What is the difference between 数学 and 数理?


I noticed that both terms referred to the study of mathematics. Is there a
difference in usage between the two terms?




数学 is (pure) mathematics.

数理 refers to [mathematical
sciences](https://en.wikipedia.org/wiki/Mathematical_sciences), "group of
areas of study that includes, in addition to mathematics, those academic
disciplines that are primarily mathematical in nature but may not be
universally considered subfields of mathematics proper." In other words,
数理系の研究者 use difficult mathematics to solve actual problems that matter in
human life, such as cryptography or machine learning.




数学 is (pure) mathematics.

数理 refers to [mathematical
sciences](https://en.wikipedia.org/wiki/Mathematical_sciences), "group of
areas of study that includes, in addition to mathematics, those academic
disciplines that are primarily mathematical in nature but may not be
universally considered subfields of mathematics proper." In other words,
数理系の研究者 use difficult mathematics to solve actual problems that matter in
human life, such as cryptography or machine learning.

