Saturday, October 26, 2013

Modern Cosmology

 I was reading this morning the comedy of modern cosmology.  One positive note; of late these cosmologists seem to be worming up to the idea “Who coverest thyself with light as with a garment: who stretchest out the heavens like a curtain:” – Psalm 104: 2  You see some of them think the Universe has a diameter of 156 billion light years while all the lemmings agree the Universe is about 13.7 billion light years old.  Read for yourself from CNN.com

“"All the distance covered by the light in the early universe gets increased by the expansion of the universe," explains Neil Cornish, an astrophysicist at Montana State University. "Think of it like compound interest."

Need a visual? Imagine the universe just a million years after it was born, Cornish suggests. A batch of light travels for a year, covering one light-year. "At that time, the universe was about 1,000 times smaller than it is today," he said. "Thus, that one light-year has now stretched to become 1,000 light-years."

All the pieces add up to 78 billion-light-years. The light has not traveled that far, but "the starting point of a photon reaching us today after traveling for 13.7 billion years is now 78 billion light-years away," Cornish said. That would be the radius of the universe, and twice that -- 156 billion light-years -- is the diameter. That's based on a view going 90 percent of the way back in time, so it might be slightly larger.”

If you extrapolate this idea just a bit more, then a 6,000 year old Universe is not hard to see.  I am reminded of a problem I gave my high school students when I was a math teacher.

Just for fun let’s say that the 13.7 billion year age is an accurate coordinate time age for the Universe and that the 78 billion light year radius is equally as good and that it all started at the big bang.  What would the proper time number look like?  Well, the velocity of the expansion after the big bang is generally agreed to be preposterous or insane or some other such adjective by these folks ( LUDICROUS SPEED).   Ok, maybe not ludicrous speed.  Let’s try an average rate of expansion of 0.9999999999999c where c is the speed of light.  According to the accepted formula, ΔƮ = ΔT*SQRT(1 – v^2/c^2), for proper time ΔƮ, then due to the observable phenomenon of time dilation proper time would be about 6,128 years.  In relativity, proper time is the elapsed time between two events as measured by a clock that passes through both events.

In other words, if we would have lived through the events of the supposed big bang as they unfolded the current physics tells us that it would have taken no more than a few thousand years (proper time) for the Universe as we know it to have formed.

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