New Delhi: At the NXT Forum 2025, held at Bharat Mandapam in New Delhi, renowned physicist Prof Brian Greene spoke on the beauty of classical physics. He expressed his delight at visiting India for the first time, praising the hospitality he received.
“This is my first time in India. The hospitality has been absolutely amazing,” he remarked.
Discussing the future of physics, Greene emphasised the importance of exploring quantum mechanics and its technological applications.
“The next big developments will take place in the realm of quantum physics and quantum mechanics, pushing the frontiers of our understanding. It’s crucial that everyone has at least a basic grasp of these new ideas,” he stated.
He explained that his talk aimed to provide an overview of the discoveries made in the last hundred years of quantum physics, as well as insights into where the field might be headed.
“So, toward that end, I’d like to give you a sense of what we have found in the last hundred years of quantum physics and then a sense of where we might be going in the future,” he added.
Contrasting quantum physics with classical physics, Greene provided a historical perspective.
“Classical physics is what we typically associate with Isaac Newton’s discoveries in the late 1600s and early 1700s. It remains the foundation of what we teach students worldwide today. The beauty of classical physics is that it is deeply ingrained in our intuition and everyday experiences,” he explained.
To illustrate this, he described a simple action.
“Take any ordinary object—if I toss it in the air and catch it, no one is surprised. But why is that? It’s because we all naturally understand the laws governing this motion. However, if you think about it, it’s an incredible achievement. The movement of the object and my hand aligning perfectly to catch it involves a complex interplay of forces, yet we perform it effortlessly,” he said.
Making the transition to quantum mechanics, Greene explained how classical physics does not apply in the microscopic world.
“You might assume that the principles governing the everyday world extend to the microscopic realm. However, that’s precisely what was discovered to be untrue over the last hundred years,” he noted.
He elaborated on the emergence of quantum mechanics in the early 20th century.
“A new physics emerged from studying the microscopic world, and that is quantum mechanics. I want to highlight some of its fundamental ideas,” he said.
Greene further underscored the continuity of physics by referencing a foundational equation.
“We can encapsulate these ideas using a basic mathematical equation that Isaac Newton first formulated—F = ma. This equation remains essential, and we still teach it to high school students around the world,” he concluded.