The first light of the universe – piercing through the gas in between galaxies скачать в хорошем качестве

The first light of the universe – piercing through the gas in between galaxies

The universe at present is filled with gas that is hot and transparent to ultraviolet light. But shortly after the Big Bang, the gas was cold and opaque. How did the gas go through such a big transition in its physical state, and how did this transition affect the evolution of the universe afterwards? The answer to these questions lies in the power of the light emitted from the first stars and galaxies, which pierced through the gas in the early universe and transitioned the entire universe. Why don’t we follow the first light of the universe from the “dark ages” of the cosmos when no star existed, to the cosmic dawn when the first stars and galaxies formed. We will see how the first light fought its journey through the opaque gas in the early universe and lit everything up. Speaker Xiaohan Wu completed her Bachelor of Science in Astronomy from Peking University. She is currently pursuing her Ph.D. in Astronomy and Astrophysics at Harvard University. Her research focuses on the evolution of the universe when the universe was only hundreds of millions of years old. Besides science, she is also an amateur ballet dancer and is the physics category winner of the Dance Your PhD competition in 2022. Glossary of Important Terms Proton: component of a hydrogen atom, having positive charge Electron: component of a hydrogen atom, having negative charge Ionize: the process of breaking apart the proton and electron in a hydrogen atom using ultraviolet radiation Neutral and cold: state of a hydrogen atom where the proton and electron are bound together; in a gas full of neutral hydrogen atoms, it has a temperature of about -100 degrees celsius Ionized and hot: state of a hydrogen atom where the proton-electron bond is broken; when hydrogen atoms are ionized, protons and electrons can float around and the gas has a temperature of about 10,000 degrees celsius Diffuse: used to describe the very low density of the gas in between galaxies, about 1 atom per cubic meter Reionization: a period of time when the universe was hundreds of millions of years old, during which the cold and neutral hydrogen atoms in the universe were turned into a hot and ionized state. Density field: map of the distribution of matter in the universe Gravity: the force that pulls things together, just like earth pulls an apple to its center so that the apple falls off of a tree Resources to learn more Xiaohan Wu Dance Your PhD 2022 video    • Dance Your PhD 2022 - The journey of a pho...   Spandex gravity    • Spandex Gravity Well (+instructions to mak...   KIPAC movies on galaxy formation, reionization, first stars https://kipac.stanford.edu/education/...