gravitational

Gravitational refers to the natural phenomenon by which all objects with mass or energy attract one another. The study of gravitational phenomena encompasses the gravitational field, gravitational force, and gravitational potential, and it governs the motion of planets, stars, galaxies, and the bending of light in curved spacetime.

In classical theory, Newtonian gravity describes the force of attraction between two masses as F = G m1 m2 / r^2, where G is the gravitational constant and r is the separation. This inverse-square law explains orbital dynamics, tides, and the binding energy of systems. Gravitational potential energy in this framework is -G m1 m2 / r. The Newtonian description is highly successful for weak fields and low speeds.

General relativity provides a more comprehensive description, portraying gravity as the curvature of spacetime produced by mass-energy. Objects move along geodesics in curved spacetime, leading to phenomena such as gravitational time dilation, light deflection, and gravitational redshift. This theory accounts for effects like the precession of Mercury’s orbit and is essential for the accuracy of technologies such as GPS, which require relativistic corrections.

Gravitational waves are ripples in spacetime generated by accelerating masses, notably merging black holes and neutron stars. Predicted by general relativity, they were directly detected for the first time in 2015, opening a new observational channel for astronomy and cosmology.

Gravity dominates the structure and dynamics of the universe on large scales, governing orbital motion, galaxy formation, and cosmic evolution. It remains an active area of research, including efforts to unify it with quantum mechanics into a theory of quantum gravity.