Channel: PBS Space Time

Category: Education

Tags: pbsmatt o’dowdarrowmathsgeneral relativitycalculusspaceeinsteinian physicszeno's paradoxquantum mechanicsastrobiologyscience fictionpbs space timephysicsrare earthspecial relativityouter spaceblack holesquantum zeno effect explainedquantum zeno effectholographic principleastrophysicsdark energyspace physicsholographic universethe universespace timetimeeinsteinmathdark matter

Description: Thank you for The Great Courses Plus for Supporting PBS. To learn more and try The Great Courses Plus click, ow.ly/ORgD30rA2tQ. PBS Member Stations rely on viewers like you. To support your local station, go to: to.pbs.org/DonateSPACE Sign Up on Patreon to get access to the Space Time Discord! patreon.com/pbsspacetime “A moving arrow is at rest.” This is obviously a nonsensical contradiction. But Zeno, a Greek philosopher famous for his metaphysical trolling, devised a paradox whose conclusion is just this. Here’s how it goes: if you look at an arrow flying through the air at any instantaneous snapshot in time, the arrow doesn’t travel any distance. If time is composed of an infinite number of these snapshots, and the arrow doesn’t move in any of them, then the arrow is at rest during the entirety of its flight. The moving arrow is at rest. In fact, if we’re talking about a quantum arrow, there may be a way to freeze its motion simply by looking at it, through the aptly named quantum Zeno effect. The quantum Zeno effect predicts that certain quantum events - like the electrons moving between atomic energy levels, or the decay of atomic nuclei, can be frozen through the simple act of observation. I’m going to tell you about some very real experiments that claim to have demonstrated this phenomenon. But first, let’s see if the quantum Zeno effect can save us from being shot by a quantum arrow. Check out the Space Time Merch Store pbsspacetime.com Sign up for the mailing list to get episode notifications and hear special announcements! mailchi.mp/1a6eb8f2717d/spacetime Hosted by Matt O'Dowd Written by Katie McCormick & Matt O'Dowd Graphics by Leonardo Scholzer, Yago Ballarini, Pedro Osinski, Adriano Leal & Stephanie Faria GFX Visualizations: Katherine Kornei Directed by Andrew Kornhaber Assistant Producer: Setare Gholipour Executive Producers: Eric Brown & Andrew Kornhaber End Credits Music by J.R.S. Schattenberg: youtube.com/channel/UCRl6-nb4iOnsij-vnpAjp0Q Special Thanks to Our Supporters on Patreon! Big Bang Supporters Brian Scott Rick DeWitt Sandy Wu Matthew Miller Brodie Rao Scott Gray Ahmad Jodeh Radu Negulescu Alexander Tamas Morgan Hough Juan Benet Vinnie Falco Fabrice Eap Mark Rosenthal David Nicklas Quasar Supporters Hank S Christina Oegren Mark Heising Hypernova Supporters William Bryan Rich Hammons Scott Gorlick Nick Berard Paul Stehr-Green Leo Emerson muOn Marketing Russell Pope Ben Delo L. Wayne Ausbrooks Nicholas Newlin Adrian Posor Mark Matthew Bosko Антон Кочков John R. Slavik Mathew Danton Spivey Donal Botkin John Pollock Edmund Fokschaner Joseph Salomone Matthew O'Connor chuck zegar Jordan Young m0nk John Hofmann Timothy McCulloch Gamma Ray Burst Supporters Alexey Kamenskiy Andrew Macleod Diana S Douglas Drane Ben Campbell Lawrence Tholl, DVM Faraz Khan Almog Cohen Alex Edwards Nick Ádám Kettinger Sylvain Leduc Anthony Kahng MD3 Endre Pech Daniel Jennings Cameron Sampson Pratik Mukherjee Geoffrey Clarion Nate Darren Duncan Lily kawaii Russ Creech Jeremy Reed Derek Davis Eric Webster Steven Sartore David Johnston J. King Michael Barton Christopher Barron James Ramsey Drew Hart Justin Jermyn Mr T Andrew Mann Jeremiah Johnson fieldsa eleanory Peter Mertz Kevin O'Connell Richard Deighton Isaac Suttell Devon Rosenthal Oliver Flanagan Dawn M Fink Bleys Goodson Darryl J Lyle Robert Walter Bruce B Ismael Montecel Simon Oliphant Mirik Gogri Mark Daniel Cohen Brandon Lattin Nickolas Andrew Freeman Shane Calimlim Tybie Fitzhugh Robert Ilardi Astaurus Eric Kiebler Craig Stonaha Martin Skans Michael Conroy Graydon Goss Frederic Simon Tonyface John Robinson A G Kevin Lee Adrian Hatch Yurii Konovaliuk John Funai Cass Costello Geoffrey Short Bradley Jenkins Kyle Hofer Tim Stephani Luaan AlecZero Vlad Shipulin Cody Malte Ubl King Zeckendorff Nick Virtue Scott Gossett Martin J Lollar Dan Warren Patrick Sutton John Griffith Daniel Lyons DFaulk GrowingViolet Kevin Warne Andreas Nautsch Brandon labonte