PBS Space Time

Feynman's Infinite Quantum Paths

PBS Space Time

Show Notes

Viewers like you help make PBS (Thank you 😃) . Support your local PBS Member Station here: https://to.pbs.org/DonateSPACEUploaded 07-07-17How 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/pbsspacetimeGet your own Space Time t­shirt at http://bit.ly/1QlzoBiTweet at us! @pbsspacetimeFacebook: facebook.com/pbsspacetimeEmail us! pbsspacetime [at] gmail [dot] comComment on Reddit: http://www.reddit.com/r/pbsspacetimeHelp translate our videos! https://www.youtube.com/timedtext_cs_panel?tab=2&c=UC7_gcs09iThXybpVgjHZ_7gPrevious Episode:The First Quantum Field Theoryhttps://www.youtube.com/watch?v=ATcrrzJFtBYThere 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 WardGraphics by Kurt RossMade by Kornhaber Brown (www.kornhaberbrown.com)Comments answer by Matt:Satya Prakashhttps://www.youtube.com/watch?v=ATcrrzJFtBY&lc=z12bv5hpgoyadn20522zfvo5eur2vftyy04Jakub Mintalhttps://www.youtube.com/watch?v=ATcrrzJFtBY&lc=z13pvhcyeyj1uzqxv04cejkbtsm1shfgkug0kThe EEZZhttps://www.youtube.com/watch?v=ATcrrzJFtBY&lc=z12bdbax0ymdgvqec23ps1pyovjuh3zv2Lazarus The adventurerhttps://www.youtube.com/watch?v=ATcrrzJFtBY&lc=z13pgd0z4uudt55fa22nthxykxilfbrcyForTiorIhttps://www.youtube.com/watch?v=ATcrrzJFtBY&lc=z123hrop2tmlhnx1l23fdznq4q24ft4iw04Special thanks to our Patreon Big Bang, Quasar and Hypernova Supporters: Big BangCoolAsCatsShane RobinsonDavid NicklasEugene LawsonJoshua DavisQuasarTambe BarsbayMax LevineMayank M. MehrotaMars YenturHypernovaChuck ZegarJordan YoungRatfeastJohn HofmannJoseph Salomone Martha HuntCraig PetersonProf. Dr. Kenneth Michael BeckScience Via MarketsThanks to our Patreon Gamma Ray Burst Supporters: Justin LloydSultan AlkhulaifiAlex SetoConor DillonJared MooreMichal-Peanut KarmiBernardo HigueraErik SteinDaniel LyonsKevin WarneJJ BagnellJ RejcAmy JieAvi GoldfingerJohn PettitShannan CatalanoFlorian StinglmayrYubo DuBenoit Pagé-GuitardNathan LenizJessica FraleyLoro LukicBrandon LabonteDavid CraneGreg Weiss Learn more about your ad choices. Visit megaphone.fm/adchoices Learn more about your ad choices. Visit megaphone.fm/adchoices

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Viewers like you help make PBS (Thank you 😃) . Support your local PBS Member Station here: https://to.pbs.org/DonateSPACEUploaded 20-12-17Find out about the last time and the next time the Earth will be hit by a Gamma-ray Burst. You can learn more about your personal DNA story by going to https://23andme.com/spacetimeYou can further support us on Patreon at https://www.patreon.com/pbsspacetimeGet your own Space Time t­shirt at http://bit.ly/1QlzoBiTweet at us! @pbsspacetimeFacebook: facebook.com/pbsspacetimeEmail us! pbsspacetime [at] gmail [dot] comComment on Reddit: http://www.reddit.com/r/pbsspacetimeHelp translate our videos!https://www.youtube.com/timedtext_cs_panel?tab=2&c=UC7_gcs09iThXybpVgjHZ_7gPrevious Episode:The Origin of Our First Interstellar Visitorhttps://www.youtube.com/watch?v=nYGs92-qnFYGamma-ray bursts are much less common than regular supernovae, and in fact regular supernovae can do just as much damage as a GRB. However, for a supernova to produce the same effects it needs to be much closer – within 20 to 30 light years. There are definitely no stars in that range that could explode any time soon. However the Sun isn’t stationary. It orbits the Milky Way, and its galactic neighbors come and go. Maybe in a few 250-million-year orbits we stellar timebomb will wander into our vicinity. However it’s really the GRBs that are most likely to hit us first, and hit us more often. We should certainly expect one in the next half-to-one-billion years, even if it’s not WR104.Hosted by Matt O'DowdWritten by Matt O'DowdProduced by Rusty WardGraphics by Kurt RossAssistant Editing and Sound Design by Mike Petrow and Meah Denee BarringtonMade by Kornhaber Brown (www.kornhaberbrown.com)Special thanks to our Patreon Big Bang, Quasar and Hypernova Supporters: Big BangCoolAsCatsDavid NicklasWilliam James SidisQuasarTambe BarsbayMayank M. MehrotaMars YenturMark RosenthalDean FuquaY2Justin LloydTambe BarsbayHypernovaEdmund FokschanerMax LevineMatthew O’ConnorEugene LawsonMartha HuntJoseph SalomoneChuck ZegarJordan YoungRatfeastJohn HofmannThanks to our Patreon Gamma Ray Burst Supporters: Mechanically CrypticDenys IvanovNick VirtueAlexey EromenkoNicholas RoseScott GossettMark DykstraChris HicksMark VasilePatrick MurraySultan AlkhulaifiAlex SetoMichal-Peanut KarmiErik SteinDaniel LyonsKevin WarneJJ BagnellJ RejcAmy JieAvi GoldfingerJohn PettitShannan CatalanoFlorian StiglmayrBenoit Pagé-GuitardNathan LenizJessica FraleyLoro LukicBrandon LabonteDavid CraneGreg Weiss Learn more about your ad choices. Visit megaphone.fm/adchoices Learn more about your ad choices. Visit megaphone.fm/adchoices

