Shafi Goldwasser

Background

Shafi Goldwasser, born Shafrira Goldwasser on November 14, 1959, in New York City, is an American-Israeli computer scientist known for her foundational contributions to modern cryptography and computational complexity theory. She earned a B.S. in mathematics and science from Carnegie Mellon University in 1979, followed by an M.S. (1981) and Ph.D. (1984) in computer science from the University of California, Berkeley, where she was advised by Manuel Blum.

Probabilistic Encryption

In 1982, Goldwasser began a collaboration with fellow Berkeley graduate student Silvio Micali that would reshape cryptography. Their 1984 paper "Probabilistic Encryption," published in the Journal of Computer and Systems Sciences, introduced the first encryption scheme that was provably secure under a precise mathematical definition, now known as semantic security. Unlike earlier deterministic schemes, probabilistic encryption ensures that a single plaintext can map to many different ciphertexts, preventing an adversary from learning partial information about a message even when given access to the ciphertext. This work produced the Goldwasser-Micali cryptosystem, whose security rests on the hardness of the quadratic residuosity problem.

Zero-Knowledge Proofs

In 1985, Goldwasser, Micali, and Charles Rackoff introduced the concept of zero-knowledge proofs in their paper "The Knowledge Complexity of Interactive Proof-Systems." The paper formalized how one party (a prover) could convince another (a verifier) that a statement is true without revealing any information beyond the fact that the statement is true. The authors demonstrated the first zero-knowledge proof for a concrete number-theoretic problem, deciding quadratic nonresiduosity modulo a composite number. This work, along with related contributions on interactive proof systems by Laszlo Babai and Shlomo Moran, earned all five researchers the inaugural Godel Prize in 1993. Zero-knowledge proofs later became a cornerstone of privacy-preserving authentication, secure multiparty computation, and blockchain technologies.

Academic Career

Goldwasser joined the faculty of the Massachusetts Institute of Technology in 1983 and became the first holder of the RSA Professorship of Electrical Engineering and Computer Science there in 1997. Since 1993 she has also held a concurrent professorship at the Weizmann Institute of Science in Israel. Beyond her founding work in cryptography, she made significant contributions to computational complexity theory, including work on interactive proof systems and their connections to hardness of approximation, and to the theory of pseudorandom functions. In January 2018 she became director of the Simons Institute for the Theory of Computing at the University of California, Berkeley, a position she held through August 2024. In November 2016 she co-founded Duality Technologies, a company applying homomorphic encryption to privacy-preserving data analytics, where she serves as chief scientist.

Turing Award and Recognition

In 2012, Goldwasser and Silvio Micali were jointly awarded the ACM A.M. Turing Award, computing's highest honor, "for transformative work that laid the complexity-theoretic foundations for the science of cryptography, and in the process pioneered new methods for efficient verification of mathematical proofs in complexity theory." This was in addition to two Godel Prizes (1993 and 2001), the ACM Grace Murray Hopper Award (1996), the RSA Award in Mathematics (1998), the IEEE Emanuel R. Piore Award (2011), and election to the National Academy of Sciences (2004) and the National Academy of Engineering (2005), among other honors.

Legacy

Goldwasser's research established the modern paradigm of defining security goals precisely and proving that cryptographic constructions meet them, replacing ad hoc heuristic designs with rigorous mathematical guarantees. Her work with Micali and Rackoff on zero-knowledge proofs and interactive proof systems opened entire subfields of theoretical computer science and remains central to contemporary applications in secure computation, digital identity, and blockchain protocols.

Timeline

• 1959-11-14Born in New York City.
• 1979Earns B.S. in mathematics and science from Carnegie Mellon University.
• 1984Earns Ph.D. in computer science from UC Berkeley, advised by Manuel Blum.
• 1984Publishes "Probabilistic Encryption" with Silvio Micali, introducing semantically secure encryption and the Goldwasser-Micali cryptosystem.
• 1985Co-authors "The Knowledge Complexity of Interactive Proof-Systems" with Silvio Micali and Charles Rackoff, introducing zero-knowledge proofs.
• 1983Joins the faculty of the Massachusetts Institute of Technology.
• 1993Receives the inaugural Godel Prize (with Micali, Rackoff, Babai, and Moran) for work on interactive proof systems; begins concurrent professorship at the Weizmann Institute of Science.
• 1996Receives the ACM Grace Murray Hopper Award.
• 1997Becomes the first holder of the RSA Professorship of Electrical Engineering and Computer Science at MIT.
• 2001Receives a second Godel Prize.
• 2004Elected to the National Academy of Sciences.
• 2012Receives the ACM A.M. Turing Award jointly with Silvio Micali for foundational work in cryptography and complexity theory.
• 2016-11Co-founds Duality Technologies as chief scientist.
• 2018-01Becomes director of the Simons Institute for the Theory of Computing at UC Berkeley.