The Origin Of The Universe Lesson 1 PDF

The Origin of the universe  Quick Recap: What is the closest spiral galaxy to the Milky way?  Quick Recap: What do you think is the estimated age of the universe? Hypothesis It is an assumption, an idea that is proposed for the sake of argument so that it c...

The Origin of the universe  Quick Recap: What is the closest spiral galaxy to the Milky way?  Quick Recap: What do you think is the estimated age of the universe? Hypothesis It is an assumption, an idea that is proposed for the sake of argument so that it can be tested to see if it might be true.  Theory A system of statements targeted at describing, explaining, and predicting real-world phenomena. It is a principle that has been formed as an attempt to explain things that have already been substantiated by data. Structure, Composition and Age The universe is made of 4.6% baryonic matter, 24% cold dark matter and 71.4% dark energy Hydrogen, helium and lithium are the three most abundant elements Stars - the building blocks of galaxies, are born out of clouds of gas and dust galaxies Protostar - a hot core future star as thermonuclear reactions sets in. Structure, Composition and Age Based on a recent data, the universe is 13.8 billion years old. The diameter of the universe is possibly infinite but should be at least 91 billion light years. Big Bang Theory The big bang theory is cosmological model that explains how the universe began. It suggests that the universe started its expansion about 13.8 billion years ago. The concept of big bang as not a literal explosion of something leading to the creation of the universe.  Big Bang Theory and the Bread-Raisin Model The bread represents the universe; while raisins are galaxies. The galaxies, represented by dots, are not expanding.  Distances in relation to other galaxies just increases because of the expanding universe. Singularity The universe started as a “singularity”- an area predicted to be in the core of a black hole with very high temperature and density The intense heat resulted to formation of matter and antimatter particles that were destroyed every time they collided with each other. Nucleosynthesis is the formation of elements, such as H and He. Presence of these elements led to the formation of stars and galaxies. Elements = Stars and Galaxies Evidences that Support the Big Bang Theory The expansion of the universe is supported by the observation that galaxies are receding from us. The high amount of light elements like H, He and Li. These elements were formed through the fusion of protons and neutrons immediately after the Big Bang. The detection of the cosmic microwave background (CMB) radiation which is the residue or heat leftover from the Big Bang. Proponents of the Big Bang Theory Georges Henri Joseph Edouard Lemaître was the first proponent of the theory. He suggested the idea of the expanding universe Edwin Powell Hubble who established the Hubble’s law which provided an evidence that the universe was not static but expanding. Proponents of the Big Bang Theory Georges H.J. Lemaitre Edwin Powell Hubble Drawbacks of the Big Bang theory It failed to explain how the universe was created. It just explains how it evolve and not where it originated. It also failed to explain how the galaxies formed.  Keypoints Big bang theory suggests that the universe started as a “singularity” - an area predicted to be in the core of a black hole with very high temperature and density. Proponents of the idea of an expanding universe are Georges Henri Joseph Edouard Lemaître, Edwin Powell Hubble  Keypoints Hubble’s law states that the relationship of the velocities of distant objects in the universe is directly proportional to their distance from Earth. The big bang theory failed to explain how the universe was created. Steady State Theory The steady state theory is another view that proposes that the universe has always been expanding. As the universe expands, new stars and galaxies are formed at the same rate that old ones become unobservable due to distance and recession velocity.  Despite the continuous expansion, the average density of the universe remains the same; hence, the name steady. state. In the steady state theory, matter is constantly created as the universe expands. The universe according to the Steady State Theory: Has no beginning and has no end. Has always been here and will always be present. Always looks the same in any time and space. Creates new matter as it continuously expands. Proponents of the Steady State Theory Hermann Bondi, Thomas Gold, and Fred Hoyle proposed the steady state theory in 1948. Oscillating Theory Oscillating Universe theory, alsoknown as pulsating theory,proposes that the universe is expanding and will contract once all the energy after the big bang has been used up. The oscillating universe theory suggests that once the universe reverses and attains the point of singularity, another universe will be born. Proponents of the Oscillating Theory Richard Tolman, a Caltech professor, proposed it. Tolman called the birth of another universe as the big bounce. Drawbacks of the Oscillating theory The suggestion that the universe would collapse on its own after it reached its full expansion violates some current laws of physics, such as the postulated existence of dark energy. The currently postulated end of the universe is by big freeze or heat death.  Keypoints Steady state theory violates the law of conseration of mass and energy. Both the steady state theory and big bang theory suggest that the universe is expanding. Oscillating universe theory violates current laws of physics laws such as the postulated existence of dark matter. The Origin of the Solar System Nebular Theory According to the Nebular Theory, the solar system originated from a nebula. It is the widely accepted view about the formation of the solar system some 4.5 billion years ago. A nebula is defined by NASA as giant cloud of gas and dust in space. This interstellar cloud of dust contains hydrogen, helium and other ionized gases. Major Steps in the Formation of the Solar System The formation of the solar system from a nebula occurs in three major steps: (1) cloud collapse, (2) formation of protoplanetary disk, and (3) growth of planets. Proponents of the Nebular theory Emanuel Swedenborg Immanuel Kant Pierre-Simon Laplace Terrestrial Planets Includes Mercury, Venus, Earth, and Mars, were formed because only the materials with higher densities and melting points were able to form near the very high temperature of the Sun. Jovian Planets Composed of Jupiter, Saturn, Uranus, and Neptune, are huge planets made up of gases without land surfaces. These planets were formed farther from the Sun because the temperature away from the Sun was cool enough for gases to condense, forming these less dense planets. Encounter Theory The Encounter Theory proposes that the planets were formed from the material ejected from the sun during an encounter with another celestial object, such as another star. Protoplanet Hypothesis Protoplanet hypothesis is a modified version of the nebular hypothesis. Just like the nebular theory, protoplanetary theorists Carl von Weizsäcker and Gerard Kuiper believed that the solar system started from a nebula. Current hypothesis Try to answer this! _________ 1. This theory suggests that the solar system formed after a star passed near the Sun. _________ 2. According to the Nebular Theory, what comprises a nebula? _________ 3. Which of the following is not a member of our solar system? A. asteroids B. Polaris. C. Sun. D. Pluto _________ 4. Who among the following theorists suggested the Protoplanet Theory? _________ 5. What are the three most abundant elements in the universe? Assignment: What is the fate of the universe? Will the universe continue to expand or will it eventually contract because of gravity? References: Rodney Holder and Simon Mitton. 2013. Georges Lemaître: Life, Science and Legacy, Germany: Springer Science & Business Media. John Chambers and Jacqueline Mitton. 2013. From Dust to Life: The Origin and Evolution of Our Solar System, New Jersey: Princeton University Press. Michael Mark Woolfson. 2012. Time, Space, Stars and Man: The Story of the Big Bang, Singapore: World Scientific.