An electrical engineer who develops quantum-computing hardware.^[ref]

Paul E. McKenney is a computer scientist known for work on concurrent computing and operating-system kernels. His contributions include read-copy-update, developed for systems in which reads are frequent and updates must coexist with them.^[ref]

The key read-copy-update distinction is between removing an object from a shared data structure and reclaiming its storage. An earlier reader may still hold a reference after removal; reclamation waits until the relevant readers have finished. That separation permits lighter synchronization on the read path. It is an example of how the lifetime of a shared object becomes part of a concurrent algorithm.^[ref]

With David Howells, he also authored the kernel guide to circular buffers and their memory barriers.^[ref]

Tony Hoare is a computer scientist whose contributions include quicksort, Hoare logic and communicating sequential processes. His industrial work included an early ALGOL 60 compiler; his institutional biography also describes an unsuccessful operating system project, giving concrete context for the difficulty of reliable systems engineering.^[ref]

In his 1969 paper An Axiomatic Basis for Computer Programming by Tony Hoare, he set out assignment, composition and iteration rules for reasoning directly about program text. The assignment rule reasons backward from the required result, while a loop invariant compresses arbitrarily many iterations into a preservation obligation. The paper explicitly distinguishes these partial correctness results from successful termination and discusses how arithmetic and side effects affect the model.^[ref]

Scott Kirkpatrick is a computer scientist whose work connects statistical physics with computational complexity theory and optimization. With Charles Daniel Gelatt Jr. and Mario P. Vecchi, he developed simulated annealing as a method for combinatorial optimization.^[ref]

The method borrows a rule from the Metropolis algorithm: a proposed increase $\Delta C>0$ in cost can be accepted with probability $\exp (-\Delta C/T)$, where $T$ is an adjustable control parameter in the same units as the cost. Allowing occasional uphill changes can escape a local minimum; reducing $T$ progressively makes them less likely. The original work applied this physical analogy to electronic component placement and wiring.^[ref]

Robert Tarjan is a computer scientist whose work connects efficient graph algorithms, data structures and rigorous analysis. His contributions include algorithms for lowest common ancestors and, with collaborators, splay trees and Fibonacci heaps.^[ref]

His work on amortized analysis explains why an individual operation can be expensive while a whole sequence remains efficient. The accounting assigns the cost of occasional restructuring across the sequence instead of assuming each operation has the same worst-case cost. Splay trees make this distinction particularly concrete: moving recently accessed nodes changes the tree while supporting strong bounds over a sequence of accesses.^[ref]

Homepage: www.cs.princeton.edu/~ret/

Institutional profile: www.hertzfoundation.org/people/robert-tarjan/

Gerald Jay Sussman is a computer scientist whose work includes the design and explanation of systems expressed as programs. With Hal Abelson and Julie Sussman, he authored Structure and Interpretation of Computer Programs by Harold Abelson and others, a text that develops programming abstraction, recursion and models of program execution through Scheme.^[ref]

One useful distinction in the text is between the shape of a procedure's source and the computation it generates. A syntactically recursive procedure can produce an iterative process when no deferred operations accumulate. That makes the execution model, rather than the presence of a self-call alone, central to reasoning about storage.^[ref]

Biography: www.csail.mit.edu/person/gerald-sussman

Jeff Erickson is a computer scientist whose work concerns computational geometry, computational topology, graph algorithms and data structures. His research also examines how students learn to design algorithms.^[ref]

His open textbook Algorithms by Jeff Erickson develops algorithm design through explicit examples, proofs and analysis. Its treatments of dynamic programming and depth-first search show complementary organizing ideas: reuse results of smaller subproblems, or explore the structure of a graph. The explanations connect the procedure with the invariant or recurrence that justifies it.^[ref]

Homepage: jeffe.cs.illinois.edu/

Venkatesan Guruswami is a computer scientist whose research includes coding theory, computational complexity theory, pseudorandomness and the complexity of approximate optimization. A major focus is list decoding of error-correcting codes.^[ref]

Ordinary unique decoding aims to recover one transmitted message; list decoding permits a bounded list of candidate messages when the received word has too many errors for uniqueness. The resulting questions connect the amount of redundancy in a error-correcting code with how much corruption can be handled efficiently. His research profile also describes work on approximate solutions to problems with NP-hardness.^[ref]

Identity source: theory.cs.berkeley.edu/

Nicholas Harvey is a computer scientist whose research includes the theory of machine learning, randomized algorithms and convex optimization. His teaching work includes a draft text on randomized algorithms, with separate undergraduate and graduate volumes.^[ref]

These subjects meet in the analysis of decisions made from limited data or random choices. A randomized algorithm specifies both a computational procedure and a distribution over its choices; its analysis can bound expected work or the chance of an incorrect result. Keeping those guarantees distinct is central to understanding what randomness contributes.

