reply to post by antonia
No, the universe is a closed system. It has borders and is curved.
Uh-huh. I see. Been to the borders, have you? Are you the cartographer who has mapped out those borders and its curve for all of us to see? Would
you mind showing us this map of the universe, with its clearly defined borders and how it curves?
All expansion occurs in the fourth dimension.
Okay, okay, okay, I am not sure where you were taught physics and astronomy but let's get some facts straight here. The current theory regarding
the nature of the universe is that it is an expanding universe. It is important, when discussing this theory of expanding universe, that we
understand how such a hypothesis was formulated.
Prior to the formulation, in cosmology, and astronomy, the physics being used led observers to observe a paradox. The paradox has truly existed for
thousands of years as the ancient Greeks noted that in regards to the universe, it is either infinite or finite, both of which come with problems,
thus the paradox. However, after the advent of telescopic observation, by the time of early 19th century, an astronomer by the name of Heinrich
Olbers began advocating a finite universe paradigm. His assumptions were based upon our own perceptions, or more accurately his perceptions. Olbers
argued that if the universe were infinite, and that infinite universe filled with stars, then our own line of sight would eventually fall upon a star,
no matter where we looked up in the nighttime sky. It must be remembered, of course, that regardless of the size of any star, the brightness of that
star remains constant. Based upon Olbers assumptions, then if the universe were infinite, our nighttime sky would be bright with the brightness of
all the stars that should be there, but obviously the nighttime sky is not bright, and there are dark areas of the night, so Olbers posited that the
universe must be finite.
The paradox of this hypothesis takes us back to Newtonian physics and that understanding of gravity. What Newton had discovered was that gravity is
always attractive. In this universe of oh-so pretty, pretty objects, every object attracts every other other object. Under this understanding, then
the universe should, at some point, collapse in on itself. Since this mathematical (based upon physics) equation had obviously not borne itself out
yet, astronomer's and physicist's alike were presented with a paradox.
Now, enter Einstein. Einstein's own perception of the universe was that it was static, but in developing his own theory of gravity, under the
General Theory of Relativity, it seemed as if he ran into the same problem Newton was having with the math and its paradox. Einsteins equations were
telling him that the universe should be either expanding or collapsing. To deal with this problem, Einstein developed a solution we now know as the
Cosmological Constant. This cosmological constant essentially canceled out the effects of gravity on a large scale, allowing Einstein to maintain his
own perception of a static universe.
Later, after the discovery of an expanding universe by Edwin Hubble, Einstein would call his cosmological constant "one of my greatest blunders",
but at this point in this brief history of how we've come to understand the universe, it should be noted that these understandings were largely
informed by the perceptions of the experimenter or researcher. Olbers understanding of a finite universe was informed by his own perceptions of the
universe. Newton's as well as Einsteins understandings of gravity, and the universe were informed by their own perceptions, and to be sure, when it
came to Einstein, when the math went against his own informed perception, he played fast and loose with reality to cram the math in a way that would
bear out his perception.
Getting back to the expanding universe theory, as telescopic technology advanced, astronomer's, such as Vesto Slipher, discovered what we now call a
redshift, which helped to better understand the plethora of faint lights astronomer's were now seeing with the advancement of telescopes. When these
distant faint lights were posited to be distant galaxies, while physicists and mathematicians were simultaneously working with Einstein's theory of
gravity, equations were discovered that might help explain the idea of an expanding universe, where the redshift is the product of light shining from
distant objects as that light travels through an expanding universe. As an object becomes increasingly distant, the redshift will increase, or so say
those working with Einstein's theory of gravity, and understanding that astronomer's have declared the distant lights as distant galaxies, or if you