The Life of the Cosmos has ratings and 42 reviews. David said: Lee Smolin presents an interesting hypothesis that attempts to explain why the fundame. CHAPTER ONE. The Life of the Cosmos. By LEE SMOLIN Oxford University Press. Read the Review. LIGHT and LIFE. Science is, above everything else. The life of the cosmos / by Lee Smolin. p. cm. Includes bibliographical references and index. ISBN X. ISBN (Pbk.) 1. Cosmology.
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T he physical world is oife by forces. They control the behavior of everything: Gravitation propels our Earth around the Sun and causes the Universe to expand. In ancient times, Greeks imagined that the whims of gods determined the fates of humans.
In modern times, scientists tell us that forces do the same.
Science — for the most part — is a description of how nature works. Lifs can compute the trajectory of a missile using Newton’s laws of motion or the rate at which a nucleus disintegrates. Paleontologists have mapped out a sketchy, but impressive, three-billion-year-long picture of how the human has arisen, starting from a microbe, evolving to a worm, growing into a fish, emerging as a tetrapod on land, and changing into a mammal, then a monkey, then a man.
But science in its present form fails to explain why things are lifs way they are — cosoms least at a fundamental level. Why is matter made up of only quarks the constituents of the protons and neutrons that compose the nuclei of atoms and leptons electrons and neutrinos?
Why are there only four fundamental forces and why do they act the way they do? Why does the Universe have stars and galaxies? Why does it have planets and life? Should Nature coosmos the laws of physics to mankind like God presented the Ten Commandments to Moses? While some theorists are hoping to obtain a more fundamental explanation of the world, the question “Why?
For example, string theory is a speculative, ambitious idea that attempts to unify all matter and all forces into a single structure. If true, it represents a great simplification in our live of the world and a great triumph of theoretical physics.
But the question still will be “Why strings? One way to answer the “why?
The Life of the Cosmos
Lee Smolin in his book The Life of the Cosmos is quick to dismiss. Lwe, many scientists are reluctant to bring a supreme being into the picture for several reasons basic to the scientific methodology: Someone might even dare to say “Why God? In The Life of the CosmosDr. Smolin attempts to answer why our Universe is the way it is through a new idea called the cosmological natural selection principle. He uses processes and NOT equations to try to accomplish this. Our existence is explained in terms of history rather than by general principles.
Cosmological natural selection is an extremely ambitious proposal, comparable to the one of Copernicus at his time that the Earth was not the center of the Universe. Copernicus, of course, was right. However, for every “Copernicus,” there are a hundred scientists who have made bold proposals that have turned out to be wrong. The reader may not realize this because the names of scientists who fail are soon forgotten. So if Lee Smolin is correct, his name will be added to the short list of scientific greats.
If not correct, he joins a longer list of unknowns who had imaginative ideas that failed. In fact, many scientists think that Smolin’s theory has only a low th of being correct.
The Life of the Cosmos by Lee Smolin
In the days of Copernicus, the Earth was the center of the Universe or it was not. Setting human biases aside, Copernicus had a chance of being right. In the case of Smolin, the chances of being correct might be 1 in 2 40or about 1 in a trillion pf the discussion below. Smolin’s proposal, a product arising from philosophy, is speculation.
In his book, he explicit states this to the reader and he should be commended for doing so. Some scientists write books claiming their “pet theory” to be the accepted truth. Such a practice is misleading and does a disservice to the pursuit of increasing public understanding of science.
Early in his book, Dr. Smolin awakens us to the fact that we live in an improbable universe. There are dozens of parameters pertinent to our world. These parameters are numbers, such as the masses of particles and the strengths of forces, that can in principle be varied.
Thus the world could be different: Have these parameters been set to special values that make our Universe rich, complex and interesting? In a different universe with a different set of physical laws, structures such as planets, stars and galaxies might not form, and the same might be true for life.
Smolin estimates that the chances that the parameters assume the values of our Universe are 1 in 10 — this probability is a number that begins with a decimal point, is followed by zeros and ends with a 1, an extraordinarily small chance. It is thus surprising that our Universe is so interesting.
What could be the explanation of this miracle? Lee Smolin offers three answers: Some scientists — particularly string theorists – – would vote for explanation 2. Many scieentists would simply “throw their hands up” saying the world is simply the way it is. This, of course, is not an explanation, but some might say that perhaps there is no explanation. Smolin dismisses these responses as well as 1 because 3 can be so simple. He also rejects explanation 2 for the following reasons.
First, finding a unique theory does not explain anything at a fundamental level — it is almost like God presenting the world with a slab of natural commandments. Second, a unique theory is unlikely to yield the parameters of our Universe so the chances that it exists is 1 in 10 Third, even if string theory is correct, there are countless ways for it to manifest itself in scientific jargon these manifestations are called vacuum configurations.
String theory offers no explanation of why our Universe “has picked” one manifestation over another. One may try to question whether our Universe really is improbable. Maybe one day, physicists will achieve an understanding that does explain the values of Nature’s parameters in a simple way. Or maybe with other values of the masses of particles, the strengths of forces and so on, a universe arises that is very different from ours but still possesses rich and complex structures.
In such a hypothetical world, there might be complex self-organizing units that mimic what we call life. It may be that, although our Universe is special in its particular realization of the consequences of its physical laws, that complexity and self-organization are a property of many systems. But all this is speculation and, until otherwise shown, one probably should accept the conclusion that we live in a highly improbable universe.
Thus the “why” question becomes more intriguing: Earth has sophisticated life. The chances of randomly throwing organic molecules together to produce a mammal is virtually zero.
One might then conclude that the mammal is a miracle. We know that this is not the case. Sophisticated creatures exist because of evolution. Given the right environment and enough time, randomly combining organic molecules can produce primitive microscopic life. That is how life on Earth began. Evolution and billions of years allowed organisms to develop into complicated, macroscopic forms.
Smolin speculates that an analogous process must have taken place for our Universe. The proposal for cosmological natural selection rests on two general assumptions: I There are many universes that can give rise to new universes and II the laws of Nature are mutable. These ideas may seem astonishing to the reader, but theorists have often contemplated them.
Before the twentieth century, it was thought that all the stars in the night sky formed one entity. It was not until the ‘s that Edwin Hubble, using a newly constructed powerful telescope, viewed a hazy object in the constellation Andromeda and resolved it into countless points of light — they were stars. Hubble had discovered a galaxy. Suddenly there were two worlds: Soon other “worlds” were observed. Nowadays, astronomers estimate that there are roughly ghe billion galaxies in the visible Universe, that is, that part of the Universe for which light has had enough time to reach us on Earth.
The revelation of the existence of other galaxies naturally leads to the question “Are there also other universes? One popular, as-of-yet-unconfirmed theory of cosmology — known as inflation — says that the Universe underwent a tremendous expansion when it was a ccosmos of a second old.
What does it mean for the Universe to expand? According to Einstein’s general theory of gravity, space is dynamical — it can stretch, bend and twist. Astronomers have discovered that distant galaxies are all moving away from one another.
Most versions of inflation predict the existence of other universes. These are other worlds, completely disconnected from ours.
Cosmological natural selection (fecund universes)
Many scientists do not like this idea because one would never be able to observe these other universes. Near the very beginning of time, gravity was in its quantum phase. Although the consistent quantum theory of gravity is not yet known, some cosmologists believe that a multi-universe picture of the world will emerge as part of quantum gravity.
All this is speculation, of course. But the situation is probably similar to the one of Copernicus discussed above.
Given our ljfe, there is probably a chance that other universes exist. Theorists have also considered part of assumption II that Nature’s parameters might be subject to change.