What Is Humanity's Place in the Cosmos?

For thousands of years, people have looked up at the night sky and wondered: Where do we fit in? Now, one of the world's leading astrophysicists is helping answer that question. Priyamvada Natarajan, a professor who studies black holes and dark matter, sat down with journalist David Brooks on the podcast 'The Permanent Questions.' Together, they explored some of the biggest ideas in science — and what those ideas mean for all of us.

Natarajan grew up in India and loved maps and atlases as a child. When she was a teenager in Delhi, she taught herself spherical geometry and wrote a computer program to create a star map of the night sky over her city. That project sparked a lifelong passion for exploring the unknown. She later studied at MIT and Cambridge, where she earned her reputation as a brilliant scientist who also deeply loves the humanities — history, poetry, and philosophy.

One of the things Natarajan studies most is black holes. A black hole is a place in space where gravity is so strong that nothing — not even light — can escape it. Scientists cannot see black holes directly. Instead, they detect them by watching how their powerful gravity bends light and pulls in surrounding gas. Natarajan explained that almost every galaxy in the universe, including our own Milky Way, has a giant black hole at its center.

One of Natarajan's biggest breakthroughs came from a surprising place — a bathtub. While living in England as a graduate student, she noticed that when she pulled the drain plug, some water rushed straight down before the rest began to swirl. That observation helped her think of a new way that giant black holes might have formed. She proposed that massive clouds of gas could collapse directly into a black hole, skipping the step of forming a star. It took 17 years, but the James Webb Space Telescope finally confirmed her idea was correct.

The universe is almost impossibly large. Scientists estimate there are about 2 trillion galaxies, each containing hundreds of millions of stars. When Brooks asked if that makes human life seem unimportant, Natarajan said she sees it both ways. Yes, Earth is one tiny planet in a vast cosmos. But humans have used a small, remarkable brain to figure out the laws of the universe — and that is something to be proud of.

Natarajan also shared a fascinating fact: the calcium in our bones was made inside stars that exploded billions of years ago. In the very early universe, only the lightest elements — hydrogen and helium — existed. Over time, stars forged heavier elements like calcium and iron in their cores. When those stars exploded in events called supernovas, they scattered those elements into space, and eventually those elements became part of living things — including us.

Brooks and Natarajan also talked about what happened before the Big Bang. Scientists do not yet have a complete answer, but some believe our universe may be just one of many — an idea called the multiverse. Natarajan said she finds this idea scientifically comforting. If there are an infinite number of universes, the very specific conditions needed for life in ours are simply one lucky outcome among countless possibilities.

Science and the humanities may seem like very different fields, but Natarajan argues they belong together. She told a story about hand pumps installed in Indian villages during droughts. The pumps worked perfectly from an engineering standpoint, but nobody used them — because the posture required was considered improper for women wearing saris. Only understanding people and culture could explain that. She believes the world's biggest problems need both scientific and human knowledge to solve.

Natarajan also pushed back on the idea that scientists are cold or unemotional. She pointed to Einstein, who wrote that a scientist's deepest feeling is 'rapturous amazement at the harmony of natural law.' Natarajan agreed, saying science is a creative process just like writing or art. Scientists feel passion, excitement, and frustration — especially when waiting years for data to prove their ideas right.

When Brooks asked about her favorite space movie, Natarajan quickly chose 'Interstellar.' Her colleague and Nobel Prize winner Kip Thorne served as a scientific adviser for the film. The team working on the movie's visual effects did real math to show how black holes bend light, and those calculations led to a genuine scientific discovery that was published in a peer-reviewed paper. For Natarajan, that was a perfect example of science and creativity working together.