Isaac Newton proposed the concept of absolute space and time, believing they were independent entities that provided a framework for the universe.

General relativity posits that gravity is not a force but rather a curvature of spacetime caused by the presence of mass and energy.

Special relativity demonstrates that space and time are not absolute but are relative to the observer and interconnected through the concept of spacetime.

Spacetime continuum refers to the unified framework proposed by Albert Einstein, where space and time are treated as a single entity rather than separate dimensions.

Idealism, particularly subjective idealism, posits that space and time are mental constructs or ideas that exist only in the mind of the observer.

Time dilation is a phenomenon in special relativity where time passes slower for objects moving at high speeds relative to an observer.

String Theory is a theoretical framework that aims to unify general relativity and quantum mechanics by proposing that fundamental particles are not point-like but rather tiny, vibrating strings.

Length contraction is a phenomenon in special relativity where objects moving at high speeds relative to an observer appear shorter in the direction of their motion.

Gottfried Leibniz proposed the concept of relational space and time, asserting that they are not absolute entities but rather are defined by the relationships between objects.

Simultaneity is relative in special relativity, meaning that two events that occur simultaneously for one observer may not occur simultaneously for another observer moving at a different speed.

Loop Quantum Gravity is a theory that attempts to quantize space by proposing that it is composed of discrete units called Planck lengths, the smallest possible distance scale in the universe.

In general relativity, spacetime is not flat but is curved by the presence of mass and energy, leading to the phenomenon of gravitational fields.

Immanuel Kant proposed that space and time are subjective forms of intuition, meaning that they are inherent structures of human consciousness and not objective realities.

The cosmological constant is a constant energy density that permeates spacetime, contributing to the expansion of the universe and influencing its geometry.

The Block Universe Theory, also known as the Spacetime Block Theory, posits that time is an illusion and that all events exist simultaneously in a timeless, four-dimensional spacetime.