From: Ronald Wong (ronwong@inreach.com)
Date: Wed Jan 31 2001 - 20:27:58 PST
Message-Id: <l03102801b672b2b9f451@[209.209.18.171]> Date: Wed, 31 Jan 2001 20:27:58 -0800 From: Ronald Wong <ronwong@inreach.com> Subject: re: Not Knowing
A little while ago Sidney Keith replied to my comments on "Not Knowing" by
saying:
>
>Ron, we have to be careful in saying what is impossible, ...
If you do a seach of my original article for the word "impossible" you will
find it isn't there.
Since the article focused on what was possible in the realm of science,
this should not come as a surprise.
The point I was trying to make is that science can address a lot of
questions about the nature of the world that we live in but it cannot
address ALL of them.
With that in mind, I went on to point out that it's important for us as
scientists, teachers, and just plain citizens to know what kind of
questions and statements are actually scientific. Not all of them are -
including those addressing known scientific facts.
----------------------------------------
>On your list of topics beyond the realm of science is one that a scientist
>may already know, the nature of gravity.
The list I drew up consisted of statements or questions about fundamental
aspects of nature that are considered to be scientifically true. These
fundamental laws/principles are NOT "...beyond the realm of science". All
of them can be found in our current textbooks in physics - and this
includes the "nature of gravity".
What you won't find in a physics book is WHY the fundamental properties of
nature should manifest themselves the way they do. This kind of "why" is
not within the purview of science.
Let's consider gravity for instance: I tried to show in my post how our
concept of the "nature of gravity" has changed significantly over time.
In the many centuries following Aristotle, it made no sense to ask "Why is
the Natural Order the way it is?". In the few centuries following Newton,
it made no sense to ask "How is it possible for a mass to reach out over
great distances and exert a force on another mass?" And in this past
century, it made no sense to ask "Why space-time?".
You can fashion such questions and claim that they have a place in science
but you would be hard pressed to find anyone in science who would agree
with you.
You won't find any evidence from Aristotle as to why the Nautral Order is
the way it is. It simply is (all you have to do is just look around to see
that it is). Newton came right out and said that he was unable to frame a
testable hypothesis that would explain why the force of gravity could have
the properties it had (he asked his readers to simply accept the fact that
it existed and had the properties that his law described). Einstein
characterized gravity in terms of space-time. He was able to show that
Newton's concept of universal gravitation was a byproduct of space-time
geometry (and Newton's gravitational force a fictitious byproduct as well)
but he too never bothered to find out why space-time was what it was and
neither has anyone else.
We've known about gravity for at least a few thousand years. During this
time our understanding about the "nature of gravity" has been changing. The
catalyst for this change has been, as always, improvements in our ability
to observe and map the behavior of nature. What has never been addressed
during this time is why these fundamental forms are the way they are. It's
not what scientists do.
----------------------------------------
>Ed Witten, the father of superstring theory, writes that the most exciting
>moment in his life was when he saw how gravity fell out of the superstring
>equations.
What Ed Witten was saying was that when he reduced the superstring theory
down to the mundane circumtances that you and I are familiar with, he ended
up with a mathematical expression exactly like that which Newton arrived at
when he applied his three laws of dynamics to the motion in the heavens.
That's what he meant by "he saw how gravity fell out of the superstring
equations". To this degree, he knew he was on the right track in his
development of superstring theory - it led to a result which Newton had
arrived at 300 years ago. THAT's why he was so excited.
----------------------------------------
>It's true that much of superstring theory lies currently beyond the realm of
>testable hypostheses...
This just isn't true.
First, it's important to keep in mind that superstring theory is a "theory
in the making". It's not a theory which has the universal endorsement of
the scientific community. Although it, like many of its predecessors, has
been able to arrive at statements which we already know to be true
(Kepler's three laws for instance), what is missing is the validation of
a testable hypothesis stemming from this theory (or any of its predecessors
for that matter).
