Certain types of relativity can be traced to the ancient Greeks, but an adequate study really begins with the classical or mechanical relativity of Sir Isaac Newton. He used the concept of inertia (an object at rest remains at rest or an object in motion remains in motion until an outside force acts upon it) to explain the universe as we find it.
To visualize Newton’s mechanical relativity, imagine you are standing on a platform. A vehicle with a window is traveling past. You can see a ball bouncing up and down on a table inside the vehicle. To a person inside the vehicle the bouncing ball appears to bounce straight up and down. To those standing on the platform and looking in the window, the ball is taking a zigzag path as it both bounces up and down and moves past you. The path the ball takes is relative to your point of view. Except for the path of the ball, everything else is the same to both those in the vehicle and those on the platform. Most important, time is the same to those on the platform and those in the vehicle. Albert Einstein called this absolute time, time which is same for everyone.
Albert Einstein first developed what we call special relativity. To use Einstein’s own illustration, imagine that you are in an idealized elevator that is forever falling to the earth. You are in perpetual free fall. You release a steel ball and a handkerchief at the same time. Because you, the ball, the handkerchief and the elevator are all falling at the same rate, you, the ball and the handkerchief seem to “float.” You are all part of what Albert Einstein calls “the same co-ordinate system (CS).” At this point you realize that you are falling and every part of your CS is in fact moving. Inertia is only apparent within your CS and time is another dimension which is also moving with your CS and is also relative. Today we would understand this illustration better if we replaced the elevator image with a space station orbiting the earth.
The last stage is the well-known theory of general relativity. You are now an observer outside of the elevator, watching someone inside it. You have a different CS. Time is different to you and to the man in the elevator. While he sees stationary objects, you see that everything is falling. There is no true inertia. Everything is always moving and this movement is relative to your CS, to your point of view.
Einstein found flaws in Newton’s mechanical theory. Newton taught that time was absolute. Einstein’s theory of Special Relativity, based on his discovery of the space-time continuum, taught that time is a dimension, like length width and height. Einstein thought at first that the universe was static. In 1917, fifteen years after developing his theory of Special Relativity, Einstein included what he called a Universal Constant to make formulas work in General Relativity. This was based on an assumption that the universe was static. Stars would move within the universe but the universe itself was a static force.
The theory that developed as a result of this conclusion taught that the universe will simply run out of energy and will cease expanding. Gravitational forces are not strong enough to cause contraction or collapse, but the universe will die a “heat death.” Everything will arrive at a uniform temperature, near absolute zero. There will be a uniformity of elemental composition. Everything will be dead and motionless.
Years later Einstein retracted his universal constant statement as the greatest mistake of his career, when the astronomer Hubble pointed out to him that stars have a Doppler Red Shift, proving that the universe is in motion. We know the universe is in motion because of the Doppler Effect, the shift to the infrared spectrum, visible in stars, indicating they are moving away from us. That may indicate that the universe is either expanding or contracting.
A common illustration of the Doppler Effect uses trains and a train station. When a train is approaching, passing, and going away, the changes in the sound of the whistle and the engine noises are an example of the Doppler Effect. In the case of light and more distant objects such as stars, the Doppler Effect will appear as a shift in the light spectrums. A star approaching us will have a shift toward the ultraviolet spectrum. For stars receding or going away, the shift will be toward the infrared spectrum.
The second theory is that the big bang is true and the universe is infinite. Gravitational forces are too weak to hold it together and it will expand for eternity. This is the current position of mainstream Physics and Astronomy today, and the one you must hold to if you expect to be published in academic circles. This is Stephen Hawking’s position.
The third possibility is that the universe will run out of the expansion force from the big bang. Gravitational force will pull it back together in what is sometimes called the Big Crunch, collapsing it back into a Black Hole. Some “mainstream” Physicists hold this view, but believe that it does not matter since we are still in the expansion stage and the Big Crunch is billions of years into the future. But the appearance of the Doppler Effect, that of distance increasing between Earth and other bodies, might actually be the universe collapsing. The Doppler red shift might mean we are pulling away from all other stars because we are in the lead, rushing toward a Black Hole and we are the closest to the event horizon.
The same Doppler effect is achieved whether you are at the station listening to a passing train’s whistle, or riding past in a train, listening to a whistle on a train sitting at the station. This is a minority position among physicists and implies that we are rapidly approaching the “Big Crunch,” the end of the universe as we know it, where we return to the original singularity.
These are the major positions postulated by Physics. Though there are many, many other positions and many, many variations on these positions, the important fact is that they are all religious beliefs which can never be proved. We can observe and measure the universe and some observations fit some models better than others, there is no scientific data on origins.
Sources include Einstein’s The Evolution of Physics and Stephen Hawking’s A Brief History of Time and The Universe In a Nutshell.
This work appears as an appendix in The Conflict of the Ages Part One: The Scientific History of Origins. 99 cents gets you the whole book.
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