Look But Don’t Touch

When it comes to analyzing the universe, astronomers are at a distinct disadvantage to almost any other scientist.  Geologists can take samples of the Earth and subject it to any number of tests, chemical, physical and otherwise.  Archaeologists dig up ruins and examine them carefully.  Biologists can dissect plants and animals to see what makes them tick.  But astronomers can only look.  And what they are looking at isn’t even the way things are today; they are looking into the past.  Because of the finite speed of light and the immense distances to stars and galaxies, the light (when I use the term “light” I mean to include all wavelengths in the electromagnetic spectrum, including radio waves, microwaves and x-rays as well as visible light) that reaches Earth started out thousands or millions of years ago.  As long as we are fixed on Earth we’re constrained to looking backwards in time.  We will never see things as they are.

In order to understand various theories on the age of the universe it’s necessary to understand a little about how physicists used light to measure distances and ages of stars and galaxies.

Ancient man knew that thunder and lightning occur at the same time but there is a lapse of time between the lightning flash and the sound of thunder.  He therefore concluded that sound travels slower than light.  How much slower and, more importantly, what was the speed of light, remained unknown.  Galileo proposed an experiment where two people with lanterns stood some distance apart.  One would uncover his lantern and as soon as the other saw the light he would uncover his.  By knowing how far apart the two people were and measuring the elapsed time, the speed of light could be calculated.  Unfortunately Galileo was in exile and blind by then and was never able to conduct his experiment.  A quarter century after his death the experiment was done but due to the real speed of light all that could be determined was that its speed is somewhere between 10,000 km/sec. and infinity.

A few years later a Danish astronomer, Ole Romer, was able to determine that, though high, the speed of light is finite.  He did this by scrupulously observing the position of Io, one of Jupiter’s moons.  Romer assumed that Io circled Jupiter in a regular orbit.  However sometimes it appeared earlier than expected and sometimes later.  Romer realized that it appeared later when Earth and Jupiter were on opposite sides of the sun and earlier when both were on the same side of the sun.  When Jupiter and Earth were on opposite sides of the sun the light from Io would take longer to arrive at Earth than when they were on the same side of the sun because of the additional distance only if light has a finite speed.  After three years of work Romer came up with an estimate of 190,000 km/sec (118,750 miles/second).  The exact speed is closer to 300,000 km/sec (187,500 miles/sec) but the important point is Romer established that the speed of light is finite.

The next big question didn’t take long to arise.  How is light propagated?  Light was assumed to be some sort of a wave, but waves need something to move through.  For example, water waves move through water.  Sound waves move through air, water, solids and a lot of other media.  It had been shown that if an alarm clock was put in a bell jar and the air was sucked out, resulting in a vacuum, there was no sound.  Thus sound, like water waves, needs a medium through which to travel.  But light could also travel through a vacuum.  So how was light transmitted?

To answer this question, like millions of other people, scientists made an assumption, one that, like millions of assumptions made by ordinary people, turned out to be unfounded.  They assumed that space is filled with a luminiferous ether or simply ether. The ether was supposed to be something that could vibrate 40 million million times per second yet had almost no density.  It was fully transparent, frictionless, and  inert.  It was everywhere and yet nowhere because no one had ever seen it.  In retrospect it sounds a bit like some descriptions of God.

It would take a couple hundred years before the United States’ first Nobel Laureate in physics, Albert Michelson, proved that the ether doesn’t exist while trying to prove that it does.  But that’s the subject of another post.

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The Ultimate Question

The sun-centered solar system model began to attract converts and the Church started to realize that it would look foolish if it continued to oppose what a majority of the world viewed as reality.  In the Eighteenth Century it relaxed its position on scientific inquiry and a new era of intellectual freedom opened.  Despite advances in biology, chemistry, mathematics and even physics, one question remained the elephant in the room that everyone ignored: how was the Earth (and, by extension, the universe) created?  There were two main reasons for avoiding this question.  First, science confined itself to explaining natural phenomena and the creation of the Earth was widely viewed to be supernatural and therefore beyond the ken of science.  Secondly, poking around in this area might, it was thought, upset the mutual respect and relatively stable truce that existed between science and religion.  No one wanted a return to Galileo’s time.

Actually, the question was even narrower than how the Earth was created.  Most scientists still accepted the Biblical version of creation by God, reducing the question to when did God create the Earth, not how or even did He.  Scholars combed through the begats of Genesis, counting years trying to set a precise time for In the beginning.  The markers in the Bible are sufficiently vague that differences of a few thousand years showed up.  Alfonso X of Castile determined a date of 6904 B.C. while Johannes Kepler found a more recent date of 3992 B.C.  Probably the most thorough search was made by James Ussher who later became Archbishop of Armagh.  He used agents in the Middle East to search out and obtain ancient Biblical texts so as to reduce errors caused by translation.  He made a huge effort to link Old Testament chronology to that of the secular world.  Eventually he discovered that Nebuchadnezzar, who is mentioned briefly in Second Kings, is also mentioned by Ptolemy in a list of Babylonian kings.  He was thereby able to anchor at least one Biblical date to a non-Biblical historical record.  Ussher arrived at an age of 4004 years for the Earth.  He went even further and declared that the creation began at 6:00 p.m. on October 22, 4004 B.C.  His date was accepted by the Church of England and was included in the King James version until into the Nineteenth Century.

