Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.
The Origin of the Universe Where and when did it all Begin...?
How do you think the Universe Began? • There are many scientific theories that suggest how the Universe began. • It is important to know the difference between theories and facts. • Theories: A conceptual framework that explains existing observations and predicts new ones. • Fact: A thing that is indisputably the case. Scientific facts are verified by repeatable experiments.
When discussing these types of topics in a classroom setting… • It is important to be sensitive and respectful… • Everyone has their own set of personal or religious beliefs…Which is a good thing! • When it comes to this topic, I will never tell you “what to think” or that “your belief is wrong”. • But I would also ask that you keep an open mind on the topic at hand…
Any Theories Floating Around? “What choice did God have in creating the Universe?” – Albert Einstein • Intelligent Design • Big Bang Theory • The Big Bounce • The Multiverse • Protouniverse • “Always has been” Just to name a few!
Cosmology • Cosmology is the study of the Universe. • Cosmologists study the structure and changes in the present Universe. • The Universe contains all of the star systems, galaxies, gas, and dust, plus all the matter and energy that exists now, that existed in the past, and that will exist in the future. • The Universe includes all of space and time!
Evolution of Human Understanding of the Universe • In the early 20th century, Hubble discovered that what scientists called the Andromeda Nebula was actually over 2 million Light years away – many times farther than the farthest distances that had ever been measured! • Hubble realized that many of the objects that astronomers called nebulas were not actually clouds of gas, but were collections of millions or billions of stars – what we now call galaxies!
Hubble showed that the Universe was much larger than our own galaxy. • Today we know that the Universe contains about a hundred billion galaxies – about the same number of galaxies as there are stars in our Milky Way Galaxy! • Hubble’s discoveries are an excellent example of how the idea of a “Universe” has changed through Human history! The Universe is pretty darn big! But how big…? http://www.youtube.com/watch?v=17jymDn0W6U
“Yo teach! You mentioned something called a ‘Light Year’ earlier. What is that??? • A light year is the distance that light travels in one year. • Light travels at a speed of 186,287.5 miles per second! • A light year is 9.4607 x km or just nearly 6 trillion miles! • The distance from the Earth to the Sun is 93 million miles. The distance to the nearest star is 4.3 light years. http://www.youtube.com/watch?v=j2uWp8WpGwY
So what is the leading Scientific theory when it comes to the origin of the Universe? • The Big Bang Theory! • No not that one! • How did everything begin in the Big Bang?
The Big Bang Theory • Recall that Georges Lemaitre suggested that the Universe must be expanding because distant galaxies are moving away from us. • If the Universe is expanding, the next logical thought is that in the past it had to have been smaller. A single infinitesimally small point even! • The time when the Universe began is the explosion known as the Big Bang. http://www.youtube.com/watch?v=xhLQ_b3bKdI
The Big Bang Theory is the most widely accepted cosmological explanation of how the Universe formed. • According to the theory, the Universe began about 13.7 billion years ago! • Everything that is now in the Universe was squeezed into a very small volume. Imagine all of the known universe in a single, hot, chaotic mass!
An enormous explosion – a big bang – caused the Universe to start expanding rapidly. All the matter and energy in the Universe, and even space itself, came out of this explosion. http://www.youtube.com/watch?v=nVsHjnY-o9s
So what about after the Big Bang? • In the first few moments after the Big Bang, the Universe was unimaginably hot and dense. • As the Universe expanded, it became less dense and began to cool. • After a few seconds, protons, neutrons, and electrons could form! • After a few minutes, those subatomic particles came together to create hydrogen.
Energy in the Universe was great enough to initiate nuclear fusion, and hydrogen nuclei were fused with helium nuclei. • The first neutral atoms that included electrons did not form until about 380,000 years later! • The matter in the early universe was not smoothly distributed across space. Dense clumps of matter held close together by gravity were spread around. • Eventually, these clumps formed countless trillions of stars, billions of galaxies, and other structures that now form most of the visible mass of the Universe!
Background Radiation • After the origin of the Big Bang hypothesis, many astronomers still thought the Universe was static. • Nearly all came around when an important line of evidence for the Big Bang was discovered in 1964. • In a static Universe, the space between objects should have no heat at all; the temperature should measure 0 K (Kelvin is an absolute temperature scale).
However, two researchers at Bell Laboratories used a microwave reciever to learn that the background radiation in the Universe is not 0 K but 3 K. • This tiny amount of heat is left over form the Big Bang!
George Smoot, a scientist at Lawrence Berkeley Nation Lab, used background radiation detected by the Cosmic Background Explorer Satellite (COBE) to make a picture of the Universe when it was 12 hours old! • No big deal right? http://science.kqed.org/quest/video/nobel-laureate-george-smoot-and-the-origin-of-the-universe/
In Summary… • There have been many theories proposed about the true origin of the Universe. • The idea of a ‘Universe’ has changed through human history. • Edwin Hubble saw the enormity of space and determined that there was much more than our own galaxy. • Georges Lemaitre’s Big Bang theory states that the Universe began as a point and expanded outward. • No one can know what came before the Big Bang because there is no remaining evidence. • The Tiny bit of background radiation in the Universe is energy remaining from the Big Bang.
Have you ever asked yourself the big question though: Does the Universe even have a purpose? http://www.youtube.com/watch?v=7pL5vzIMAhs