Fellowship supports USC professor’s study of black holes
Nicholas Warner, professor of physics and astronomy at the USC Dornsife College of Letters, Arts and Sciences, has been named a 2013 Simons Foundation Fellow.
Among 55 mathematicians and theoretical physicists to receive the honor this year, the fellowship provides funding to researchers to extend a period of academic leave from a single term to a full year. The goal is to provide researchers with enough time to concentrate their efforts and make significant breakthroughs.
“We are delighted that Nick has received this critical support from the Simons Foundation to continue his fascinating research on black holes,” said USC Dornsife Dean Steve A. Kay. “[He is] one of our most treasured faculty members and mentors, [and] I have no doubt that the new knowledge Nick uncovers during this time will not only result in critical advances in theoretical physics, but will benefit his students here at USC.”
Since January, Warner has been working at the Institut de Physique Théorique, CEA/Saclay, in France, and is also planning brief trips to the Institute for Theoretical Physics at the University of Amsterdam, Imperial College, London, the University of Cambridge and CERN in Geneva.
“The Simons Fellowship is the kind of thing that makes a huge improvement in the quality of life of research of scientists,” Warner said. “It’s a fantastic opportunity to make a significant advance in my work, and I’m very grateful for it.”
Warner’s yearlong sojourn is allowing him to collaborate with colleagues throughout Europe on exploring the physics of black holes and holographic field theory — one of the consequences of string theory that predicts that the description of a volume of space can be encoded two-dimensionally.
“We’re looking at black holes and the structure of space-time from different perspectives and using different mathematics, but we find ourselves at conferences saying the same kind of things,” he said. “We will probably have to completely rewrite the book on the black hole at the event horizon — that’s a growing sentiment in the community.”
There are two main branches of physics that scientists use to describe and predict the actions of the universe: general relativity and quantum mechanics. General relativity works well on the large scales of planets, stars and the universe, while quantum mechanics works well on the microscopic scale of atoms.
The problem is that general relativity and quantum mechanics make opposite predictions when applied to very massive but extremely compressed objects — the sort of objects you get when you crush the Earth to the size of a golf ball, or the Sun to the size of a small town; objects such as black holes.
A black hole is an object that is so massive that it collapses in on itself, trapping light as well as matter, and becomes so highly compressed that our present understanding of physics breaks down. Scientists once believed that breakdown occurred only once you reached the center of a black hole, known as the singularity. Now scientists are starting to suspect that they need to rethink everything from the event horizon, which is the outer “point of no return,” beyond which nothing can escape.
“String theory gives us some ideas on how to do it,” Warner said.
Early notions suggested that everything was completely lost and destroyed once it fell into a black hole, but this property made black holes impossible to exist under the laws of quantum mechanics. Scientists now believe that information about matter that falls into a black hole must survive, encoded perhaps holographically, and that there must be new physics that emerges where the event horizon was expected to be.
These ideas led scientists to suggest that information falling into a black hole could be encoded onto the horizon, but this can lead to other paradoxes.
“Many of us now believe that something more radical is needed, and one possible solution using string theory is sometimes called the ‘fuzzball’ proposal,” Warner said.
String theory predicts that there are many more dimensions that one normally perceives. The fuzzball proposal uses string theory to replace the entire interior of a black hole with multidimensional geometric structures of such complexity that they can store and eventually recycle the information about what fell in.
“Unfortunately the black hole still rips you apart in much the same way, but the information about it is no longer lost,” Warner said. “It’s like being completely absorbed into the Matrix. Your body is still disassembled, but everything about you is stored holographically. That information eventually leaks out of the black hole via Hawking Radiation, and so entropy increases and information is preserved.”
Warner plans to return to USC in January and teach Astronomy 100, a general education class, next spring.
Though understanding the physics of black holes may seem like an esoteric problem, scientists are eager to reconcile general relativity and quantum mechanics, both of which we rely on every day to use everything from GPS devices to computers.
“It’s not a limit that you or I will encounter in our lifetime, but if you’ve got two things that you know to be true — but they conflict — it’s an itch you absolutely have to scratch,” Warner said.