Science by staring at the ceiling

"Don't stare at the ceiling!" is a common admonition teachers use with students staring vacantly into space. That is because nothing says "daydreaming" like a student staring at a ceiling. It brings out the worst in teachers, and rightly so. And while we're all for paying attention in class, sometimes a little off-hours daydreaming can be a good thing.

It can be a good thing for Science, that is. Idle thoughts can produce lateral insights, which in turn become scientific breakthroughs, discoveries or inventions. Seeing the commonplace with fresh eyes is an Art - but it is an Art that spawns Science.

When something is new, it excites our senses and holds our attention; this changes when it becomes  familiar. Ever notice how the excitement of taking a window seat dwindles after the route becomes familiar? Or the excitement of seeing a rainbow, or the falling snow, or a sunset?

When the mind is the disease, absent-mindedness is the cure! The laws of Nature are hidden because familiarity prevents us from seeing them. Here's how a great Science discovery resulted from a certain somebody staring at a ceiling:-
A view of the Cathedral's ceiling
The year is approximately 1582 CE. Imagine Galileo seated on a pew inside the Pisa Cathedral. Bored, distracted, maybe even daydreaming, he stares at the gently swinging chandeliers suspended from the ceiling. As the energy of the swing slowly fades, the lamp swings in smaller and smaller arcs, finally coming to rest. In a gradually accumulating lateral insight, he notices something quite unexpected - the swings, from the longest to the shortest, all take the same time! This is contrary to what he expects (indeed, contrary even to modern intuition) - that longer swings should take longer, since a greater distance is being traversed.
We are not sure just how he verified this discovery. Maybe he first used his own pulse, then realized that the interval between any two beats was not uniform; or maybe, the excitement of discovery caused his pulse to race, so he abandoned the approach. Maybe he used a musician-friend's acute sense of timing to measure the duration of chandelier swings - we don't know for sure.

What we do know is that Galileo discovered the single most important (and surprising) aspect of suspended masses - their isochronism or "same time"-ness. He discovered that a pendulum's time period is independent of the width of swing, or the weight of the suspended object. This meant that the time of oscillation for a pendulum would remain the same until it stopped, and this caused a revolution in time-keeping. Further experimentation helped Galileo derive this formula for the period T:

T = 2(pi) x Square Root(L/g)

Scientists who came later built on this knowledge and created devices based on the use of a pendulum, and the pendulum slowly became the time keeping heart of our civilization. Foucault noticed an even more interesting aspect of pendulums, but that is a different story...

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