Beauty in the Equations
Today's image is much more pleasant. History shows that our achievements last longer than the obstacles. That is reason to spend years working on something that may not be recognised in this lifetime. I hope you all enjoy the graphics.
The "Big Bang" can be drawn as a point. Cosmologists agree that the baby Universe had a finite volume and therefore a finite mass M. All points of this Universe were very close to one another. Our separation from the Big Bang is a matter of Time, not Space. That interval is simply age t of the Universe. Astronomers have estimated that age at about 14 billion years.
The light cone represents the local conditions of Special Relativity. Our mass, even the mass of our galaxy, is negligible compared to mass M of the Universe. We are within the light cone of that enormous mass, and its gravity is affecting us. Fortunately there was only one Big Bang to pull us back. As Newton showed, the gravitational force from a spherical mass distribution is the same as if all that mass were concentrated in a point.
Einstein theorised that this Universe is of spherical shape. Our three dimensions x, y and z are now confined to a circle. Any direction that we can travel in Space keeps us within that circle. The Universe might appear infinite and flat to our experience, but can still be curved in the fourth dimension.
In this spherical Universe, the combined gravitational attraction would be the same as if everything was in a point. There is no centre in Space, for every bit resembles every other bit. There is a centre in the Time dimension, which we call a "Big Bang." As time passes, our Universe expands away from the Big Bang.
Newton's Law of Gravitation insists that mass affects us at a distance. It is meaningless to express this attraction over Time, so we must add the conversion factor c. Here we can expand on one principle of Special Relativity. Since Space and Time are one phenomenon related by c:
Scale R of the Universe is its age t multiplied by c.
This astonishingly simple relation tells why we live in a growing Universe. As time t increases, scale R expands. Most laws of physics are time-symnetrical; they do not favour any direction forward or backward in Time. Expansion does not share this symnetry, it is called an Arrow of Time.
At a distant beginning time of zero, the Universe would have had zero dimension. Everything that we know resembled a single point. Since that time our Universe has been expanding. It can't expand at the same rate c continuously, for gravity slows it down. Conversion factor c must be further related to t. This leads to an astonishing but testable prediction.