Never stop learning with Curiosity Learning Paths!

  • Get inspired with the web’s best bite-sized learning content, curated for learners like you.
  • Learn more—quickly and easily—by exploring our dynamic Learning Paths.
  • Spread quick knowledge to friends with our original Smart Memes!

What Is The Big Bang Theory?

This learning path has been created for you.
Playlist Description

KABOOM! That sound could have been the universe as we know it coming to life in an instant, according to one predominant scientific theory, The Big Bang. The Big Bang theory says that the universe began as a tiny, extremely compacted ball of mass that contained everything in the universe. More than 13.7 billion years ago, that ball of mass exploded and unleashed the incredible and infinite powers of our universe: galaxies, dark matter, invisible mass, planets, stars and much more. The theory, championed by scientists Robert Wilson and Arno Penzias more than 50 years ago, noted the presence of cosmic microwave background—a type of cosmic fog—that allowed them to explore a region of the universe they'd not yet encountered—and it went pretty far back. From what we know today, our universe continues to expand at an increasingly fast rate. One theory called eternal inflation suggests that we are in fact part of a multiverse—the mind-blowing idea that there is more than one universe.

From what we now know, our time to gather evidence on the origins, function and nature of the universe is both crucial and fleeting. Because of the universe's rapid expansion, it will eventually become impossible to peer over into other galaxies beyond our own Milky Way—that means the time to study infinity and beyond is now. Put on your lab jacket and take notes as experts and researchers delve into their theories on the origins of the universe, and where we're headed next.