Science was generally happy to accept Ussher’s date mainly because there was no evidence to the contrary.  However, when Charles Darwin proposed his theory of evolution by natural selection, it soon became apparent that this theory could not fit into a world that was only a few thousand years old.  Natural selection is an agonizingly slow process, one that could not possibly have resulted in the complex life forms found on Earth today in less than 6,000 years.  Science could not afford to ignore Darwin’s theory.  Yet it couldn’t accept the theory and the age of the Earth, so it turned to a scientific examination of the age of the Earth.

Victorian geologists used what they calculated the rate of sedimentary deposits to be to arrive at an age of several million years.  Lord Kelvin assumed that the Earth began as a molten ball and calculated it would take 20 million years for the Earth to cool to its present state.  A few years later John Joly began by assuming the oceans started out pure and calculated how long it would take to arrive at their present salinity, resulting in an age of about 100 million years.  In the early 20th Century scientists were able to use radioactivity to estimate the age to be 500 million years.  Refinements in this technique led to an estimated age of over a billion years by 1907.

The dating game was on.

And God Said: “Let There Be Newton”

The same year that Galileo died in Florence, a premature baby was born to the Newton family in Lincolnshire.  Isaac, as he was named, was a sickly child and picked on in school.  The school bully, who also happened to be the smartest boy in school, once kicked Newton in the stomach.  Newton fought back and beat the bully.  He then proceeded to complete his victory by beating the boy in school.  At age 18 he entered Trinity College and earned a B.A. degree in mathematics without much distinction.

During Newton’s studies in college, the Black Plague ravaged England and all students were sent home.  Newton returned to Lincolnshire where the family lived in seclusion for about 18 months.  During that time Newton conceived almost all of the ideas for which he is famous.  These include the binomial theorem that is taught in high school algebra, the fundamentals of differential and integral calculus, which he called fluxions and inverse fluxions, a theory on color, that is, the spectrum that creates rainbows and an extension of his theory of gravity as being the force that keeps the moon in orbit around the earth.

Over the next twenty years Newton worked on his Mathematical Principles of Natural Philosophy, natural philosophy being the term then given to the laws of nature.  Newton developed a mechanistic interpretation of all physical phenomena, a point of view that dominated physics until the early years of the Twentieth Century when the general theory of relativity and quantum mechanics were developed.  However, Newton’s laws and theories, which have come to be called Newtonian or Classical Physics, still govern the ordinary world around us.  They explain why cars stay on the roads, why roller coasters can go upside down, and why there are rainbows after a rain storm.  The development of his theory of gravity led to a new field of study, celestial mechanics, which in turn advanced astronomy and the study of the cosmos.

It was Newton who first conceived of a satellite orbiting the earth.  He did this by observing that a stone thrown from a high point makes an arc as it drops back to earth.  He then imagined throwing the stone harder and harder, so that the arc was longer and longer until eventually the stone passed the curvature of the earth before it struck ground, thereby entering into orbit around the earth.

As a person, Newton wasn’t particularly pleasant and was often involved in controversy with his colleagues.  He was the arch-type of the absent-minded professor, often forgetting to eat, comb his hair or even complete getting dressed in the morning.  He had a cat, for whom he cut an opening in his door so the cat could come and go at her leisure.  When the cat had kittens, Newton cut holes for each kitten.  He was, however, aware of the achievements of those who came before him.  He famously remarked “If I have seen further than others it is because I stood on the shoulders of giants.”

Newton is arguably one of the best-known scientists of all time.  The names Newton and Einstein are linked in physics and just as almost everyone knows E=mc2 as the formula that converts mass to energy and vice versa, almost everyone is familiar with Newton’s laws of motion, particularly the Third Law, to every action there is an equal and opposite reaction.

It is safe to say that Newton is the giant on whose shoulders all physicists who followed stood.

 

The Sun Revolves Around the Earth

At least since the time of Ptolemy, a Greek astronomer who lived in the first half of the Second Century A.D. until 1543 when Nicholaus Copernicus published De Revolutionibus Orbitum Coelestium man believed the Earth was the center of the universe, which at that time consisted of the sun and a few planets and stars that could be seen with the naked eye.  This was understandable because the sun appeared to rise every morning in the east, cross the sky and set in the west.  Copernicus challenged the earth-centric notion of things by postulating that the sun was the center of the solar system and that Earth and the other planets revolved around it.  So as not to offend the Church (that is, to avoid banishment), his book contained a disclaimer to the effect that his theory was more of a mathematical exercise than a statement of the way things are.

