COSMOLOGY

Some scientists claim that dark energy is the biggest mystery in physics, that it is delicately fine tuned and unnatural, hence some special explanation is needed for it. Here Carlo Rovelli explains why he thinks they are wrong on all counts. Carlo Rovelli is one of the founders of loop quantum gravity. He is the Director of the quantum gravity group of the Centre de Physique Théorique (CPT) of the Aix-Marseille University and Chief Editor of Foundation of Physics. Carlo is also the author of best selling popular physics books such as "Seven brief lesson on physics "and "Reality Is not what it seems". To see more of our exclusive interviews with many of the world's leading physicists, subscribe to our channel or click here: https://www.youtube.com/watch?v=FVDJJVoTx7s&list=PLJ4zAUPI-qqqj2D8eSk7yoa4hnojoCR4m to read Carlo more detailed argument see here: https://arxiv.org/abs/1002.3966

Part 1: https://www.youtube.com/watch?v=B1le8JtBUx8 Part 2: https://www.youtube.com/watch?v=MNk87fP7hr8 Part 3: https://www.youtube.com/watch?v=s2VL5gS1rcg Full podcast episodes: http://www.askaspaceman.com Support: http://www.patreon.com/pmsutter Follow: http://www.twitter.com/PaulMattSutter and http://www.facebook.com/PaulMattSutter What was going in the very early universe? How does inflation provide the seeds of larger structures? How can we possibly test this? I discuss these questions and more in today’s Ask a Spaceman! Follow all the show updates at http://www.askaspaceman.com, and help support the show at http://www.patreon.com/pmsutter! Keep those questions about space, science, astronomy, astrophysics, and cosmology coming to #AskASpaceman for COMPLETE KNOWLEDGE OF TIME AND SPACE! Music by Jason Grady and Nick Bain.

The world’s premier astronomy and space science podcast. This episode of SpaceTime is brought to you by The Great Courses Plus. For a Free Trial with Unlimited Access to the entire The Great Courses Plus library use our URL and help support the show… www.thegreatcoursesplus.com/SPACE *Discrepancies continue to infect the standard model of cosmology Astronomers trying to work out how fast the universe is expanding -- still can’t agree on a key figure in the standard model of cosmology – known as the Hubble Constant. *The Highly Structured Outer Corona Scientists have discovered never-before-detected, fine-grained structures in the Sun's outer atmosphere, or corona. *New way to track space junk Astronomers are planning to use FM radio station signals to track space junk. *Dream Chaser getting ready for first cargo run to the space station A third operator is about to begin carrying cargo for NASA to the International Space Station. *The Science Report Omega 3 fats found in fatty fish makes little or no difference to your risk of cardiovascular events. Collapse of Antarctica’s Larsen C and George VI ice shelves could raise sea levels. Processed meats associated with manic episodes. New species of snake discovered on Australia’s Cape York Peninsula. The earliest bread ever baked discovered in north-eastern Jordan. For enhanced Show Notes including photos to accompany this episode, visit: http://www.bitesz.com/spacetimeshownotes Subscribe, rate and review SpaceTime at all good podcasting apps…including Apple Podcasts (formerly iTunes), Google Podcasts, Stitcher, PocketCasts, Podbean, Radio Public, TuneIn Radio, google play, Spreaker, Spotify, Deezer etc RSS feed: https://audioboom.com/channels/4642443.rss Would you prefer to have access to the special commercial-free version of SpaceTime? Help support the show, subscribe at Patreon....and share in the rewards. Details at www.patreon.com/spacetimewithstuartgary Help support SpaceTime: The SpaceTime with Stuart Gary merchandise shop. Get your T-Shirts, Coffee Cups, badges, tote bag + more and help support the show. Check out the range: http://www.cafepress.com/spacetime Thank you. Plus: As a part of the SpaceTime family, you can get a free audiobook of your choice, plus 30 days free access from audible.com. Just visit www.audibletrial.com/spacetime or click on the banner link at www.spacetimewithstuartgary.com Email: [email protected] Join our mailing list at http://www.bitesz.com/join-our-mailing-list Stream podcast episodes on demand from www.bitesz.com (mobile friendly).

Some of the highest-energy cosmic rays that reach Earth may originate in a star system 7,500 light-years away, according to a study published July 2 in Nature Astronomy.

Astronomers have finally found evidence to help solve the missing baryon problem, and they're pointing telescopes toward the Intergalactic Medium to figure it out. Hosted by: Hank Green For special, curated artifacts of this universe, check out https://scishowfinds.com/ ---------- Support SciShow by becoming a patron on Patreon: https://www.patreon.com/scishow ---------- Dooblydoo thanks go to the following Patreon supporters: Lazarus G, Sam Lutfi, Nicholas Smith, D.A. Noe, alexander wadsworth, سلطا الخليفي, Piya Shedden, KatieMarie Magnone, Scott Satovsky Jr, Charles Southerland, Bader AlGhamdi, James Harshaw, Patrick D. Ashmore, Candy, Tim Curwick, charles george, Saul, Mark Terrio-Cameron, Viraansh Bhanushali, Kevin Bealer, Philippe von Bergen, Chris Peters, Justin Lentz ---------- Like SciShow? Want to help support us, and also get things to put on your walls, cover your torso and hold your liquids? Check out our awesome products over at DFTBA Records: http://dftba.com/scishow ---------- Looking for SciShow elsewhere on the internet? Facebook: http://www.facebook.com/scishow Twitter: http://www.twitter.com/scishow Tumblr: http://scishow.tumblr.com Instagram: http://instagram.com/thescishow ---------- Sources: https://www.nature.com/articles/s41586-018-0204-1 http://www.esa.int/Our_Activities/Space_Science/XMM-Newton_finds_missing_intergalactic_material http://iopscience.iop.org/article/10.1088/0004-637X/759/1/23 http://iopscience.iop.org/article/10.1086/306025/ https://wwwmpa.mpa-garching.mpg.de/~komatsu/lecturenotes/Mike_Anderson_on_missing_baryons.pdf [PDF] https://arxiv.org/abs/1601.01260 https://arxiv.org/abs/1210.0544 http://www.helsinki.fi/~hkurkisu/cpt/Cosmo11 [PDF] https://arxiv.org/abs/astro-ph/9504082 https://wmap.gsfc.nasa.gov/universe/uni_matter.html http://iopscience.iop.org/article/10.1086/320548 http://iopscience.iop.org/article/10.1088/0004-637X/759/1/23/ https://arxiv.org/abs/0712.2375 https://arxiv.org/pdf/1607.01943.pdf [PDF] http://iopscience.iop.org/article/10.1086/427874/ Images: https://en.wikipedia.org/wiki/File:Ilc_9yr_moll4096.png https://en.wikipedia.org/wiki/File:WHIM.jpg https://commons.wikimedia.org/wiki/File:Ions.svg https://en.wikipedia.org/wiki/File:XMM-Newton_spacecraft_model.png https://en.wikipedia.org/wiki/File:Artist%27s_rendering_ULAS_J1120%2B0641.jpg https://svs.gsfc.nasa.gov/10663

What if dark matter isn’t the solution to space’s greatest mysteries? These are the alternative theories. There’s a New Form of Matter in Town: EXCITONIUM! - https://youtu.be/17Kvxe6v5Ms Read More: Does Dark Matter Exist? Bold New Study Offers Alternative Model https://www.space.com/39001-dark-matter-doesnt-exist-study-suggests.html “Dark matter is the elusive, invisible substance that appears to make up more than 80 percent of the total mass in the universe — far more than accounted for by the "regular" matter that makes up things like stars, planets and everything astronomers can directly observe. A new study makes the bold claim, however, that perhaps dark matter doesn't exist at all.” Astronomers Capture the First ‘Image' of the Dark Matter That Holds the Universe Together https://www.seeker.com/space/astronomy/astronomers-capture-the-first-image-of-the-dark-matter-that-holds-the-universe-together “Theories, computer models, and indirect observations have indicated that there is a cosmic web of dark matter that connects galaxies and constitutes the large-scale structure of the cosmos. But while the filaments that make up this web are massive, dark matter is incredibly difficult to observe.” Astronomers Found Two Massive Galaxies Amid an Ocean of Dark Matter https://www.seeker.com/astronomy/astronomers-found-two-massive-galaxies-amid-an-ocean-of-dark-matter “The discovery provides new details on the role that dark matter played in assembling large structures in the universe. Astronomers say the amount of dark matter that “clumped” in one area in order to create galaxies this large would have been quite rare. Now, researchers have produced what they say is the first composite image of a dark matter filament that connects galaxies together.” ____________________ Seeker inspires us to see the world through the lens of science and evokes a sense of curiosity, optimism and adventure. Visit the Seeker website https://www.seeker.com/videos Subscribe now! http://www.youtube.com/subscription_center?add_user=dnewschannel Seeker on Twitter http://twitter.com/seeker Trace Dominguez on Twitter https://twitter.com/tracedominguez Seeker on Facebook https://www.facebook.com/SeekerMedia/ Seeker http://www.seeker.com/ Special thanks to Athena Brensberger for writing and hosting this episode of Seeker! Check Athena out on Twitter: https://twitter.com/astroathens

Is String Theory the final solution for all of physic’s questions or an overhyped dead end? This video was realised with the help of Dr. Alessandro Sfondrini and it was funded by SNSF under Agora Grant n. 171622 and through the NCCR SwissMAP: The Mathematics of Physics. See also our video on the black-hole information paradox: https://bit.ly/2DU6p8P Kurzgesagt Newsletter: http://eepurl.com/cRUQxz Support us on Patreon so we can make more videos (and get cool stuff in return): https://www.patreon.com/Kurzgesagt?ty=h Kurzgesagt merch: http://bit.ly/1P1hQIH Facebook: http://bit.ly/1NB6U5O Twitter: http://bit.ly/2DDeT83 Instagram: http://bit.ly/2DEN7r3 Discord: https://discord.gg/Fsstncs The music of the video here: Soundcloud: http://bit.ly/2CsAbob Bandcamp: http://bit.ly/2oHsSPZ Facebook: http://bit.ly/2qW6bY4 THANKS A LOT TO OUR LOVELY PATRONS FOR SUPPORTING US: Flavio Storino, Alice Balcon, Hari Krishnan, Warren Wiscombe, Sara Zeglin, Asiryan Alexander, maarten sprengers, William Northern, Kerem Mimaroglu, Yana Kultysheva, Josh, Keaton Anderson, Croconaw, Peter Steinberger, Jonathan Diamond, Troy McConaghy, Paddy, Darko Sperac, Peter Burkhalter, Chris Amaris, Tyler Lovell, John Ruble, Chase Henson, Arpita Singh, Edward C.P., Andreas Edlund, Ryan Bubinski, Paul Greyson, Jerry Ding, Austin Sundquist, Daniel Link, Tim Johnson, kayleigh dreste, Johan Sjöblom, Max Stuart, Mush Rain, Andor Baranyi, Eduardas Afanasjevas, Bill Clem, Jake Smith, Stephen Woerner, Jeff Sorensen, Christopher Damsgaard, Eduardo AV, Michael Gawenka, Florian Hoedt, Lucas Nyman, Nathanael Baker, Martin Wierzyk, Mauricio Streb, Karl, Rameet Chawla, Joachim Andersen, Avinash, Erik Golden, Glenn Stoltz, Elliott Nelson, Andrew Averett, Ben Wei Help us caption & translate this video! http://www.youtube.com/timedtext_cs_p... String Theory Explained – What is The True Nature of Reality?

