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[Phys-L] abstractions



I don't want to read too much into a single word.

Science, physics in particular, is VERY abstract to
most people. Attempts to make it more abstract and more mathematical
rather than tying the fundamentals back to personal experience would
be, IMO, the fools errand.

One hypothesis is that the word "abstract" was intended to
mean something like "remote" as in "disconnected" from the
real world. This is an important distinction, because to
my way of thinking, "abstract" is a good thing, whereas
"remote" and "disconnected" would be bad things.

To me, energy is real and relevant and non-remote. If you're
piloting a plane, energy management is a matter of life and
death; I don't know how more "connected" anything could
possibly be. Yet still, energy is 100% abstract.

===================

The other hypothesis is that we were meant to take the word
"abstract" literally. In that case, I have a different
response:

Science, physics in particular, is VERY abstract to most people.

Well, yes.

Yes, indeed.

That's a feature, not a bug.
Physics is supposed to be abstract. VERY abstract.
To all people, not just "most" people.
Not disconnected, not remote, but still abstract.

Every so often, people ask me "What is physics?" Mostly I try to
duck the question. It's not something physicists spend a lot of
time worrying about.

If pressed, I say that I can identify the middle of physics better
than I can delineate the farthest edges of physics. It's like
making waves by dropping enormous rocks into a vast ocean. I can
more-or-less find the middle of the wave pattern, but the ripples
spread out in every direction, and I don't know where they end up.

Very near the middle of physics, perhaps the biggest splash of all
comes from symmetries and conservation laws.
-- conservation of energy
-- conservation of charge
-- etc. etc. etc.

Here we are, less than ten sentences into a description of what
physics is, and things have already become quite abstract.
-- Energy is an abstraction!
-- Charge is an abstraction!
-- etc. etc. etc.

In the classroom, set up a nice flexible rope. Whack it with
a broomstick, to launch a wave. The wave is an abstraction.
The wave moves from left to right, even though the rope is in
the same place before and after. Also, the wave carries energy.
The energy moves from left to right, even though the rope is
in the same place before and after.

If you don't understand that energy is an abstraction, you will
never understand the first thing about energy.

Electrical charge is even more abstract. If you don't understand
that charge is an abstraction, you will never understand the first
thing about charge.

Attempts to make it more abstract and more mathematical rather than
tying the fundamentals back to personal experience would be, IMO, the
fools errand.

More abstract? More abstract than what?

AFAICT the core ideas of physics started out 100% abstract,
and I couldn't make them "more" abstract if I wanted to.

Perhaps more to the point, maybe this makes me the world's
biggest fool, but I don't see any way to make them less
abstract. AFAICT it's just a matter of learning to deal
with the abstractions. Yeah, energy is an abstraction.
Don't just deal with it; revel in it!

I know there are people on this list who insist that
their students are organically incapable of dealing with
abstraction, symbolism, representation, and/or imagination.
I just don't believe it. Very young kids play with dolls,
using their imagination. They know full well that the
baby doll is not a real baby; it's just a symbol, an
abstract representation of a baby.

Of course there are always a few special-ed students
who are so impaired that they are unable to play with
dolls. However, that's not what we are talking about
here. Those students shouldn't be signing up for high-
school physics, and they certainly shouldn't be dictating
the content and pace of the course.

I am aware of the research that talks about college students
who do not exhibit "formal operational" reasoning in class.
I am aware of it, but I don't give it much weight, because
it is the answer to the wrong question. My observations tell
me that students (even at the high-school level) are perfectly
capable of playing highly abstract games outside of class.
My explanation for the observations is that students have
been trained for years that independent thought, reasoning,
and creativity are not permitted on school grounds.

Meanwhile, the same kids use all sorts of creativity,
abstraction, symbolism, and imagination outside of class.

The physics book that you're using is probably 1000 pages long
and probably has 1000 errors in it.
a) At some level, this is a physics problem.
b) Suzy Q. thinks she will get burned at the stake if she calls
attention to the errors, even by ever-so-politely asking about
them. This is a huge problem, but it is not a physics problem.
Also (!) it is not due to any organic limitation in the students.
They have just been trained not to do it.

Back when I was a sorcerer's apprentice, back before I was old
enough to buy a beer, I made a bunch of money in the games industry.
I started by assuming that people had imagination ... not a few
smart people with imagination, not grown-ups with imagination,
but millions upon millions of ordinary children with imagination.
Seriously: You cannot play football using 27 little red dots and
a few pushbuttons. The "electronic" football game is an abstraction,
played out in your mind, using your imagination. The hardware with
the 27 little red dots does not play the game for you; it just
steers your imagination.

The ratio of what I designed into the game to what the player
gets out of the game is something like 1 part in 100. I reckon
teaching is the same. The ratio of what I teach to what the
student learns on his own is something like 1 part in 100.

For that matter, NFL football is a multi-billion-dollar industry,
but it's still just a game. It is a bunch of grown-ups playing
a children's game. Playing with a pigskin is not different in
principle from playing with dolls. The rules are artificial and
can be changed at any time (unlike the laws of physics). Most
importantly, even if you win, it's still just a game. It's like
chess; even if you win, it's still just a game. It's a metaphor
for combat, but it's not real combat, defending some noble ideal
by killing bad guys. It's not like being a doctor or even an
orderly in a hospital, defending good guys by killing bad germs.
It's not like building roads and bridges. It's not even like
teaching, which (if done right) makes the world a better place.
The NFL applies all sorts of window-dressing to make people
/imagine/ the game is important, but really it's just a game.
My point is that people routinely apply huge amounts of metaphor,
symbolism, imagination, and abstraction.

When people tell me their students are organically incapable of
handling abstraction, I just don't believe it. It may be a long
uphill slog to get them to apply such skills on school grounds, and
to apply them to anything more important than a mere game, and to
apply them systematically and wisely, but it can be done. You
can use non-abstract things like a pigskin or a ripple tank to
steer the imagination in a certain direction, but at the end of
the day, the abstraction is where the value is.

The idea is to cherish the abstractions. This is not just possible;
it's necessary. It's a big part of what an "education" is supposed
to be.