Resonance

I’ve recently become fascinated by the idea of resonance—not the idea of reverberating sound, but of the reinforcement of sound by the synchronous vibration of a neighboring object. I know, right. What on earth does that mean?

The best analogy I’ve heard to explain resonance is that of pushing a child on a swing. First, the size of the person in the swing doesn’t matter. The pace at which the swing completes a cycle (the time the swing moves forward and then returns to its starting position) is always the same. This cycle represents the natural frequency of the swing.

Secondly, when pushing a child on the swing, we know the best point to add our thrust. By adding force at the precise point in the cycle, the amplitude of the swing increases (i.e. the swing goes higher). If a second person stands at the front of the swing and does the same thing, this adds even more to the amplitude.

But resonance doesn’t apply only to swings. This link shows a wonderful example of resonance of sound waves. Resonance with metronomes

If you are not a patient person, feel free to skip ahead to about the 2:00 minute marker. At this point, the metronomes are almost all in sync, even though each was started at random. Even here, one rebellious metronome beats at its own rhythm. Then, by 2:37, even this hold-out marches to the same rhythm as the other 31 metronomes.

The first time I saw this, I thought it was nothing short of miraculous.

Watching this sent me on a journey to understand resonance. After pondering this idea for a while, I wondered if resonance ever had a destructive effect. It didn’t take long to discover the answer.

The best example of what can happen with out of control resonance is the collapse of the Tacoma Narrows Bridge, nicknamed Galloping Gertie. When the wind blew long and steady, this drove the bridge to oscillate at its natural frequency, which ultimately caused it to collapse. Glad this wasn’t on my commute. Tacoma Narrows Bridge-Galloping Gertie

Today, engineers put in dampeners when designing bridges. The dampeners interrupt the resonant waves and prevent the waves from growing.

I then asked myself how else might resonance relate to our world today.

It occurred to me that ideas, especially those of a political or religious persuasion, can have a similar effect. People sometimes believe things so strongly that their collective beliefs reach a destructive amplitude. Fear can drive people to abandon logic. The added influence of other like-minded individuals acting out on these same beliefs exponentially adds energy to this fear. This fear can then cause even normally empathic people to suppress opposition at any cost. Violence becomes acceptable when people convince themselves that the end justifies the means. It doesn’t matter which side of the political aisle you are on, suppressing opposition at any cost is ultimately destructive.

What is an equivalent force that can serve as a dampener in society? The answer seemed obvious: a free press. The press is often considered the fourth branch of government. In our democracy, each of the branches of government provides a check and balance on the others, with no one branch of government becoming too powerful. The last fail-safe is a free press that always seeks to discover and report the truth, regardless of which side it finds in the wrong.

When the press abandons its responsibility, and reports only stories that give support to a single political leaning, the resulting effect is much like the destructive resonance that caused Galloping Gertie to collapse. When people believe that the only goal must be that everyone adopts the same belief system, the result is similarly destructive, ultimately leading to societal collapse, or even MAD—mutually assured destruction.

Instead, if we allow each other the right to hold differing beliefs, if we encourage the open exchange of ideas, and we ensure that the press seeks and presents the truth regardless of political leaning, the effect will be the opposite: Harmony.