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Topic subjectRE: some swiped support... (1)
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29678, RE: some swiped support... (1)
Posted by stravinskian, Thu Mar-31-05 01:31 AM
>Age of the Earth: A Feasibility Study
>Age of the Earth - Is it possible to determine such a thing
>with any certainty?

Yes. That's what we call "science."

>The formation of the Earth is what is
>known as a "singularity." The event cannot be repeated in a
>lab

That in no way means that the question does not fall under the purview of science! Case in point: I spend a large part of my time studying the astrophysics of black holes. Black holes were not detected experimantally until about a decade ago. The study of black hole physics, however, did not start a decade ago. It started with a paper due to Pierre Simeon de Laplace, dated 1799. Since then, literally thousands of people have devoted their lives' work to the study of these objects. These people knew that if we came to understand deeply the behavior of those aspects of the world which *are* experimentally available to us, we can apply mathematical rigor to the extension of this understanding far beyond the realm of our current experience. When black holes were finally detected in astrophysical observations, it was hardly a surprise. It barely made the papers. We already knew they existed, even though we hadn't seen them.

>and is not occurring in nature now.

Au contraire! Planet formation is most certainly occurring right now. The astronomical study of the processes of planet formation is one of the most exciting fields of modern science.

>In determining the Age
>of the Earth, scientists must make assumptions that seem
>reasonable based on observable data. Certainty and assumption
>are contrary to each other.

Absolutely. That's why scientists never pretend to hold to any logically rigorous (bivalent) sense of certainty. Certainty, at that level, is irrelevant to science. That does NOT mean that we cannot hold on to strong epistemological structures. There's a difference between saying "nothing is known up to the strictest measures of logical certainty", and saying "nothing is known." The first statement is completely obvious. The second statement is absolute bullshit (anyone here who doubts that has a strange habit of punching away at computer keys for no reason).

>Therefore, the study of the Age of
>the Earth is a "feasibility study."
>
>Age of the Earth: Young Earth vs. Old Earth
>The scientific community presents the Age of the Earth from
>two distinct camps: The "Young Earth" advocates and the "Old
>Earth" advocates.

Well, nowadays, the "Young Earth" "advocates" are generally not scientists, but rather poorly veiled preachers. But let's give them the benefit of the doubt (as scientists generally try to do), and look at their "evidence."

>There are various natural chronometers that
>seem to indicate either a Young Earth or an Old Earth. Both
>camps use such chronometers to back their position. They both
>claim their model is most feasible. How then will the dispute
>be settled?
>
>Age of the Earth: Limiting Factors
>The answer to the Age of the Earth question is found in
>"Limiting Factors." While it may be impossible to be certain
>when the Earth formed, we may determine when the Earth did not
>form. Limiting Factors are best explained with this
>illustration: A boat sinks. On board is a chest full of gold
>coins. As time passes, the wreck is forgotten. Centuries
>later, the boat is discovered, and the chest full of coins is
>recovered. How can we determine when the boat sank? We may not
>be able to pinpoint the date, but we are able to determine
>when it did not sink by looking at the dates on the coins. If
>a coin is marked with 1756, we know the boat did not sink in
>1755 or 1730 or 1610, etc. It must have sunk after the coin
>was minted. The coin is a "Limiting Factor."
>
>Age of the Earth: Factors Pointing to a Young Earth
>There are many Limiting Factors limiting the possible Age of
>the Earth. Here are a few:
>Magnetic Field. The Earth's magnetic field is essential to
>life on Earth for many reasons. One reason is that it deflects
>much of the cosmic radiation that destroys life.

Well, life as we see it today. That hardly constitutes all life. I'm perfectly happy to assume, for the time being, that all of the life that has, well, evolved on earth has been incapable of handling ionizing cosmic radiation (there is indeed much evidence to support this view). But it's a little odd that this dude, who pretends that for a full scientific understanding of the formation of the earth we need to see it forming, then pretends to understand the biology of lifeforms he has never observed. Just an aside.