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Thank you for The Great Courses Plus for supporting PBS. To learn more click http://ow.ly/oSus30qpmwXUploaded 16-03-20PBS Member Stations rely on viewers like you. To support your local station, go to: http://to.pbs.org/DonateSPACESign Up on Patreon to get access to the Space Time Discord! https://www.patreon.com/pbsspacetimeSign up for the mailing list to get episode notifications and hear special announcements!https://tinyurl.com/yx9cusk5Check out the Space Time Merch Storehttps://pbsspacetime.com/This episode of space time is brought to you by the information flowing through an impossibly complex network of quantum entanglement, that just happens to mutually agree that you and I exist inside it. Oh, and Schrodinger’s cat is in here too.Hosted by Matt O'DowdWritten by Matt O'DowdGraphics by Leonardo Scholzer, Yago Ballarini, and Pedro OsinskiDirected by: Andrew KornhaberExecutive Producers: Eric Brown and Andrew KornhaberEnd Credits Music by J.R.S. Schattenberg: https://www.youtube.com/channel/UCRl6-nb4iOnsij-vnpAjp0QIn quantum world things are routinely in multiple states at once - what we call a “superposition” of states. But in the classical world of large scales, things are either this or that. The famous thought experiment is Schrodinger’s cat - in which a cat is in an opaque box with a vial of deadly poison that’s released on the radioactive decay of an atom. Quantum mechanics tells us that the atom’s wavefunction can be in a superposition of states - simultaneously decayed or not decayed. So is the cat’s wavefunction also in a superposition of both dead and alive.Special Thanks to Our Patreon SponsorsBig Bang SponsorsAlexander TamasDavid NicklasFabrice EapJuan BenetMorgan HoughRadu NegulescuQuasar SponsorsChristina OegrenMark HeisingVinnie FalcoHyper Nova SponsorsChuck ZegarDanton SpiveyDonal BotkinEdmund FokschanerHank SJohn HofmannJohn PollockJohn R. SlavikJordan YoungJoseph SalomoneJulian TyackeJustin AshMathewMatthew O'ConnorMatthew RyanSyed AnsarTimothy McCullochGamma Ray Burst SponsorsA GAdrian HatchAdrien MolyneuxAlecZeroAndreas NautschAngela PriggeArefa AhmadBradley JenkinsBrandon labonteBrandon LattinBrian BlanchardCraig StonahaDan WarrenDaniel LyonsDavid BethalaDFaulkDouglas CantrellEric KieblerFrederic SimonGeoffrey ShortGraydon GossGreg SmithJohn FunaiJohn RobinsonJonathan NesfederJosh ThomasKevin LeeKevin WarneKyle HoferMalte UblMichael ConroyNick VirtueNick WrightNickolas Andrew FreemanPatrick SuttonPaul RoseProtius ProtiusRandall SylviaRobert IlardiScott GossettSean WarniahaShane CalimlimSipke SchoorstraSteve BradshawTatiana VorovchenkoTim StephaniTonyfaceTybie FitzhughYannick WeynsYurii Konovaliuk Learn more about your ad choices. Visit megaphone.fm/adchoices Learn more about your ad choices. Visit megaphone.fm/adchoices

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