In 1972, a 25 year old doctoral student at Princeton planted a time bomb in the foundations of modern physics. Jacob Bekenstein, working under the legendary John Wheeler, proposed that black holes possess entropy, a measurable quantity proportional to the area of their event horizons. It was a radical claim. It was also correct, and its consequences have tormented theoretical physics ever since.

Two years later, Bekenstein immigrated to Israel. He would spend the remaining four decades of his life there, first at Ben-Gurion University in the Negev, then at the Hebrew University of Jerusalem, building and defending the framework that made him one of the most consequential physicists of his generation.

Bekenstein’s insight meant that black holes are not featureless voids. They contain information, encoded on their surfaces in ways that obey the laws of thermodynamics. When Stephen Hawking built on this work and showed that black holes radiate energy and eventually evaporate, the problem became unavoidable. If a black hole disappears entirely, the information it contains appears to vanish with it. Quantum mechanics forbids this. Information, like energy, can be scrambled and redistributed but never destroyed. The seed of a paradox was planted at Princeton. Its full implications would be worked out, challenged, and defended from Jerusalem.

For over fifty years, physicists have proposed solutions. None has been........

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