In the late nineteen twenties it was discovered that distant galaxies appeared to be moving away from our own. Observations were under way of the spectra of distant galaxies and they all showed a consistent pattern, one which led to the deduction that the Universe itself was expanding. The result comes about because it is possible to split the light of distant galaxies into a spectrum or rainbow in the laboratory. Some specific wavelengths of light cannot get through the outer layers of gas surrounding a star. So instead of us seeing a smooth spectrum of colours, we see black lines on them at set wavelengths where that wavelength of light was absorbed by the outer layers of the star, hence, their name, black absorption lines. The problem was that this pattern of lines was not in the same position as those shown in the starlight from the majority of nearby galaxies. Instead, for distant galaxies not forming part of our local group, the same pattern was there, but the pattern showed a shift towards the red end of the spectrum. Since red has a longer wavelength than orange and orange a longer wavelength than yellow and so on through all the colours of the spectrum, it means that the wavelength of say orange light was stretched out to become red light and so on. We can observe this phenomenon, known as the Doppler effect, on the Earth with objects that are moving away from us.
You can most easily observe this phenomenon with sound when you are standing at the side of the road or racetrack. The hum of the engine has a higher pitch when it is coming towards you and a low pitch when it is moving away from you. Compressed sound waves as the car comes towards you have a higher pitch than stretched out sound waves as the car moves away. That is why we get that characteristic ee-ow sound as a car goes past. With light, the colour changes. Orange light stretched out turns red. Red light stretched out becomes infrared, which although now invisible to the eye, is detectable as heat. Ultra violet when stretched out becomes violet and then forms part of the visible spectrum. The conclusion is that distant galaxies are moving away and the name given to this effect is the redshift. What is more is that if we double the distance to a galaxy, then the redshift roughly doubles. This happens in whatever direction we care to look. The conclusion to be drawn from all this is that the space between the galaxies is getting bigger. The galaxies themselves are not getting any bigger. In fact, any system that is gravitationally bound does not take part in the expansion. Strictly speaking, it is the space between clusters of galaxies that is getting bigger. If this is the case then the whole Universe itself must be getting bigger or expanding. So, if you keep increasing the distance to the next galaxy and its speed of recession is greater, it follows that there must be a certain distance away where that region of space must appear to be moving away at the speed of light. Anything at a greater distance would in effect be exceeding the speed of light in relation to our viewpoint. Now, you may have heard that Einstein’s rules do not allow two objects to exceed the speed of light in relation to one another. However, when dealing with the expansion of the whole Universe, then this is permissible. We do not class it as relative motion.
Before the above discovery, the general opinion that prevailed was that the Universe was the same all over and in a steady state. The advocates of this picture or model, having been presented with the evidence and in an attempt to ridicule it, asked whether we were expected to believe that the Universe began from nowhere with some sort of “Big Bang”. The new model was christened.
Now, the one piece of evidence on its own, called the redshift, is not enough to put the weight of the scientific community behind it. One of the main tenants of science is that you should be able to make a prediction from what you know and then later verify the prediction. It had been predicted that if the Universe had begun with some sort of giant explosion or Big Bang, then there should be some remnant of this in the form of electromagnetic radiation, which although now very feeble, should be detectable. The idea is, that if the Universe had begun in a very dense and hot state, then the photons of energy, which constitute electromagnetic radiation, would not be able to travel very far in the early Universe without hitting some matter such as a proton or an electron. At this early stage, the temperature of the Universe would have been so high that it would have been in what we call a plasma state. It would be too hot for the electrons to be bound to the protons to form atoms. After about a million years of expansion the temperature would have cooled enough for the electrons to collapse towards the protons and hydrogen atoms would have formed. This then created an immense amount of space for the first time and the electromagnetic radiation was then free to move through this space without hindrance. Astronomers refer to this epoch as the moment of decoupling. That is, the separation of matter and energy. As the Universe continues to expand, these photons of energy have had their wavelengths stretched and the radiation has cooled. The prediction was that it should have cooled to a very low temperature of around ten degrees Kelvin. That is ten degrees above absolute zero or the coldest temperature theoretically possible. For those who prefer Celsius temperature this is around –263 degrees Celsius.
