Ideas

Light is the great unifier. John Wheeler, the beloved Princeton physicist, used to draw the universe as a big capital U with a little eye on one leg, signifying that we, human beings, are the eyes of the universe looking back at itself. The universe...

I gave a copy of the preprint of my paper to Robert Oppenheimer, who, as Director of the Institute for Advanced Study, was my host. A week later I met him at an Eastern Physics Meeting at the University of Maryland, my home institution. When I asked him if he had read my paper, he replied, “Greenberg, it’s beautiful!” I was elated. After a pause, he completed his assessment of my paper by saying, “But I don’t believe a word of it!”

Jo Bovy, John N. Bahcall Fellow in the School of Natural Sciences, explores the stars, planets, and gases that make up galaxies, the dark matter that holds them together, and the history of our own Milky Way.

One of the biggest discoveries of humankind is yet to come: Finding compelling evidence for life on another planet. In this lecture, Hanno Rein, former Member (2010–13) in the School of Natural Sciences, discusses the many places to look for...

How did the universe begin? Robbert Dijkgraaf, Director and Leon Levy Professor, explains what we know about the Big Bang and explores the mysteries of our universe.

“Space Ripples Reveal Big Bang’s Smoking Gun,” read the New York Times headline last March 17. In a seemingly momentous news conference at the Harvard–Smithsonian Center for Astrophysics, researchers using a BICEP (Background Imaging of Cosmic...

There is an interesting connection between two of the best-studied nonlinear partial differential equations in physics: the equations of hydrodynamics and the field equations of gravity.

Let’s start with a brief review of hydrodynamics. At the...

Proteins are typically cited as the molecules that enable life; the word protein stems from the Greek proteois meaning “primary,” “in the lead,” or “standing in front.” Living systems are made up of a vast array of different proteins. There are...

One of the most striking facts that we know about the cosmos is that most of the chemical elements that ­constitute matter, including our bodies, were produced inside stars and ­distributed by their explosions. It is amazing how much we know about...

In recent decades, physicists and astronomers have discovered two beautiful Standard Models, one for the quantum world of extremely short distances, and one for the universe as a whole. Both models have had spectacular success, but there are also...