How old is the universe, and how did it begin? Throughout history, countless myths and scientific theories have tried to explain the universe's origins. The most widely accepted explanation is the big bang theory. Learn about the explosion that started it all and how the universe grew from the size of an atom to encompass everything in existence today. ➡ Subscribe: http://bit.ly/NatGeoSubscribe About National Geographic: National Geographic is the world's premium destination for science, exploration, and adventure. Through their world-class scientists, photographers, journalists, and filmmakers, Nat Geo gets you closer to the stories that matter and past the edge of what's possible. Get More National Geographic: Official Site: http://bit.ly/NatGeoOfficialSite Facebook: http://bit.ly/FBNatGeo Twitter: http://bit.ly/NatGeoTwitter Instagram: http://bit.ly/NatGeoInsta Origins of the Universe 101 | National Geographic https://youtu.be/HdPzOWlLrbE National Geographic https://www.youtube.com/natgeo

Cosmologists have detected a signal from the cosmic dawn - the period where the first stars came into existence. But how did they do it and what might this mean for our understanding of the Universe? Nature physics reporter, Elizabeth Gibney, talks us through the finding.

Support the show: http://www.patreon.com/pmsutter All episodes: http://www.AskASpaceman.com What did Hubble really discover? Why does redshift imply an expanding universe? Why is the night sky dark? Why is there so much hydrogen, and how is that connected to the Big Bang? I discuss these questions and more in today’s Ask a Spaceman! Support the show: http://www.patreon.com/pmsutter All episodes: http://www.AskASpaceman.com Follow on Twitter: http://www.twitter.com/PaulMattSutter Like on Facebook: http://www.facebook.com/PaulMattSutter Watch on YouTube: http://www.youtube.com/PaulMSutter Go on an adventure: http://www.AstroTours.co Keep those questions about space, science, astronomy, astrophysics, physics, and cosmology coming to #AskASpaceman for COMPLETE KNOWLEDGE OF TIME AND SPACE! Big thanks to my top Patreon supporters this month: Robert R., Justin G., Matthew K., Kevin O., Justin R., Chris C., Helge B., Tim R., SkyDiving Storm Trooper, Steve P., Lars H., Khaled T., John F., Mark R., and David B.! Music by Jason Grady and Nick Bain. Thanks to WCBE Radio for hosting the recording session, Greg Mobius for producing, and Cathy Rinella for editing. Hosted by Paul M. Sutter, astrophysicist at The Ohio State University, Chief Scientist at COSI Science Center, and the one and only Agent to the Stars (http://www.pmsutter.com).

A discussion of various theories for the End of the Universe. Watch part 2 here: https://www.youtube.com/watch?v=XLTb0V1BGNw How the Universe began and why is a question that's obsessed humanity for at least as long as civilization has existed, at the same time, how it will end has equally fascinated us. Today we are joined by Astrophysicist Paul Sutter for a two-part episode looking at the science and history of how the Universe came to be and may end. Support the Channel on Patreon: https://www.patreon.com/IsaacArthur Visit our Website: http://www.isaacarthur.net Join the Facebook Group: https://www.facebook.com/groups/1583992725237264/ To help us grow your SFIA community, follow https://twitter.com/Isaac_A_Arthur on Twitter and RT our future content. Visit the sub-reddit: https://www.reddit.com/r/IsaacArthur/ Listen or Download the audio of this episode from Soundcloud: https://soundcloud.com/isaac-arthur-148927746/the-compendium-of-doom Cover Art by Jakub Grygier: https://www.artstation.com/artist/jakub_grygier Graphics Team: Edward Nardella Jeremy Jozwik Jarred Eagley Justin Dixon Jeremy Jozwik Katie Byrne Kris Holland/Mafic Studios: http://www.maficstudios.com Luuk Warringa Misho Yordanov Murat Mamkegh Nick Talmers Nieuwoudt Pierre Demet Sergio Botero Stefan Blandin Script Editing: Andy Popescu Connor Hogan Edward Nardella Eustratius Graham Gregory Leal Jefferson Eagley Keith Blockus Luca de Rosa Mark Warburton Michael Gusevsky Mitch Armstrong MolbOrg Naomi Kern Philip Baldock Sigmund Kopperud Steve Cardon Tiffany Penner Music: Markus Junnikkala, "Leaving the Galaxy" Miguel Johnson, "So Many Stars" Aerium, "Fifth Star of Aldebaran" A.J. Prasad, "Aether"

WATCH PART 1: https://youtu.be/rpA-Bd0d6kw This is Part 2 of a collab series with Isaac Arthur. How will the universe end, and how is it connected to the mysterious dark energy? Support: http://www.patreon.com/pmsutter Follow: http://www.twitter.com/PaulMattSutter and http://www.facebook.com/PaulMattSutter

Stream on demand from www.bitesz.com (mobile friendly). SpaceTime 20180105 Series 21 Episode 02 *Solving the mystery of what came first? Astronomers may be a step closer to solving one of the greatest mysteries in astrophysics – which came first the galaxy – or the supermassive black hole at its centre. The problem is do galaxies form first from the accumulation of stars, globular clusters, and molecular gas and dust clouds -- with densities at the galactic centre eventually becoming so high it forms a black hole. *Supermassive black hole stellar factory Astronomers have discovered 11 newly formed infant protostars within three light years of the supermassive black hole at the centre of our galaxy. Black holes generate powerful gravitational tidal forces and intense ultraviolet and X-ray radiation – environments far more conducive to destroying stars rather than creating them. *Mars may not be as dry as it seems A new study suggests water on Mars is being absorbed by the red planet’s rocks like a sponge. The findings reported in the journal Nature suggest that Martian basalt rocks can hold up to 25 percent more water than similar basalts on Earth. *SpaceX to launch Falcon Heavy shortly After more than 12 years of planning and development Space X is finally getting ready to fly its new Falcon Heavy launch vehicle. The 70-metre-tall reusable rocket is based around three Falcon 9 common booster core stages -- mounted side by side in a similar fashion to the Delta 4 heavy -- from which it will take the title as the world’s most powerful operational launch vehicle. For enhanced Show Notes including photos to accompany this episode, visit: http://www.bitesz.com/spacetimeshownotes Subscribe, rate and review SpaceTime at all good podcasting apps…including Apple Podcasts (formerly iTunes), audioBoom, Stitcher, PocketCasts, Podbean, Radio Public, Tunein Radio, google play, Spreaker etc RSS feed: https://audioboom.com/channels/4642443.rss Would you prefer to have access to the special commercial free version of SpaceTime? Help support the show, subscribe at Patreon....and share in the rewards. Details at www.patreon.com/spacetimewithstuartgary Help support SpaceTime : The SpaceTime with Stuart Gary merchandise shop. Get your T-Shirts, Coffee Cups, badges, tote bag + more and help support the show. Check out the range: http://www.cafepress.com/spacetime Thank you. Plus: As a part of the SpaceTime family, you can get a free audio book of your choice, plus 30 days free access from audible.com. Just visit www.audibletrial.com/spacetime or click on the banner link at www.spacetimewithstuartgary.com Email: [email protected] Join our mailing list at http://www.bitesz.com/join-our-mailing-list For more, follow SpaceTime on Facebook, twitter, Tumblr, YouTube, Instagram, Google+, Patreon and Spreaker: Facebook: @spacetimewithstuartgary twitter: @stuartgary Tumblr: http://spacetimewithstuartgary.tumblr.com/ Instagram: https://www.instagram.com/spacetimewithstuartgary/ Google+: https://plus.google.com/u/2/collection/cabtNB YouTube: https://www.youtube.com/playlist?list=PLhpBkuHSLfIRnliLB12HoC1QE0rwr8qRS Patreon: https://www.patreon.com/spacetimewithstuartgary Spreaker: https://www.spreaker.com/show/spacetime-with-stuart-gary-2017 If you're enjoying SpaceTime, please help out by sharing and telling your friends. The best recommendation I can get is one from you. Thank you…

In this QA episode, Fraser wonders when the Big Rip might happen, could there be binary galaxies, what it would be like to live in higher gravity. Get your Year in Space 2018 Calendar http://www.yearinspace.com Get an email announcement whenever we release a new video: http://eepurl.com/dcThQ5 What Fraser's Watching Playlist: https://www.youtube.com/playlist?list=PLbJ42wpShvmkjd428BcHcCEVWOjv7cJ1G Support us at: http://www.patreon.com/universetoday More stories at: http://www.universetoday.com/ Follow us on Twitter: @universetoday Like us on Facebook: https://www.facebook.com/universetoday Google+ - https://plus.google.com/+universetoday/ Instagram - http://instagram.com/universetoday Team: Fraser Cain - @fcain / [email protected] Karla Thompson - @karlaii / https://www.youtube.com/channel/UCEItkORQYd4Wf0TpgYI_1fw Chad Weber - [email protected] Chloe Cain - Instagram: @chloegwen2001

Dark matter is the mysterious and pervasive substance that constitutes most — about 85% — of the matter in our Universe. Although scientists have made progress in better understanding dark matter, the true nature of this invisible material remains elusive. NASA's Chandra X-ray Observatory plays an important role in the search to learn about dark matter. One way that astronomers have used Chandra to investigate dark matter has been through the study of a mysterious signal seen in the X-ray data. In 2014, astronomers reported they found a spike of intensity at a very specific energy in Chandra and XMM-Newton observations of the hot gas in the Perseus and other galaxy clusters. This spike, or emission line, is at an energy of 3.5 kiloelectron volts, or keV (pronounced "kay-ee-vee"), and could not easily be explained as emission from known elements. Therefore, one possibility was that this line was produced by dark matter particles. Naturally, determining the true nature of dark matter would be a huge discovery. And as Carl Sagan famously said, extraordinary claims require extraordinary evidence. Therefore, astronomers have been working hard both to replicate the initial results and also provide explanations for all of the observations connected to this original finding. Now a new team of astronomers has provided an innovative interpretation of the observations surrounding this 3.5 keV line. They propose that there is another mechanism at work, namely the absorption of X-ray light by mystery particles. If this is true, then it's possible that the 3.5 keV line may, in fact, be produced by dark matter particles. While these ideas need to be confirmed with future observations, it may be that the prospect of determining the nature of the darkest of matter may never have been more so bright.

