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Rated 4 out of 5 by Thomas G from A great way to expand your perspective This course really gives cause to wonder about our place in the world and what may be out there. It made my brain hurt in the best way possible. ... I did get a little confused, though, concerning the numbers. It seems they are way off what others sources cite; small numbers are very very very much smaller, and large numbers are very very very much larger. For example, other TGC courses that touch on inflation say that inflation involved expansion by a factor 10^50 from 10^(-34) to 10^(-32) seconds (by way of 100 doublings). This course says that inflation involves expansion by a factor 10^1,000,000 in 10^(-48) seconds, and talks about distances of 10^1,000,000 meters. (1 light year is approx. 10^16 m, and so 10^1,000,000 m is around 10^999,984 light years, which is 10^999,973 times the size of the current observable universe. In 10^(-48) seconds.) This sounds ludicrous. Are we talking about different kinds of inflation, or, if not, which one is correct?

Date published: 2023-08-25

Rated 5 out of 5 by telax from One of the most informative courses on subject One of the most informative courses on subject I have seen and so well presented ........ excellent. For me it went into the depth I wanted with a lot of common alternative approaches to the different topics discussed mentioned. He also broke down difficult topics to make them clearer and discussed when his analogies fell short of explaining the topic. A very skilled lecturer and very insightful about his audience ............

Date published: 2023-07-09

Rated 5 out of 5 by New Geezer from Very Understandable For All Experience Levels I took this course because I have some physics background and I rely on Great Courses physics courses to update my physics knowledge and interest. I took honors physics as an undergrad engineering student in the 1960s. So much has happened in the field of physics since then. The Big Bang was too new then to be covered when quantum mechanics and special relativity were covered. I had not reviewed much about the Big Bang since then and wanted to know more. Professor Felder speaks slowly and precisely which is ideal for this subject matter. The course material and presenter are remarkable in that I don't feel it matters much what your physics background is or if you have none. I believe you can still gain a good understanding of the Big Bang from this course. The course is remarkably easy to follow as long as you pay close attention. If you should nod off occasionally like us senior citizens, the printed guide follows the lectures very closely, so all you have to do is read the guide for a few minutes to catch up what you missed. The course is remarkable in covering so much material so broadly in only 12 lectures. I have viewed over 50 Great Courses, and I have liked none better than this one. Professor Felder does a great job of telling you if a theory has been verified experimentally or if it is speculative at this time. The speculative theories are interesting, but exceed our technical limits to make verifying measurements at this time. They do tend to have some basis in mathematics however. For example, physicists know what the Planck density is which is thought to have existed at the beginning of the Big Bang, but do not have the technical means to create matter at such a high density in an experiment. In lecture 10, on the Origin of the Constants of Nature, he addresses different possible philosophical viewpoints respectfully before explaining the Anthropic Principle which is a controversial and speculative idea from a physics point of view. I was sort of initially disappointed when he referred to the possible role of a scalar energy field in kicking off the Big Bang with expansion. However, as I looked up the definition of a scalar field and thought about it, he was right on track as physicists don't know much more about that particular scalar field at this time.

Date published: 2023-03-04

Rated 5 out of 5 by MikeInEngland from A complex subject explained with great clarity Although most of this course consists of simple "piece to camera", I nevertheless found it interesting, informative and clearly explained. For me, I know the content has been carefully thought out when a question springs into my mind to which, soon after, the lecturer provides the answer. Congratulations to the Professor on a job well done!

Date published: 2023-01-24

Rated 5 out of 5 by T Steve from The Big Bang and Beyond An excellent introduction to the start of the present universe. The pressures and temperatures at the start of the "Big Bang" are unimaginable. Clearly presented. Thanks

Date published: 2022-11-27

Rated 5 out of 5 by alexander1 from extraordinary, masterful I have been fortunate to watch 100's of lectures in the original Great Courses and this course is among the VERY best. The lecturer is engaging and articulate and the subject matter ( anti-matter..heh,heh) is made extremely interesting. The course does not require a background in math ,cosmology, or particle physics. A true delight! Thank you Dr. Felder

Date published: 2022-10-03

Rated 5 out of 5 by icalv5 from Big Bang without the bang Love this lecture series! The Big Bang Theory - the long story (made short) after the Bang. Interesting! Easy to follow and remember! Thank you!

Date published: 2022-09-27

Rated 5 out of 5 by Charles M from Easy to Understand Very forthright about what we are pretty sure we know, and why we think we know it, and what what is still unknown or just speculation. For example, the Big Bang theory doesn't work without "Inflation", but no one knows what caused the inflation to happen. We speculate it could be a "scalar field", but don't really know.

Date published: 2022-09-17

Overview

Taught by Professor Gary Felder of Smith College, this course covers the history of the early universe starting with the Big Bang and continuing to the formation of the first stars and galaxies hundreds of millions of years later. Professor Felder also looks ahead to the ultimate fate of the universe and to speculation on what may have happened before the Big Bang.

About

Gary Felder

The early universe is one of the most intellectually exciting fields that humans can explore.

ALMA MATER

Stanford University

INSTITUTION

Smith College

Gary Felder is a Professor of Physics at Smith College. He earned his BA in Physics with high honors at Oberlin College and Conservatory and his PhD in Physics at Stanford University. He completed postdoctoral work at the Canadian Institute for Theoretical Astrophysics in Toronto.

