Life on Earth: Chance or Deliberate. A Reply

I read a recent Chowk article, "Life on Earth: Chance or Deliberate" by Omar Phoenix , and was, in general, disappointed. Since this article was by an aspiring young scientist, I was disturbed by the lack of respect it showed for the scientific

contributions of other cultures. It also had several scientific inaccuracies and, in general, lacked a basic understanding of the scientific process.

Lets look at some of the claims in the article:

I. "Greek science speculative ... and lacked working out and hard core

evidence".

The author of the article used one sentence from a Greek scientist to label the contribution of all Greek scientists, spanning seven hundred years, as speculative. On the contrary, it is the Greeks who laid the foundation of logic and science.

Science is a continuing human endeavor. No one culture can claim its ownership. Like all of the later civilizations of the world, the Greeks benefited from the works of civilizations that existed before them. The Greek contribution to science was only possible because of earlier efforts of Egyptian and Mesopotamian civilizations (3000-1000BC) and their influence on the Greek science and culture is obvious. Perhaps, given enough time, other cultures

(like the ancient Chinese and Indian civilization) would also have stumbled on to the basic principles of modern science and logic, but the Greeks were fortuitous to have just the right elements at the right time to lay the foundation of modern scientific thinking.

I will not go into the details of every single Greek achievement. People interested in the scientific contributions of Greeks should read "Ancient Greece: Through the Golden Age of Greece" by George Sartan, and "Greek Science in Antiquity" by Marshall Clagatt. However, I will mention at least a few cases which completely contradict the claim that Greek science was speculative.

In the third century B.C., the director of the great library at Alexandria, Eratosthenes, came to know of a well at Cyenes that did not cast any shadows at noon on June 21st. Cyene was located about 800 km from the city of Alexandria. He postulated that if the Earth is flat then, at any given time, the rays from the Sun should hit all places of the Earth at the same angle. If a stick at Cyene does not cast a shadow at noon on June 21st, then it should not cast a shadow at Alexandria either. He performed this experiment and discovered that a stick at Alexandria indeed cast a shadow, leading him to believe that the Earth is round. From the distance between Cyene and Alexandria, and the length of the shadow, Eratosthenes was able to get an estimate of the circumference of the

Earth. His answer is within a few percent of the correct measurement!Speculative thinking?

A friend of Eratosthenes, Archimedes, addressed the issues of hydrostatics in "On Floating Bodies". This book also includes the well known 'principle of Archimedes', which is still taught in schools after almost 22 centuries. He is also famous for running naked from the bath tub to his home, shouting "Eureka!", when he discovered that he could use the basic principles of hydrostatics to determine whether King Hiero's crown was made of pure gold or not.

Aristarchus of Samos, also in the 3rd century B.C, used the size of the Earth's shadow on the Moon during a lunar eclipse, to deduce that the Sun had to be much larger than the Earth, as well as very far away" ("Cosmos" by Carl Sagan). He also argued that the Earth revolved around the Sun and not the other way around. Why did it take almost 2000 years for the acceptance of this idea? Greek scientists were smart. They knew that if the Earth was revolving around the Sun, then the relatively nearby stars should appear to move with respect to the distant stars, an effect known as parallax. However, when they tested

this idea with observations, they did not find any noticeable parallax leading them to believe that the Earth is stationary. As it turns out, their idea was very sound, however, even the nearest star is so far away that it is impossible to measure its parallax without a telescope. In fact the first parallax was not measured until the 19th century. It then became clear from straightforward Greek geometry that the stars were light years away. This example illustrates the Greek tendency to form a hypothesis and to test it through experimentation, the underlying principle of modern science.

Muslim scientists of the middle ages duly acknowledged the contributions of the Greek scientists. Most of the Greek manuscripts were translated and preserved by the Muslims. Almagest ("the greatest") of Ptolemy is certainly the most well known of these Greeko-Roman translations. These documents, along with the works of Muslim scholars, got back to Europe through Spain in the late-middle ages and sparked the renaissance. Ironically, a number of these original documents of the Muslim scholars (e.g. Ibn-e-Rushd (Averros)) can only be found in the Western libraries (See "Muslims and Science" by Pervez Hoodbhoy).

II. "...atheist scientists who believed that everything in this

universe was a mere coincidence.."

If the universe is only governed by coincidences, then it would be impossible to learn anything about it. Fortunately, this is not the case. Unthinking belief in coincidence is, in fact, the antithesis of science.

Almost 2,600 years ago, on the Greek island of Samos, a revolutionary idea developed that the universe has an internal order. Instead of being capricious and arbitrary, the nature of the universe is knowable. This is a key moment not only in the development of science and logical thinking, but in the history of mankind. "This ordered and admirable character of the universe was called Cosmos" (For a lively introduction to Samos and the Ionian science, see chapter 7 of "Cosmos" by Carl Sagan).

Science is the pursuit of understanding the physical processes that govern the cosmos. If the universe was directly influenced by an arbitrary power(s), then it would have been impossible for science to have progressed. Imagine a universe where one day the energy is conserved and the next day it is not. Sometimes the force of gravity is attractive and at others it is repulsive. Without any reason, the light in vacuum sometimes travel at 1000 miles per second and at others at 186000 miles per second. Science in such a universe

would be impossible.

An orderly universe does not necessarily mean that a person has to renounce her or his faith in God. Nature follows physical laws. Everything has a reason. An apple just does not fall from the tree. It falls because of the gravitational force of the Earth. This is a fact. Whether a person believes in God or not, the apple will accelerate towards the Earth at 9.8 meters per square seconds. One can still believe that physical laws are set by a transcendental power. This

is faith. However, personal beliefs do not change the nature of the physical universe.