In order to get the large scale structure of the Universe we see today, cosmologists have proposed the idea of inflation, that the Universe expanded an enormous amount in the earliest moments. But if inflation really happened, then it has even stranger implications for the nature of the Universe and the search for multiverses. Ethan Siegel https://www.patreon.com/startswithabang/ Treknology https://www.amazon.com/Treknology-Science-Star-Tricorders-Drive/dp/0760352631 Playlist Link: https://www.youtube.com/playlist?list=PLbJ42wpShvmnnhuiEaxjmvNkcujvNqNVs Support us at: http://www.patreon.com/universetoday More stories at: http://www.universetoday.com/ Follow us on Twitter: @universetoday Like us on Facebook: https://www.facebook.com/universetoday Google+ - https://plus.google.com/+universetoday/ Instagram - http://instagram.com/universetoday Team: Fraser Cain - @fcain / [email protected] Karla Thompson - @karlaii / https://www.youtube.com/channel/UCEItkORQYd4Wf0TpgYI_1fw Chad Weber - [email protected] Chloe Cain - Instagram: @chloegwen2001 We’ve covered the topic of inflation a couple of times in the past, but I’ll give you the short version one more time. The Big Bang exquisitely explains the expansion of the Universe we see today. When we look out as far as we can, to the edge of the observable Universe we see the afterglow of the Big Bang: the cosmic microwave background radiation. This light was released the moment the Universe had cooled down a little, and has been traveling for almost 13.8 billion years to reach us. Thanks to the expansion of the Universe, it’s been redshifted to just a few degrees above absolute zero. When astronomers measure the temperature of this background, it’s incredibly consistent, with only tiny fluctuations measurable with the most sensitive instruments. This means that the entire Universe that we can see had time to transfer temperature to each other before it expanded. But the original Big Bang Theory suggests that the expansion of the Universe didn’t give the material time to even out its temperature. In order to explain this, cosmologists developed the concept of inflation. There was a period in the earliest Universe when the energy in matter was bound up in the fabric of space itself. The Universe expanded so quickly, that a region the size of a subatomic particle would have been stretched to the size of the visible Universe in a fraction of a second. Inflation also answered other challenges that the original Big Bang couldn’t explain, such as the flatness of the Universe, and total lack of monopoles. Like I said, we’ve done a whole video about inflation. But inflation has introduced its own set of strange ideas, including the concept of “eternal inflation”; that inflation didn’t end for the entire Universe like it did in our local area. There are regions undergoing inflation all over the place, creating multiple universes within our Universe. You know, a multiverse. I’ll be honest, though, the concept of eternal inflation is beyond my comprehension. And so, in times like this, I like to bring in a ringer. Today, I’m glad to bring you Dr. Ethan Siegel, an astrophysicist and science writer. His most recent book is Treknology, all about the science of Star Trek. Ethan tackles some of the most complex topics out there in an understandable way, and I could really use his help.

In order to get the large scale structure of the Universe we see today, cosmologists have proposed the idea of inflation, that the Universe expanded an enormous amount in the earliest moments. But if inflation really happened, then it has even stranger implications for the nature of the Universe and the search for multiverses. Ethan Siegel https://www.patreon.com/startswithabang/ Treknology https://www.amazon.com/Treknology-Science-Star-Tricorders-Drive/dp/0760352631 Playlist Link: https://www.youtube.com/playlist?list=PLbJ42wpShvmnnhuiEaxjmvNkcujvNqNVs Support us at: http://www.patreon.com/universetoday More stories at: http://www.universetoday.com/ Follow us on Twitter: @universetoday Like us on Facebook: https://www.facebook.com/universetoday Google+ - https://plus.google.com/+universetoday/ Instagram - http://instagram.com/universetoday Team: Fraser Cain - @fcain / [email protected] Karla Thompson - @karlaii / https://www.youtube.com/channel/UCEItkORQYd4Wf0TpgYI_1fw Chad Weber - [email protected] Chloe Cain - Instagram: @chloegwen2001 We’ve covered the topic of inflation a couple of times in the past, but I’ll give you the short version one more time. The Big Bang exquisitely explains the expansion of the Universe we see today. When we look out as far as we can, to the edge of the observable Universe we see the afterglow of the Big Bang: the cosmic microwave background radiation. This light was released the moment the Universe had cooled down a little, and has been traveling for almost 13.8 billion years to reach us. Thanks to the expansion of the Universe, it’s been redshifted to just a few degrees above absolute zero. When astronomers measure the temperature of this background, it’s incredibly consistent, with only tiny fluctuations measurable with the most sensitive instruments. This means that the entire Universe that we can see had time to transfer temperature to each other before it expanded. But the original Big Bang Theory suggests that the expansion of the Universe didn’t give the material time to even out its temperature. In order to explain this, cosmologists developed the concept of inflation. There was a period in the earliest Universe when the energy in matter was bound up in the fabric of space itself. The Universe expanded so quickly, that a region the size of a subatomic particle would have been stretched to the size of the visible Universe in a fraction of a second. Inflation also answered other challenges that the original Big Bang couldn’t explain, such as the flatness of the Universe, and total lack of monopoles. Like I said, we’ve done a whole video about inflation. But inflation has introduced its own set of strange ideas, including the concept of “eternal inflation”; that inflation didn’t end for the entire Universe like it did in our local area. There are regions undergoing inflation all over the place, creating multiple universes within our Universe. You know, a multiverse. I’ll be honest, though, the concept of eternal inflation is beyond my comprehension. And so, in times like this, I like to bring in a ringer. Today, I’m glad to bring you Dr. Ethan Siegel, an astrophysicist and science writer. His most recent book is Treknology, all about the science of Star Trek. Ethan tackles some of the most complex topics out there in an understandable way, and I could really use his help.

For years, astronomers have been unable to find up to half of the baryonic matter in the universe. We may just have solved this problem. You can further support us on Patreon at https://www.patreon.com/pbsspacetime Get your own Space Time t­shirt at http://bit.ly/1QlzoBi Tweet at us! @pbsspacetime Facebook: facebook.com/pbsspacetime Email us! pbsspacetime [at] gmail [dot] com Comment on Reddit: http://www.reddit.com/r/pbsspacetime Help translate our videos! https://www.youtube.com/timedtext_cs_panel?tab=2&c=UC7_gcs09iThXybpVgjHZ_7g Previous Episode: The Nature of Nothing | Space Time https://www.youtube.com/watch?v=X5rAGfjPSWE&t=55s Dark Matter! https://youtu.be/z3rgl-_a5C0 Dark Energy Playlist https://youtu.be/xZTb6sfHEX8?list=PLsPUh22kYmNA6WUmOsEEi32zi_RdSUF4i We’ve known for some time that around 95% of the energy content of the universe is in dark matter and dark energy. This dark sector doesn’t interact with light in any way and so is invisible to us. The remaining 5% - the light sector – represents all of the regular matter in the universe. Yet what if I told you that all of the stars and galaxies and galaxy clusters only comprise 10% of the light sector. The rest has proved as elusive as the dark sector. We think it must exist as extremely diffuse gas in between the galaxies, yet our intense searches miss up to half of it. At least until now. Resources Graaff et al. 2017, "Missing Baryons in the Cosmic Web Revealed by the Sunyaev-Zel'dovich Effect" https://arxiv.org/abs/1709.10378v1 Tanimura et al. 2017, "A Search for Warm/Hot Gas Filaments Between Pairs of SDSS Luminous Red Galaxies" https://arxiv.org/abs/1709.05024 Written and Hosted by Matt O'Dowd Produced by Rusty Ward Graphics by Kurt Ross Assistant Editing and Sound Design by Mike Petrow Made by Kornhaber Brown (www.kornhaberbrown.com) Special thanks to our Patreon Big Bang, Quasar and Hypernova Supporters: Big Bang BITISM CoolAsCats David Nicklas Richard Senegor Quasar Tambe Barsbay Mayank M. Mehrota Mars Yentur Mark Rosenthal Dean Fuqua Y2 Justin Lloyd Hypernova Edmund Fokschaner Max Levine Matthew O’Connor Eugene Lawson Barry Hatfield Martha Hunt Joseph Salomone Chuck Zegar Craig Peterson Jordan Young Ratfeast John Hofmann Thanks to our Patreon Gamma Ray Burst Supporters: Denys Ivanov Nick Virtue Alexey Eromenko Nicholas Rose Scott Gossett Mark Dykstra Peter Durocher Michael Kers Chris Hicks Mark Vasile Patrick Murray Sultan Alkhulaifi Alex Seto Michal-Peanut Karmi Erik Stein Daniel Lyons Kevin Warne JJ Bagnell J Rejc Amy Jie Avi Goldfinger John Pettit Shannan Catalano Florian Stinglmayr Yubo Du Benoit Pagé-Guitard Nathan Leniz Jessica Fraley Loro Lukic Brandon Labonte David Crane Greg Weiss

Computer modeling we do of our Universe suggested that half of the visible matter in the Universe was "missing", we couldn't account for the discrepancy between what's observed in our Universe and what's modeled in computers using the laws of physics our Universe is governed by. Does that mean that our physics is incorrect, or were we just looking in all the wrong places? Turns out, we were looking in the wrong places. === CONTINUE THE CONVERSATION === Twitter.com/TMRO Facebook.com/TMROTV YouTube.com/TMRO Reddit.com/r/tmro Twitch.tv/TMRO TMRO.tv === OUR REAL-TIME DISCORD CHANNEL === All of the TMRO Shows are created and maintained in our Discord channel. Escape Velocity Patrons have access to a special room, but we also have free #general rooms that anyone can participate in. Join in for free at https://discord.gg/9NkkFWD === TMRO IS CROWD FUNDED === TMRO:Space is a crowd funded show. If you like this episode consider contributing to help us to continue to improve. Head over to http://www.patreon.com/tmro for information plus our all new goals and reward levels

