Sunday, February 24, 2013

Things that go boom

You guys. It turns out you can SEE SONIC BOOMS.

I've been entirely fascinated since the meteorite slammed into the atmosphere over Siberia last week. What is a sonic boom? Why so loud? Why so late? Wait, you can see it?! Hold. The. Phone.

So, of course, I had to go look it up. What is a sonic boom and how does it relate to sound? Turns out that the sound waves created by an object at a stand still make this perfect ripple, a la pebbles in a puddle. But, if the object starts moving, the waves start to bunch up ahead of the object, and lengthen behind it. Then if it gets going really fast, the waves ahead of the object are essentially all one: hello, speed of sound. Then, if the object goes faster than those waves, it creates a pressure differential that makes an audible craaaaack. But, get this: the change in pressure is no more than that when you're in an elevator going down 3 floors, except that it happens in a much shorter period of time. I know, I know. WTF. I feel like Taylor Swift here: totally bubbly and excited then totally confused then sort of understanding then just back to bubbly. People say all the time that things seem to "go against the laws of physics". What they don't realize is that we just don't know shit about the laws of physics. It's like the world of physics is the Stay Puft Marshmallow Man and we've totally figured out his left pinky toe. But I think we often understand physics on a cellular rather than academic level. Well, at least I hope that's true, 'cause I needed simple pictures to understand this stuff.

What really blows my mind, though, is how those waves get translated to thoughts and emotions. When that sonic boom shattered windows it didn't just register as noise: it registered as fear, confusion, and amazement. It's not something anyone that heard it will forget anytime soon.

They say that digestion starts with the mouth (you know, teeth, saliva, that whole bit). In the same way, hearing starts with the outer ear which collects and amplifies sound from around us. It then travels to the tympanic membrane, which looks much like a piece of plastic wrap. When the pressure around you changes or you get an infection, that membrane is what is causing a lot of the discomfort as it gets pushed past its tensile strength. Once through the eardrum the sound is transmitted to the ossicles. Three points if you can name the three bones of the ear without using a search engine. That's right: bones. I imagine them like a team of Morse code experts tapping messages into the inner ear. From the inner ear the sounds are transmitted to the auditory nerve for interpretation by the brain. Thus, in order to hear you have to be able to move the vibrations and the nerve has to fire messages to the brain. My 5 year old son, Jake, has had issues with his Eustachian tubes since about 4 months old. Specifically, those suckers just do NOT want to work well enough to drain the fluid that collects in the middle ear around the ossicles. As a result, at 6-9 month intervals he can't hear for shit. He hears through a thick wall of jello-like fluid that stays there until our dear ENT surgeon goes in and gets it out. He does a nice job of understanding the world even though he's hearing under water, but the difference when they remove that fluid is astounding. Interestingly, when the audiologists do his hearing tests they always do the cochlear nerve stimulation just to make sure he doesn't suddenly also have a nerve issue, and it is truly astounding to watch this kid go from hearing almost nothing and to having no issue at all. By bypassing the system and going straight to the nerve, he recognize sounds. It's no match for the amplifying, coaxing, and translating done by the outer ear and ossicles, but it works.

This all sounds pretty simple, except that it's totally not. Think about the range of sounds you hear in a day, and how they affect you differently. Seemingly similar sounds are made exceedingly specific by both the physical characteristics of the sound and how it interacts with the ear, and how we interpret it. Think about a child's cry: almost any parent can pick out their own child's cry out of cacophony of screaming children in seconds. Think about a rock concert: in a wall of sound you can still hear the pieces coming through. Think about a whisper: in the middle of the night I can hear my kids breathing two rooms away. Part of this discernment is based on actual physical waves of sound that match sounds of waves we've heard before or what we're anticipating hearing in that moment. But a lot of it is dependent on what was happening during that time, and how we felt. We make an imprint of the sound in our minds. Sound means nothing unless it's translated.

I had a conversation with a Pulitzer Prize-winning author last year during which we were discussing the usefulness (or not) of things that are exact. She posited that a symphony is by definition prescribed and predictable because the notes are immoveable, and that it is the job of the players to play those notes. At the time I was taken aback by the brashness of her answer and my retort got stuck in a stutter. It has stuck with me since and so here is my counter-argument: a symphony is not, in fact, a prescribed collection of notes and rhythms. It is at its core an interpretation, a magnificent show of collective expression in which all the pieces of the orchestra have to simultaneously attempt perfection and avoid it at all costs. Without the give and take of the individual musicians and the sections of instruments, the lift of the conductor, the sigh here, the strike there, there is nothing. The song is robotic without all those minute human errors and corrections. And, to be honest, the most astounding part is that our brains know the difference.

How we interpret those sounds are, in large part, emotional. All those nerve firings that help us understand the information coming toward us are connected to the parts of our brains that control emotions. On some level this has always made sense to me: music has been a way of understanding the world since I was a kid. On first listen to a song I can be moved to dance, feel the swell of emotion, or just cry. There are songs that so perfectly match my line of thought that all I can do is look around wondering, "Is anyone else hearing this?! This is it!" There are songs that make my fingers ache for the piano. Songs that make me sing at the top of my lungs while turning over the theme in my head over and over and over. There are songs that inexplicably unnerve me, and yet I keep coming back to them. There are songs that transport me back to childhood hearing my dad sing me to sleep. Songs where the sound of silence after the last note was sung by 100 campers is as palpable as it was 20+ years ago.  

*"Thrift Shop" is an awful, dirty song. NSFW. And still it makes me move.

So, it turns out you can't actually see the sonic boom unless there's enough moisture to bring it to life. But perhaps it is seeing to hear it, to feel it rock your world. To feel the pause before the roar. To internalize the force of energy. Whether it be something as overwhelming as a sonic boom, or hearing the intake of air, or all the songs in between, here's to listening past the speed of sound.

1 comment:

Adam Hirsch said...

Beautifully woven together piece, this! I would have said that you couldn't trace straight lines from a Siberian meteor through Macklemore to Jake, but damn: these nice curved ones work so nicely.