[HN Gopher] Michael Rabin has died
       ___________________________________________________________________
        
       Michael Rabin has died
        
       Author : tkhattra
       Score  : 370 points
       Date   : 2026-04-15 18:07 UTC (3 days ago)
        
 (HTM) web link (en.wikipedia.org)
 (TXT) w3m dump (en.wikipedia.org)
        
       | adrian_b wrote:
       | Michael O. Rabin had important contributions in many domains, but
       | from a practical point of view the most important are his
       | contributions to cryptography.
       | 
       | After Ralph Merkle, Whitfield Diffie and Martin Hellman, Michael
       | O. Rabin is the most important of the creators of public-key
       | cryptography.
       | 
       | The RSA team (Ron Rivest, Adi Shamir and Leonard Adleman) is
       | better known than Michael O. Rabin, but that is entirely due to
       | marketing and advertising, because they founded a successful
       | business.
       | 
       | In reality the RSA algorithm is superfluous and suboptimal. If
       | the RSA team had never discovered this algorithm, that would have
       | had a null impact on the practice of cryptography. Public-key
       | cryptography would have been developed equally well, because the
       | algorithms discovered by Merkle, Diffie, Hellman and Rabin are
       | necessary and sufficient.
       | 
       | On the other hand, while without the publications of RSA,
       | cryptography would have evolved pretty much in the same way,
       | without the publications of Michael O. Rabin from the late
       | seventies the development of public-key cryptography would have
       | been delayed by some years, until someone else would have made
       | the same discoveries.
       | 
       | Together with Ralph Merkle, Michael O. Rabin was the one who
       | discovered the need for secure cryptographic hash functions, i.e.
       | one-way hash functions, which are now critical for many
       | applications, including digital signatures. Thus Rabin is the one
       | who has shown how the previously proposed methods of digital
       | signing must be used in practice. For example, the original
       | signing algorithm proposed by RSA could trivially be broken and
       | it became secure only in the modified form described by Rabin,
       | i.e. with the use of a one-way hash function.
       | 
       | Originally, Merkle defined 2 conditions for one-way hash
       | functions, of resistance to first preimage attacks and second
       | preimage attacks, while Rabin defined 1 condition, of resistance
       | to collision attacks. Soon after that it was realized that all 3
       | conditions are mandatory, so the 2 definitions, of Merkle and of
       | Rabin, have been merged into the modern definition of such hash
       | functions.
       | 
       | Unfortunately, both Merkle and Rabin have overlooked a 4th
       | condition, of resistance to length extension attacks. This should
       | have always been included in the definition of secure hash
       | functions.
       | 
       | Because this 4th condition was omitted, the US Secure Hash
       | Algorithm Standards defined algorithms that lack this property,
       | which has forced many applications to use workarounds, like the
       | HMAC algorithm, which for many years have wasted time and energy
       | wherever encrypted communications were used, until more efficient
       | authentication methods have been standardized, which do not use
       | one-way hash functions, for instance GCM, which is today the most
       | frequently used authentication algorithm on the Internet.
        
         | Ar-Curunir wrote:
         | Nobody has hidden the history of contributions of Rabin to
         | cryptography or computer science.
         | 
         | He is a Turing Award winner.
        
         | jonstewart wrote:
         | I would argue that nondeterministic finite automata are both
         | more significant and more practical.
        
         | tptacek wrote:
         | They didn't really found a successful business. They founded a
         | middling business that didn't do much but license a patent
         | until Security Dynamics, a smart card company, bought them and
         | took over the name.
        
           | YZF wrote:
           | The story that I remember going around is that they each made
           | some millions of dollars. That was a lot of money at the time
           | for academics. I audited a cryptography course given by Adi
           | Shamir in the early 90's and you couldn't tell he was rich
           | though.
        
             | tptacek wrote:
             | I mean, I'm sure it turned out great for them, but their
             | reputation definitely isn't rooted in their business
             | acumen.
        
         | YZF wrote:
         | I think you're vastly underplaying the importance of RSA to
         | cryptography. Personally it was the first time I was exposed to
         | the concept of public key cryptography (in the 1980's). "would
         | have been delayed by some years" is very dismissive. The same
         | thing can be said of many inventions. Yet someone is/was the
         | inventor.
         | 
         | RSA were the first to provide a practical and easy to
         | understand implementation and that had a huge impact in
         | practice.
         | 
         | That's not to downplay Rabin's or others contribution. That RSA
         | pursued a certain commercial strategy that you may or may not
         | like is not really relevant.
        