Lets look at another example which was mentioned in Pheonix's article. It was stated that the universe is symmetrical and except for the slight dominance of matter over antimatter, everything in the universe would have annihilated itself. It was suggested that the reason is "unknown" and the author was left "to wonder why", implying the direct hand of the Creator in creating this

asymmetry.

First of all, the ratio of matter/antimatter quoted in the article (7:3) is inaccurate. The observed ratio, from the clusters of galaxies, is close to 10^6:1, or 1 anti-particle for every million particles (See pg. 456 "Principles of Physical Cosmology" by Peebles). Now there are three ways to approach this problem: a) This asymmetry is only due to a "Creator", b) It is caused by a physical process, and c) the Creator used a physical process to create

this asymmetry.

If a) is the answer, then it makes the universe arbitrary and unknowable. We will exclude this case since we are assuming an ordered universe. The second choice can lead to the reasons for this asymmetry and would naturally beg the next logical questions: what is the process that has created this asymmetry and how does it work? Answers to these questions would lead to further questions. This is an example of how science works. The third choice can also be successful provided it excludes the possibility of an arbitrary intervention and only seek the physical processes set by the Creator. The last two approaches can potentially lead to an understanding of this asymmetry. This makes the assumption of the presence of a Creator optional and not a "logical

conclusion". This gives faith its real meaning.

As it turns out, the decay of elementary particles called Kaons violates charge-parity, leading to a slight difference in the decay rates of Kaons and anti-Kaons. Most scientists believe that this asymmetry is responsible for the dominance of matter over anti-matter. Now the focus of this field has mostly shifted to the reasons for this asymmetry in the decay rate (see ch. 6 of "The Inflationary Universe" by Alan Guth). James Cronin and Val Fitch were awarded the Nobel Prize for leading a team that confirmed the Kaon decay results at the

Brookhaven National Laboratory. Alas, this problem would have remained a mystery had they accepted an arbitrary reason for the matter-antimatter

asymmetry.

III. The Great Demotion:

Ever since Copernius, the perceived importance of humans in the universe has taken one blow after another. From being located at the center of the universe, we have been demoted to a third planet orbiting an ordinary star. Our star is only one of 400 billion stars in the Milky Way Galaxy and is located on a spiral arm in the outskirts of our galaxy. There are more than a hundred billion galaxies in the universe each containing approximately a hundred billion stars. Removing humanity from the center of the universe to the most inconspicuous of places, has been a great demotion.

Some people have been reluctant to accept this reality. Phoenix, in his article, made arguments regarding the precise nature of the carbon atom, the

expansion of the universe, the properties of sub-atomic particles etc. being essential for the existence of life, and hence it proves the existence God. The arguments of the author are largely based on the Anthropic Principle which states that had any of the above mentioned properties been different, or had the fundamental constants been slightly different, there would not have been any

life. Hence this universe has been fine tuned just for the purpose of supporting humans.

This is a big leap of imagination! First of all, by most accounts the Anthropic Principle is not considered scientific, as it fails to provide any testable hypothesis, one of the key requirements of science (See chapter 26: "Anthropic Principle" in "Cosmology" by Noriss Hetherington). Indeed, there can be billions of other universes which don't have life...and similarly there can be billion others which could harbor life (albeit a very different kind of life) out of a different combination of fundamental constants. Indeed, the inflation theory of the universe predicts an extremely large number of parallel

universes originating from the quantum chaos.

Consider the example of polar bears. They can only survive in the cold climate and we only find polar bears in the cold regions. Does this mean that the cold regions are designed solely for the existence of polar bears? Indeed, an anthropic principle for polar bears would suggest just that. However that is not the case as is illustrated by the presence of other animals in the same regions. The reason why polar bears exist only in cold regions is because they can adapt well to that climate. Animals that could not adapt to these conditions died. There are numerous other species on Earth that have perished because they were unable to adapt to the changing climate. Similarly, the fact

that we have survived in our universe does not mean that we are the sole purpose of the universe.

IV. "Earth just happens to be at the right distance from the Sun to

have a temperature range where water can exist in all three states.."

Interestingly Europa, located five time further away from the Sun than the Earth, has a tremendous potential to have liquid water underneath its icy surface. It is suspected that Jupiter's tidal forces keep the interior of the planet warm enough to keep the water in liquid form. In fact the conditions in Europa's oceans might be identical to the volcanic vents here on Earth and may even harbor life.

The nature does not need a "trillion gazillion" planets to form life. It is suspected, and scientific investigations are underway, that life may have originated on Mars first. A meteor or an asteroid impact on Mars, could have ejected life-rich rocks into space and some of these rocks may have seeded the Earth with early life. The discovery of possible micro-fossils in the Martian meteorite, ALH840001, in 1996, further supports the view that Earth may not have been the only planet in our solar system, where life may have flourished. Similarly, comets are rich in water and organic compounds -- the raw materials needed for the origin of life. We also know that the impact of comets were a lot

more common in the early days of our solar system, providing a way of transporting these organic-rich materials to several other bodies in our solar system.

Until very recently, many people believed that our solar system is special because it has planets. The discovery of planets around other stars have, once again, demonstrated that we do not live in a special place. One of the planets discovered so far is, in fact, orbiting its star at a distance at which water can stay in liquid form. Astronomers are now detecting several new planets a year and we have just started to scratch the surface. Thus, we may have only a

few more years to live in the comfort of believing that life, in the entire universe, originated only here on Earth. What happened here on Earth, regarding the origin of life, must have happened on countless other worlds. The discovery of a single micro-organism outside Earth would deprovincialize biology and its impact would be comparable to the reshaping of our universe by Copernicus. And that day is, hopefully, not that far away.