Vera Fischer is a Brazilian mathematician known for her work in the field of mathematics, particularly in algebra and geometry. She has made significant contributions to various areas of mathematical research and has been involved in academia, including positions at universities and institutions where she teaches and conducts research. Additionally, Fischer has been recognized for her efforts to promote mathematics and education in Brazil.

Wojciech Samotij is a mathematician noted for his work in the fields of combinatorics and graph theory. He is particularly recognized for his contributions to various problems and results in these areas, often focusing on themes like extremal combinatorics, which studies how large a combinatorial structure can be while avoiding certain substructures.

Ars Mathematica Contemporanea is a scientific journal that publishes research articles in the field of mathematics. It aims to provide a platform for the dissemination of high-quality research across various areas of mathematics, including but not limited to pure mathematics, applied mathematics, and mathematical applications in other scientific fields. The journal emphasizes contemporary issues and advancements in mathematical research, and it typically features peer-reviewed articles to ensure the integrity and quality of the published work.

A Davenport–Schinzel sequence is a specific type of sequence formed by applying certain restrictions on the allowable subsequences. Named after mathematicians H. Davenport and A. Schinzel, these sequences arise in the context of combinatorial geometry and computational geometry. In a Davenport–Schinzel sequence, the sequences consist of elements drawn from a finite set, typically called the alphabet set, subject to specific constraints.

The term "random group" can refer to various concepts depending on the context in which it is used. Here are a few interpretations: 1. **Statistics**: In research or survey methodologies, a random group may refer to a sample of individuals selected from a larger population in such a way that every individual has an equal chance of being chosen. This randomization helps to eliminate bias and ensures that the sample is representative of the population.

A **pandiagonal magic cube** is a three-dimensional extension of the concept of a magic square. In a magic square, the numbers in each row, column, and diagonal sum to the same constant (known as the magic constant). A pandiagonal magic square also requires that the sums of certain "broken" diagonals (diagonals that wrap around the edges of the square) equal the magic constant.

The term "broken space diagonal" typically refers to a type of path or line that moves at an angle through three-dimensional space but does not form a straight line. Instead of connecting two points directly, a broken space diagonal changes direction or has segments that connect the two endpoints through a series of straight-line segments.

An **almost ring** is a mathematical structure that generalizes the concept of a ring, with some relaxation of the usual axioms. In particular, an almost ring is defined by a set equipped with two operations (usually called addition and multiplication) that partially satisfy the properties of a ring, but do not necessarily satisfy all the ring axioms. In general, the concept of an almost ring can vary in definition depending on the context or the specific formulation found in various mathematical literature.

An Arf ring is a specific type of commutative ring in the field of algebra, particularly in the study of algebraic topology and homotopy theory. It is named after the mathematician Michael Arf, who contributed significantly to the theory of forms and associated structures.

In algebra, specifically in the theory of rings and modules, an *Artinian ideal* typically refers to an ideal in a ring that satisfies the descending chain condition (DCC). This means that any descending chain of ideals within an Artinian ideal eventually stabilizes; that is, there are no infinite descending sequences. More generally, a ring is called an *Artinian ring* if it satisfies the descending chain condition for ideals.

In algebra, the concept of **change of rings** involves the study of a ring homomorphism and how it allows us to transfer structures and properties from one ring to another. This is particularly relevant in areas like algebraic geometry, representation theory, and commutative algebra.

Constructible topology is a concept in the field of mathematical logic and set theory, particularly in the context of model theory and the foundations of mathematics. It is used to study the properties of sets and their relationships with various mathematical structures. In the constructible universe, denoted as \( L \), sets are built in a hierarchical manner using definable sets based on certain criteria.

In the context of commutative algebra and algebraic geometry, the dualizing module is an important concept that arises in the study of schemes and their cohomological properties. ### Definition Given a Noetherian ring \( R \), the dualizing module is an \( R \)-module \( \mathcal{D} \) that serves as a kind of "dual" object to the module of differentials.

A geometrically regular ring is a concept that arises in algebraic geometry and commutative algebra. Specifically, it relates to geometric properties of the spectrum of a ring, particularly in regard to its points and their corresponding field extensions.

A **principal ideal ring** (PIR) is a type of ring in which every ideal is a principal ideal. This means that for any ideal \( I \) in the ring \( R \), there exists an element \( r \in R \) such that \( I = (r) = \{ r \cdot a : a \in R \} \). In other words, each ideal can be generated by a single element.

In the context of ring theory in abstract algebra, a **seminormal ring** is a type of ring that satisfies certain conditions related to its elements and their relationships.

Neil Ashby may refer to different individuals depending on the context, but one well-known person by that name is a physicist recognized for his work in the field of astrophysics.