Recent findings suggest that the fundamental constants might not be as stable as we assumed. And be sure to signup for your free trial of The Great Courses Plus at http://ow.ly/rcsA30beNw1 You can further support us on Patreon at https://www.patreon.com/pbsspacetime Get your own Space Time t­shirt at http://bit.ly/1QlzoBi Tweet at us! @pbsspacetime Facebook: facebook.com/pbsspacetime Email us! pbsspacetime [at] gmail [dot] com Comment on Reddit: http://www.reddit.com/r/pbsspacetime Help translate our videos! https://www.youtube.com/timedtext_cs_... Previous Episode: The Future of Space Telescopes https://www.youtube.com/watch?v=kL81uuYW9BY&t=40s Webb et al. 1998, A Search for Time Variation of the Fine Structure Constant https://arxiv.org/abs/astro-ph/9803165 Webb et al. 2011, A Search for Time Variation of the Fine Structure Constant https://arxiv.org/abs/1008.3907 Martins & Pinho 2016, Stability of Fundamental Couplings: a Global Analysis https://arxiv.org/abs/1701.08724 The laws of physics are the same everywhere in the universe. At least we astrophysicists hope so. After all, it’s hard to unravel the complexities of distant parts of the universe if we don’t know the basic rules. But what if this is wrong? There is a hint of evidence that the fundamental constants that govern our universe may evolve over time, and even from one location to another. Written by Graeme Gossel and Matt O’Dowd Hosted by Matt O'Dowd Produced by Rusty Ward Graphics by Kurt Ross Assistant Editing and Sound Design by Mike Petrow Made by Kornhaber Brown (www.kornhaberbrown.com) Special thanks to our Patreon Big Bang, Quasar and Hypernova Supporters: Big Bang BITISM CoolAsCats David Nicklas Richard Senegor Quasar Tambe Barsbay Meo Meow Oink Oink Mayank M. Mehrota Mars Yentur Mark Rosenthal Dean Fuqua Hypernova Max Levine Edmund Fokschaner Eugene Lawson Chuck Zegar Jordan Young Ratfeast John Hofmann Joseph Salomone Martha Hunt Craig Peterson Barry Hatfield Matthew O’Connor Thanks to our Patreon Gamma Ray Burst Supporters: Scott Gossett Mark Dykstra Peter Durocher Michael Kers Chris Hicks Mark Vasile Patrick Murray Sultan Alkhulaifi Alex Seto Michal-Peanut Karmi Bernardo Higuera Erik Stein Daniel Lyons Kevin Warne JJ Bagnell J Rejc Amy Jie Avi Goldfinger John Pettit Shannan Catalano Florian Stinglmayr Yubo Du Benoit Pagé-Guitard Nathan Leniz Jessica Fraley Loro Lukic Brandon Labonte David Crane Greg Weiss The Great Courses Plus is currently available to watch through a web browser to almost anyone in the world and optimized for the US market. The Great Courses Plus is currently working to both optimize the product globally and accept credit card payments globally.

Thanks to astronomer Edwin Hubble and others, scientists have known since 1929 that our universe is expanding. Its current rate of expansion is called Hubble’s Constant (H0). There are two leading ways to measure H0, and for fifteen years, they more or less agreed with one another. Not anymore, and that’s a big deal. Here’s why. In the “Standard Model of Cosmology,” H0 is a crucial ingredient, right up there with the speed of light. H0 factors into everything we know about the universe: how old it is, how big it is, what it’s made of... If H0 is ‘tweaked’, we get a different age of the universe, different relative amounts of matter, dark matter, dark energy, and so on. Unlike the speed of light, however, scientists can’t measure H0 in the laboratory. Instead, H0 has to be inferred from observations of the universe. One way scientists have measured H0 is to use observations of type 1a supernovae combined with their host galaxies redshifts. Each 1a supernova releases roughly the same amount of light when it explodes. Measuring the amount of light we receive from a 1a supernova tells us its distance. Measuring an object’s redshift, or its increase in wavelength, tells us how fast that object is moving away from Earth. Researchers use many 1a supernovae as distance markers, measuring objects in our local universe then moving out to get a measurement of the universe’s rate of expansion. The other H0 measurement technique looks at the Cosmic Microwave Background (CMB) -- the “afterglow” from the Big Bang itself. The early universe was hot and dense, light couldn’t travel freely through space. As the universe cooled, the photons were released. This radiation left an imprint, providing insights into the composition of the universe at that time. The CMB can be used to make measurements from the early universe such as the density of dark matter and dark energy. Those measurements can be combined with the model of the evolution of the universe, allowing researchers to infer the rate of expansion of the universe, or Hubble’s Constant. As these two camps have improved their abilities to measure H0, it has become clear that they disagree. A recent study using the first method yielded an 8% greater expansion rate than the second method’s result. Now scientists are asking: Are we missing something? Wendy Freedman, Sullivan professor of astronomy and astrophysics at the University of Chicago says, “It could be that we don’t understand the uncertainties well enough to know why these two methods differ.” Freedman led a 2001 study using the Hubble Space Telescope to measure H0 via the first method, and is leading a new project to measure it more accurately. Another intriguing question: Is it incorrect to expect agreement in these measurements of H0? Maybe the Standard Model of Cosmology, which predicts agreement, is wrong. That would send researchers on an exciting search for a new model of the cosmos. “Do we really know what makes up all of the radiation in the Big Bang?” wonders Freedman. “Is there a new kind of particle we aren’t accounting for? Or are dark energy’s or dark matter’s properties changing over time? Over the next few years, researchers like Freedman will be trying to poke holes in how each method conducts its analysis -- before possibly invoking a revised model of cosmology. Credit: NASA science.nasa.gov.

SUBSCRIBE to Space with Sarah: http://tinyurl.com/k5wxw6x Did the Big Bang really create our Universe? What is the evidence of Big Bang? In this episode of Space with Sarah astrophysicist, Sarah, explains how the cosmic microwave background, the expansion of space and the fraction of Helium in our Universe fits in very nicely with our theory stating that the entire Universe being created ~13.8 billion years ago. There is also a lot of other evidence not presented in this video. For example the ages of the oldest White Dwarfs. Creator: Sarah Pearson Producer: Brett Van Deusen Animator: Joshua Bogy Image credits: NASA The Illustris Project: http://www.illustris-project.org/ Via Lactea II - Diemand et al. 2008, Nature Digital graphics by Morgan Mullen Episode music by Krychek: http://krychek.nyc Episode background: Via Lactea II simulation by Diemand, Kuhlen, Madau et al. 2008, Nature Intro graphics by Frederik Olufsen: http://thefrederik.com/portfolio/ Intro Music by Palm Tree Gang & Max Fail (courtesy of Riotville Records): https://soundcloud.com/riotville-records/palm-tree-gang-max-fail-chameleon-feat-anuka Sound design by Tim Korn Dungeon Beach: http://dungeonbeach.com/ Color correction: Jeff Sousa Partially supported by the National Science Foundation: NSF grant AST-1614743

Text at http://howfarawayisit.com/documents/ This is part one of a two part series on the Big Bang theory. Here we cover the foundational concepts used in the standard model we cover in part 2. We start out with the basic Cosmological Principle for an isotropic and homogeneous Universe. We then review Hubble’s Law that came from the discovery that the Universe was expanding. We go into some depth to illustrate what expanding space is and how it impacts the basic idea of ‘distance’. This includes a definition of Cosmic Distance and how it leads to the Visible Horizon. We then develop a concept of how the Universe’s expansion would work using Newton’s gravitational theory including his Shell Theorem. We use this to define a cosmic scale factor and use it to see what happens in a matter dominated Universe. We then expand that to include a radiation dominated Universe. With the Newtonian mechanics view in hand, we update to Friedmann’s equation based on Einstein’s General Theory of Relativity along with the Equation of State. We examine the impact of flat, spherical and hyperbolic space on the cosmic sale factor, and identify the Critical Energy Density needed in order to have flat space. We end with a look at cosmological redshift, and an observation on galaxy counts that lead to the conclusion that we exist in flat space-time. Music: @00:00 Puccini, Giacomo: Che gelida manina - what a cold little hand La Boheme Act I: Rodolfo's Aria - "Che gelida manina" (Instrumental Version), Sofia Philharmonic Orchestra; from the album “100 Must-Have Opera Karao-ke” 2015 @04:34 Beethoven, Ludwig van: Piano Concerto No. 2 in B-Flat Major, Op. 19: II. Adagio; Anton Dikov, Sofia Philharmonic Orchestra; from the album “50 Must-Have Adagio Masterpieces” 2013 @09:41 Borodin, Alexander: Polovetsian Dances from Price Igor; London Philharmonic Orchestra; from the album “The Greatest Classical Masterpieces! (Digitally Remastered)” 2008 @13:26 Tchaikovsky, Pyotr Ilyich: Waltz from Sleeping Beauty from the al-bum Tchaikovsky Peter Ilyich 2009 @16:37 Schubert, Franz: Music to Rosamunde, D. 797_ Ballet Music No. 1_ II. Andante un poco assai; Hermitage Museum Orchestra and Alexander Ti-tov; from the album “Schubert - 100 Supreme Classical Masterpieces: Rise of the Masters” 2011 @22:24 Offenbach, Jacques: Barcarolle (from Tales of Hoffman); from the al-bum “A Calendar of Classics - July” 2007 @25:40 Bach, Johann Sebastian: Double Violin Concerto; Anne-Sophie Mut-ter, English Chamber Orchestra, Salvatore Accardo; from the album “Essential Adagios” 2010 @33:00 Rimsky-Korsakov: Scheherazade, II, Lento; Berliner Philharmoniker, from the album “Rimsky-Korsakov Greatest Hits” 2005