Now in the nineteen sixties at Bell Laboratories in New York, two scientists discovered a strange hiss of electromagnetic radiation being apparently received in a radio antenna they were using. Other explanations such as pigeon droppings in the antenna were discounted. The radiation detected had its peak or strongest part of its spread in the microwave region of the spectrum and turned out to be the type of radiation that would be emitted by a body at a temperature of around 2.7 degrees above absolute zero or – 270.3 degrees Celsius. Although slightly off the predicted value, this was taken to be the left over radiation from the Big Bang. The sky was examined in all directions and within experimental error the radiation was coming from all directions at the same temperature. The word scientists use for this is isotropic, meaning the same in every direction. Since this radiation was there all over, in the background, it became known as the background radiation or microwave background radiation as most of the radiation was in the microwave region of the electromagnetic spectrum. The Big Bang model of the Universe was established.
The redshift and the background radiation are the main pillars of support upon which the Big Bang model of the Universe is founded and there are other minor struts of support from other areas. The amount of Helium in the Universe is one of them. Helium makes up about 25% of the Universe. In the centre of stars, hydrogen fuses to form helium. In the process, this releases energy. Theory shows that in the time interval since the Big Bang to the present day, there is not enough time for all the helium present to have been produced in stars. It has been shown however, that the amount of fusing necessary to produce the helium abundance seen, could well have taken place during the very early stages of the Big Bang itself. Another strut of support is that galaxies appear to be less developed in the farthest reaches of the Universe.
A consequence of the big bang model is that the Universe itself must have had a beginning. By knowing the rate of expansion, it is possible to run this back in time, with the result that the initial explosion must have taken place somewhere between ten to fifteen billion years ago. Usually anything that has a beginning must have an end. How the Universe will end, if that is the case, is open to speculation. The Universe may have enough mass in it to be able to slow down and halt the expansion by its own gravitational attraction. The Universe may then collapse in on itself over a very long period. Then the whole of space and time would disappear. This has been nicknamed the “Big Crunch” and is also called a “Closed Universe”. Who knows what would happen next? There could just be nothing or could there be another Big Bang to reinvent the Universe?
If there is not enough mass to halt the expansion, then the Universe expands forever. The stars in the galaxies eventually burn out and the Universe goes colder and colder and runs down and dies. This is called the “Open Universe”. A compromise, where the expansion just gets slower and slower but never quite stops is called the “Flat Universe”. Yet the fate is still the same as the Open Universe. The result would be another cold death.
You may notice that the word model has been used here rather than a theory. Theories, although themselves not proven to be correct, tend to carry more weight than models. The Big Bang has had its own problems and there are still loose ends. Therefore, term model is more appropriate than theory. Instead of simple known physical laws explaining everything, the model has had to be tweaked or had bits bolted on to it to enable it to fit the facts. One apparent anomaly, is that on a large-scale, parts of the Universe look as though they have patterns or structure. To have this, they must have had time to pass information between adjacent sections. Under the conventional model, there is no time since the beginning of the Universe for there to have been communication between the two regions. It was then proposed that maybe the Universe underwent an extremely fast rate of expansion or inflation in its very early stage, so fast that space was expanding faster than the speed that light could cross it. The idea is, that now seemingly unconnected regions of the Universe could have been connected during this rapid inflationary period. We are only talking about a fraction of a second after the beginning of time and space. Then another problem made the headlines a few years ago. This was that many old stars appeared to be older than the age of the Universe itself. This has largely died away after further observations of the rate of expansion have made the Universe somewhat older. Recently, another problem has arisen which is not as easily explainable. Astronomers in the past have largely relied on standard candles called Cepheid variables to help them locate the distance to distant galaxies. These stars pulsate in brightness over a period of days. There is a direct relation between the period of these pulsations and the star's intrinsic or absolute luminosity. Therefore, if you know how bright they should be, from the time between pulsations, then you can use them to estimate