"a PhD level understanding of computer aided geometric design"

could you elaborate?

I found chatgpt to pretty useful in high level understanding of where the topics stand in the grand scheme of things

kinda like a pre-google -- it helps me navigate what to google

let's ask gpt4o

You're an expert math researcher.

- Give me an overview of topos theory
- What are the main unsolved problems
- What is the point of it?
- What research directions are most promising?
- What are the math prerequisites to understanding it?

output

Overview of Topos Theory

Topos theory is a branch of mathematics that generalizes set theory and category theory, providing a framework for analyzing and understanding mathematical structures. A topos can be seen as a generalized space that behaves much like the category of sets but with more flexible and abstract properties. Topos theory was developed by Alexander Grothendieck and his collaborators in the 1960s, initially to solve problems in algebraic geometry.

Key concepts in topos theory include:

Categories: Collections of objects and morphisms (arrows) between them.
Sheaves: Structures that systematically organize data over a topological space.
Topoi (plural of topos): Categories that satisfy certain axioms making them similar to the category of sets.

Main Unsolved Problems
Some of the main unsolved problems in topos theory involve:

Classifying all possible topoi: Understanding the full landscape of possible topoi and their interrelationships remains a complex challenge.
Connections to other areas of mathematics: Fully elucidating the connections between topos theory and other fields such as logic, algebraic geometry, and mathematical physics.
Homotopy theory in the context of topoi: Developing a deeper understanding of homotopy theory within the framework of higher topos theory.

The Point of Topos Theory
The point of topos theory is to provide a unifying and flexible framework for various mathematical concepts and structures. It offers a generalized setting in which both geometric and logical ideas can be expressed and related. This has significant implications for:

Algebraic geometry: Offering new tools and perspectives.
Mathematical logic: Providing a categorical framework for logic and set theory.
Theoretical computer science: Influencing the development of type theory and the semantics of programming languages.

Promising Research Directions
Some of the most promising research directions in topos theory include:

Higher Topos Theory: Extending the classical theory to higher categories and understanding its implications in algebraic geometry and homotopy theory.
Connections with Logic: Exploring further connections between topos theory and logic, particularly in relation to intuitionistic logic and type theory.
Topos-theoretic Approaches to Physics: Investigating how topos theory can be applied to quantum mechanics and other areas of theoretical physics.
Descent Theory and Stacks: Further developing the applications of topos theory in descent theory and the study of stacks in algebraic geometry.

Math Prerequisites to Understanding Topos Theory
To understand topos theory, one should have a solid background in the following areas:

Category Theory: Fundamental concepts such as categories, functors, natural transformations, limits, and colimits.
Set Theory: Basic set-theoretic concepts and operations.
Algebraic Topology: Basic knowledge of topological spaces, sheaves, and cohomology.
Algebra: Basic group theory, ring theory, and module theory.
Logic: Understanding of basic logical systems, particularly intuitionistic logic.
With these prerequisites, one can start delving into the more advanced and abstract concepts of topos theory.

not perfect but good enough to get started