Physics Space

1 physics

1.1 classical mechanics
1.2 relativity
1.3 cosmology

physics

many of laws of physics, such various inverse square laws, depend on dimension three.

in physics, our three-dimensional space viewed embedded in four-dimensional spacetime, called minkowski space (see special relativity). idea behind space-time time hyperbolic-orthogonal each of 3 spatial dimensions.

classical mechanics

space 1 of few fundamental quantities in physics, meaning cannot defined via other quantities because nothing more fundamental known @ present. on other hand, can related other fundamental quantities. thus, similar other fundamental quantities (like time , mass), space can explored via measurement , experiment.

relativity

before einstein s work on relativistic physics, time , space viewed independent dimensions. einstein s discoveries showed due relativity of motion our space , time can mathematically combined 1 object–spacetime. turns out distances in space or in time separately not invariant respect lorentz coordinate transformations, distances in minkowski space-time along space-time intervals are—which justifies name.

in addition, time , space dimensions should not viewed equivalent in minkowski space-time. 1 can freely move in space not in time. thus, time , space coordinates treated differently both in special relativity (where time considered imaginary coordinate) , in general relativity (where different signs assigned time , space components of spacetime metric).

furthermore, in einstein s general theory of relativity, postulated space-time geometrically distorted- curved -near gravitationally significant masses.

one consequence of postulate, follows equations of general relativity, prediction of moving ripples of space-time, called gravitational waves. while indirect evidence these waves has been found (in motions of hulse–taylor binary system, example) experiments attempting directly measure these waves ongoing.

cosmology

relativity theory leads cosmological question of shape universe is, , space came from. appears space created in big bang, 13.8 billion years ago , has been expanding ever since. overall shape of space not known, space known expanding rapidly due cosmic inflation.