👉 Dead math, also known as "dead theory" or "dead concepts," refers to mathematical ideas, theorems, or principles that are no longer actively used or considered relevant in current mathematical research and applications. These concepts often stem from historical developments or foundational theories that, while once central to mathematics, have been superseded by newer frameworks, computational advancements, or shifts in mathematical focus. For example, the rigorous foundations of calculus developed by Cauchy and Weierstrass in the 19th century, which replaced earlier intuitive or limit-based approaches, are now seen as foundational but not "dead" since they underpin much of modern analysis. Similarly, the use of complex numbers in solving polynomial equations, once a radical departure from real-number mathematics, is now ubiquitous. Dead math highlights the evolution of mathematical thought, showing how theories adapt or become obsolete as new tools and perspectives emerge, yet retaining value as historical milestones that shaped the discipline.