06:28
Add to Playlist
Watch Later Added
  • Actions
  • About This Video
"The question of what caused the Big Bang is one of the most difficult facing humanity. We may never find an answer, and even if we do, we probably won't understand it. It's difficult to imagine an event occurring without a cause, and yet, that is precisely the prospect we are faced with when it comes to this question." © Tony Darnell Website: http://www.deepastronomy.com/
02:21
Add to Playlist
Watch Later Added
  • Actions
  • About This Video
"It is really a high density situation that we call the big bang, but there is really no explosion," says Freese. "There is no 'bang.' There is no singular point." Question: Does it make sense to ask what preceded the Big Bang?Katie Freese: I think people have the misconception that the big bang is the universe starting from a point.  In fact, it is very different from that.  Probably you know that the Universe is expanding, so if we go backwards in time then you can watch the Universe contract as you go backwards in time.  So for example, if you took a tabletop then any two points would get closer together, but the points that are way far apart if you had...  Let's say it's an infinite tabletop, so as these points get closer and closer together you still have a tabletop that is infinite in extent.  It's not like everything comes into one point, but eventually you reach such a high density.  Things are so compact and right on top of each other that we lose our description.  Physics fails.  That is what the big bang is, so it's actually we would need to have a theory of quantum mechanics and gravity simultaneously to be able to discuss physics going backwards in time any further, so it is really a high density situation that we call the big bang, but there is really no explosion.  There is no bang.  There is no singular point.  But so yes, it does make sense to ask well what happens when you reach that density and that is what people are trying to do in theories of quantum gravity such as string theory or well some of the cosmology that I've done also is in the context of brains where our observable universe is living on a three dimensional surface in a higher dimensional universe and there could be other brains out there and how these brains intersect one another and their motions and so on has been...  So there are different avenues to try to push back our level of knowledge and they are very active, but very difficult.Everything was more dense and then there is a certain point where... which we call the big bang and it's from that point forward that we start our clocks, so that's...  And then so and we say the universe is 13.7 billion years old is relative to that very high density situation. Recorded May 7, 2010Interviewed by David Hirschman Question: Does it make sense to ask what preceded the Big Bang?Katie Freese: I think people have the misconception that the big bang is the universe starting from a point.  In fact, it is very different from that.  Probably you know that the Universe is expanding, so if we go backwards in time then you can watch the Universe contract as you go backwards in time.  So for example, if you took a tabletop then any two points would get closer together, but the points that are way far apart if you had...  Let's say it's an infinite tabletop, so as these points get closer and closer together you still have a tabletop that is infinite in extent.  It's not like everything comes into one point, but eventually you reach such a high density.  Things are so compact and right on top of each other that we lose our description.  Physics fails.  That is what the big bang is, so it's actually we would need to have a theory of quantum mechanics and gravity simultaneously to be able to discuss physics going backwards in time any further, so it is really a high density situation that we call the big bang, but there is really no explosion.  There is no bang.  There is no singular point.  But so yes, it does make sense to ask well what happens when you reach that density and that is what people are trying to do in theories of quantum gravity such as string theory or well some of the cosmology that I've done also is in the context of brains where our observable universe is living on a three dimensional surface in a higher dimensional universe and there could be other brains out there and how these brains intersect one another and their motions and so on has been...  So there are different avenues to try to push back our level of knowledge and they are very active, but very difficult.Everything was more dense and then there is a certain point where... which we call the big bang and it's from that point forward that we start our clocks, so that's...  And then so and we say the universe is 13.7 billion years old is relative to that very high density situation. Recorded May 7, 2010Interviewed by David Hirschman
05:39
Add to Playlist
Watch Later Added
  • Actions
  • About This Video
Subscribe Now: http://www.youtube.com/subscription_center?add_user=ehoweducation Watch More: http://www.youtube.com/ehoweducation The Big Bang Theory is a complicated process with a lot of mathematical knowledge. Get a simple explanation of the Big Bang Theory in astronomy with help from an astrophysicist in this free video clip. Expert: Eylene Pirez Filmmaker: bjorn wilde Series Description: Astronomy and the study of outer space raise seemingly infinite questions. Travel into space and get some answers with help from an astrophysicist in this free video series.
13:19
Add to Playlist
Watch Later Added
  • Actions
  • About This Video
David Christian explains how the Big Bang theory developed by looking at the evidence that supports it. Website: https://www.bighistoryproject.com/portal Facebook: https://www.facebook.com/bighistoryproject Twitter: https://twitter.com/BigHistoryPro
05:20
Add to Playlist
Watch Later Added
  • Actions
  • About This Video
Support MinutePhysics and MinuteEarth on Subbable - http://www.subbable.com/minuteearth AND http://www.subbable.com/minutephysics MinutePhysics is on Google+ - http://bit.ly/qzEwc6 And facebook - http://facebook.com/minutephysics And twitter - @minutephysics Minute Physics provides an energetic and entertaining view of old and new problems in physics -- all in a minute! Music by Nathaniel Schroeder http://www.soundcloud.com/drschroeder Thanks to Nima Doroud for contributions.
01:27
Add to Playlist
Watch Later Added
  • Actions
  • About This Video
FREE Audiobook on Audible: http://bit.ly/ZEAtPh MinutePhysics is on Google+ - http://bit.ly/qzEwc6 And facebook - http://facebook.com/minutephysics And twitter - @minutephysics Minute Physics provides an energetic and entertaining view of old and new problems in physics -- all in a minute! Music by Nathaniel Schroeder http://www.soundcloud.com/drschroeder Thanks to Nima Doroud for contributions.
04:03
Add to Playlist
Watch Later Added
  • Actions
  • About This Video
Full lecture: http://www.youtube.com/watch?v=0NbBjNiw4tk Theoretical physicist Michio Kaku explains the basics of String Theory in this clip from his Floating University lecture.