       | thraxil wrote:
       | I took his Introduction to Cryptography class when he was a
       | visiting professor at Columbia. Absolute master of an old-school
       | chalkboard lecturer. They don't make them like that any more.
        
         | medina wrote:
         | Hugely engaging, the margins of my notebook had many of his
         | quips... there was an archive online somewhere.
         | 
         | e.g., x minus x is zero, even for Euler, so therefore...
         | 
         | Found on Archive,
         | https://web.archive.org/web/20210509160248/http://www.eecs.h...
        
         | arbuge wrote:
         | I know him from Harvard and came here to say pretty much the
         | same thing. RIP.
        
           | ishi wrote:
           | I took his Computability class in the Hebrew University. He
           | got angry that students were often late to class, and said
           | that this never happened in Harvard...
        
             | ignoramous wrote:
             | Any of his "chalkboard" lectures (preferably in English) in
             | open archives of these universities? YouTube searches only
             | bring up Prof Rabin's lectures aided by slides and
             | presentation (ex:
             | https://www.youtube.com/watch?v=thK_qJqx5mo at Tel Aviv Uni
             | / https://www.youtube.com/watch?v=QCX0Ut0hcWw at Harvard).
        
               | YZF wrote:
               | There's a chalkboard here (used ~44:50):
               | 
               | Cryptography and Preventing Collusion in Second Price
               | (Vickery) Auctions - Michael Rabin
               | 
               | https://www.youtube.com/watch?v=4cmCBVrVQqc
               | 
               | No chalkboard but more lectures
               | 
               | https://youtu.be/nbePExzSTQ0?si=KkTbwfwj5rMtQUhD&t=681 -
               | ply tvrt hhtspnvt vyyshvmyh lthlykym pynnsyym (The
               | wonders of cryptography and financial applications)
               | 
               | https://www.youtube.com/watch?v=N_LG5Hcc8mM - Lecture 7 -
               | Zero Knowledge Proofs and Applications Michael Rabin
               | 
               | For those interested in searching for more here's a
               | Hebrew search string you can use: "prvpsvr mykl rbyn
               | hrtsh" interesting enough Google and YT search yield
               | results in English and Hebrew but possibly different ones
               | than just searching in English.
               | 
               | EDIT: One more:
               | 
               | https://www.youtube.com/watch?v=30wkb46BE1k
        
       | opem wrote:
       | It's hard to imagine how a single person managed to accomplish so
       | much. RIP to the great soul :|
        
         | tclancy wrote:
         | Seriously. After reading, I scrolled through his Known For
         | section and thought, "Alright already, leave something for
         | everybody else to work on."
        
       | puttycat wrote:
       | @dang this deserves a black ribbon
        
         | d-cc wrote:
         | What is a black ribbon?
        
           | vardump wrote:
           | Probably meant black HN top bar.
        
           | dredmorbius wrote:
           | An HN website tweak as a sign of respect on the passing of
           | notable contributors to the tech world:
           | 
           | <https://blog.willmeye.rs/whos-received-a-black-bar/>
        
         | wk_end wrote:
         | "@dang" doesn't do anything last I heard (though at this point
         | it's used often enough that maybe the HN folks should consider
         | it). If you want to reach the mods you can contact
         | hn@ycombinator.com I believe.
        
           | eranation wrote:
           | I did.
        
       | snitty wrote:
       | May his memory be a blessing.
        
       | AlecBG wrote:
       | First sentence starts with horrible antisemitism. Can someone fix
       | it? (on my phone with kids so not in a position to)
        
         | codingrightnow wrote:
         | It's been fixed.
        
           | fakedang wrote:
           | Still up. Looks like this is going to be another game of hit
           | the hedgehog.
        
             | metmac wrote:
             | People keep adding different slurs. Awful and disgraceful.
        
               | riddlemethat wrote:
               | Anti-Jew rhetoric is at a level unseen since WW2. It's
               | the new normal. It's horrible.
        
               | dbwkdofpqndjflf wrote:
               | Yeah, I come into contact with some form of Jewish hate
               | on a literal daily basis now. It's been this way for
               | months.
        
               | nothrabannosir wrote:
               | *It's the old normal :(
        
               | lambda wrote:
               | The article has now been been semi-protected to prevent
               | vandalism by anonymous users.
        
