Universe

The Universe (Hebrew: היקום, HaYekom; Arabic: الكون, al-Kawn; Russian: Вселенная, Vsélennaya; Chinese: 宇宙, Yǔzhòu) is all of space and time and their contents, including planets, stars, galaxies, and all other forms of matter and energy. The Universe has been described as the totality of everything that exists, extends across all of space and time and encompasses all forms of substance, energy, and momentum. The study of the Universe, known as cosmology, is a branch of astronomy that seeks to understand the origin, evolution, and eventual fate of the Universe. According to the prevailing scientific model, the Universe began roughly 13.7 billion years ago with an inflationary event and has been expanding ever since. This expansion is governed by the laws of physics, which describe the fundamental interactions between all forms of matter and energy. The Universe is observed to be largely uniform on the largest scales, with small fluctuations giving rise to the large-scale structure of galaxies and galaxy clusters.