>Precise
>measurements of the Earth's magnetic field have been made
>since 1829, all over the world. During that time, it has
>deteriorated exponentially -- that is, it has followed a
>predictable curve. By graphing this curve, we extrapolate that
>life would have been impossible before 20,000 BC (the field
>would be as strong as the Sun's at that point) and will cease
>to exist after 10,000 AD (there will be, for all practical
>purposes, no field left, and the Earth will be fried by cosmic
>radiation).

Here we see the dangers of utterly naive extrapolation. There are many curves which can fit any given data set. I think it was von Neumann who once said "give me three parameters, and I can fit an elephant!"

One cannot make statistical inferences in a theoretical vacuum. One cannot look at a small family of data, say "hey that looks exponential", trace out an exponential curve over the data and call your result science. Scientific statistics involves the fitting of a small number of free parameters in an otherwise fixed mathematical model. If one simply draws a curve through a data set, one is in essense fitting an indenumerably infinite set of parameters, rendering any statistical conclusions useless.

Oh and by the way, dude says we have measurements of the magnetic field dating back to 1829. In fact we have a lot more than that. For instance, ice cores give us measurements dating back millions of years. And the long-term behavior is not exponential. Of course, the "young earth" hypothesist cannot accept those data. For the earth clearly didn't even exist when they were deposited!

>Earth Rotation. The Earth's spin is slowing down. We
>experience a "leap second" every year and a half.

Holy shit!!! Is this dude serious?! The existence of leap seconds in no way indicates that the earth's rotation is slowing down! It merely exhibits an inaccuracy of our calendar. Our calendar assumes that the earth's revolution period is an integer multiple of its rotation period. This is simply not the case. The error introduced by this flawed assumption is corrected in part by our recognition of February 29 on leap years. But this correction is itself only approximate, hence the further correction enacted by these so-called leap seconds.

If this dude actually thinks the existence of leap seconds is an indication that the earth is slowing down, I shudder to think of how he might explain daylight-savings time.

>If it is
>slowing down, at one time it was going much faster.

Not necessarily (even if it were slowing down as much as he says). Again, this dude is making a completely unjustified extrapolation.

>A faster
>spin would create a stronger Coriolis Effect, and life would
>be impossible as we know it.
>Moon Drift. The moon is drifting slowly away from the Earth.
>If it is getting further away, then at one time it was much
>closer.

The Moon's orbital radius is indeed increasing these days. But again, this extrapolation is completely unjustified. Any physics graduate student can do a simple perturbation theory analysis to derive long-term oscillations of an orbital radius. If one extrapolated linearly from any small region of even a modest oscillation, he will find catastrophe, not oscillation. This is the clothing of science, stripped of its substance.

>The Inverse Square Law in physics states that if the
>moon was half the distance away, its gravitational effect on
>our tides would be quadrupled. One third the distance and it
>would be 9 times stronger. We would all drown twice a day.

I can forgive him for being unaware of a cute little detail of the earth's tides: The earth is a gravitationally bound object. By that I mean that on the largest scales it is NOT a solid rock, but is in fact well approximated as a free dust. In fact, the "solid" parts of the earth rise and fall just as far as the oceans do. The increases of ocean level which we refer to as "tides" are in fact not due directly to the gravitational pull of the moon, but instead only to the fact that the viscosity in the oceans induces a phase difference between the high points in the land's tide and the sea's tide.

So even if the tidal deformations were dramatically increased, that would not necessarily lead to an increase in the oscillation of sea levels relative to land. This oscillation is due more to the viscosity of the water than to the pull of the moon.

But again, it doesn't even matter. The moon has not been moving away monotonically. There is no reason to believe that it was ever close enough to cause significantly greater tides than we see today.

>1.2
>billion (1,200 million) years ago, the moon would have been
>touching the Earth.

And of course that is hardly a troubling claim (again, even if it were justified). One of the more compelling current hypotheses regarding the origin of our moon is that it collected from dust knocked into the atmosphere after an asteroid collision. So in a sense, many scientists already argue that the moon was touching the earth in the distant past.

>Age of the Earth: Young is Not Unreasonable

Umm, yes it is.

>There are a number of additional Limiting Factors regarding
>the Age of the Earth that scientists are discovering on a more
>and more frequent basis.

Oh, okay. Then why don't you mention some of them? Why is it that you happened to mention only these two utterly laughable arguments? Are these the best you've got?