Text at http://howfarawayisit.com/documents/ We begin with the discovery of the Cosmic Microwave Background (CMB) radiation. We cover Recombination, Decoupling, and the Surface of Last Scattering that created the CMB. We examine the nature of the CMB temperature Anisotropy and how, through a process known as Caustics, it lead to galaxy filaments and great voids. This analysis includes Cold Dark Matter. We then cover Vacuum Energy, the Casimir Effect and Dark Energy. We then cover the observational evidence for an Accelerating expansion. We then go beyond the surface of last scattering to Neutrino Decoupling, Nucleosynthesis, Baryogenesis and Cosmic Inflation. We summarize with a review of the cosmic time line, and conclude with a look at current and future cosmology research. Music @00:00 Bach, Johann Sebastian: Wachet auf, ruft uns die Stimme, BWV 645 ('Sleepers, awake'); Raymond Agoult and The New Symphony Orchestra of London – from the album “Essential Bach (2CDs)” 2000 @04:46 Offenbach, Jacques: Barcarolle (from Tales Of Hoffman); from the album “A Calendar Of Classics - July” 2007 @09:00 Strauss II, Johann: Waltz on the Beautiful Blue Danube, Op. 314; Pe-ter Guth & Royal Philharmonic Orchestra, from the album “Strauss: Emperor Waltz, Waltz on the Beautiful Blue Danube, Overture to Die Fleidermaus” 1998 @15:05 Bach, Johann Sebastian: Concerto for Violin, Strings and Continuo in E Major, BWV 1042: II. Adagio; Christian Altenburger, German Bach Solo-ists, from the album “50 Must-Have Adagio Masterpieces” 2013 @21:22 Beethoven, Ludwig van: “The Emperor” Adagio from Piano Concerto No.5 in E Flat Major. Op.73 ''The Emperor''; Julia Thornton, from the album “Essential Adagios” 2010 @27:56 Mozart, Wolfgang Amadeus: Symphony No.8 in D, K.48 - 2. Andan-te; Academy of St. Martin in the Fields and Sir Neville Marriner; from the al-bum “Mozart: The Symphonies, Vol.1 (Complete Mozart Edition)” @36:21 Puccini, Giacomo: Turandot, Act III: Calaf's Aria - "Nessun dorma" - none shall sleep; (Instrumental Version); Sofia Philharmonic Orchestra; from the album “100 Must-Have Opera Karaoke” 2015 @39:52 Nicolai, Otto: Moon Choir (from The Merry Widows Of Windsor); Otto Nicolai & Bulgarian National Choir, Sofia Philharmonic Orchestra, from the album “66 Must-Have Sensual Classics” 2011

The experiments based at the Large Hadron Collider in Switzerland are undergoing a constant series of upgrades. Fermilab scientists Steve Nahn and Vivian O’Dell lead these upgrade efforts in the United States.

Support ASTRONOMIC: https://www.patreon.com/Astronomic PayPal Donations: [email protected] Subscribe to ASTRONOMIC: https://www.youtube.com/astronomic1 Twitter: https://www.twitter.com/astronomic1 Instagram: https://www.instragram.com/astronomic1 Facebook: https://www.facebook.com/astronomicbook Exclusive Content: https://www.curious.com/astronomic Hello Everyone! Welcome to OUR Universe! If you've enjoyed the video... click the LIKE button! If you want to support the channel... click the SUBSCRIBE button! TITLE: How To Measure The Distances To The Stars LINKS: 1. Parallax (Wiki) https://en.wikipedia.org/wiki/Parallax 2. Standard-candle supernovae (Astronomy.com) http://www.astronomy.com/news/2014/03/standard-candle-supernovae-are-still-standard-but-why 3. Hubble Law - Redshift (Wiki) https://en.wikipedia.org/wiki/Hubble%27s_law#Combining_redshifts_with_distance_measurements OTHER VIDEOS: 1. What Is Redshift? https://www.youtube.com/watch?v=ikgRZt1BSyk 2. The Lifetime Of A Star https://www.youtube.com/watch?v=1UGBeedYuF4 3. Does The Moon Spin? https://www.youtube.com/watch?v=MrzWzMUhQfw Thanks for Watching! Twitter: https://www.twitter.com/astronomic1 Instagram: https://www.instragram.com/astronomic1 Facebook: https://www.facebook.com/astronomicbook Exclusive Content: https://www.curious.com/astronomic Support ASTRONOMIC: https://www.patreon.com/Astronomic PayPal Donations: [email protected] Subscribe to ASTRONOMIC: https://www.youtube.com/astronomic1

Our universe is racing toward its destruction as we speak. The end is not going to be especially pleasant, but when that end will happen is still a point of contention amongst cosmologists. Tech Insider tells you all you need to know about tech: gadgets, how-to's, gaming, science, digital culture, and more. Subscribe to our channel and visit us at: http://www.businessinsider.com/sai TI on Facebook: https://www.facebook.com/techinsider TI on Instagram: https://www.instagram.com/tech_insider/ TI on Twitter: https://twitter.com/techinsider

How big is the universe? Achieving the ability to explore our universe may be the biggest challenging humans will ever face. The extreme vastness of space makes it incredibly difficult to know what exists throughout our universe, but just how big is it? Watch the video to learn more. If you enjoyed the video please hit that like button. Also, remember to subscribe for more videos just like this one. Follow Me: https://twitter.com/CatechismYT Feel Free to Donate: https://www.patreon.com/Catechism Sources: Background Music: https://www.youtube.com/watch?v=6Sq5Y2HzF1c&t=41s Images: http://inanimate-objects.wikia.com/wiki/File:Solar_System.png http://www.wikiwand.com/ru/%D0%A1%D1%82%D0%BE%D1%8F_%D0%BD%D0%B0_%D0%9C%D0%BB%D0%B5%D1%87%D0%BD%D0%BE%D0%BC_%D0%9F%D1%83%D1%82%D0%B8 ESA/Hubble - https://en.wikipedia.org/wiki/File:Starsinthesky.jpg - Modified https://commons.wikimedia.org/wiki/File:Hubble_image_of_MACS_J0717_with_mass_overlay.jpg - Modified http://www.freepngimg.com/miscellaneous/galaxy https://commons.wikimedia.org/wiki/File:Logarhitmic_radial_photo_of_the_universe_by_pablo_budassi_9MFK.jpg - Modified

Dr. Steffen Info: https://www.unlv.edu/people/jason-steffen Twitch: twitch.tv/horizonSci Expansion image: https://upload.wikimedia.org/wikipedia/commons/thumb/6/6f/CMB_Timeline300_no_WMAP.jpg/450px-CMB_Timeline300_no_WMAP.jpg New map of Universe's dark matter: http://www.bbc.com/news/health-40817897 Alternatives to the Big Bang Theory Explained (Infographic): https://www.space.com/24781-big-bang-theory-alternatives-infographic.html -- Watch live at https://www.twitch.tv/skylias

SUBSCRIBE to Space with Sarah: http://tinyurl.com/k5wxw6x What’s the fate of our Universe? Will it expand forever, will it collapse on itself or will something completely different happen? And what will happen to all galaxies? In this episode of Space with Sarah, astrophysicist, Sarah, explains what current observations of our Universe tell us about the fate of our Universe. All Space with Sarah season 1 episodes now have Danish and English subtitles. Don’t forget to subscribe to the channel and post your comments and questions below. Thanks for watching! Creator: Sarah Pearson Producer: Brett Van Deusen Animator: Joshua Bogy Image credits: NASA Via Lactea II - Diemand et al. 2008, Nature Digital graphics by Morgan Mullen Episode music by Krychek: http://krychek.nyc Episode background: Via Lactea II simulation by Diemand, Kuhlen, Madau et al. 2008, Nature Intro graphics by Frederik Olufsen: http://thefrederik.com/portfolio/ Intro Music by Palm Tree Gang & Max Fail (courtesy of Riotville Records): https://soundcloud.com/riotville-records/palm-tree-gang-max-fail-chameleon-feat-anuka Sound design by Tim Korn Dungeon Beach: http://dungeonbeach.com/ Color correction: Jeff Sousa Partially supported by the National Science Foundation: NSF grant AST-1614743

Why does the universe seem to be moving in one particular direction? You can further support us on Patreon at https://www.patreon.com/pbsspacetime Get your own Space Time t­shirt at http://bit.ly/1QlzoBi Tweet at us! @pbsspacetime Facebook: facebook.com/pbsspacetime Email us! pbsspacetime [at] gmail [dot] com Comment on Reddit: http://www.reddit.com/r/pbsspacetime Help translate our videos! https://www.youtube.com/timedtext_cs_... Previous Episode: The Secrets of Feynman Diagrams https://www.youtube.com/watch?v=fG52mXN-uWI Space is not static. Everything moves. Planets orbit stars, stars orbit within galaxies, galaxies whirl within the gravitational fields of giant clusters. And of course, the universe is expanding; distant galaxies are thrust apart from each other as the space between them grows. But there’s no preferred direction to any of this motion. Motion due to the expansion of the universe – what we call the Hubble flow – is equal in all directions. The random motion of galaxies – what we call their peculiar motion – should also have no preferred direction. On the largest scales of the universe, there should be no preference for up or down or left or right. At least that’s what we thought. Observations of the cosmic microwave background suggest that the galaxy clusters across the cosmos may be moving, ever so slightly, towards the same point beyond the cosmic horizon. We call this dark flow. Written and Hosted by Matt O’Dowd Produced by Rusty Ward Graphics by Kurt Ross Assistant Editing and Sound Design by Mike Petrow Made by Kornhaber Brown (www.kornhaberbrown.com) Comments answer by Matt: VacuumDiagrams https://www.youtube.com/watch?v=fG52mXN-uWI&lc=z12mir3gvw20gxvnq23md5ipdy2xvb33y Samuel Benda https://www.youtube.com/watch?v=fG52mXN-uWI&lc=z12vgjnosweevr1kw22oct0jfwugib4pu04 JoJoModding https://www.youtube.com/watch?v=fG52mXN-uWI&lc=z134h3i4zuqowhcow04cjfeh3pnmwpmirbk Squid Master https://www.youtube.com/watch?v=fG52mXN-uWI&lc=z123ynkp0m3uhhr4h04cjvxwpkvyvvmo2ek Special thanks to our Patreon Big Bang, Quasar and Hypernova Supporters: Big Bang CoolAsCats David Nicklas Eugene Lawson Quasar Tambe Barsbay Max Levine Mayank M. Mehrota Mars Yentur Josh Mark Rosenthal Dean Fuqua Hypernova Chuck Zegar Jordan Young Ratfeast John Hofmann Joseph Salomone Martha Hunt Craig Peterson Science Via Markets Barry Hatfield Thanks to our Patreon Gamma Ray Burst Supporters: Peter Durocher Michael Kers Chris Hicks Mark Vasile Patrick Murray Sultan Alkhulaifi Alex Seto Conor Dillon Jared Moore Michal-Peanut Karmi Bernardo Higuera Erik Stein Daniel Lyons Kevin Warne JJ Bagnell J Rejc Amy Jie Avi Goldfinger John Pettit Shannan Catalano Florian Stinglmayr Yubo Du Benoit Pagé-Guitard Nathan Leniz Jessica Fraley Loro Lukic Brandon Labonte David Crane Greg Weiss

