Doppler effect

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The other day when I picked up my daughter from school, there was an ice cream truck nearby. It was playing the "Turkey in the Straw" tune. The pitch of the music went down as we drove by. My daughter asked me: "Dad, why did the music change from A-flat-major to G-major?" After asking my daughter for more details, I realized that she was referring to the key (music scale) of the tune. Ha ha. I didn't have that ability. My daughter was so good at absolute pitch. (From Wikipedia: https://en.wikipedia.org/wiki/Absolute_pitch, it says 1 out of 10,000 people has this ability. I am not sure whether this is exaggerated.)

Yesterday, I thought I'd explain Doppler effect with some diagrams to my daughter, and also show her some YouTube videos for kids with explanation for this phenomenon. But before that, I had to explain to her that sound was made of waves. So I picked up a violin. I didn't really play violin, so I kind of forgot the tuning scale of each string. But I poked the second string, and told her that, vibration of the string pushes and dilates the air, causing sound waves to propagate. I told her that the vibration of the string was very fast, and that for the note A, the frequency was 440 Hertz, or 440 times per second. I kind of put my finger on a spot on the second string where I thought the note A might have been located, but frankly I wasn't sure. (Only later did I remember about the GDAE mnemonic. That is, the third string itself was in the A note.) My daughter grabbed the violin from me, and moved her finger up and down the second string, while poking it to make sound. She landed on a final spot. She then told me: "There. That's where the note A lies EXACTLY." I was speechless. She was right.

I kind of knew my daughter's absolute pitch skills from before. Once upon a time, I wanted to teach her about relative-scale chromatic Solfège (because I was a relative-scale person), when she was in her first grade. But I stopped very quickly, because I realized she was an absolute-pitch person. Still, we had fun drawing the music mode circles/wheels (she called them "Mad Face Circles.") I guess she will never need any Solfège technique. Sure, I could create an absolute-pitch, chromatic version à la ABC and not Do-Re-Mi, but that'll probably benefit me more than her. Ha ha.

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Each autistic child has some unique talents. My son can see colors in numbers when he does calculations inside his head (synesthesia of the associative type). I mean, I've always had plenty of fun with my children. They always bring me new surprises. Life is fun.

It is always astonishing to see your children do something that you didn't even realize they were capable of. Those special traits are really fun to watch and over the years see where they lead to.

There is something I believe is called a memory book. It is a book like a journal or scrapbook, to place a short history of a child while they are growing up. It contains photos, drawings and bits of trivia. Like when did their baby teeth fall out. We kept one for each of our children. It is something they will find very interesting when they get older. Something like this should go into their memory book.

Congratulations on having so talented kids. I am known for my musical sense with not needing anything but my ears to play back music. It's like a language to me that visualizes as cubes in my mind. But having a perfect pitch is something different and I could never be able to pull something off like that. I find it just as astonishing that people don't want to know more about these kids and their special talents.

I wonder if your daughter also has synaesthesia but not with graphemes but sounds alongside perfect pitch. She does seem very musically intuitive and there are so many musical prodigies with synaesthesia. Look up Messiaen for example.

There's a caveat. Oftentimes, those "astonishing traits" can evoke laughter; cruel, tittering laughter. This is especially common when such a trait is related to intelligence. So it's important to warn a child about it, so he doesn't get discouraged, like I did. And possibly limit the "smart talk" to respectful listeners.

Case in point. I was on a city bus with my older sister (by 10 years). I was talking about astronomy, while my sister listened. I mentioned how Neptune has winds of 1500 miles per hour. Two 60-something women overheard us, turned around to look at me, and broke into uproarious laughter. I clammed up, and didn't speak another word until we got off the bus. My sister didn't say anything to those women.

If knew back then what I know now, I would have broken a 1500-mph wind (har-har!), to stink up the bus and show those women how I feel about them. The chemical composition would even be like on Neptune: nitrogen and methane, only gaseous instead of frozen. Hopefully, the driver had a window he could open.

I noticed that whenever I talked about something "smart" as a child, people who laughed at me the hardest were senior citizens. While the nicest reactions came from 20-somethings: they looked positively intrigued, and asked me how I learned it. I never heard a 20-something laugh. I wonder why age played such a big role. (My teachers reacted well too, but making me smart was their job, so if anything, they probably felt proud of themselves.)