These days, while riding the 78 bus to work, I often find myself reminiscing about the past.

I work at a research lab in New Jersey studying engine oil additives. It's a bit different from the image I had as a child, but I am doing something akin to being a scientist. When I wear my lab coat and work in the lab, the day passes by in the blink of an eye. Having completed my PhD and now working as a researcher, I have suddenly turned 30, and now I am 33. My parents bring up marriage every time we talk these days.

Suddenly, I recall my childhood in Cheonan. During elementary school, my parents were always busy with their jobs, and I was mostly raised by my grandmother. After school, my steps toward the playground in front of my house were always light. The playground with the swing was my little world.

In the quiet moments, I would swing alone and look up at the sky. At that time, I was not even nine years old, but strangely, I wanted to be an adult. I often thought about how nice it would be to grow taller quickly, wear cool clothes, and live life on my own terms. The feeling of kicking the sky with my toes while swinging felt like my own spell wishing for time to pass quickly.

But now, it's the opposite. Time flies frighteningly fast, and there are many things I want to do and need to do.

While I am buried in work, demonstrating the intense focus typical of American companies, and come home to ponder my future, I suddenly miss the me from that time.

The me who would go out to the playground and swing without a care in the world. In that moment, the world was quiet and peaceful.

These days, I sometimes think about that. Occasionally, when I go to a nearby park on the weekend, I see children playing. Watching the kids scream while swinging makes me smile without realizing it. "I used to be like that." And I find myself wanting to swing just once in my heart.

It may feel inappropriate for my age now, but sometimes I want to take off the adult mask and return to that time. I think it wouldn't be bad to quietly swing alone in a corner of an empty park, looking up at the sky.

Life is truly strange. As a child, I wanted to grow up quickly, and now that I am an adult, I miss those times.

I am living as a chemist in New Jersey now, but in my heart, the swing from the playground in Cheonan still lives on.

And perhaps in the future... that swing might become a small time machine that brings me back to my original self.