A collaboration with Jorge Cham and Daniel Whiteson, check out "We Have No Idea" at http://www.wehavenoidea.com Jorge's PhDComics: http://www.phdcomics.com Numberphile video about sports in hyperbolic space: https://www.youtube.com/watch?v=u6Got0X41pY Support MinutePhysics on Patreon! http://www.patreon.com/minutephysics Link to Patreon Supporters: http://www.minutephysics.com/supporters/ MinutePhysics is on twitter - @minutephysics And facebook - http://facebook.com/minutephysics And Google+ (does anyone use this any more?) - http://bit.ly/qzEwc6 This video is about the local and global geometry and curvature of space and spacetime, aka, is space flat? Negatively curved? Positively curved? etc. Minute Physics provides an energetic and entertaining view of old and new problems in physics -- all in a minute! Created by Henry Reich

Fasten your interstellar seatbelt and flip your brain into overdrive. Neil deGrasse Tyson and comic co-host Godfrey are here to answer fan-submitted Cosmic Queries on the fabric of spacetime. Explore the edge of the known universe and whether there might be more unknown universe waiting beyond the horizon. You’ll hear about the fascinating theory describing our universe as a 3-D holographic projection of another higher-dimensioned reality. You’ll hear why dark matter could be “gravitational bleeding” from another dimension and how it’s possible that the study of dark matter and dark energy will unlock the secrets to traveling backwards in time. Investigate the connections between dark matter, Newtonian physics, and Occam’s razor. Neil also explains why the curvature of space is hard for us to see given that we are embedded in space itself. Find out about the Fermi paradox and the idea that extraterrestrial life might have already visited Earth and deemed life unintelligent. Discover more about Sir Isaac Newton: the problems Neil would ask him to solve today, how he invented calculus on a dare, and why Godfrey thinks he might be annoying to talk to in the modern era. All this, plus, a fan asks Neil, “How many physicists does it take to change a light bulb?” and his response is something you will not want to miss. For more exclusive content and commercial-free full episodes, subscribe to StarTalkAllAccess.com If you love StarTalk Radio, don't miss out on any StarTalk news. Sign up for our free newsletter: http://www.startalkradio.net/newsletter/youtube/ Catch up with StarTalk Radio around the web: iTunes - http://bit.ly/SOHDg6 SoundCloud - https://soundcloud.com/startalk Stitcher - http://www.stitcher.com/podcast/startalk TuneIn - http://tunein.com/radio/StarTalk-Radio-p334521/ Google Play Music - https://play.google.com/music/m/I6lczawbvvafjdburzbcc23aacu?t=StarTalk_Radio Twitter - https://twitter.com/StarTalkRadio Facebook - http://www.facebook.com/StarTalkRadio Google+ - https://plus.google.com/+startalkradio Snapchat - https://www.snapchat.com/add/startalk-radio Pinterest - http://pinterest.com/startalk/ Tumblr - http://startalkradio.tumblr.com/ Instagram - http://instagram.com/startalkradio The List App - https://li.st/startalkradio

Scientists announced July 6 at the European Physical Society Conference on High Energy Physics that a rare new kind of particle was unambiguously observed for the first time

How to predict the path of a quantum particle. Part 3 in our Quantum Field Theory Series. You can further support us on Patreon at https://www.patreon.com/pbsspacetime Get your own Space Time t­shirt at http://bit.ly/1QlzoBi Tweet at us! @pbsspacetime Facebook: facebook.com/pbsspacetime Email us! pbsspacetime [at] gmail [dot] com Comment on Reddit: http://www.reddit.com/r/pbsspacetime Help translate our videos! https://www.youtube.com/timedtext_cs_panel?tab=2&c=UC7_gcs09iThXybpVgjHZ_7g Previous Episode: The First Quantum Field Theory https://www.youtube.com/watch?v=ATcrrzJFtBY There is a fundamental limit to the knowability of the universe. The Heisenberg uncertainty principle tells us that the more precisely we try to define one property, the less definable is its counterpart. Knowing a particle’s location perfectly means its velocity is unknowable. But unmeasured properties are not just uncertain; they are undefined. Quantum mechanics seems to imply that ALL possible properties, paths, or events that could reasonably occur between measurements DO occur. Whether or not this is true, a mathematical description of this crazy idea led to the most powerful expression of quantum mechanics ever devised: Richard Feynman’s path integral formulation. Written and Hosted by Matt O’Dowd Produced by Rusty Ward Graphics by Kurt Ross Made by Kornhaber Brown (www.kornhaberbrown.com) Comments answer by Matt: Satya Prakash https://www.youtube.com/watch?v=ATcrrzJFtBY&lc=z12bv5hpgoyadn20522zfvo5eur2vftyy04 Jakub Mintal https://www.youtube.com/watch?v=ATcrrzJFtBY&lc=z13pvhcyeyj1uzqxv04cejkbtsm1shfgkug0k The EEZZ https://www.youtube.com/watch?v=ATcrrzJFtBY&lc=z12bdbax0ymdgvqec23ps1pyovjuh3zv2 Lazarus The adventurer https://www.youtube.com/watch?v=ATcrrzJFtBY&lc=z13pgd0z4uudt55fa22nthxykxilfbrcy ForTiorI https://www.youtube.com/watch?v=ATcrrzJFtBY&lc=z123hrop2tmlhnx1l23fdznq4q24ft4iw04 Special thanks to our Patreon Big Bang, Quasar and Hypernova Supporters: Big Bang CoolAsCats Shane Robinson David Nicklas Eugene Lawson Joshua Davis Quasar Tambe Barsbay Max Levine Mayank M. Mehrota Mars Yentur Hypernova Chuck Zegar Jordan Young Ratfeast John Hofmann Joseph Salomone Martha Hunt Craig Peterson Prof. Dr. Kenneth Michael Beck Science Via Markets Thanks to our Patreon Gamma Ray Burst Supporters: Justin Lloyd Sultan Alkhulaifi Alex Seto Conor Dillon Jared Moore Michal-Peanut Karmi Bernardo Higuera Erik Stein Daniel Lyons Kevin Warne JJ Bagnell J Rejc Amy Jie Avi Goldfinger John Pettit Shannan Catalano Florian Stinglmayr Yubo Du Benoit Pagé-Guitard Nathan Leniz Jessica Fraley Loro Lukic Brandon Labonte David Crane Greg Weiss

SUBSCRIBE to Space with Sarah: http://tinyurl.com/k5wxw6x Black holes are mysterious objects. They are so massive that even light cannot escape them! This makes them hard for astronomers to actually detect as we cannot *see them*. In this video astrophysicist, Sarah, explains how we can infer that a very massive black hole must exist at the center of our own galaxy, the Milky Way, based on the motions of stars in the center of our Galaxy. As it turns out, all massive galaxies seem to have super massive black holes at their centers. Please ask any questions you might have in the comment section. Creator: Sarah Pearson Producer: Brett Van Deusen Animator: Joshua Bogy Image credits: NASA Hubble NASA Spitzer ESO ESO/GAIA Steve Bowers Via Lactea II - Diemand et al. 2008, Nature Digital graphics by Morgan Mullen Episode music by Krychek: http://krychek.nyc Episode background: Via Lactea II simulation by Diemand, Kuhlen, Madau et al. 2008, Nature Intro graphics by Frederik Olufsen: http://thefrederik.com/portfolio/ Intro Music by Palm Tree Gang & Max Fail (courtesy of Riotville Records): https://soundcloud.com/riotville-records/palm-tree-gang-max-fail-chameleon-feat-anuka Sound design by Tim Korn Color correction: Jeff Sousa Partially supported by the National Science Foundation: NSF grant AST-1614743

Revisit a classic: Watch Paolo de Bernardis's talk (Università degli Studi di Roma "La Sapienza") from November 19, 2009 symposium at the Keck Institute for Space Studies - Challenging the Paradigm: The Legacy of Galileo.

SUBSCRIBE to Space with Sarah: http://tinyurl.com/k5wxw6x Based on observations, astronomers have determined that there is five times more dark matter than normal matter in the Universe. But have you ever wondered how astronomers actually measured this? In this video astrophysicist, Sarah, explains why we think dark matter exists and how we measure the amount of dark matter in space. Hopefully, we'll also figure out what dark matter actually is in the near future! If you are curious about dark matter and want to learn more, check out the latest Space with Sarah collaboration with Fraser Cain from Universe today, where we discuss dark matter galaxies: https://www.youtube.com/watch?v=knw10ooUCK4&t=149s Creator: Sarah Pearson Producer: Brett Van Deusen Animator: Joshua Bogy Image credits: NASA Hubble Via Lactea II - Diemand et al. 2008, Nature Digital graphics by Morgan Mullen Episode music by Krychek: http://krychek.nyc Episode background: Via Lactea II simulation by Diemand, Kuhlen, Madau et al. 2008, Nature Intro graphics by Frederik Olufsen: http://thefrederik.com/portfolio/ Intro Music by Palm Tree Gang & Max Fail (courtesy of Riotville Records): https://soundcloud.com/riotville-records/palm-tree-gang-max-fail-chameleon-feat-anuka Sound design by Tim Korn Color correction: Jeff Sousa Partially supported by the National Science Foundation: NSF grant AST-1614743

