Andrea Puhm, laureate of an ERC Starting Grant 2019
CNRS researcher at École polytechnique’s Center of Theoretical Physics, Andrea Puhm was awarded an ERC Starting Grant that will allow her to put together a research team on “Information Encoding in Quantum Gravity and the Black Hole Information Paradox.”
After completing her PhD at the Institute of Theoretical Physics CEA/Saclay in 2013, Andrea Puhm did a postdoctoral fellowship at the University of California, Santa Barbara, and then at Harvard University before returning to France in 2017. With the ERC grant, dedicated to exploratory research and awarded on the sole basis of proven scientific excellence, Andrea Puhm will be able to further her research work on the fundamental properties of black holes and quantum gravity.
Black holes are among the most fascinating astrophysical objects. According to Einstein's general relativity theory, black holes are extremely dense, massive sources that curve spacetime around them so severely that in the center of a black hole spacetime ends in a singularity. The theory specifies that the horizon of a black hole behind which the singularity remains hidden is an absolute point of no return, and that any matter, energy and hence information absorbed by a black hole can never escape. From an outside observer’s point of view, a black hole appears to have no memory of what formed it.
As discovered by Stephen Hawking in 1975, black holes evaporate as a result of quantum effects, and can disappear completely, taking with them all the information they contain which is thereby irretrievably lost. But this contradicts quantum mechanics, which predicts that a black hole constitutes a series of microstates and that information is never completely destroyed or lost. This contradiction is at the heart of the black hole information loss paradox.
Given that this is a problem at the intersection of quantum mechanics and general relativity, it can only be resolved in the framework of a theory of quantum gravity, such as the string theory. This provides, by the holographic principle model, indirect proof that black holes obey the laws of quantum mechanics and do not destroy information, but these arguments are limited to rather exotic spaces. The first goal of Andrea Puhm’s ERC project is to establish whether the holographic principle also applies to the asymptotically flat spacetime relevant in our universe.
“To resolve the information loss paradox, we have to reach a better understanding of encoding, information recording and its evolution between the horizon scale and the asymptotic region where Hawking radiation escapes,” Andrea Puhm explains. The new research work she proposes combines two revolutionary ideas and explores the connection between them. It is based, on the one hand, on subtle long-distance effects that give rise to a horizon memory and, on the other hand, on a mechanism in string theory that provides a microscopic structure at the horizon scale. The originality of Andrea Puhm's research proposal is what earned her the ERC Starting Grant.
About the European Research Council Starting Grants
Starting Grants support early-career promising and talented scientists, with a proven track record or who have demonstrated the potential to become research leaders and who wish to form their own research team. Winners are provided with funding of up to € 1.5 million over a period of five years.
Find out more