On Jun 17, 3:59 am, "
microm2...@hotmail.com" <
microm2...@hotmail.com>
wrote:
> On Jun 16, 12:56 pm, Shawn Wilson <
ikonoql...@gmail.com> wrote:
>
> > I believe it involved All You Can Eat Burrito Night, but the details
> > are sketchy...
>
> The atheists would say that nothing caused the Big Bang.
"What caused the Big Bang?" is what in physics we call a boundary
value problem. Basically, the problem is that time is measured in
relativity using the constant speed of light: if you measure out one
light year then the time it takes for light to travel that distance is
one year, and so on. And light is a form of electromagnetic radiation
which means that if you want to produce light you need to have postive
and/or negative electric charges and you need to have them
accelerate. The upshot is that there is no way to measure time in an
empty universe so the Big Bang is eesentially the beginning of time.
The question becomes then what happens when we go back farther and
farther in time.
Actually, Steven Hawking addressed this issue over twenty years ago in
A Brief History of Time. The first thing to realize is that entropy
increases with time. Hawking went further to point out that the human
brain is a biological machine that generates heat and increases the
entropy of the universe every time it stores new memories. Of course
we define "the past" as what we remember and "the future" as what we
don't remember and therefore assume hasn't happened yet.
Now what happens then when we go back further in time? The entropy of
the universe decreases. Thing is, what does the universe look like
when the universe is at zero entropy?
Zero entropy is achieved when there is no motion. If the universe has
zero entropy then nothing is happening. This makes sense: you go back
further and further in time until you get to a point in time when
nothing is happening. Then things start happening. This was the Big
Bang.
In statistical physics, the concept of entropy is associated with the
concept of randomness. For example, an open bottle of perfume has
more entropy than a closed bottle because the open bottle allows
perfume to escape the bottle and spread out all over the room. Note
that the fact that entropy increases explains why you always see
perfume escaping from the bottle and not collecting in a bottle. (You
can also view the path of each molecule of perfume as a stocastic
process and realize that the probability of any individual molecule of
perfume returning to the bottle is extremely low.)
The big bang then is like the proverbial genie that you can't put back
into the bottle. Physicists used to wonder if there were enough
matter in the universe to cause gravity to overcome electrostatic
forces and cause the universe to collapse into a "big crunch". Of
course, if that were to happen it would look a lot like time running
backwards.
In a Brief History of Time, Hawking then lost most readers when he
started talking about "imaginary time" being a "forth dimension in
space". Basically, Hawking here was taking nomenclature from general
relativity. General relativity is, as the name suggests, an extension
of special relativity. In special relativity, different frames of
reference were said to be related through "rotations in space-time"
where imaginary time is the fourth dimension in space. In general
relativity, gravitation was modeled as a distortion of space-time.
Hawking's insight was to see the entire universe as an object is space
time and as the boundary in time as a physical boundary in fourth
dimensional space. He then mentally rotated this object and asked if
there was still a well defined beginning. The answer of course is
that there isn't: just as a three-dimensional object does not have a
well defined beginning and end, so would a four dimensional object not
have a beginning or an end.
To paraphrase Hawking then, if the universe has no well defined
beginning of end then why do we need to talk about a creator? "What
if the universe just is?" he said. "What then is the need for a
creator?"
Martin