02:07
Add to Playlist
Watch Later Added
  • Actions
  • About This Video
CURIOSITY premieres Sunday, August 7, 2011 @ 8PM e/p with DID GOD CREATE THE UNIVERSE? on Discovery. | http://curiosity.discovery.com/#mkcpgn=ytdsc1 | How could something appear out of nothing? Explore the possibilities of how our universe came into existence with Stephen Hawking.
03:07
Add to Playlist
Watch Later Added
  • Actions
  • About This Video
Complete video at: http://fora.tv/2009/05/23/Marcus_Chown_in_Conversation_with_Fred_Watson Marcus Chown argues that as more and more ideas are "tacked on" to the original big bang theory, it's becoming apparent that there is "a really, really big idea missing." He predicts "someone in the next...10-15 years is going to come up with the missing idea." ----- The two towering achievements of modern physics are quantum theory and Einsteins general theory of relativity. Together, they explain virtually everything about the world in which we live. But almost a century after their advent, most people havent the slightest clue what either is about. Radio astronomer, award-winning writer and broadcaster Marcus Chown talks to fellow stargazer Fred Watson about his book Quantum Theory Cannot Hurt You. - Australian Broadcasting Corporation Marcus Chown is an award-winning writer and broadcaster. Formerly a radio astronomer at the California Institute of Technology, he is now cosmology consultant of the weekly science magazine New Scientist. The Magic Furnace, Marcus' second book, was chosen in Japan as one of the Books of the Year by Asahi Shimbun. In the UK, the Daily Mail called it "a dizzy page-turner with all the narrative devices you'd expect to find in Harry Potter". His latest book is called Quantum Theory Cannot Hurt You.
05:27
Add to Playlist
Watch Later Added
  • Actions
  • About This Video
Almost all astronomers agree on the theory of the Big Bang, that the entire Universe is spreading apart, with distant galaxies speeding away from us in all directions. Run the clock backwards to 13.8 billion years ago, and everything in the Cosmos started out as a single point in space. In an instant, everything expanded outward from that location, forming the energy, atoms and eventually the stars and galaxies we see today. But to call this concept merely a theory is to misjudge the overwhelming amount of evidence. There are separate lines of evidence, each of which independently points towards this as the origin story for our Universe. The first came with the amazing discovery that almost all galaxies are moving away from us. In 1912, Vesto Slipher calculated the speed and direction of "spiral nebulae" by measuring the change in the wavelengths of light coming from them. He realized that most of them were moving away from us. We now know these objects are galaxies, but a century ago astronomers thought these vast collections of stars might actually be within the Milky Way. In 1924, Edwin Hubble figured out that these galaxies are actually outside the Milky Way. He observed a special type of variable star that has a direct relationship between its energy output and the time it takes to pulse in brightness. By finding these variable stars in other galaxies, he was able to calculate how far away they were. Hubble discovered that all these galaxies are outside our own Milky Way, millions of light-years away. So, if these galaxies are far, far away, and moving quickly away from us, this suggests that the entire Universe must have been located in a single point billions of years ago. The second line of evidence came from the abundance of elements we see around us. In the earliest moments after the Big Bang, there was nothing more than hydrogen compressed into a tiny volume, with crazy high heat and pressure. The entire Universe was acting like the core of a star, fusing hydrogen into helium and other elements. This is known as Big Bang Nucleosynthesis. As astronomers look out into the Universe and measure the ratios of hydrogen, helium and other trace elements, they exactly match what you would expect to find if the entire Universe was once a really big star. Line of evidence number 3: cosmic microwave background radiation. In the 1960s, Arno Penzias and Robert Wilson were experimenting with a 6-meter radio telescope, and discovered a background radio emission that was coming from every direction in the sky - day or night. From what they could tell, the entire sky measured a few degrees above absolute zero. Theories predicted that after a Big Bang, there would have been a tremendous release of radiation. And now, billions of years later, this radiation would be moving so fast away from us that the wavelength of this radiation would have been shifted from visible light to the microwave background radiation we see today. The final line of evidence is the formation of galaxies and the large scale structure of the cosmos. About 10,000 years after the Big Bang, the Universe cooled to the point that the gravitational attraction of matter was the dominant form of energy density in the Universe. This mass was able to collect together into the first stars, galaxies and eventually the large scale structures we see across the Universe today. These are known as the 4 pillars of the Big Bang Theory. Four independent lines of evidence that build up one of the most influential and well-supported theories in all of cosmology. But there are more lines of evidence. There are fluctuations in the cosmic microwave background radiation, we don't see any stars older than 13.8 billion years, the discoveries of dark matter and dark energy, along with how the light curves from distant supernovae. So, even though it's a theory, we should regard it the same way that we regard gravity, evolution and general relativity. We have a pretty good idea of what's going on, and we've come up with a good way to understand and explain it. As time progresses we'll come up with more inventive experiments to throw at. We'll refine our understanding and the theory that goes along with it. Most importantly, we can have confidence when talking about what we know about the early stages of our magnificent Universe and why we understand it to be true.
13:56
Add to Playlist
Watch Later Added
  • Key Facts
  • Actions
  • About This Video
  • 1 3:26

    The Earth is approximately 13.8 billion years old.

    Share Fact
  • 2 6:53

    The Big Bang Theory states the universe is extremely efficient, and expanded originally at a fantastic rate.

    Share Fact
  • 3 9:12

    Cosmic background radiation is like the "fingerprint of the universe" and can be heard in radio waves.

    Share Fact
CrashCourse is a fast, funny, irreverent look at history. In this episode, brothers John and Hank Green gives us their take on what makes Big History so darn important. Website: https://www.bighistoryproject.com/portal Facebook: https://www.facebook.com/bighistoryproject Twitter: https://twitter.com/BigHistoryPro
This video has a Smart Meme VIEW MEME