The Big Bust

If you were to ask a recognized astronomer to describe the nature of the observable universe today, he or she would say that it is like a giant expanding balloon of intergalactic space, consisting of planets, stars and galaxies, that is roughly 100 billion light years across, and about 14 billion years old.

The prevailing cosmological model that is accepted by most scientists, is that all the matter and energy that now fills the universe was flung out from a primordial explosion of quite unimaginable fury, and that everything we see in the sky today is the consequence of that original explosion. This theory is referred to by astronomers as the “Big Bang”.

But according to a small but influential group of scientists, this theory is not only outdated, it is plumb wrong. And it is their contention that the carefully structured theory of the “Big Bang” has now become the “Big Bust”.

And if that were not shocking enough, they go on to say that the prevailing ideas about space as well as the nature of the planets, stars and galaxies are also wrong, for reasons we will explore in the following instalments.

The edifice that is modern Cosmology stands on the legs – although sceptics might say that it rests on the crutches – of two technological marvels. The first is known by almost everybody. It is the telescope. The second is known by relatively few outside the world of astronomy, yet it’s role in determining science’s view of the universe is critical. It is the spectroscope.

The first rudimentary telescope was constructed in the year 1609 by the Italian astronomer Galileo Galilei, who like his compatriot Dante Alighieri came to be known by his first name only. The telescope was an invention that almost cost Galileo his life.

The late Middle Ages were a dangerous time to be alive in Europe, and men and women who espoused new ideas did so under the threat of agonizing death. The Catholic Church was enthroned as the supreme guardian of thought. Its lieutenants were swift to brand as heretics all those who would sully the infallible word of God.

A firestorm of heretical tribunals swept across Western Europe in an effort to stay the stirrings of people’s minds. Anyone found guilty of heresy would pay a penalty in this world, by burning at the stake, that matched his or her inevitable fate in the next, that of being cast into eternal hell-fire.

At such a time it is hard for us to imagine the courage it must have taken for Galileo to announce in public, the idea that the earth travelled around the sun. In observing the heavens with the magical eye of his telescope, Galileo discovered that the moon had a cratered surface, unlike the smooth, flat surface taught by Aristotle, and that it shone by the reflected light of the sun, and not by virtue of an inner source of light.

He also showed that the planets Venus and Mercury demonstrated phases, just as was required by the Copernican system. Through his telescopic view, Galileo was able to see the four major moons of Jupiter rotating around the Jovian planet, just as the other planets were predicted to revolve around the sun.

Supported by the evidence of his own visual sightings, Galileo became convinced of the truth of the Copernican thesis, and began publicly to expound his views. This thoroughly alarmed the Church in Rome, and in 1616 Galileo was ordered to cease his support for what had come to be known as the “Copernican system”.

Galileo recanted and agreed to remain silent.  But he used this period of enforced silence to write a book in which he debated the motions of the heavens from two conflicting points of view – that of Ptolemy, and that of Copernicus. In his final verdict to this dialogue, however, Galileo effectively demolished the old Ptolemaic system of astronomy.

Although he had sought the precaution of getting prior clearance from the authorities in Rome, the publication of his book brought an immediate summons to appear before the Inquisition on a charge of heresy. Galileo had done more than merely challenge a theory of celestial motion, for his book was a frontal attack on the fundamental basis of Catholic theology.

Since theology fixed man as the centre of divine concern, it was clear to the Church that the universe was created to serve the needs of man. The earth was at the centre of this divinely ordained universe, and all of creation was thus made for man’s service.

Man derived his knowledge of the universe from two sources – from human reason and divine revelation. The highest attainments of the human mind were considered by the Church to have been recorded in the works of Aristotle, while the Holy Scriptures contained revelations on all other things which could not directly be understood by the human mind.

Through a synthesis of these two paths, everything could ultimately be known. If it were now possible to prove that it was the earth that moved, rather than the stars around it, man’s very position at the centre of God’s plan would be called into question. Could there be any greater heresy, or one more worthy of the flame?

Galileo argued his own defence by resorting to his telescope. He invited his accusers to look through it and see for themselves the motions of the moons of Jupiter. The cardinals were incensed!

“We will not look through your telescope”, they cried, “because we already know how the universe is ordered. Aristotle, scripture and tradition have pointed the way for centuries. If your telescope were to show us anything different, it would be an instrument of the Devil.”

Galileo was ordered to make a public recantation. Kneeling before them, he was forced to read a statement confessing that he was ready to “curse, abjure and detest” the theory that the earth moved round the sun. Legend has it that at the end of this confession Galileo was heard to mutter under his breath, “But it does move”.

Galileo was lucky. He was spared the rack and the fire. But his fate was to be cut off from the world at his villa at Arcetri in Italy, where visitors were forbidden. In the latter years of his life, his sense of isolation was further deepened when he became completely blind. When he died in 1642 the Pope forbade the erection of any monument on his tomb that would honour his name.

