Author: Andrew Lowry
Andrew Lowry
Andrew Lowry, a corporate professional and Senior Editor at mahdi.cheraghchi.info, is engrossed in mathematics every minute of his free time. His interests are deeply rooted in theoretical computer science, coding theory, information theory, and cryptography; he approaches these subjects as someone who genuinely cannot stop thinking about them rather than as a casual observer. He is most likely reading a proof when he is not in a meeting.
There is a specific type of cryptography issue that subtly affects everything, from the encrypted whisper between two satellites to the chip in a bank card. That certainly applies to the work of Fuchun Lin and his associates. It’s not ostentatious. It doesn’t guarantee that the internet will be saved or broken. It fills in a gap that researchers have been focusing on for years: what happens when an adversary has the ability to both listen and tamper, rather than just one or the other. The majority of students studying coding theory are taught early on that an error correcting…
The way theoretical computer science keeps returning to issues that, on paper, appear to have been resolved decades ago is almost comical. That includes linear threshold predicates. A few variables, each of which is either +1 or −1, are multiplied by positive integer weights, added together, and the sign is verified. That’s all. the entire apparatus. However, an entire research community has discovered a problem that refuses to behave somewhere between the simplicity of that formula and the messy reality of approximating it. Mahdi Cheraghchi, Johan Håstad, Marcus Isaksson, and Ola Svensson’s 2012 paper, which started out as a RANDOM…
A theoretical computer science conference has an almost antiquated feel to it. People travel from all over the world, sit in hotel ballrooms with subpar coffee, and watch as others present proofs on slides that hardly anyone in the audience can follow in real time. That was precisely what happened at FOCS 2022, which took place in Denver from late October through early November. However, as the schedule developed over those four days, it was difficult not to sense that something real was taking place—a field recovering from two bizarre pandemic years and rediscovering what it truly looks like to…
Information theory and coding have a subtle stubbornness to them. It doesn’t follow any trends. It doesn’t receive eye-catching magazine covers. However, practically every digital moment of contemporary life depends on it in ways that most people won’t even be aware of. In a way, the five-day workshop in April 2018 at Harvard’s Center of Mathematical Sciences and Applications was a snapshot of that obstinacy; mathematicians, computer scientists, and information theorists came together to try to advance a field that has been pushing itself, largely unseen, for almost eight decades. That week, if you had entered 20 Garden Street, you…
At the heart of theoretical computer science, there is an unanswered question that is worth precisely one million dollars to the person who can answer it. It was included in the Millennium Prize Problems list by the Clay Mathematics Institute in 2000. It’s still open twenty-five years later. It is surprisingly easy to ask: Does P equal NP? Even though the solution would completely change cryptography, artificial intelligence, logistics, and the architecture of digital security, the majority of people are unaware of it because it takes a brief detour into computational complexity theory, a field that tends to remain hidden…
On a weekday afternoon, if you stroll south from Stanford’s main quad, past the eucalyptus shade and bicycle racks, you come to a building that exudes a sense of almost sinister confidence. Located at the intersection of Jane Stanford Way and Lomita Mall, the new Computing and Data Science building—simply referred to as CoDa on campus—behaves differently from the surrounding older sandstone arcades. Yes, it gives them a nod. The façade’s vertical terracotta panels are obviously intended to mimic the ancient core’s warm, earthy hues. However, another aspect of the geometry—something bent and detached—indicates that the building is not actually…
The way Jack Dennis spent his career has a subtle lyrical quality. He created graphs. Arrows link boxes, circles contain little operators, and lines indicate how a number could move from one calculation to the next. It could have appeared to anyone passing his MIT office in the late 1970s to be the doodling of a man who was too patient for his own good. It wasn’t. Even though the majority of engineers who use it today are unable to identify the original creator, those sketches went on to become one of the most important abstractions in contemporary computer science.…
Academic medicine is currently experiencing a subtle uneasiness that has nothing to do with hospital budgets or insurance codes. It has to do with memory, more especially the type of memory that machines aren’t meant to have. Together with partners at the Broad Institute, MIT researchers have begun to pull at a thread that the majority of the AI healthcare sector would presumably prefer to remain untangled. When the thread is pulled, an unsettling revelation emerges: the foundation models that hospitals are rushing to implement might subtly remember the individuals whose records taught them. FieldDetailsStudy TitlePrivacy Risks in Foundation Models…
The way cryptographers discuss non-malleability has an odd stillness about it, as though the concept itself defies simple explanation. At conferences, usually late in the day, you hear someone lean back and explain, almost grudgingly, that the true issue was not encryption but rather what an attacker could do with it once they had it. Compared to most beginner textbooks, that seems more accurate. ConceptNon-Malleable CryptographyFirst Formalized ByDolev, Dwork, and Naor (1991)Foundational Encryption SchemeNaor–Yung paradigm, later strengthened with non-malleable NIZKCore PropertyTampered ciphertexts cannot decrypt to a related plaintextPrimary Threat ModelAdaptive chosen-ciphertext attack (CCA2)Modern ExtensionContinuous non-malleable codes (Dziembowski et al., ICS’10…
Thirty years ago, a mathematician named Peter Shor produced a brief paper that subtly changed the course of history. At the time, the idea of creating a computer that followed the peculiar logic of quantum mechanics was a half-serious science curiosity. His algorithm accomplished something that no one could have predicted. It explained how arithmetic problems that would take billions of years for classical computers could be solved in a matter of hours by a quantum machine, assuming one ever existed. By historical coincidence, those issues were the ones supporting the entire digital trust architecture. SubjectQuantum Threat to Encryption —…