Universe

The universe refers to all of space-time, including all matter, energy, planets, stars, galaxies, and the physical laws that govern them. It encompasses the vastness of everything that exists, from the smallest subatomic particles to the largest cosmic structures. The universe is often described as containing everything from the moment of the Big Bang, approximately 13.8 billion years ago, to the present day. It is characterized by its expansion, which has been observed through the redshift of distant galaxies. The universe includes not only observable elements but also aspects that remain elusive, such as dark matter and dark energy. Overall, the universe is a central concept in cosmology, physics, and philosophy, representing the entirety of existence and the framework in which all cosmic phenomena occur.