the distance to the distant galaxy in which they reside. This has given fairly good results in our own region of the Universe in that doubling the distance to a galaxy roughly doubles the amount of redshift. It was thought that if you could look even further out into the distant Universe then the rate of expansion out there would be greater than the rate of expansion in our own locality. This is because as you look into the distant Universe you are also looking back in time. Therefore, if the gravitational field due to the matter in the Universe slowed down the expansion, then our own region being older should be showing a slower rate of expansion than in distant regions. A new standard candle has made observations of very distant regions possible. There is a particular type of supernova, which always has the same intrinsic luminosity. Although not very frequent, they are frequent enough to be able to build up a picture. The only problem is that the unexpected has happened. The Universe appears to be expanding faster in our own region than in the distant Universe. Therefore, the Universe appears to be expanding faster over time rather than slowing down. Now there are all sorts of explanations being banded about as to what may cause this. A repulsive force first envisioned and then abandoned by Einstein is one suggestion. Another suggestion is perhaps there is some sort of esoteric energy that is causing the Universe to accelerate. “Dark energy” is a new phrase to enter our vocabulary. This may be causing the acceleration. It is difficult to understand what is going on within the big bang model.
Another problem, which is simpler to understand yet difficult to envisage, is just what things were like at the time of the Big Bang. Just after the Big Bang we have to imagine all time and space being wrapped up in a space no bigger than a grapefruit. Before that, there was no time and space. There was no inside and no outside. There was nothing, not even space or time itself.
I have half swallowed the expansion and the big bang model of the Universe, but something about it still gets stuck in my throat.
To return to the main theme of this book we appear to have a number of paradoxes. If God is the Universe, then God himself would have been created. He will also have an end. What happens in between is largely inconsequential. It does not seem right does it?
The problem is, that we have a man made model based on observations. It does not mean that it is proven. We are reminded of the apparent flat Earth, the apparent movement of the Sun and stars around the Earth, our apparent central and special place in such a vast Universe. Sometimes things turn out in the end to have a very different explanation. The problem with the Big Bang model is that it has become so firmly entrenched in science that you are not likely to read anything which disagrees with it. Every program you will see on television always refers to the Big Bang and the creation of the Universe. Suffice it to say, without writing a book within a book that there are alternatives that do exist, providing that you know where to look. Alternative cosmological models are something upon which I have given a number of talks on at local astronomical societies. If the expansion turned out to be an illusion and the microwave, background something else then the Universe would not be expanding. The alternative to that would mean that the Universe was dynamically balanced and eternal. There would be no beginnings and no ends. We would live in a continuous self-propagating Universe where recycling and continuous creation took place. In such a Universe, black holes would play an important part in the constant recycling of the Universe’s components and would not be the so-called “dead end” where all the laws of physics break down. It would just be that we do not yet have a grip on how they work yet and the true role they play in an eternal Universe. Something tells me therefore, that we have a lot more to find out about the real purpose of black holes. Rather than saying that the known laws of physics break down, it may be better to just say that we do not know what the hell is going on yet.
The extracts which open this chapter appear to indicate that God is eternal, everlasting and without change. If our ideas are to hold together, then this must apply to the large scale structure of the Universe.
In the appendices there is an alternative model given for those who have an open mind and can conceive of the fact that the Universe may well be in an eternal and balanced state without the expansion. It is separate for two reasons. Firstly, it is only suitable for anyone who may have gone beyond GCSE physics in their studies and secondly it would disrupt the main theme or continuity of our story. The upshot of it all is, that there is an outside chance that the Universe may well be an eternal structure which, continually regenerates itself due to the action of black holes and that on a large scale the Universe does not change.
For further information try entering the following words in different combinations in your search engine: cosmology, universe, big bang, illusion, alternative, supernova and plasma. Also try, rufus young steady state galaxy.