science sense and common sense, was Intelligent Design Invading Liberal Classrooms

Tarquin wrote:
There is indeed a "correct" scientific position. You use common sense
until you KNOW differently. That if fact is the most fundamental precept
of all science.

No, it is not. The most fundamental precept of science is that
nature exhibits regularities, which are revealed through observation
and experiment, and which we identify through induction and analysis.
If that weren't so, there would be no point in doing science, whereas
there still is point to doing science even if it doesn't coincide with
common sense. There is a *scientific* sense which is applied in
induction, but it is very often not common at all, and especially when
applied to conditions which (like the Big Bang) are explicitly known
*not* to be common.

Where do you get the notion that the big bang occured "outside" the
universe? Or that the laws of thermodynamics didn't apply before it?
What is the evidence for that? I've never seen any.

You've subtly changed what Chris said. He did not say that the laws
of thermodynamics do not apply "before" the Big Bang (whatever that
might mean); he said that there is no evidence that they exist outside
of the Big Bang. That is perfectly true--there is no such evidence.

What's more, the laws of thermodynamics are not the absolutes you seem
to suggest they are. For one thing, energy is not even well-defined
for strongly curved pieces of spacetime, so that the first law of
thermodynamics cannot be exactly applied except for closed systems in
asymptotically flat pieces of spacetime. There's no such thing, though
very good approximations exist in laboratories. But certainly the
initial conditions at the Big Bang are too curved to expect energy to
behave the way "common sense" predicts it to.

There are ways around this, using what are called pseudo-tensors, but as
I understand it, their use is somewhat controversial because they don't
transform like tensors (as their name suggests), which violates one of
the principles of general relativity--that the laws of physics are the
same in all reference frames. They *almost* transform like tensors...
but not quite. So it is far from certain that we can count on the
conservation of energy at the Big Bang; in fact, it seems almost
certain that we cannot.

The second law of thermodynamics is also not an absolute. On a large
scale, it speaks of the spontaneous behavior of closed systems, but on
a sufficiently small scale, it becomes clear that it only speaks of
what is overwhelmingly likely to happen, and that "likely" becomes
every more underwhelming as the size of the system diminishes. At
some point, in small enough systems, one can't really define temperature
well enough to apply the second law, either.

What this means is that not only do we have no evidence that the laws
of thermodynamics held outside the Big Bang (that is, so that they are
applicable to whatever conditions precipitated the Big Bang), but we
even have good reason to think that they don't have any significance
under those conditions.

I find it interesting that you have no trouble speaking of "before"
the Big Bang, but "outside" the Big Bang troubles you. It suggests to
me that you haven't really grokked the Big Bang.

It produces absurd results such as found in quantum mechanics that lead
to even further absurd requirements like a new dimension for every day of
the week. If it wags its tail and barks like a dog it probably IS absurd
even if it does cock its leg from time to time.

You cheapen the work of theoretical physicists simply because you do
not understand it. The extra dimensions are postulated not out of
sheer whim, but because of the requirement that, again, the laws of
physics look the same in all reference frames. In order to achieve
this, spacetime must exhibit certain symmetries, so that things transform
the way they're supposed to between those reference frames.

Most spacetime geometries do not satisfy these constraints. Those that
do may look strange to our three-dimensional eyes, but they are under
no mandate to look natural to us. What they *are* required to do is be
consistent with observation and experiment. We're not able to conduct
some of these experiments yet, because they require energies that are
not under our control, but someday, perhaps, they will be.

There is no evidence that there is an "outside" the universe so why on
earth do you start out assuming there is?

Chris does not assume that there is an outside. It was you who
suggested that the laws of thermodynamics (again, not applicable under
those conditions, but for the sake of argument) required that the
energy for the Big Bang be there all along, and then suddenly, for
some reason, the Big Bang happened. By definition, any precondition
for the Big Bang (and by precondition, I mean in the mathematical
sense, without any temporal significance) is outside the universe,
which the Big Bang created.

And you still haven't answered the question of how all this energy
compressed into such a tiny volume in your conception remains stable
for all eternity until it suddenly decides to expand.

If there was a big bang why not place it inside our universe with the
laws of physics that are known to exist and postulate a cataclysmic event
within it. That at least is feasable given our current knowledge.

Because it is not consistent with what we know of the universe. It
might be consistent with what misconceptions you have about the
universe, but for better or worse, physicists do not deal with
common sense conceptions of the universe. They deal with what they
can observe and measure.

It's bizarre that no one would say, "OK, I don't know chess, but I'd
like to challenge Kasparov tomorrow," but there is no shortage of
people who are convinced they know what is wrong with modern physics.
There is almost certainly stuff wrong with modern physics, just as
there are imperfections in Kasparov's play, but laying claim to knowing
those flaws without spending years to fully understand the state of the
art is just as irrational in one case as it is in the other.

--
Brian Tung
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