Is it true that Japanese mathematicians, using an old Japanese model of mathematical problem solving that was replaced by Western models, could have solved the mysteries of black holes in space and invented a time travel machine? No, that's not true: Wasan, a Japanese school of mathematics used up to the 1800s based on ancient Chinese mathematics, did not involve calculus and mathematical models that would lead to the development of quantum physics, which is considered central to the understanding of black holes and theories of time travel.
The claim appeared on TikTok (archived here) by user @koaraaa0 on January 22, 2024. In the video, the narrator laments the loss of wasan, a type of mathematics developed in Japan, and claims if it had survived it would have led to the creation of time travel and solved the mystery of black holes. The narrator claims (translated from Japanese to English by Lead Stories staff):
Only Japanese people can make a time machine. In ancient Japan, a distinct type of mathematics called wasan developed independently ... Advanced mathematics such as hypercomplex equations and determinants were discovered a century before the West. Wasan ceased to exist after the Meiji Revolution and the introduction of Western mathematics into Japanese school curriculums. If wasan had continued to exist today, then we might've solved the mystery of the black hole.
This is what the post looked like on TikTok at the time of writing:
(Source: TikTok screenshot taken on Wed Feb 21 20:58:01 2024 UTC)
The theory of time travel and understanding of black holes relies on a deep understanding of quantum physics, which was discovered and honed through modern mathematics. The field of quantum physics was founded by Max Planck and his contemporaries in Germany (archived here), when the emergence of quantum ideas proliferated to explain various phenomena such as the black-body radiation problem (archived here).
Wasan was heavily based on ancient Chinese mathematics (archived here), which focused on calculation and algorithms rather than the philosophical foundations of Europe's mathematics in Greek thought (archived here), which made the foundation of quantum ideas possible.
This means that wasan shared the same mathematical priorities as ancient China, making it impossible for wasan alone to lead mathematicians and scientists to solve the theory of time travel or the mystery of black holes since the concept of quantum theory did not exist in Japan until its introduction in the early 1900s Meiji Period (archived here).