Cosmologists tell us that the Universe is flat. It sure feels like 3-dimensions. What does this even mean, and how do we know it’s true? Support us at: http://www.patreon.com/universetoday More stories at: http://www.universetoday.com/ Follow us on Twitter: @universetoday Like us on Facebook: https://www.facebook.com/universetoday Google+ - https://plus.google.com/+universetoday/ Instagram - http://instagram.com/universetoday Team: Fraser Cain - @fcain / [email protected] Karla Thompson - @karlaii Chad Weber - [email protected] Whenever we talk about the expanding Universe, everyone wants to know how this is going to end. Sure, they say, the fact that most of the galaxies we can see are speeding away from us in all directions is really interesting. Sure, they say, the Big Bang makes sense, in that everything was closer together billions of years ago. But how does it end? Does this go on forever? Do galaxies eventually slow down, come to a stop, and then hurtle back together in a Big Crunch? Will we get a non-stop cycle of Big Bangs, forever and ever? We’ve done a bunch of episodes on many different aspects of this question, and the current conclusion astronomers have reached is that because the Universe is flat, it’s never going to collapse in on itself and start another Big Bang. But wait, what does it mean to say that the Universe is “flat”? Why is that important, and how do we even know? Before we can get started talking about the flatness of the Universe, we need to talk about flatness in general. What does it mean to say that something is flat? If you’re in a square room and walk around the corners, you’ll return to your starting point having made 4 90-degree turns. You can say that your room is flat. This is Euclidian geometry. But if you make the same journey on the surface of the Earth. Start at the equator, make a 90-degree turn, walk up to the North Pole, make another 90-degree turn, return to the equator, another 90-degree turn and return to your starting point. In one situation, you made 4 turns to return to your starting point, in another situation it only took 3. That’s because the topology of the surface you were walking on decided what happens when you take a 90-degree turn. You can imagine an even more extreme example, where you’re walking around inside a crater, and it takes more than 4 turns to return to your starting point. Another analogy, of course, is the idea of parallel lines. If you fire off two parallel lines at the North pole, they move away from each other, following the topology of the Earth and then come back together. Got that? Great. Now, what about the Universe itself? You can imagine that same analogy. Imaging flying out into space on a rocket for billions of light-years, performing 90-degree maneuvers and returning to your starting point. You can’t do it in 3, or 5, you need 4, which means that the topology of the Universe is flat. Which is totally intuitive, right? I mean, that would be your assumption. But astronomers were skeptical and needed to know for certain, and so, they set out to test this assumption. In order to prove the flatness of the Universe, you would need to travel a long way. And astronomers use the largest possible observation they can make. The Cosmic Microwave Background Radiation, the afterglow of the Big Bang, visible in all directions as a red-shifted, fading moment when the Universe became transparent about 380,000 years after the Big Bang. When this radiation was released, the entire Universe was approximately 2,700 C. This was the moment when it was cool enough for photons were finally free to roam across the Universe. The expansion of the Universe stretched these photons out over their 13.8 billion year journey, shifting them down into the microwave spectrum, just 2.7 degrees above absolute zero. With the most sensitive space-based telescopes they have available, astronomers are able to detect tiny variations in the temperature of this background radiation. And here’s the part that blows my mind every time I think about it. These tiny temperature variations correspond to the largest scale structures of the observable Universe. A region that was a fraction of a degree warmer become a vast galaxy cluster, hundreds of millions of light-years across. The Cosmic Microwave Background Radiation just gives and gives, and when it comes to figuring out the topology of the Universe, it has the answer we need. If the Universe was curved in any way, these temperature variations would appear distorted compared to the actual size that we see these structures today. But they’re not. To best of its ability, ESA’s Planck space telescope, can’t detect any distortion at all. The Universe is flat.

The Big Bang was a tremendous theory, but it had a few problems. In 1980 Alan Guth developed the revolutionary theory of cosmic inflation, and astronomers have been looking for evidence to this day. Support us at: http://www.patreon.com/universetoday More stories at: http://www.universetoday.com/ Follow us on Twitter: @universetoday Like us on Facebook: https://www.facebook.com/universetoday Google+ - https://plus.google.com/+universetoday/ Instagram - http://instagram.com/universetoday Team: Fraser Cain - @fcain / [email protected] Karla Thompson - @karlaii Chad Weber - [email protected] The Big Bang. The discovery that the Universe has been expanding for billions of years is one of the biggest revelations in the history of science. In a single moment, the entire Universe popped into existence, and has been expanding ever since. We know this because of multiple lines of evidence: the cosmic microwave background radiation, the ratio of elements in the Universe, etc. But the most compelling one is just the simple fact that everything is expanding away from everything else. Which means, that if you run the clock backwards, the Universe was once an extremely hot dense region Let’s go backwards in time, billions of years. The closer you get to the Big Bang, the closer everything was, and the hotter it was. When you reach about 380,000 years after the Big Bang, the entire Universe was so hot that all matter was ionized, with atomic nuclei and electrons buzzing around each other. Keep going backwards, and the entire Universe was the temperature and density of a star, which fused together the primordial helium and other elements that we see to this day. Continue to the beginning of time, and there was a point where everything was so hot that atoms themselves couldn’t hold together, breaking into their constituent protons and neutrons. Further back still and even atoms break apart into quarks. And before that, it’s just a big question mark. An infinitely dense Universe cosmologists called the singularity. When you look out into the Universe in all directions, you see the cosmic microwave background radiation. That’s that point when the Universe cooled down so that light could travel freely through space. And the temperature of this radiation is almost exactly the same in all directions that you look. There are tiny tiny variations, detectable only by the most sensitive instruments. When two things are the same temperature, like a spoon in your coffee, it means that those two things have had an opportunity to interact. The coffee transferred heat to the spoon, and now their temperatures have equalized. When we see this in opposite sides of the Universe, that means that at some point, in the ancient past, those two regions were touching. That spot where the light left 13.8 billion years ago on your left, was once directly touching that spot on your right that also emitted its light 13.8 billion years ago. This is a great theory, but there’s a problem. The Universe never had time for those opposite regions to touch. For the Universe to have the uniform temperature we see today, it would have needed to spend enough time mixing together. But it didn’t have enough time, in fact, the Universe didn’t have any time to exchange temperature. Imagine you dipped that spoon into the coffee and then pulled it out moments later before the heat could transfer, and yet the coffee and spoon are exactly the same temperature. What’s going on? To address this problem, the cosmologist Alan Guth proposed the idea of cosmic inflation in 1980. That moments after the Big Bang, the entire Universe expanded dramatically. And by “moments”, I mean that the inflationary period started when the Universe was only 10^-36 seconds old, and ended when the Universe was 10^-32 seconds old. And by “expanded dramatically”, I mean that it got 10^26 times larger. That’s a 1 followed by 26 zeroes. Before inflation, the observable Universe was smaller than an atom. After inflation, it was about 0.88 millimeters. Today, those regions have been stretched 93 billion light-years apart. This concept of inflation was further developed by cosmologists Andrei Linde, Paul Steinhardt, Andy Albrecht and others. Inflation resolved some of the shortcomings of the Big Bang Theory. The first is known as the flatness problem. The most sensitive satellites we have today measure the Universe as flat. Not like a piece-of-paper-flat, but flat in the sense that parallel lines will remain parallel forever as they travel through the Universe. Under the original Big Bang cosmology, you would expect the curvature of the Universe to grow with time. The second is the horizon problem. And this is the problem I mentioned above, that two regions of the Universe shouldn’t have been able to see each other and interact long enough to be the same temperature.

SUBSCRIBE to Space with Sarah: http://tinyurl.com/k5wxw6x Have you ever wondered how two galaxies can collide with each other when we know that the Universe is actually expanding? In this video astrophysicist, Sarah, explains how gravity still wins over the expansion of space on Galactic size scales. Creator: Sarah Pearson Producer: Brett Van Deusen Animator: Joshua Bogy Image credits: Illustration Credit: NASA/JPL/STScl, Z. Levay and R. van der Marel (STScI), T. Hallas, and A. Mellinger Via Lactea II - Diemand et al. 2008, Nature Digital graphics by Morgan Mullen Episode music by Krychek http://krychek.nyc Episode background: Via Lactea II simulation by Diemand, Kuhlen, Madau et al. 2008, Nature Intro graphics by Frederik Olufsen: http://thefrederik.com/portfolio/ Intro Music by Palm Tree Gang & Max Fail (courtesy of Riotville Records): https://soundcloud.com/riotville-records/palm-tree-gang-max-fail-chameleon-feat-anuka Sound design: Tim Korn Director of Photography: Joseph Ciccarella Color correction: Jeff Sousa Partially supported by the National Science Foundation: NSF grant AST-1614743

SUBSCRIBE to Space with Sarah: http://tinyurl.com/k5wxw6x Have you ever wondered how we can talk about the amount of galaxies that exist in the Universe, when we don’t know the size of the Universe? In this video astrophysicist, Sarah, explains how there is a size limit to the observable Universe. Creator: Sarah Pearson Producer: Brett Van Deusen Animator: Joshua Bogy Image credits: Via Lactea II - Diemand et al. 2008, Nature NASA/JPL/STScl “Edge of the Universe” - Mirela Momanu Millennium Simulation Project, Springel 2004 Digital graphics by Morgan Mullen Episode music by Krychek: http://krychek.nyc Episode background: Via Lactea II simulation by Diemand, Kuhlen, Madau et al. 2008, Nature Intro graphics by Frederik Olufsen: http://thefrederik.com/portfolio/ Intro Music by Palm Tree Gang & Max Fail (courtesy of Riotville Records): https://soundcloud.com/riotville-records/palm-tree-gang-max-fail-chameleon-feat-anuka Sound design by Tim Korn Color correction: Jeff Sousa Partially supported by the National Science Foundation: NSF grant AST-1614743

GALAXIES! Thanks for watching! xoxo

Produced in association with Caltech Academic Media Technologies and the Keck Institute for Space Studies. ©2017 California Institute of Technology

Stream Episodes on demand from www.bitesz.com or www.spacetimewithstuartgary.com (both mobile friendly) *The Black Hole Dark Matter hypothesis disproved A new study has provided strong evidence disproving the idea that unknown populations of ancient black holes could explain the effects currently attributed to dark matter. The findings imply that the detection of gravitational waves generated by colliding intermediate mass black holes can’t be used to imply the existence of huge populations of primordial black holes early in the history of the universe. *New evidence of a water rich history on Mars New research on Martian meteorites indicates that the red planet may have been a far wetter place than previously thought. The findings provide the first clear evidence that a mineral commonly found in Martian meteorites which was considered proof of an ancient dry environment on Mars -- may have originally been a hydrogen-containing mineral -- that could indicate a far more water-rich history for the Red Planet. *Stephen Hawking’s warning of alien invasion Theoretical physicist Stephen Hawking says while he believes intelligent alien life probably does exist elsewhere in the universe – making contact with them could be as disastrous for humans as Christopher Columbus’s arrival in the new world was for native Americans. He made the comments during the launch of his new documentary Stephen Hawking's Favourite Places. *New American Spy satellite launched A new top secret spy satellite has been successfully launched into orbit for America’s National Reconnaissance Office. The NROL-79 mission is believed to involve a pair of classified Naval Ocean Surveillance System INTRUDER Satellites. For Enhanced Show Notes, including photos to accompany this episode: http://www.bitesz.com/spacetime-show-notes Subscribe, rate and review SpaceTime at all good podcasting apps…including iTunes, audioBoom, Stitcher, Pocketcasts, Podbean, Radio Public, Tunein Radio, google play, etc. RSS feed: https://audioboom.com/channels/4642443.rss Help support SpaceTime : The SpaceTime with Stuart Gary merchandise shop. Get your T-Shirts, Coffee Cups, badges, tote bag + more and help support the show. Check out the range: http://www.cafepress.com/spacetime Thank you. Plus: Get a free audio book of your choice, plus 30 days free access from audible.com. Just visit www.audibletrial.com/spacetime or click on the banner link at www.spacetimewithstuartgary.com Email: [email protected] Join our mailing list at http://www.bitesz.com/join-our-mailing-list For more, follow SpaceTime on Facebook, twitter, Tumblr, YouTube, Google+ and Clammr: Facebook: @spacetimewithstuartgary twitter: @stuartgary Tumblr: http://spacetimewithstuartgary.tumblr.com/ Google+: https://plus.google.com/u/2/collection/cabtNB YouTube: https://www.youtube.com/playlist?list=PLhpBkuHSLfIRnliLB12HoC1QE0rwr8qRS Clammr: http://www.clammr.com/app/spacetime If you're enjoying SpaceTime, please help out by sharing and telling your friends. The best recommendation I can get is one from you. Thank you...