             | prmoustache wrote:
             | I had a look at the history of todays edits and it is
             | appalling.
        
               | redwood wrote:
               | Indeed I just figured out how to view them. Wow. https://
               | en.wikipedia.org/w/index.php?title=Michael_O._Rabin&...
        
             | zerocrates wrote:
             | An admin has now semi-protected the article.
        
           | welldoneator wrote:
           | Thank you! I'm a casual user of Wikipedia but after this
           | thread I went through the history of edits on the article
           | and...oh my.
           | 
           | I have a greater appreciation for folks like you and the
           | other editors who seem to be constantly removing this type of
           | stuf. Some truly horrendous slurs there.
        
         | harel wrote:
         | I used to regularly donate to the wikimedia foundation every
         | year. I stopped doing that as I find the whole project is now a
         | political tool and cannot be relied on. Even ignoring vandalism
         | like here, sometimtes the same articles get different meanings
         | depending on the language you view them in.
        
           | zozbot234 wrote:
           | Different language editions of Wikipedia are completely
           | different projects, with distinct user bases. You're never
           | looking at the "same" article across languages.
        
             | harel wrote:
             | In that case, Wikipedia should not link to them (and even
             | distance themselves from the edition) if they purposefully
             | change the content of the article to suit a political
             | agenda. The whole thing became a death match arena of
             | factions as mature as 12 year old kids playing an actual
             | death match arena game... This example here just
             | demonstrates my point.
        
         | blovescoffee wrote:
         | Wikipedia has demonstrably been ravaged by anti-semitism. Feel
         | free to ignore any of the notes here about Israel / anti-
         | Israeli sentiment which I understand is not clear cut. There's
         | demonstrably antisemitic coalitions editing wikipedia en-masse.
         | 
         | https://www.adl.org/resources/report/editing-hate-how-anti-i...
        
           | ogogmad wrote:
           | The ADL labels all opponents of Israel as anti-semitic. They
           | don't speak for Jewish people. Their smears help Israel by
           | hurting Jews, so that Zionists can point to Israel as their
           | only refuge. Helping Israel in turn hurts countless other
           | people who are not Jewish, which Zionists mostly don't care
           | about because Zionists are mostly ethno-centric, full of
           | self-pity, regurgitate predictable lies about Israel's
           | history without doing any critical investigation of their
           | own, and have absolutely no principles. You are amplifying
           | this.
           | 
           | I know this because I've grown up around them. I used to be
           | on their side until I found out that they lied to me about
           | certain events - and to such a degree that they swapped
           | around victim and perpetrator. They told me that the Gazans
           | blew up greenhouses when the Israeli settlers left, because
           | of their insane hatred of Jews. _Then_ I found out that the
           | only people who blew up any greenhouses were the Israeli
           | settlers - and that there was even a website set up solely to
           | rebut the claim that the Gazans did it. Then I found out that
           | Zionists didn 't care, because of a long litany of grievances
           | that had nothing to do with Palestinians. Then most of them
           | voted for a government that put Ben Gvir in charge of the
           | police force and prisons. Then they passed on a chance to use
           | diplomatic pressure to get Hamas to step down after the 07/10
           | attack, without launching a vengeful massacre in Gaza.
        
       | XCSme wrote:
       | I loved implementing the Rabin-Karp algoritm, such a fun and
       | celever solution.
        
       | maxtaco wrote:
       | Amazing man, with many important contributions over a very long
       | career. The Rabin Cryptosystem (like RSA, but with public
       | exponent 2) is notable for two reasons. First, unlike RSA, it is
       | provably as hard as "factorization" (as he would call it), and
       | second, unlike RSA, it wasn't protected by patent.
        
       | xorvoid wrote:
       | Thank you Michael Rabin for your excellent work. Rest in Peace.
       | 
       | Rabin Fingerprinting is one of my favorites of his contributions.
       | It's a "rolling hash" that allows you to quickly compute a 32-bit
       | (or larger) hash at *every* byte offset of a file. It is used
       | most notably to do file block matching/deduplication when those
       | matching blocks can be at any offset. It's tragically
       | underappreciated.
       | 
       | I've been meaning to write up a tutorial as part of my Galois
       | Field series. Someday..
       | 
       | Thank you again!
        
