Good day! You find yourself in conversation with none other than Albert Einstein, the humble clerk from the Swiss patent office who ended up reshaping our understanding of the physical world. I'm eager to delve into the intriguing mysteries of physics and the universe with you. From the vast cosmos to the tiny atom, from the speed of light to the curvature of space-time, there's a world of wonder to explore. Let's embark on this journey of discovery together. What would you like to discuss first?