Are Axions Dark Matter?

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What does the strong nuclear force, the fundamental symmetries of nature, and a laundry detergent have in common? They’re all important parts of the tale of the axion - a tale whose end may take us beyond the standard model and solve one of the most vexing mysteries in astrophysics.
Hosted by Matt O'Dowd
Written by Matt O'Dowd & Graeme Gossel
Graphics by Leonardo Scholzer & Adriano Leal
Post Production: Yago Ballarini, Max Willians, Pedro Osinski
Directed by: Andrew Kornhaber
Executive Producers: Eric Brown & Andrew Kornhaber
The story of the axion is a classic physics tale: intrepid scientists delve deep into trackless mathematics in search of answers to a mystery. And there, against all expectations, they find the hint of a completely new and unexpected denizen of the natural world. In this case the mystery was a subtle inconsistency in the behavior of the fundamental forces. And the unexpected discovery? A brand new particle - the axion - which, while not proven to exist, may explain a much more famous conundrum. The axion may explain dark matter.
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  1. Frank Jaeger

    Frank Jaeger3 цагийн өмнө

    I believe that in Latin the letter "c" is always pronounced as the letter "k". So the second way you pronounced it would be the most correct.

  2. Max Jones

    Max Jones6 цагийн өмнө

    I love your content Cosmic Jesus.

  3. shipmaster3

    shipmaster37 цагийн өмнө

    Do you think that there is some relationship between the photon energy and the strength of a magnetic field needed to convert it? or is it just a sufficiently strong magnetic field is needed to any photon into an axion regardless of energy ?

  4. Cierra Mist

    Cierra Mist9 цагийн өмнө

    If the spin of a black hole can rip away its event horizon revealing a "naked singularity", would all the mass that's in the singularity come exploding out? Maybe the big bang was an event like this?

  5. Manus Artifex

    Manus Artifex10 цагийн өмнө

    Anxious dark matter

  6. Sister of Gaia

    Sister of Gaia10 цагийн өмнө

    If you take the remove the first 5 00000 from the quantum vacuum number measurment of the Universe. It would explode 💥 and we would not be here 📌

  7. weylguy

    weylguy15 цагийн өмнө

    Wow - explaining an undetectable form of matter with another undetectable form of matter. Turtles all the way down? But I love this PBS program!

  8. mettaur01

    mettaur0116 цагийн өмнө

    Is this where all the perverted Globe Earthers hang out?

  9. Scoring digits, son.

    Scoring digits, son.16 цагийн өмнө

    Maj kohoni? Nahe!

  10. PouncingAnt

    PouncingAnt17 цагийн өмнө

    Excellent. Sounds like Axions are an elegant solution to at least two big physics problems. Which leaves the question, Why might they not be? Is there anything besides the lack of experimental evidence to justify the title of the video being a question rather than a statement? (Of course, experimental evidence is a requirement of the scientific method, but.. you know how when they hype a particle, then you go and see the particle, and it's not as good as you were expecting...) P.S. A lot of people thought that about the Higgs.... But I thought it was a massive success. P.P.S. Sorry

  11. Amari Reyne

    Amari Reyne17 цагийн өмнө

    "The universe may be truly spatially infinite" Even though I already had that idea in my head, hearing the words out loud from someone else really melted my mind. There's so many things we will never even begin to understand before the heat death of our own part of the whole universe. I mean, we used to think the milky way was the whole universe. And we were calling Andromeda an "island universe" What's to make anyone think the universe we observe isn't just one of... Billions? Trillions? Infinite? Universes. Guess we will never know 🤷‍♂️ I havent slept in 27 hours, go easy on me if you reply 😅

  12. Zenothys

    Zenothys14 цагийн өмнө

    Amari Reyne You have a healthy skepticism and an inspiring curiosity. No reason to worry about responses imo! To give my two cents, space is only as large as needed to contain all possibilities (which I believe isn't infinite, but does inflate fast enough to redefine infinity to some larger number the instant the previous number is defined), and once you hit the "edge" of space, space becomes _time_ and more or less travels back to the Big Bang via the "beloved" Bogoliubov transformation.

  13. Cheasy

    Cheasy17 цагийн өмнө

    a nerd channel and no 60 fps xD yr tittle has been revoked

  14. Mtf

    Mtf18 цагийн өмнө

    I used to watch these videos and then, frustrated for not being able to understand, go to the pub . Now I 've thought better and I go to the pub BEFORE watching the videos and suddenly they are crystal clear .