Most of the Universe is dark. The protons, neutrons and electrons that make up the stars, planets and us represent only a small fraction of the mass and energy of the Universe. The rest is dark and mysterious.

Looking for a cool domain? Try a .SPACE Domain Name for only $2.99 using this link: https://goo.gl/S9jsH2 Consider supporting Space Fan News: https://patreon.com/DeepAstronomy to ensure you get current space & astronomy news each week! Space Fan News Theme by Stephen Dubois available for download here: http://ancienteyesmusic.com Links for this week: Early Universe Expansion: http://www.spacetelescope.org/news/heic1702/ H0LiCOW Video: http://www.mpa-garching.mpg.de/404715/h0licow New Test for Life: http://www.jpl.nasa.gov/news/news.php?release=2017-017 Gaia Looks for Asteroids: http://sci.esa.int/gaia/58706-gaia-turns-its-eyes-to-asteroid-hunting/ Follow DeepAstronomy on Twitter: @DeepAstronomy Like DeepAstronomy on Facebook: https://www.facebook.com/DeepAstronomy/ Like Space Fan News on Facebook: https://www.facebook.com/SpaceFanNews/ Follow DeepAstronomy on Google+ http://google.com/+DeepAstronomy http://google.com/+TonyDarnell We also have a great Google+ Community, come share your thoughts and join the discussion! https://plus.google.com/communities/109849939648748938781t

v=Hd Welcome to the Hubble Constant and Hubble's Law!!! The first time I learned about this theory my mind exploded. It's too good to not share!! Hubble's Law is based on the discover made by Astronomer Edwin Hubble, that a lot of what we see in the night sky is not all from our Milky Way galaxy, but instead a whole other galaxy!!! This discover lead to the discovery of many other galaxies and the acceleration of them, leading to the realization that our universe is expanding--and expanding at a very fast rate at that! INSANE... I know! There's so much cool stuff to learn out there, so keep exploring and thanks for watching! See ya next week! xoxo

There’s one interpretation of the meaning of quantum mechanics that manages to skip a lot of the unphysical weirdness of the mainstream interpretations: it's de Broglie-Bohm pilot wave theory. Help us continue making this show by contributing here: https://www.patreon.com/pbsspacetime Get your own Space Time t­shirt at http://bit.ly/1QlzoBi Tweet at us! @pbsspacetime Facebook: facebook.com/pbsspacetime Email us! pbsspacetime [at] gmail [dot] com Comment on Reddit: http://www.reddit.com/r/pbsspacetime Help tranlate our videos! https://www.youtube.com/timedtext_cs_panel?tab=2&c=UC7_gcs09iThXybpVgjHZ_7g There are some pretty out-there explanations for the processes at work behind the incredibly successful mathematics of quantum mechanics - things are both waves and particles at the same time, the act of observation defines reality, cats are alive and dead, or even: the universe is constantly splitting into infinite alternate realities. The weird results of quantum experiments seem to demand weird explanations of the nature of reality. In this episode, Matt discusses de Broglie-Bohm pilot wave theory, the one interpretation of quantum mechanics that remains comfortably, stodgily physical. Links to Sources The Quantum Experiment that Broke Reality https://www.youtube.com/watch?v=p-MNSLsjjdo&t=53s The Many Worlds of the Quantum Multiverse https://www.youtube.com/watch?v=dzKWfw68M5U&t=690s Is This What Quantum Mechanics Looks Like? https://www.youtube.com/watch?v=WIyTZDHuarQ A Suggested Interpretation of the Quantum Theory in Terms of "Hidden" Variables. I: David Bohm, 1952, Phys. Rev. 85, 166 http://journals.aps.org/pr/abstract/10.1103/PhysRev.85.166 Bohms original paper is behind the journal paywall (sorry!), however many other readings on Bohmian mechanics are available here: http://www.bohmian-mechanics.net/readings_books.html Previous Space Time Episode https://www.youtube.com/watch?v=u4RNGRyzt10 Written and hosted by Matt O’Dowd Produced by Rusty Ward Made by Kornhaber Brown (www.kornhaberbrown.com) Comments Answered by Matt Burak Bağdatlı https://www.youtube.com/watch?v=u4RNGRyzt10&lc=z13hvpcjrlndslnyb04cctjqrvb4hpkphe4 Sebastián López https://www.youtube.com/watch?v=u4RNGRyzt10&lc=z124yxrjyw3ywvicm23wspagcxracphvg The757packerfan https://www.youtube.com/watch?v=u4RNGRyzt10&lc=z13ujbnznvmfjnhag04cgtprtriafnj4t2k Special thanks to our Patreon Hypernova and Quasar Supporters: Joel Brinton Antonio Park Alastair Taft Clock Watcher Joe John Hofmann Thanks to our Patreon Gamma Ray Burst Supporters: Jade Bilkey Kevin Warne JJ Bagnell J Rejc Bernardo Higuera Michael Fischer Dylan Merida Colette Weeks Amy Jie Anthony Caridi Avi Goldfinger Corey Smeaton John Pettit Shannan Catalano Florian Stinglmayr Yubo Du Benoit Pagé-Guitard Ronny Polonia Nathan Leniz Jessica Fraley Kirk Mathews Loro Lukic Carl P. Corliss Brandon labonte David Crane Greg Weiss David Matteson Marc Lagarde Eric Jackson Will and Sonja Marple

Did you hear that the Universe has 10x the number of galaxies? How did astronomers discover this, and what does it mean for the number of stars? References: http://www.nasa.gov/feature/goddard/2016/hubble-reveals-observable-universe-contains-10-times-more-galaxies-than-previously-thought http://www.jwst.nasa.gov/ http://jwst.nasa.gov/comparison.html https://www.wolframalpha.com/input/?i=mass+of+the+universe http://math.ucr.edu/home/baez/physics/Relativity/GR/olbers.html http://www.astro.ucla.edu/~wright/density.html Support us at: http://www.patreon.com/universetoday More stories at: http://www.universetoday.com/ Follow us on Twitter: @universetoday Follow us on Tumblr: http://universetoday.tumblr.com/ Like us on Facebook: https://www.facebook.com/universetoday Google+ - https://plus.google.com/+universetoday/ Instagram - http://instagram.com/universetoday Team: Fraser Cain - @fcain / [email protected] Jason Harmer - @jasoncharmer Chad Weber - [email protected] Created by: Fraser Cain and Jason Harmer Edited by: Chad Weber The wonderful thing about science is that it’s constantly searching for new evidence, revising estimates, throwing out theories, and sometimes discovering aspects of the Universe that we never realized existed. The best science is skeptical of itself, always examining its own theories to find out where they could be wrong, and seriously considering new ideas to see if they better explain the observations and data. What this means is that whenever I state some conclusion that science has reached, you can’t come back a few years later and throw that answer in my face. Science changes, it’s not my fault. I get it, VY Canis Majoris isn’t the biggest star any more, it’s whatever the biggest star is right now. UY Scuti? That what it is today, but I’m sure it’ll be a totally different star when you watch this in a few years. What I’m saying is, the science changes, numbers update, and we don’t need to get concerned when it happens. Change is a good thing. And so, it’s with no big surprise that I need to update the estimate for the number of galaxies in the observable Universe. Until a couple of weeks ago, the established count for galaxies was about 200 billion galaxies. But a new paper published in the Astrophysics Journal revised the estimate for the number of galaxies, by a factor of 10, from 200 billion to 2 trillion. 200 billion, I could wrap my head around, I say billion all the time. But 2 trillion? That’s just an incomprehensible number. Does that throw all the previous estimates for the number of stars up as well? Actually, it doesn’t. The observable Universe measures 13.8 billion light-years in all directions. What this means is that at the very edge of what we can see, is the light left that region 13.8 billion years ago. Furthermore, the expansion of the Universe has carried to those regions 46 billion light-years away. Does that make sense? The light you’re seeing is 13.8 billion light-years old, but now it’s 46 billion light-years away. What this means is that the expansion of space has stretched out the light from all the photons trying to reach us. What might have been visible or ultraviolet radiation in the past, has shifted into infrared, and even microwaves at the very edge of the observable Universe. Since astronomers know the volume of the observable Universe, and they can calculate the density of the Universe, they know the mass of the entire Universe. 3.4 x 10^54 kilograms including regular matter and dark matter. They also know the ratio of regular matter to dark matter, so they can calculate the total amount of regular mass in the Universe. In the past, astronomers divided that total mass by the number of galaxies they could see in the original Hubble data and determined there were about 200 billion galaxies. Now, astronomers used a new technique to estimate the galaxies and it’s pretty cool. Astronomers used the Hubble Space Telescope to peer into a seemingly empty part of the sky and identified all the galaxies in it. This is the Hubble Ultra Deep Field, and it’s one of the most amazing pictures Hubble has ever captured. Astronomers painstakingly converted this image of galaxies into a 3-dimensional map of galaxy size and locations. Then, they used their knowledge of galaxy structure closer to home to provide a more accurate estimate of what the galaxies must look like, out there, at the very edge of our observational ability. For example, the Milky Way is surrounded by about 50 satellite dwarf galaxies, each of which has a fraction of the mass of the Milky Way. By recognizing which were the larger main galaxies, they could calculate the distribution of smaller, dimmer dwarf galaxies that weren’t visible in the Hubble images. In other words, if the distant Universe is similar to the nearby Universe, and this is one of the principles of modern astronomy, then the distant galaxies have the same structure as nearby galaxies.