Having worked as both a theorist and an experimentalist, I find theoretical work to be the most challenging emotionally because it's the most isolating. In my last postdoc, as an experimentalist, I relied on and interacted with other people for such daily tasks as preparing reagents. Work-based socializing was common. Now, as a theorist, I write computer code and solve equations by myself. Sometimes I go for days without any meaningful human interaction.

Isolation is not new to me. I grew up in a rural area, and when I felt sad or lonely I would head into the woods to look for birds, snakes and salamanders. Knowing the creatures around me made the world seem a little bit friendlier and less alien. But now, surrounded by the concrete of Baltimore, I no longer have an easy escape into the woods. So when a friend invited me to explore the Potomac River, about an hour away from Baltimore, I eagerly agreed.

Floating downriver on rubber inner-tyre tubes, we watched an osprey plunge into the water, saw a young bald eagle perched on a bank, heard the distinctive call of a barred owl and glimpsed a nighthawk hunting over the river at dusk. Thanks to this river retreat, my life of equations and computer code back in the city seems better, even days later. To paraphrase the author and naturalist Henry David Thoreau: not yet subdued by man, nature's presence refreshes him.