  15. Doldol D

    Doldol D20 цагийн өмнө

    Really interesting episode

  16. frysebox1

    frysebox121 цагийн өмнө

    Me: Officer, why am I being detained? Officer: 2:18

  17. Lance Tschirhart

    Lance TschirhartӨдрийн өмнө

    Great apes _are_ monkeys. Jesus Christ, these cosmologists..

  18. Manu V

    Manu VӨдрийн өмнө

    Do I come here just to feel dumb!?

  19. Art

    ArtӨдрийн өмнө

    Had to downvote after the first two seconds :(

  20. Bill McDonough

    Bill McDonoughӨдрийн өмнө

    Matt, just to 'nerd all the way': the great apes (or Hominidae) are a Family within the infraorder Simiiformes... the monkeys. So strictly, all apes *are* monkeys. Catarrhini 'Old World' monkeys, in fact.

  21. Gabriel Desmarais

    Gabriel DesmaraisӨдрийн өмнө

    I guess it is official, we can't out-nerd Matt.

  22. Kez

    KezӨдрийн өмнө

    Can you be straight and wear a pink shirt into a gay bar?

  23. Jason Williams

    Jason WilliamsӨдрийн өмнө

    How can observable time not affect observable mass

  24. Nicolás Celedón

    Nicolás CeledónӨдрийн өмнө

    Did anyone read axioms and thought 'those damn matematicians'

  25. gusthebroken2

    gusthebroken2Өдрийн өмнө

    Jargon that no one understands .


    IBIS INFINITUSӨдрийн өмнө

    So I have a question... Do black holes change the topology of the fabric of space-time?

  27. Toni Kotinurmi

    Toni KotinurmiӨдрийн өмнө

    Doing physics in univ, for example speed of light (yeah, 30 years ago...) tests with rather strong lasers etc it was OK if we hit within 1e10..15 - just as long as we explained where error marginals came from. That latter part is more important than hitting target. So come on... If you measure something, do it again and again in different ways until you say it's inaccurate.

  28. Sammy Smith

    Sammy SmithӨдрийн өмнө

    You and the guy from Ancient Aliens are my heroes, so good information.

  29. Vistico93

    Vistico93Өдрийн өмнө

    An infinite universe means I would have an infinite number of tries to get my life right though only in an infinite number of them will I start off with memories of my previous attempts to do so...

  30. Nick Moraitis

    Nick MoraitisӨдрийн өмнө

    We can only need out to the fullest extent of our own universe.

  31. Mich ael

    Mich aelӨдрийн өмнө

    Next video: Are VPN services dark matter?

  32. C Apt

    C AptӨдрийн өмнө

    Answer below: How many seconds before you are lost on this video?

  33. BuhuBaha

    BuhuBahaӨдрийн өмнө

    In the Lagrangian at 5:17 in the last term one of the alphas should be a covariant index (: * Full nerd mode off * Great video though!

  34. Ri4s co

    Ri4s coӨдрийн өмнө

    What if dark matter is just an effect of dark energy pushing on gravity

  35. TheExpatpom

    TheExpatpomӨдрийн өмнө

    If axions, assuming they exist and are the dark matter physicists have been looking for, are produced in the core of fairly unremarkable star like our sun, is the next question why the stars in those dark matter free galaxies that have been discovered haven’t been producing axions? For that matter if loads of axions were produced during the Big Bang wouldn’t we expect them to end up in the same regions and structures as ordinary matter, and for there to be no galaxies without them? Or is there a possible answer that’s the subject of a future video?

  36. Mainland Empire Records

    Mainland Empire RecordsӨдрийн өмнө

    AHHAHA nerd all the way. Cone'd a phrase.

  37. Fundemort Grey Prime Defender of Truth and Justice

    Fundemort Grey Prime Defender of Truth and JusticeӨдрийн өмнө

    But Sheldon got his Nobel from Super-Asymmetry theory. (this is obv just a joke).

  38. Mainland Empire Records

    Mainland Empire RecordsӨдрийн өмнө

    I love this show. I started watching in 2018, and I haven't stopped since. Thank for you incredibly high value content.

  39. Tripcore

    TripcoreӨдрийн өмнө

    More 'infinite' nonsense

  40. Tripcore

    TripcoreӨдрийн өмнө

    Physical Value zero = virtual. Value of zero in physical world = does not exist.

  41. Tripcore

    TripcoreӨдрийн өмнө

    PBS: Aka 'nothing' Also pbs: 'nothing doesn't exist'.

