Imagine this: The 1920s in Kolkata. A young boy, utterly enthralled, crouches on the ground. His cart-drum (Gaadi-Baja) beats and rumbles as wooden wheels spin. In an attempt to understand the magic of the Cart-Drum, he tilts it this way and that while observing its physics. In 2025, we will be in the same city. We are the same age and share the same curiosity, but now there is another child. She is hunching over a laptop, learning how to make a LEGO Mindstorms robot avoid ob