Leonard Adleman

University of Southern California

Leonard Max Adleman is an American computer scientist at USC who, together with Ron Rivest and Adi Shamir, invented the RSA public-key cryptosystem in 1977, the foundation of modern secure communications. Adleman contributed the mathematical rigor — particularly the proof that RSA's security rests on the hardness of factoring large integers — and the system's formal analysis. In 1994, he pioneered DNA computing by demonstrating that biological molecules could solve a combinatorial optimization problem (the Hamiltonian path problem on a small graph) through massively parallel biochemical operations, founding an entirely new paradigm for computation. This work showed that DNA strands could encode and process information, opening research directions in biological computation and molecular information storage. Adleman received the 2002 ACM Turing Award together with Rivest and Shamir. He has also contributed foundational work in the theory of computer viruses and has written memoirs about the birth of RSA and DNA computing that are widely read in the computer science community.