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Michael Edmiston wrote:
My students think I am the graph czar, or at least a graph fanatic.
That's because they haven't met a REAL graph fanatic :-)
Let me tell a little story. Once upon a time in a mythical
place called La Jolla there was a fellow named John who
really liked numbers. The more digits the better. He wanted
unbiased numbers so dearly that he would have his grad
student, Richard, face the instrument with his eyes closed;
when John said "Now!" Richard would momentarily open his eyes
and observe the number. John would write it in the lab book.
After doing this for many days and weeks, they had lots of
lab books filled with lots of numbers.
They were looking for some sign of a superfluid transition
in liquid 3He at low temperatures. John had made a string
of important discoveries in low-temperature physics, and
finding the superfluid would move him from pre-eminence to
immortality.
Aside: The nice thing about theoretical predictions is that
there are so many to choose from. Predictions of Tc started
at about 300 milliKelvin. When that was disproved experimentally,
the predictions moved to lower temperatures. 100 mK was
disproved. 50 mK was disproved. 30 mK was disproved.
10 mK was disproved. In fact John and Richard had checked
experimentally down to less than 2.5 mK without seeing
anything. So the theorists gave up and lowered their
prediction to something in the _micro_Kelvin range.
Once upon the same time, in a mythical place called Ithaca,
there were a couple of guys named Bob and Doug. They liked
numbers OK, but they also liked graphs. They wanted to _see_
the data. And they didn't want to wait until the experiment
was over to analyze the data and see what it meant; they
wanted to see the data in real time. This is in the days
before computers, so if you wanted a graph you had to
suffer for it, fooling with Leeds chart recorders with
paper that always jammed and pens that always clogged.
One Thursday in late November, Doug was watching the chart
as the cell cooled through 2.5 mK. There was a glitch on
the T versus t trace. Doug circled it and wrote "Glitch!!"
on the chart. He warmed back up and saw it again on
the way up. And then again on the way back down. He
called Bob. Bob put down his plate of turkey and zoomed
into the lab. The two of them stayed up all night walking
back and forth through the "glitch".
I've seen that chart. It doesn't look like what I would
call a glitch. It's more of a corner. A small-angle
corner, just barely large enough to be seen. Eyes are
good at spotting corners in otherwise-straight lines.
Doug and Bob assumed, based on the aforementioned experimental
and theoretical evidence, that this wasn't the superfluid
transition. They figured it was something going on in
the nearby solid 3He. But they eventually figured out
that it was indeed the superfluid. Right there at
2.5 mK.
Everybody assumes that if John and Richard had been
plotting their data on a strip-chart recorder, they
would in fact have discovered the superfluid. But
they didn't.
Now, imagine what it was like working in Bob's lab
after that. All the significant variables had strip-
chart recorders attached to them. Even variables you
were pretty sure weren't significant had strip-chart
recorders attached to them.
Every so often, a new baby grad student, his fingers
stained N different colors from trying to unclog the
chart pens, would ask whether we really needed all
those chart recorders. Somebody would explain by
saying, Once upon a time in a mythical place called
La Jolla, .......