Over the span of nearly four hundred years since Galileo’s death, scientists have refined his original telescope to a degree that would have astonished him. Not only have optical telescopes developed in sophistication and size, but modern telescopes now include radio telescopes, as well as others classified by the wavelengths of light they detect – such as X-rays, ultraviolet and infrared telescopes.

And of course all of earth-based optical telescopes are dwarfed by the capabilities of the Hubble space telescope, which was first lifted into low earth orbit outside the distortion of earth’s atmosphere in 1990, and still continues to send back extremely high-resolution images with almost no background light.

It was not until 1666 that Sir Isaac Newton, who has since come to be regarded as one of the greatest scientists of all time, discovered that sunlight, or white light, was actually a combination of all the colours of the rainbow, and that by shining sunlight through a prism, all of these different colours could be displayed on a screen in the form of a spectrum.

Early in the nineteenth century, a British physicist named William Wollaston noticed an odd feature about this solar spectrum. Its display of multicoloured bands was characterized by a series of dark, vertical lines, as shown in the simplified diagram below.

Then in 1814 a German optician by the name of Joseph Fraunhofer invented a device that was able to disperse, or separate, white light from a star into a much wider spectrum of colours than could be seen through a normal prism. This device came to be known as a spectroscope, or spectrometer.

The invention of the spectroscope, which made it possible to analyse the composition of any spectrum of light, and to determine the characteristics of its source, provided as revolutionary a tool for astronomers as Galileo’s telescope had been initially. For it was now possible to examine the light of the stars, and to determine their chemical composition.

Several years later, Fraunhofer made a spectrograph of sunlight, and counted 574 dark lines appearing against the bright background of the solar spectrum. These dark lines appearing in the spectrum are still referred to as Fraunhofer lines today, as a tribute to his pioneering work in the field of optics.

The cause of these lines remained a mystery until a German physicist named Gustav Kirchhoff announced that they represented an absorption of the specific wavelengths of light emitted by the sun.

He explained that the lines in the solar spectrum were due to certain wavelengths of light that were being absorbed by the gaseous atmosphere of the sun. Because these wavelengths were absorbed, they appeared as gaps in the spectrum which revealed themselves to the observer as dark, vertical lines.

Kirchhoff showed that every element in nature had a distinct and specific signature of lines present in its spectrum. So, for example, if white light was passed through a gas before being shone through a prism onto a screen, the gas would absorb certain wavelengths of that light. The resulting spectrum would show certain black lines appearing in specific places.

It was found that it was possible to identify a gas by its signature of lines. Furthermore, if a gas or any other element was heated and caused to emit light, it would emit only those wavelengths which characterized that particular element or gas.

So instead of a continuous spectrum marked by dark, vertical lines, there would now be certain narrow, vertical slits of light, and these would appear at precisely those places where the dark lines had been in the continuous spectrum.

Yet another crucial breakthrough in the understanding of the heavens derived from a principle that had earlier been explained by the Austrian physicist Christian Doppler. It was known that a moving source of sound changed its pitch as it passed a stationary observer.

As Doppler explained, whenever a source of sound was moving in relation to an observer, a change of frequency occurred. This frequency increased when the source approached the observer, and decreased when they moved apart. This principle came to be known as the Doppler effect.

Because light was also known to be a phenomenon of waves, it was assumed that they travelled through space in a  manner similar to sound. The waves of light appeared to increase in frequency when a source of light moved towards an observer, and to decrease in frequency when it moved away. While this effect was not noticeable at low speeds, it became very pronounced when a source of light was moving at a speed that approached the speed of light.

When a source of light approached an observer at high speed, the waves of light shifted in frequency towards the right, or blue end of the spectrum. But if the source was receding at high speed, the waves of light moved towards the left, or red side of the visible spectrum, as shown in the following diagram:

As distant galaxies recede from earth, their light shifts towards the red end of the visible spectrum.  The amount of shift shows how fast different galaxies are receding, and how far they are from earth.

In 1912, Vesto Slipher, an astronomer at the Lowell observatory in the United States, made a strange discovery. He found that the spectral lines of a nebula he had been observing were not in their customary positions on the spectrum. Mysteriously, they had shifted towards the red end of the spectrum.

What mystified Slipher was the extent of this red shift. If this shift was to be explained as the motion of the nebula away from the earth, then it would have to be traveling at a speed of about one thousand miles (1600 kilometres) a second. This was far in excess of the speeds which had been calculated for other stars in the firmament.

It was Edwin Hubble, a former Rhodes scholar and astronomer at the Mount Wilson observatory in California, who obtained conclusive evidence that these light sources were unlike the nearby stars. They were in fact conglomerations of stars which lay beyond the galaxy to which the earth belonged.

