DO NOT TIP. This is an unofficial YouTube mirror of PBS Space Time (https://youtu.be/OvgZqGxF3eo). If you want to tip PBS Space Time please visit https://www.patreon.com/pbsspacetime/. Convince PBS Space Time to join Odysee! ----------------------------- Viewers like you help make PBS (Thank you ?) . Support your local PBS Member Station here: https://to.pbs.org/DonateSPACE Can we ever achieve absolute cold? Try CuriosityStream today: http://curiositystream.com/spacetime 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: When Quasars Collide STJC | Space Time https://www.youtube.com/watch?v=gtZ7OVoI2nc Resources: Absolute Zero: https://en.wikipedia.org/wiki/Absolute_zero Zero-Point Energy: https://en.wikipedia.org/wiki/Zero-point_energy Bose-Einstein Condensate: https://en.wikipedia.org/wiki/Bose-Einstein_condensate Alfred Leitner's Superfluid Liquid Helium: http://alfredleitner.com/superfluid.html Links to Comments Response: Rcoates89 https://www.youtube.com/watch?v=gtZ7OVoI2nc&lc=z22lcfrgpz2sg5ixd04t1aokgcrarmubr2l25rvpe2erbk0h00410 Joseph Gamble https://www.youtube.com/watch?v=gtZ7OVoI2nc&lc=z23xwxyhhnaiupzpm04t1aokgrzsld44qfcv4gwseddzbk0h00410 Dillan Burris https://www.youtube.com/watch?v=gtZ7OVoI2nc&lc=z22vflpxcoaajd0f3acdp435lhovrxjuxvfyg4vdjsxw03c010c Rubbergnome https://www.youtube.com/watch?v=gtZ7OVoI2nc&lc=z22phdvhwsyehtjxe04t1aokg1ewo1qi3ouyue3ocjgnbk0h00410 Many experimental physicists have spent their careers trying to cool things to absolute zero. This state of absolute cold is the zero-point on the Kelvin temperature scale, corresponding to -273.15 Celsius. Using lasers and magnetic fields, we’ve now managed to cool certain substances to less than a billionth of a Kelvin. Doing so has revealed some bizarre quantum states of matter. But quantum mechanics may also prevent us from ever reaching absolute zero. Understanding the limit to cold will lead us to an understanding of the nature of the quantum vacuum itself. 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

DO NOT TIP. This is an unofficial YouTube mirror of PBS Space Time (https://youtu.be/C4CKtEQJGMY). If you want to tip PBS Space Time please visit https://www.patreon.com/pbsspacetime/. Convince PBS Space Time to join Odysee! ----------------------------- You can learn more about CuriosityStream at https://curiositystream.com/spacetime PBS Member Stations rely on viewers like you. To support your local station, go to: http://to.pbs.org/DonateSPACE Check out the new Space Time Merch Store! https://pbsspacetime.com/ Support Space Time on Patreon https://www.patreon.com/pbsspacetime Hook up an old antenna to your TV and scan between channels. The static buzz you hear is mostly due to the ambient radio produced by our noisy pre-galactic civilization. But around one percent of that buzz is something very different – it’s the cosmic microwave background radiation – the remnant of the heat-glow released when the hot, dense early universe became transparent for the first time. It sound likes random static, but that buzz contains an incredible wealth of hidden information. It holds the secrets of the universe’s fiery beginning, 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 Sound Waves from the Beginning of Time https://www.youtube.com/watch?v=PPpUxoeooZk Hosted by Matt O'Dowd Written by Matt O'Dowd Graphics by Luke Maroldi Directing by Andrew Kornhaber It’s not surprising that scientists have spent half a century and built multiple satellites to unlock the mysteries of the cosmic microwave background. We’ve delved into its nature before – from its formation 380,000 years after the Big Bang, to its 1964 discovery by Penzias and Wilson with the Holmdel Horn Antenna, to its increasingly accurate mapping across the sky with ever-better satellites. It all culminated in this – the Planck satellite’s map of the CMB. Special thanks to our Patreon Big Bang, Quasar and Hypernova Supporters: Big Bang: Anton Lifshits coolascats David Nicklas Fabrice Eap Juan Benet Justin Lloyd Tim Davis Quasar: James Flowers Mark Rosenthal Tambe Barsbay Vinnie Falco Hypernova: chuck zegar Danton Spivey Donal Botkin Edmund Fokschaner Jens Theisen John Hofmann Jordan Young Joseph Salomone kkm Mark Heising Matthew O'Connor Thanks to our Patreon Gamma Ray Burst Supporters: Alexey Eromenko Antonio Ruiz Bradley Jenkins Brandon Labonte Buruk Aregawi Carlo Mogavero Daniel Lyons David Behtala David Crane David Schmidt Dustan Jones Geoffrey Short Greg Weiss Jack Frosch James Hughes James Quintero Jinal Doshi JJ Bagnell John Webber Jon Folks Jonah Joseph Emison Josh Thomas Kenneth F Leonard Kevin Warne Kyle Hofer Malte Ubl Mark Vasile Nathan Hitchings Nicholas Rose Nick Virtue Ratfeast Richard Broman Scott Gossett Sigurd Ruud Frivik Tim Crookham Tim Stephani Tommy Mogensen سلطان الخليفي

