graviteits

Graviteits is the natural phenomenon by which masses attract each other. It operates across vast scales, from the fall of an apple to the motion of planets and the dynamics of galaxies. It is central to both everyday experience and modern physics.

Classical gravity is described by Newton's law of universal gravitation: F = G m1 m2 / r^2, where G is the gravitational constant. The law explains orbital motion, tides, and weight, and implies gravitational potential energy between masses. Experiments such as Henry Cavendish's measurements established the strength of this interaction, while observations of planetary motion and stellar dynamics confirmed its broad applicability.

General relativity provides a deeper description: mass-energy curves spacetime, and free-falling objects follow geodesics in that curved geometry. Predictions include the deflection of light by gravity, gravitational time dilation, and gravitational waves, all of which have been observed. Technologies such as the Global Positioning System rely on relativistic corrections to maintain accuracy.

In cosmology, gravity drives the growth of structure, from stars to galaxies to clusters. It interacts with the expansion of the universe and underpins phenomena such as dark matter halos and gravitational lensing, shaping the large-scale distribution of matter.

Open questions remain at the intersection of gravity and quantum physics. A quantum theory of gravity—appearing in approaches such as string theory or loop quantum gravity—seeks to describe gravity at the smallest scales, but no complete, experimentally confirmed theory currently exists.