Copernicus believed that the planetary motions were circular, a throwback to the old Greek view that the circle is the most perfect geometric shape.  Another astronomer of the same time, Johannes Kepler, found that this view didn’t match the observations of a third astronomer, Tycho Brahe.  Kepler worked out the laws of planetary motion which predict that planets orbit the sun in elliptical shape, moving between two points of proximity to the sun, aphelion, when they are nearest to the sun and moving fastest, and perihelion, when they are farthest and moving slowest.

Approximately the same time, Galileo Galilei dropped out of medical school and began studying dynamics, the laws of moving bodies, which is now called mechanics.  He developed an early theory of relativity by questioning whether a stone dropped from the top of a mast of a moving ship would hit the base of the mast or would have the ship move under it and strike nearer the stern of the ship.  The latter result was predicted by Aristotlean theory, which said that the stone would stop moving as soon as it was released.  This was debated for years without anyone bothering to actually drop a stone from the mast of a ship.  Three centuries later Einstein extended this theory of relativity to electromagnetic waves.

By the age of 40 Galileo was engaged in astronomy, looking at stars through the newly-invented telescope.  He predicted that a bright light in the sky, something we now call a nova, would eventually fade and disappear.  This brought him under scrutiny by the Church, which viewed any change in the heavens as contrary to God’s work that is unchangeable.  Galileo went blithely on without regard to growing animosity and eventually confirmed Copernicus’ theories of planetary motion around the sun.  For his effort, in 1633 at age 69, he was brought before the judges of the Holy Office of the Church and “confessed” to heresy.  He was confined to his villa, essentially under house arrest, until his death in 1642.

Galileo’s experience with religion, and that of others over the centuries, undoubtedly spawned the tension between science and religion that continues even to today.  Stephen Hawking wrote in his book A Brief History of Time, that he and other physicists once had an audience with the Pope in which the Pope, apparently wanting to avoid another incident like Galileo, told the group that there was nothing wrong with trying to figure out how the universe began, but to leave alone anything that occurred before the Big Bang, as that was the work of God.  It is no wonder, then, that scientists cannot bring themselves to offer any hypothesis that includes any kind of Creator.

The Big Bang

The Big Bang Theory (the real scientific theory, not the TV show) is pretty well ingrained in the public consciousness.  Most people have a general idea what “the Big Bang” means.  In a nutshell, the theory is that everything began with a huge explosion somewhere around 14 billion years ago.  Everything that’s out there came from that.  Beyond that, most people don’t know what happened.  A mistaken conception exists that the stars, galaxies and planets, including Earth, popped into existence fully formed.  The real story is a little more complicated and a little more detailed.

Before examining the Big Bang Theory, we need to understand just what a theory is.  A theory is a guess as to how to explain what is observed.  For example, thousands of years ago, observation that the sun came up and appeared to travel across the sky led to a theory that the sun revolved around the earth.  The theory was refined over the years and now is that the earth revolves around the sun.  The thing about theories, especially cosmological theories such as how the universe began, can’t be proven.  They can only be disproven.   If the theory fails to account for observations in the real world, the theory has to be discarded.

In college I had a chemistry professor who was fond of saying “atoms are what they are.  If the theory doesn’t explain them, we better get a new theory.”  What he meant was that, as scientific measurements and techniques get better, if what we are able to see isn’t explained by the theory, the theory of what an atom is will have to be revised or even discarded.

The Big Bang Theory is in that category.  The universe is what it is and if the theory doesn’t explain what we can observe, we better get a new theory.  Mankind (when I use the term “mankind” or “man”, I intend to include all of the human race, including women) has had many theories over the millennia about how the world and universe came to be.  Several have been rejected precisely because what has been observed isn’t explained, or predicted, by the current theory.  In fact, the Big Bang Theory is relatively new, having gained ascendancy over the Steady State Theory only in the last 50 years or so.

Before getting into the particulars of the Big Bang Theory we’ll examine some of the discarded theories and look at the development of science.  If we don’t know where we came from, it’s difficult to know where we’re going.

How it Began

I studied physics in college.  A bachelor’s degree doesn’t qualify you for much in the way of being a scientist, other than allowing you to apply to graduate school, but we did get an introduction to Einstein’s general theory of relativity.  Scientists, especially physicists, like to think they can find the reason for everything, including how the universe began.

Theologians, on the other hand, are satisfied with “In the beginning. . .God said ‘let there be light.’ And there was light.”  Physicists don’t like that because there is no mathematical explanation for God.  Since He can’t be explained by current theories, He can’t be part of the solution in their view.

Lately I’ve been wondering if science and religion can be reconciled.  Is there room for God in the current model of how the universe began?  What is the current thinking regarding how the universe got started?  Is there any more in scripture beyond “In the beginning” and if so, does it fit into the current model?  In short, can Genesis and General Relativity co-exist?

That will be the subject of my next several posts.