DO NOT TIP. This is an unofficial YouTube mirror of PBS Space Time (https://youtu.be/iTTa9YcTe1k). If you want to tip PBS Space Time please visit https://www.patreon.com/pbsspacetime/. Convince PBS Space Time to join Odysee! ----------------------------- You can learn more about The Great Courses Plus here: http://ow.ly/3qDN30hIvdb Viewers like you help make PBS (Thank you ?) . Support your local PBS Member Station here: https://to.pbs.org/DonateSPACE Some see string theory as the one great hope for a theory of everything – that it will unite quantum mechanics and gravity and so unify all of physics into one glorious theory. You can further support us on Patreon at https://www.patreon.com/pbsspacetime Get your own Space Time t­-shirt 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 Make Sure To Check Out The Great Courses Plus "The Great Courses Plus is currently available to watch through a web browser to almost anyone in the world and optimized for the US, UK, and Australian markets. The Great Courses Plus is currently working to both optimize the product globally and accept credit card payments globally." Help translate our videos! https://www.youtube.com/timedtext_cs_... Previous Episode: Are Virtual Particles A New Layer of Reality? https://www.youtube.com/watch?v=ztFovwCaOik Hosted by Matt O'Dowd Written by Matt O'Dowd Graphics by Luke Maroldi Assistant Editing and Sound Design by Mike Petrow Made by Kornhaber Brown (www.kornhaberbrown.com) Why has string theory been the obsession of a generation of theoretical physicists? What exactly is so compelling about tiny, vibrating strings? In our last string theory episode I talked about what these things really are, and covered some history. In short: the strings of string theory are literal strands and loops that vibrate with standing waves. Simply by changing the vibrational mode you get different particles – analogous to how different vibrational modes on guitar strings gives different notes. And, by the way, strings exist in 6 compact spatial dimensions on top of the familiar 3. Special thanks to our Patreon Big Bang, Quasar and Hypernova Supporters: Big Bang David Nicklas CoolAsCats Anton Lifshits Fabrice Eap Justin Lloyd Juan Benet Quasar Tambe Barsbay Mark Rosenthal Dean Fuqua James Flowers Vinnie Falco Hypernova Chuck Zegar Jordan Young Joseph Salomone John Hofmann Martha Hunt Matthew O’Connor Ratfeast Brent Mullins Donal Botkin Edmund Fokschaner Max Levine Thanks to our Patreon Gamma Ray Burst Supporters: Alexander Rodriguez Alexey Eromenko Brandon Cook Brandon Labonte Daniel Lyons David Crane Fabian Olesen Fauzan Ardhana Greg Allen Greg Weiss Jack Frosch James Hughes JJ Bagnell Jon Folks Joseph Emison Josh Thomas Kevin Warne Malte Ubl Mark Vasile Nathan Leniz Nicholas Rose Nick Virtue Scott Gossett Shannan Catalano Shawn Azman Tommy Mogensen سلطان الخليفي

DO NOT TIP. This is an unofficial YouTube mirror of PBS Space Time (https://youtu.be/7UNLgPIiWAg). If you want to tip PBS Space Time please visit https://www.patreon.com/pbsspacetime/. Convince PBS Space Time to join Odysee! ----------------------------- Did all of dark energy just vanish? A team of scientists have just analyzed new data and claim that we need to completely rethink its existence. This episode is supported by The Great Courses Plus. Go to http://ow.ly/EMoC304OIsh to start your free one month trial. 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 Support us on Patreon! http://www.patreon.com/pbsspacetime Help translate our videos! http://www.youtube.com/timedtext_cs_panel?tab=2&c=UC7_gcs09iThXybpVgjHZ_7g Why are we talking about dark energy again? Because another team has just announced a new analysis of updated supernova data. They claim that the data are consistent with there being NO dark energy – no accelerating expansion. They suggest that the universe may just be expanding at a constant rate – never speeding up, but also not slowing down. In this episode, Matt discusses this controversial claim, and whether or not we should throw away nearly twenty years of work on dark energy. Links to Sources Marginal Evidence for Cosmic Acceleration from Type Ia Supernovae J. T. Nielsen, A. Guffanti & S. Sarkar (2016) http://www.nature.com/articles/srep35596 Statistical hypothesis testing https://en.wikipedia.org/wiki/Statistical_hypothesis_testing Wolfram error analysis tutorial https://reference.wolfram.com/applications/eda/ExperimentalErrorsAndErrorAnalysis.html Previous Space Time Episode https://www.youtube.com/watch?v=ZY47bVu-0Bs Written and hosted by Matt O’Dowd Produced by Rusty Ward Graphics by Grayson Blackmon Made by Kornhaber Brown (www.kornhaberbrown.com) Comments Answered by Matt ThunderboltTangerine https://www.youtube.com/watch?v=dzKWfw68M5U&lc=z13ogdwyupendxfdo23xtnm5iufdghl4x04 QED https://www.youtube.com/watch?v=jowVq81AgGw&lc=z132djnarwaywxucv231i5fr0sz1yb2ff Teboski78 https://www.youtube.com/watch?v=jowVq81AgGw&lc=z12rspaoesqycbwvo22jtte4qqepidd1z