         | jonhohle wrote:
         | I recently found his fingerprint algorithm and wrote a utility
         | that uses it to find duplicate MIPS code for decompilation[0]
         | and build unique identifiers that can be used to find
         | duplicates without sharing any potentially copyrighted data[1].
         | 
         | This replaced some O(n2) searches through ASCII text, reducing
         | search time from dozens of seconds to fractions of a second.
         | 
         | 0 - https://github.com/ttkb-oss/mipsmatch 1 -
         | https://github.com/ttkb-oss/mipsmatch/wiki/Identifiers
        
         | __MatrixMan__ wrote:
         | I'm working on a data annotation system based around Rabin
         | fingerprints. They're a really neat idea.
         | 
         | I especially like how if you end up with hash characteristics
         | that you don't like, your can just select a different
         | irreducible Galois polynomial and now you've got a whole new
         | hash algorithm. It's like tuning to a different frequency.
         | 
         | For me it means I don't have to worry about cases where there
         | aren't enough nearby fingerprints for the annotation to adhere
         | to, I can just add or remove polynomials until I get a good
         | density.
        
         | vlovich123 wrote:
         | Important to note that FastCDC is about an order of magnitude
         | for block deduplication and is generally considered the state
         | of art for such an approach (speed of computing the hash is
         | more important than absolutely optimal distribution of hashes).
        
       | sidcool wrote:
       | Doctoral advisor - Alonzo Church
        
         | eranation wrote:
         | TIL. Also just realized that Alan Turing was also one of
         | Church's doctoral students. We stand on the shoulders of these
         | giants.
        
       | moralestapia wrote:
       | _" As a young boy, he was very interested in mathematics and his
       | father sent him to the best high school in Haifa, where he
       | studied under mathematician Elisha Netanyahu, who was then a high
       | school teacher."_
       | 
       | Interesting. Some people are lucky enough to find their vocation
       | quite early in life.
        
         | redwood wrote:
         | Wow hadn't heard of him
         | https://en.wikipedia.org/wiki/Elisha_Netanyahu
        
           | moralestapia wrote:
           | Yeah.
           | 
           | Everything is intertwined at some level.
           | 
           | Interesting.
        
           | myth_drannon wrote:
           | What a small world. But the entire extended family are
           | professors. Too bad one became a politician.
        
             | keybored wrote:
             | Benzion?
             | 
             | > Benzion Netanyahu ... A scholar of Judaic history, he was
             | also an activist in the Revisionist Zionism movement, who
             | lobbied in the United States to support the creation of the
             | Jewish state.
        
               | beagle3 wrote:
               | Benzion's son (and Elisha's nephew) Benjamin Netanyahu is
               | the Israeli prime minister.
        
               | keybored wrote:
               | Then there are at least two.
        
         | nephihaha wrote:
         | That's Benjamin Netanyahu's brother apparently.
         | 
         | Sad that the only thing that shows up nowadays in searches
         | tends to be Wikipedia. I miss the democratic internet with lots
         | of quirky sites you could find with ease.
        
           | jojomodding wrote:
           | actually his uncle.
        
       | ontouchstart wrote:
       | Michael Rabin, 1976 ACM Turing Award Recipient
       | 
       | https://youtu.be/L3FZzGU3n14
        
         | seism wrote:
         | That sly remark at 22:40 on the telephone ringing :)
        
       | peterbonney wrote:
       | I had the incredible good fortune to take one of his classes in
       | college, and I loved it so much I took another just to learn from
       | him again. A tremendous intellect AND an incredibly engaging and
       | talented instructor. It would be an exaggeration to say that I
       | knew him, but nevertheless he had a great impact on my education
       | and my life. He will be missed.
        
       | BrianneLee011 wrote:
       | A founding father of computer science has passed away. Thank you
       | for building the foundations that made modern AI possible.
        
       | gchallen wrote:
       | I took a course from him as a graduate student. I was not (and am
       | still not) a theoretician. But I enjoyed the class and Professor
       | Rabin's lectures.
       | 
       | A friend of mine was one of his graduate students and a teaching
       | assistant for the class. He pointed out to me once that Professor
       | Rabin would state many of his points during lecture twice. Once I
       | started listening more carefully, I found this to be true. It was
       | both subtle and pedagogically effective.
       | 
       | English was not his first language, but he enjoyed his struggles
       | with it. I remember him stumbling over the pronunciation of a
       | word during class. Giving up with a smile, he said, "This is a
       | word I know only from books."
        
       ___________________________________________________________________
       (page generated 2026-04-18 23:00 UTC)