Leonard Susskind and Pierre Sikivie have been awarded the 2025 Galileo Galilei Medal “for their work representing humanity’s persistent efforts to see and understand what may seem invisible, revealing in the process deep connections between the largest and smallest scales of Nature.” The medal was presented at Villa Galileo in Florence on 17 July 2025 (GGI award page; INFN press release).
An FQxI member and Felix Bloch Professor at Stanford, Susskind is recognized for his work on black holes and quantum gravity. The award committee highlights his “fundamental contributions to the study of quantum aspects of black holes,” and the deep links he has forged between particle physics, quantum information and complexity (GGI).
Historically, Susskind helped cement the holographic principle, building on Gerard ’t Hooft’s insight that information in a volume can be encoded on its boundary, an idea that became concrete with AdS/CFT and now underpins many modern approaches to the black-hole information paradox. ’t Hooft later cautioned that the holographic principle was often used in ways he hadn’t intended. For background and FQxI context on holography, see “The Holographic Universe”.
Susskind also pushed the frontier by tying entanglement to spacetime geometry. With Juan Maldacena he proposed ER = EPR, the conjecture that entangled systems are linked by non-traversable wormholes (arXiv:1306.0533), offering a new perspective on black-hole interiors and firewall puzzles (see FQxI’s podcast segment on “Detecting Black Hole Firewalls”). In later work, he argued that a black hole’s interior growth tracks the quantum complexity of its state and posited a “second law of complexity.”
“I have always admired Galileo Galilei for the way that he was able to draw the most far reaching and profound conclusions from the simplest ideas. In that regard, he was similar to Albert Einstein,” says Susskind. “It is wonderful to be honored with the Medal bearing his name.” (GGI)
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Image credit: INFN press release