Identity source: www.cs.ubc.ca/~nickhar/W12/

Valentine Kabanets is a computer scientist whose research concerns computational complexity theory, derandomization, pseudorandomness and circuit complexity. A recurring question in his research is when efficient randomized algorithms can be replaced by efficient deterministic algorithms.^[ref]

His research description emphasizes a connection between designing fast algorithms and proving circuit lower bounds. An upper bound supplies an efficient method for a problem; a lower bound rules out methods within a specified model. In some settings, progress on one side can imply progress on the other, turning apparent obstacles into tools.^[ref]

Identity source: www2.cs.sfu.ca/~kabanets/

A computer scientist researching adaptive and distributed computing.^[ref]

Fritz Strassmann worked with Otto Hahn on chemical identification of the products formed when neutrons irradiate uranium. In December 1938 their separation and analytical methods identified radioactive barium products. This chemical evidence was a crucial step toward the explanation of nuclear fission by Lise Meitner and Otto Frisch.^[ref]

A chemist.^[ref]

Otto Hahn and Fritz Strassmann identified radioactive barium among the products of uranium irradiation by neutrons in December 1938. Their chemical separation and analysis established a surprising light-element product. Lise Meitner and Otto Frisch then explained the result in terms of nuclear fission.^[ref]

A chemist.^[ref]

Alan D. McNaught coauthored research on carbohydrate.^[ref]

Carbohydrates are a family of chemical substances encompassing monosaccharides, combinations of monosaccharides, and their derivatives. Glucose is a small carbohydrate; cellulose is a long-chain polysaccharide. Deoxyribose illustrates why composition alone does not define the family: replacing a hydroxy group in ribose by hydrogen still leaves a carbohydrate. See IUPAC Gold Book: carbohydrates.

François-Marie Raoult is associated with quantitative relations between chemical solution composition and physical properties. Raoult's law relates a component's partial vapor pressure in an ideal liquid mixture to its mole fraction and the pure component's vapor pressure at the same temperature. It provides a reference model against which nonideal solution behaviour can be compared.^[ref]

Chemist.

Biographical sketch: www2.chem.umd.edu/thermobook/v10-screen.pdf

Irving Langmuir investigated gas adsorption on solid surfaces. The Langmuir adsorption model treats a surface as a set of sites that can each be empty or occupied, balancing adsorption against desorption.

The finite number of sites produces saturation: increasing gas pressure cannot raise single-layer occupancy above one molecule per site in this model. Lateral interactions and multilayer formation require a different description.^[ref]

A chemist working on physical chemistry.

Biographical archive: tile.loc.gov/storage-services/service/gdc/gdcfindingaidpdfs/ms012160/ms012160.pdf

Anne Erwin Moody developed approaches to teaching chemistry that joined chemical safety with scientific ethics. A coauthored 1999 paper describes using readings and case studies to examine decisions about personal safety, honesty, and integrity in chemical work. It treats these decisions as skills that students can practice through discussion.^[ref]

A chemist identified as Professor Emerita of Chemistry in Truman State University’s May 2026 commencement programme.

University programme: www.truman.edu/wp-content/uploads/2026/05/MayCommencementProgram-2026-WEB.pdf

Stephen F. Mason investigated optical activity and molecular dissymmetry in coordination chemistry. His account distinguishes different refractive indices for opposite circular polarizations from unequal absorption of those polarizations.

The first produces circular birefringence and the second circular dichroism. They probe related aspects of a chiral material through different experimental observables.^[ref]

A chemist who studied optical activity.

Royal Society of Chemistry obituary: www.rsc.org/news/obituaries/emeritus-professor-stephen-mason-cchem-frsc-frs

Germain Henri Hess studied heat changes accompanying chemical reactions. Hess's law expresses the additivity of compatible reaction enthalpies: reversing a reaction reverses the sign, and combining reaction equations combines their enthalpy changes. This makes it possible to obtain an otherwise inaccessible heat change from an enthalpy cycle.^[ref]

A chemist who studied energy changes during chemical reactions; Hess's law bears his name.

Royal Society of Chemistry biographical notice: edu.rsc.org/resources/on-this-day-aug-08--henri-hess-was-born/10808.article

Mary Jane Simpson authored a quantitative teaching experiment on coloured drink solutions. A water blank, an absorption-peak scan, and serial dilutions connect absorbance with concentration.

The experiment separates visual colour comparison from an instrumental measurement. Quantitative transfer and final-volume calibration matter because dilution ratios are part of the inferred chemical amount.^[ref]