These island universes roamed the vast reaches of space, and just like our own Milky Way galaxy, were composed of myriads of stars.  In 1929, Hubble published his discovery that the velocity of these galaxies increased with distance. He was able to show a simple relationship between the distance of a galaxy and the shift in its spectral lines of light.

The farther out each galaxy was from earth, the faster it was travelling. However, Hubble was surprised to find that all the other galaxies were moving away from the earth. He concluded that the entire universe was expanding, and that everything was moving farther away from everything else.

The British astronomer Sir Arthur Eddington, explained Hubble’s discoveries by likening the universe to a rubber balloon. The galaxies, he pointed out, could then be pictured as being embedded in the surface of this balloon. As it was inflated, so these celestial objects would move farther and farther apart, as a result of the balloon becoming larger.

They would move out farther from each other, but at the same time all galaxies would move farther from the centre of the balloon. As astronomer and author Carl Sagan of Cornell University later wrote:

“This red shift, observed in the spectral lines of distant galaxies and interpreted as a Doppler effect, is the key to cosmology.”

The reason why is that it not only provided the key to understanding the motions of the cosmic travellers, but it led directly to the conclusion that all the matter in the universe could be traced back to a single point of origin. Although the speed of light seems instantaneous to us on earth, its speed is known to be of the order of 186,000 miles (300,000 kilometres) per second.

Because the galaxies which move in the outer reaches of the universe are at almost unimaginably large distances from the earth, the light which leaves each glowing galaxy in the depths of space can take many millions of years to reach us.

And when this light is observed by our astronomers, it does not record the state of the galaxy as it is now, but the state in which the light began its journey. For all we know, it is possible that many visible suns may no longer exist in space and time. The news of their destruction has yet to reach us. And in the case of the most distant objects, the light from these sources has taken many billions of years to reach the earth.

So as astronomers gaze into the farthest reaches of space, they actually peer farther back in time, for the light they see reveals the state of times long past, as far ago as the time it takes to reach us.

The most distant objects seen by astronomers in the heavens are strange cosmic creatures known as “quasars”, derived from their more technical description as “quasi stellar radio sources”.

Although these objects look like stars, they generate quite enormous amounts of energy compared to regular stars. When light from these quasars is examined through a spectrometer, it shows them to be travelling at speeds of up to nine-tenths of the speed of light, which is considered to be the ultimate limit of speed in the universe.

Examinations of their red shifts have placed them at the very outermost regions of the known universe. The latest computations place them some fourteen billion light years from earth.

It is through the interpretation of the red shift as a Doppler effect, as Sagan has indicated, that provides astronomers today with their current explanation of cosmology. It not only gives the vital clue to the motions of nebulae, stars and galaxies, but it also provides the key to unlocking the age of our universe.

As a result of these two factors, if the present motions of observed light sources are reversed back into the past, all the known matter in the universe would have been combined into a single source about fourteen billion years ago.

Based on this premise, scientists have theorised that our universe began with an event that has come to be known as the “Big Bang”.

So according to accepted scientific theory, our universe stands testimony to the results of that primordial fireball. Astronomers also claim that their radio telescopes have even heard the echoes of that original bang, for the weak residue of cosmic radiation remaining from that original explosion has been detected emanating from all parts of our surrounding sky.

All seemed well in the ordered world of Cosmology until an American astronomer by the name of Halton Arp published a book in 1966. The title of the book was the Atlas of Peculiar Galaxies.

Based on the findings of this book, allied to his later research, Arp not only challenged accepted theory, but went on to list his reasons why he believed that the entire theory of the “Big Bang” was fundamentally wrong.

By a strange twist of fate, Hubble’s law, which formed the foundation of the established theory of Cosmology, was now being challenged by the very man who had once served as his assistant, while Edwin Hubble was conducting his research at Mount Wilson Observatory in California.

We may suppose that established scientists of the time would have welcomed this new insight into the true nature of our heavens, and accorded Arp the opportunity to conduct further research into his novel ideas.

But sadly, despite the many centuries that had passed since Galileo had been persecuted for his bold ideas, Arp’s superiors reacted with the same prejudice and scorn displayed by those early cardinals of the Catholic church.

There was no reason to investigate his ideas, they agreed, because they already knew how the universe was ordered. Galileo, Newton, Doppler and Hubble had pointed the way for centuries. If the results of Arp’s research were to show them anything different, they would have to be cast out – just as if they were the work of the Devil.

Halton Arp was shunned by his colleagues, and denied the use of the Palomar Observatory to further his investigation. Despite being a Fellow of the Carnegie Institution of Washington, as well as having been a staff member at Palomar for 29 years, he lost his job and was forced to leave America to practice his profession elsewhere, as we shall see in the next instalment.

 

This entry was posted on Friday, April 10th, 2020 at 2:47 pm and is filed under Signs in the Sky. You can follow any responses to this entry through the RSS 2.0 feed. Comments and pings are closed.