant were a little bit different, or
the strong nuclear force were a little different, or the fine
structure constant were a little different.
The
following visual illustrates how right things have to be in order for
creatures such as us to exist. Imagine someone pulling the lever on
this slot machine. In order for you to get the jackpot (the
appearance of life), you have to get a coincidental match on each of
the rows. The chance of this happening is almost infinitely small. (This post discusses the particular items in this visual, and why each is extremely unlikely to be coincidentally compatible with life.)
The
“lucky numbers” are only half the story, for in order to have
life the universe also needs lucky laws, such as strange quantum
mechanical laws assuring that electrons don't fall into the atomic
nucleus, lucky laws of electromagnetism that assure that chemistry
can take place, lucky laws of nuclear physics assuring that an atomic
nucleus can hold together, other lucky laws of particle physics restricting the number of types of stable particles to only a handful, and a lucky Pauli exclusion principle
allowing for solid matter.
So
the evidence for cosmic fine-tuning is immense. This evidence has
been widely discussed by scientists over the past few decades, often
in discussions that used the word “anthropic.” So when Neil
deGrasse Tyson was asked about this question, we expected to hear
from him some substantive comments. Instead we got the following
reasoning:
I
look out to the universe and yes, it is filled with mysteries, but
it's also filled with all manner of things that would just as soon
have you dead. Like asteroid strikes, and hurricanes, and tornadoes,
and tsunamis, and volcanoes, and disease, and pestilence. There are
things that exist in the natural world that do not have your health
or longevity as a priority. And so I cannot look at the universe and
say that yes, there's a God, and this God cares about my life -- at
all. The evidence does not support this.
This
reasoning can be summarized like this: there exist various forms of
death, so there does not exist a God who is interested in you living.
This is, of course, a very bad argument. The evidence that we have
is entirely consistent with the idea that there exists some higher
power who wants beings such as you to exist (and who set up the
universe so that you and similar beings would exist), but who does
not want you to live forever in a physical existence on this planet
(something which would cause various problems such as extreme
overpopulation and cultural stagnation). The existence of various
forms of death do nothing to argue against such a possibility. Since
such a possibility is strongly suggested by abundant evidence of
astonishingly precise fine-tuning in the universe, it would seem to
be very well supported by evidence. The claim “the evidence does
not support this” is very misleading in this case. To the contrary,
there is a great mountain of evidence that Tyson has done nothing to
explain away.
At
the core of Tyson's statement is a most absurd non-sequitur.
There
are things that exist in the natural world that do not have your
health or longevity as a priority. And so I cannot look at the
universe and say that yes, there's a God, and this God cares about my
life -- at all.
So from the fact that there are things in the natural
world that “do not have your health or longevity as a priority”
we can conclude there is no God? Asteroids don't care about us, so
there is no God? That's a ridiculous argument.
Tyson's argument is similar to arguments like this, and
every bit as fallacious:
Somebody died in the house, therefore nobody built
the house.
The
house was hit by an earthquake, therefore nobody built the house.
Another
related comment was this one by Tyson.
I
think of, like, the human body, and I look at what’s going on
between our legs. There’s like a sewage system and entertainment
complex intermingling. No engineer of any intelligence would have
designed it that way.
I cite this merely as an example of how absurd Tyson
gets when he starts reasoning about theological topics. There is no
sound basis for complaining about the design of the human penis on
the basis Tyson has given, and I know of no male other than Tyson who
has ever complained about the same organ being used for sex and
urination. It is generally regarded as being a sign of good design
when a designer gives a single object two capabilities – for
example, no one complains that hammers are poorly designed because
they can both hammer nails and remove nails. We also do know of intelligent
designers who combine a waste disposal system and an entertainment
complex. That is done by every architect who designs a movie
theater, and includes bathrooms in the design.
Having assumed the job of educating the public about the
universe, Tyson should be educating the public about one of the top
developments of cosmology during the past 30 years, the fact that
scientists have found countless ways in which our universe is
astonishing fine-tuned. But when Tyson had 13 hours of television
time in his series Cosmos, he found time to discuss all kinds
of unimportant digressions, but apparently neglected to even discuss
the evidence that our universe is exquisitely well-calibrated for
life. (I am judging from this lengthy summary, which makes no mention of
such a topic.) Tyson is also director of the Hayden Planetarium, but nowhere in its vast exhibit spaces is the visitor informed about this very important conclusion of modern cosmology.
It would seem that Tyson doesn't want you to know about
all the ways in which our universe is fine-tuned for life (in
repeated defiance of enormous odds), because that might mess up
Tyson's gloomy type of talk that emphasizes a universe “filled
with all manner of things that would just as soon have you dead,”
a thesis we might describe as “the universe is trying to kill
you.” Neil apparently doesn't want you to think about how
perfectly balanced the electrical charges in your atoms are (in a
coincidence we would expect to find in less than 1 in
1,000,000,000,000,000,000 random universes, the coincidence
of the proton charge exactly matching the electron charge to
eighteen decimal places, despite the proton mass being 1836 times
greater than the electron mass). Neil would probably be much happier if you fret about some
asteroid that has maybe 1 chance in a million of killing you. I may
note that it doesn't make sense to cite asteroids as evidence that
the universe is stacked against us. A future generation of
asteroid-mining humans (with the power to deflect asteroids) may
regard asteroids as one of the greatest blessings of the solar
system.
Postscript: See here for a recent post on the Scientific American web site that discusses aspects of cosmic fine-tuning. Some of the points made are below.
The constants of nature—such as c, the speed of light, and G, which denotes the force of gravity—seem to be fine-tuned for our existence. Just a slight variation in one of these values would render galaxies, stars, planets, life and even complex atoms like those that comprise your pumpkin pie impossible...Scientists also observe a fine-tuning within the physical laws themselves—the rules, such as the laws of gravity and thermodynamics, that regulate the cosmos.
Postscript: See here for a recent post on the Scientific American web site that discusses aspects of cosmic fine-tuning. Some of the points made are below.
The constants of nature—such as c, the speed of light, and G, which denotes the force of gravity—seem to be fine-tuned for our existence. Just a slight variation in one of these values would render galaxies, stars, planets, life and even complex atoms like those that comprise your pumpkin pie impossible...Scientists also observe a fine-tuning within the physical laws themselves—the rules, such as the laws of gravity and thermodynamics, that regulate the cosmos.
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