  42. jojolafrite90

    jojolafrite902 өдрийн өмнө

    I really don't believe in the existence of what they called axions. And even less in "WIMPS". There are better solutions to our physics problems and we will understand one day. I do think we are limited by the realist view on what we observe, it's still a too common interpretation among physicists. And the fact that they all want to invent solutions to problems between what we can verify and what we expect to verify in a way that they seem to want our universe to be a closed system that exists in itself, and is not part of anything more.

  43. Tuco Benedicto

    Tuco Benedicto2 өдрийн өмнө

    I understood some of these words.

  44. Relbl

    Relbl2 өдрийн өмнө

    As long as you are on the "String Theory" path then we all know this leads to nothing... it's been 40yrs and no progress or discoveries. Is physics so sclerotic nowadays? or is it the sciences in general...?

  45. Genildo Miranda

    Genildo Miranda2 өдрийн өмнө

    OMG I am so dumb...

  46. Igor Tolstov

    Igor Tolstov2 өдрийн өмнө

    Physicists just love to make up different constants, fields, and particles to plug in holes in what they don’t understand

  47. Poultryphile

    Poultryphile2 өдрийн өмнө

    Would the duplicate universe have a duplicate Matt presenting another, equally awesome, Spacetime show?

  48. Gordon Gecko

    Gordon Gecko2 өдрийн өмнө

    Hey Tyrion Lannister are dragons real?

  49. Captain Caveman

    Captain Caveman2 өдрийн өмнө

    Hmmmm did I just see you on "the way the universe works" ?? Does the universe have a boundary episode.

  50. Punk Patriot

    Punk Patriot2 өдрийн өмнө

    This video, my level of understanding kept oscillating between feeling like I am starting to get it, to feeling like you are speaking Klingon.

  51. stat a87c

    stat a87c2 өдрийн өмнө

    I hear alot that a quantum fluctuation is suspected to have sparked the big bang...but there was no space, and therefore no time before the big tf can something fluctuate without time, and without a dimension to fluctuate in??

  52. Faint

    Faint2 өдрийн өмнө

    drink everytime he puts his hands back together

  53. Supersad Cat

    Supersad CatӨдрийн өмнө

    Okay, even chickens can join Team Cat.

  54. Gareth Wigglesworth

    Gareth Wigglesworth2 өдрийн өмнө

    do black holes contribute to the expansion of space time?

  55. Division Zero

    Division Zero2 өдрийн өмнө

    the frame rate was a bit of annoying ngl

  56. Follower of Julian

    Follower of Julian2 өдрийн өмнө

    16:08 Latin pronunciation changes over time and from place to place. This is a problem singers face constantly. It's sad that, for all the great work that you do, THIS is all people notice! Μὴ δῶτε τὸ ἅγιον τοῖς κυσὶν μηδὲ βάλητε τοὺς μαργαρίτας ὑμῶν ἔμπροσθεν τῶν χοίρων μήποτε καταπατήσουσιν αὐτοὺς ἐν τοῖς ποσὶν αὐτῶν καὶ στραφέντες ῥήξωσιν ὑμᾶς.

  57. Leslie Schwartz

    Leslie Schwartz2 өдрийн өмнө

    A complete total fantasy speculation, this isn't science.

  58. MikeOfNotts

    MikeOfNotts2 өдрийн өмнө

    You are looking for a useless cloud of matter that is only big enough to fill the hole in your equations. Maybe it's bigger that that.

  59. Reyna Lindström

    Reyna Lindström2 өдрийн өмнө

    the last one was so funny!

  60. LashknifeTalon

    LashknifeTalon2 өдрийн өмнө

    Good job guys, we made him give up on pronouncing that thing that Newton wrote.

  61. Kazimir

    Kazimir2 өдрийн өмнө

    Could someone pls make a anthropomorphized cartoon about quantum particle behavior to make this understandable? There is so much going on in nearly anything. From vacuum to simple atoms. Quarks, Leptons, Bosons and so on... I'm clearly not able to imagine what is going on anymore. Sure, I could eat some shrooms, but damn. Can anyone put this together to make a clear image to look at? Like oldschool 60's atoms, just by modern standards. I have seen so many visualizations of "this", but it is really hard to put it in some context. So how many dimensions do I need to understand gravity in its simplest form - 11?

  62. W_Sindarius

    W_Sindarius2 өдрийн өмнө

    Nice video, as usual, but I wish you guys would lose the music. Makes it seem less ... authentic.