The 19th century was a pivotal time for the development of physics, particularly in Britain, where several influential physicists made significant contributions to the field. Here are some notable 19th-century British physicists and their contributions: 1. **Michael Faraday (1791–1867)**: Often regarded as one of the most important experimentalists in the history of science, Faraday made substantial contributions to electromagnetism and electrochemistry.

The term "2020s in computing" refers to the trends, developments, technologies, and impactful events in the field of computing during the 2020s decade, which began in January 2020. Here are some key themes and advancements that have characterized this period: 1. **Artificial Intelligence and Machine Learning**: AI and ML continue to advance rapidly, with applications in various fields such as healthcare, finance, transportation, and entertainment.

The term “21st-century American physicists” refers to physicists who are active and making significant contributions to the field of physics in the United States during the 21st century, specifically since the year 2001. This period has seen numerous advancements in various areas of physics, including particle physics, astrophysics, condensed matter physics, and quantum mechanics. Key areas of focus among 21st-century physicists in the U.S.

The term "21st-century Chinese physicists" refers to the numerous prominent physicists from China who have made significant contributions to various fields of physics during the 21st century. China's investments in science and technology have led to a surge in research output and a growing presence in the global scientific community.

A commutator is a mathematical concept that appears in various fields such as group theory, linear algebra, and quantum mechanics. Its specific meaning can vary depending on the context.

The inverse limit (or projective limit) is a concept in topology and abstract algebra that generalizes the notion of taking a limit of sequences or families of objects. It is particularly useful in the study of topological spaces, algebraic structures, and their relationships.

A glossary of group theory includes key terms, definitions, and concepts that are fundamental to understanding group theory, a branch of abstract algebra. Here are some essential terms and their meanings: 1. **Group**: A set \( G \) equipped with a binary operation \( \cdot \) that satisfies four properties: closure, associativity, identity element, and invertibility.

Room acoustics is the study of how sound behaves in an enclosed space. It encompasses the interactions of sound waves with the surfaces of the room—such as walls, ceilings, and floors—as well as furniture and other objects. The goal of understanding room acoustics is to influence the auditory experience within that space, whether for music, speech, or other sound sources.

"Live at the Sydney Opera House" is a live album by Australian singer-songwriter Josh Pyke, released in 2014. The album captures Pyke's performance at the iconic Sydney Opera House, showcasing his distinctive acoustic sound and storytelling ability. The recording features a mix of his popular songs along with a few anecdotes and interactions with the audience, creating an intimate concert experience.

A lattice word is a concept primarily used in the fields of combinatorics and formal language theory. It refers to a specific arrangement of symbols that can be visualized as a word in a lattice structure. In more technical terms, a lattice word typically arises when considering combinatorial objects associated with lattice paths. In a combinatorial context, a common interpretation of lattice words involves considering strings that correspond to paths on a grid.

An Abelian integral is a type of integral that is associated with Abelian functions, which are a generalization of elliptic functions. Specifically, Abelian integrals are defined in the context of algebraic functions and can be represented in the form of integrals of differentials over certain paths or curves in a complex space.

A real hyperelliptic curve is a specific type of algebraic curve that generalizes the notion of elliptic curves to a higher genus.

A parabola is a type of conic section defined as the set of all points in a plane that are equidistant from a fixed point called the focus and a fixed line called the directrix. Parabolas have a characteristic U-shaped curve and can open either upwards, downwards, left, or right, depending on their orientation.

A singular point of a curve refers to a point on the curve where the curve fails to be well-behaved in some way. Specifically, a singular point is typically where the curve does not have a well-defined tangent, which can occur for a variety of reasons. The most common forms of singular points include: 1. **Cusp**: A point where the curve meets itself but does not have a unique tangent direction. There might be a sharp turn at the cusp.

In algebraic topology, a **chain** refers to a formal sum of simplices (or other geometric objects) that is used to construct algebraic invariants of topological spaces, typically within the framework of **singular homology** or **simplicial homology**. ### Key Concepts: 1. **Simplicial Complex**: A simplicial complex is a collection of vertices, edges, triangles, and higher-dimensional simplices that are glued together in a specific way.

A Seidel adjacency matrix is a type of matrix used in graph theory, particularly for the representation of certain types of graphs known as Seidel graphs. It is derived from the standard adjacency matrix of a graph but has a distinctive form.