Introduction To Cosmology ✧ [RECOMMENDED]

An invisible form of matter that does not emit light but exerts gravitational pull, holding galaxies together.

The foundation of modern cosmology was laid in the early 20th century. Before this, most scientists—including Albert Einstein—assumed the universe was static and eternal. However, in 1929, Edwin Hubble observed that distant galaxies are moving away from us. More importantly, the further away a galaxy is, the faster it recedes. This discovery of proved that the universe is expanding, implying it must have had a beginning. 2. The Big Bang Theory Introduction to Cosmology

The study of cosmology is our attempt to understand the universe as a single, physical entity. While early humans looked at the stars and created myths to explain the heavens, modern cosmology uses the rigorous tools of physics and mathematics to answer the "big questions": Where did we come from, how is the universe structured, and how will it end? 1. The Expanding Universe An invisible form of matter that does not

If the universe is expanding today, it must have been smaller and denser in the past. The suggests that approximately 13.8 billion years ago, the entire observable universe was concentrated in a state of infinite density and heat called a singularity. However, in 1929, Edwin Hubble observed that distant