Gary has published papers in cosmology, nuclear physics, and education. One of his papers was selected as a highlight of the year by the journal Classical and Quantum Gravity, and another won the William Elgin Wickenden Award for the best paper of the year in the Journal of Engineering Education. He is the coauthor of two physics textbooks: Mathematical Methods in Engineering and Physics and Modern Physics.

Gary has given hundreds of public lectures, school demonstrations, and traveling science shows to audiences ranging from elementary schools to retirement communities. He has won grants from the National Science Foundation, the Mellon Foundation, the North Atlantic Treaty Organization, and bp. He received the Smith College Faculty Teaching Award, the only teaching award at Smith administered by students.

By This Professor

The Big Bang and Beyond: Exploring the Early Universe

Trailer

01: The Big Bang Changes Everything

Explore the highlights of the Big Bang model, which says that the universe evolved from an initial hot, dense state billions of years ago. Find that the Big Bang wasn’t a moment when the cosmos had zero size, it didn’t take place at a special point in space, and it wasn’t necessarily the beginning of the universe. Rather, it was the energetic start of the expansion phase that is still underway.

33 min

02: The First Few Minutes of the Universe

Beginning a hundred-billionth of a second after the Big Bang, trace events as the universe quickly cooled from a quadrillion degrees. Learn about the strong, weak, and electromagnetic forces, and the fundamental particles—all of which precipitated from the seething cauldron of energy, even as matter and antimatter were mutually annihilating. Within 3 minutes, hydrogen and helium nuclei had begun to form.

28 min

03: First Galaxies, First Stars, and Dark Matter

Continue the story of the early universe by exploring such highlights as the formation of the first atoms at 370,000 years, when space transitioned from opaque to transparent; the accretion of hydrogen and helium gas into protogalaxies after millions of years due to the gravitational influence of dark matter; and the collapse of the gas into ever denser balls eventually leading to the first stars.

31 min

04: How Big Was the Big Bang?

Is it possible to calculate the size of the universe at the instant of the Big Bang? Assemble the clues that scientists use to address this question. In the process, discover a number of remarkable properties of the universe, including that it must be bigger that what we can see, extending beyond the boundary that limits our knowledge due to the finite speed of light and the age of the universe.

31 min

05: Mysteries That Reshaped the Big Bang Model

Evaluate three mysteries connected to the Big Bang model that baffled theorists beginning in the late 1960s. Why was the early universe so uniform? Why does the universe obey the laws of geometry we teach in high school? And how did the universe come to be made of the kinds of particles we see and not others? A single solution to all three questions seemed too much to hope for, yet one turned up.

31 min

06: Inflation! The First Fraction of a Second

Dig into the bizarre theory of inflation developed by physicist Alan Guth, which holds that for a fraction of a second just after the Big Bang the universe expanded at a mind-boggling rate, making the cosmos effectively infinite. Analyze how this idea solves the three puzzles introduced in Lecture 5. Learn about associated concepts, such as the scalar field and its decay, known as “reheating.”

32 min

07: What Caused Inflation: The Scalar Field

Can inflation possibly be true? See how a concept called a scalar field may be the inconceivably high-energy medium that spontaneously triggered inflation, leading to the observable universe—and more—in a billionth of a billionth of a billionth of a billionth of a second. Probe a rival theory that the Big Bang was caused by the collision of two universes in four-dimensional space.

31 min

08: More than One Big Bang in a Multiverse?

At one time, Earth was considered the center of the cosmos. Might the idea that the Big Bang was the beginning of everything be just as parochial? Take a mindboggling trip through the theory of eternal inflation—that our observable universe is a nearly infinitesimal speck inside a much larger, older, and eternally growing multiverse, in which inflation continually sprouts new universes like ours.

30 min

09: Other Universes across Other Dimensions?

Many physicists believe that our universe really isn’t three dimensional, but only appears so to us. Explore what it would mean if there are extra dimensions that we can’t see. Learn how to visualize this counterintuitive state, and examine what it implies for Big Bang theory and the concept of a multiverse. One set of ideas that calls for at least nine dimensions is string theory.

31 min

10: The Origins of the Constants of Nature

Constants of nature, such as the gravitational constant, appear to be fine-tuned to make life possible. Is this a coincidence of astronomical unlikelihood, an expected outcome of the nature of the universe, or does it imply that ours is one of many universes with different properties? Consider this question in light of the anthropic principle which takes the existence of observers into account.

30 min

11: From the Big Bang to the Universe’s Fate

Learn that the ultimate fate of the universe is tied to its beginning—to the as-yet-unknown conditions that preceded the Big Bang. Focus on the importance of dark energy, an enigmatic force discovered in the 1990s that is causing the universe to expand at an accelerating rate. Compare three scenarios that lead to either infinite expansion or eventual collapse in a Big Crunch.

31 min

12: The Future of Early Universe Cosmology

Conclude the course by reviewing the history of the universe, highlighting the major gaps in our knowledge. Then turn to four promising areas of experimental research that may provide answers. Let your imagination soar by contemplating theoretical possibilities such as this one: Could we exploit inflation to create a baby universe in the lab? Do we, in fact, live in someone else’s baby universe?

34 min