PPT-Implications of the Uniform Expanding Universe

Run time backwards all the matter has to be together at the same place and at the same time Universal Expansion V r H o D Time DV The Ant Universe Ants on surface of a balloon are a good model the ants can traverse the surface of the balloon and never run into a boundary. Lecture . 10; . May . 14 2013. Previously… on astro-2. If the universe is homogenous and isotropic and correctly described by General Relativity:. At any given time the universe is a 3D space. It could be open/close/flat. Significance . of a dark night . sky. The Universe . is expanding. The . Big Bang. initiated the expanding Universe. Microwave radiation . evidence . of the . Big Bang. The Universe was initially hot & opaque. Cosmology. The Study of the Creation and Evolution of the Universe as an entity. Did the Universe have a beginning?. If so, how did it begin?. When did it begin?. Has the Universe changed over time?. w. here does it end?. Chris North. Cardiff University. The speed of light. c = 299,792,458 m/s. . or 670,616,629 miles per hour. . or 2 million . million. furlongs per fortnight. or ~300,000 km/s. The Milky Way Galaxy. When you look into the hazy band of light across the sky, you are actually looking at our galaxy from the inside. While an awesome sight, you can only truly begin to see it if you get away from city lights on a moonless night. . Lecture 3; April . 11 2013. Previously.. On Astro-2. The universe is much larger than the Milky Way (Gpc vs kpc). There are billion of galaxies, the Milky Way is average Joe galaxy. Most galaxies can be classified based on their appearance as . 11. . What do you observe about the direction of the light shift for these galaxies?. Observation #1: . ALL GALAXIES ARE REDSHIFTED. What does this observation imply about the motion of galaxies relative to us?. Universe. Imagine that you find a star with an unknown distance, but you notice that it has a distinctive characteristic that tells you that it is a specific type of star. And let’s imagine that all stars of that type have the same luminosity, and you happen to know the value of that luminosity. You can then estimate the distance for the star you found from the inverse square law of light:. Darci. Collins. Beginning of the Universe. In Medieval philosophy there was much debate over whether the universe had a finite or infinite past . Johannes . Kepler. used the dark night sky to argue for a finite universe.. 2014. Professor Patrick Hall . [phall@yorku.ca]. Assoc. Professor & Undergraduate Program Director. Department of Physics and Astronomy. Faculty of Science. York University. Science Resources at York. The universe is a big place, perhaps the biggest. . –Kurt Vonnegut. Cosmology. Cosmology is the study of the nature of the universe, how the universe began and how it will end, if it does. There is religious cosmology, and scientific cosmology. Older ….. larger … colder ….less energetic. now. Big Bang. Prediction of Cosmic Microwave Background radiation. λ. emitted. = 1 . μ. m. T. emitted. = 3000 K. R. observed . = 1000. R. emitted. Astro. Ch. 11-1. Cosmology. The . study of the nature, origin, and evolution (how it changes) of the universe. Basically . the study of the universe as a whole. Cosmology . is an attempt to understand how the universe works. The expanding Universe. Recap. Milky . Way. Distances in the Milky Way: our Galaxy is very large. Other galaxies. Galaxy . properties. Morphology: spiral and elliptical galaxies, spirals can appear different depending on viewing .