theory of relativity; relativistic physics. Developed by Albert Einstein in the early 20th century, it changed the understanding of space, time, and gravity, forming the basis of modern physics. It includes both 狭义相对论 xiá​yì​xiāng​duì​lùn and 广义相对论 guǎng​yì​xiāng​duì​lùn.

the philosophical doctrine that knowledge, truth, and morality exist in relation to culture, society, or historical context, and are not absolute