Secondly, Superstring theory HAS a number of hypotheses that are testable.
It must if it wants to be taken seriously by the scientific community (it
was the lack of such hypotheses at the start that prompted Richard Feynmann
to question it over a decade ago).
The hypothesis that everyone is focusing on presently is the existance of
another family of elementary particles (yes, MORE "elementary" particles).
Superstring theory claims that, in addition to it's anti-matter equivalent,
every fundamental particle of matter has a another particle called a
"superpartner". Superstring theory predicts that the superpartner will have
a mass greater than the fundamental particle it is associated with.
Unfortunately, the mass is so great that they cannot be detected using
current technology.
A NEW generation of particle acclerators are presently under constuction
that will be capable of detecting them - if they exist. The Large Hadron
Collider (LHC) at CERN in Geneva will be the first one to come on line. If
all goes well, it should be up and running by 2005 and we should have some
answers in the following years.
----------------------------------------
>...but if no one proposes a theory, it's a sure bet that it will never be
>tested, and if no one wonders about a topic, it's a sure thing that a
>theory >will never be proposed.
In general, you've got the cart before the horse.
Since time immemorial we have been wondering about things/"topics". It
seems to be built into our very nature. These "wonderings" have led to
hypotheses and these hypotheses have led to theories. That's why the world
is full of theories. Some of these theories are scientific - they're the
ones that have been tested scientifically and found to be valid.
True, there have been times when the theory came first, followed by
testable hypotheses, but these are the exception to the rule. String theory
is a good example of this.
Like Maxwell's Electromagnetic Wave Theory, string theories are attempting
to unify a body of scientific knowledge that has already been adequately
shown to be true. In the case of string theories this involves the theory
of relativity and the quantum theory. Like Maxwell, scientists are trying
to cobble together a grander scheme using elements that are part of both
theories. Being able to derive the present scientific laws from these grand
schemes is the first step towards building a successful model - the cause
for Ed Witten's delight. But this is not enough if any model wishes to
become acceptable to the scientific community. Thus the present set of
hyptheses.
It took more than 30 years before the predictions of Maxwell were verified
(he never lived to see that day) so we shouldn't be surprised if it takes
some time before the grander schemes of the string theories are fully
validated.
----------------------------------------
>It was the aggressive anti-intellectualism of my science teachers in high
>school that turned me off of science for years. They seemed to be
>saying, "We are not part of the Western tradition of philosophy that goes
>back to Socrates. We are here to make toasters and bombs (it was
>during the Vietnam War), and that's all. You won't discover anything
>meaningful about life from us."
Unfortunately, there are "teachers" in our classrooms who have little to
offer in the way of educating their students. I would hope that by now you
would have figured out that the individuals who stood in front of your
science classes and held the attitudes expressed above were not teaching
you what science was/is. They were not SCIENCE teachers to begin with.
Under the circumstances cited above, you would have been lucky if all you
learned was what you found in your science textbook.
That would have been most unfortunate.
The material in our science textbooks is a pale shadow of what science is.
Helping a student to understand more fully the nature of science is what
science teachers do. This involves considerably more than conveying to
their students what can be found in their textbooks. Being knowledgeable is
not the same as being educated. It's the latter goal that good teachers
strive for.
----------------------------------------
>...While teaching the value of testing hypotheses is certainly appropriate, we
>shouldn't be dogmatic about the limits and the role of science.
True, but we SHOULD be dogmatic about the fact that science has limits.
We can define more clearly what science can do for us when we are fully
aware of it's limits. It's this lack of awareness that leads many to
ascribe too much or too little to the contributions that science can make
to society.
The word "scientific" is bantered about with very little thought as to what
it really means. It's our job as science teachers to spend a little time
with our students discussing it's meaning and to create in our classrooms
an environment that repeatedly reinforces their understanding of this and
so many other things as well.
It's part of the fun of teaching. - ron
This archive was generated by hypermail 2b29 : Tue Oct 16 2001 - 12:22:14 PDT