a nice result from Ramanujan's "lost notebook"

แชร์
ฝัง
  • เผยแพร่เมื่อ 11 ก.พ. 2025
  • 🌟Support the channel🌟
    Patreon: / michaelpennmath
    Channel Membership: / @michaelpennmath
    Merch: teespring.com/...
    My amazon shop: www.amazon.com...
    🟢 Discord: / discord
    🌟my other channels🌟
    mathmajor: / @mathmajor
    pennpav podcast: / @thepennpavpodcast7878
    🌟My Links🌟
    Personal Website: www.michael-pen...
    Instagram: / melp2718
    Twitter: / michaelpennmath
    Randolph College Math: www.randolphcol...
    Research Gate profile: www.researchga...
    Google Scholar profile: scholar.google...
    🌟How I make Thumbnails🌟
    Canva: partner.canva....
    Color Pallet: coolors.co/?re...
    🌟Suggest a problem🌟
    forms.gle/ea7P...

ความคิดเห็น • 37

  • @Mephisto707
    @Mephisto707 5 วันที่ผ่านมา +24

    How genius Ramanujam was? He thought of hundreds of hard problems like this that nobody asked before and solved them just for the sake of it.

    • @mrhatman675
      @mrhatman675 5 วันที่ผ่านมา +1

      He wasn't t a genius he said god whispered him these ideas ramanujan just implemented them

    • @forcelifeforce
      @forcelifeforce 5 วันที่ผ่านมา

      @@mrhatman675 * *Ramanujan* His name is capitalized, just as your actual name is.

    • @mrhatman675
      @mrhatman675 5 วันที่ผ่านมา +4

      @@forcelifeforce who cares

    • @SuperSilver316
      @SuperSilver316 5 วันที่ผ่านมา

      Both a genius and god spoke to him

    • @mrhatman675
      @mrhatman675 5 วันที่ผ่านมา

      @@SuperSilver316 No god told him the ideas ramanujan just implemented them

  • @MooImABunny
    @MooImABunny 5 วันที่ผ่านมา +15

    so basically Ramanujan's approach was "here's a complicated expression, I'll just make a way more complicated version of the same, find a way to connect the more complicated versions in a chain of relationships, and the fact that this chain is infinite somehow lets us push the last infinitely complicated term out of relevance. And bonus points for actually converging sometimes"

    • @MooImABunny
      @MooImABunny 5 วันที่ผ่านมา +5

      In terms of ancient memes, Yo dawg I heard you liked infinity, so we put infinity inside your infinity, so you can formal series while you formal series

  • @Tabu11211
    @Tabu11211 5 วันที่ผ่านมา +4

    That was actually such a trip!

  • @MathFromAlphaToOmega
    @MathFromAlphaToOmega 3 วันที่ผ่านมา

    I don't know much about power series where the exponents have degree higher than 2, but one of the main reasons that sums like Σx^n^2 have been studied so much is due to their connection with modular forms (in particular, theta functions). The most basic theta function identities come from the Gaussian integral ∫e^(-x^2)dx, and that's where the square exponents come from.

  • @SuperSilver316
    @SuperSilver316 5 วันที่ผ่านมา +4

    Looks another result that we can use to show that Grandi’s series has an Abel Sum of 1/2.

  • @goodplacetostop2973
    @goodplacetostop2973 5 วันที่ผ่านมา +11

    20:46

  • @Kram1032
    @Kram1032 4 วันที่ผ่านมา +1

    Each individual step is quite simple but the amount of work it must have taken to figure out this particular order of steps and clarify them must've been insane. Just endless playing with slightly different forms.
    The way you put it here is pretty structured. I bet originally it very much was not.

  • @Freud_Sigmund
    @Freud_Sigmund 5 วันที่ผ่านมา +3

    Bro really knew infinity

  • @rocky171986
    @rocky171986 5 วันที่ผ่านมา +5

    Missing a step to show that L_n tends to zero for n tending to infinity, in the radius for mod x less than 1.

    • @MooImABunny
      @MooImABunny 5 วันที่ผ่านมา +3

      it's left as a trivial exercise for the reader

    • @checkmatedino9543
      @checkmatedino9543 5 วันที่ผ่านมา +1

      The margins of the notebook were too small

    • @drorbitaldeathray
      @drorbitaldeathray 5 วันที่ผ่านมา

      Ramanujan in a nutshell

  • @htpc002Weirdhouse
    @htpc002Weirdhouse 5 วันที่ผ่านมา +2

    Typo' in original left-hand side, third numerator: "(1-x^2)" should be "(1-x^3)".

    • @OrbitTheSun
      @OrbitTheSun 5 วันที่ผ่านมา +1

      My numerical analysis can confirm you. I previously had a deviation between the convergence values. - Thanks for the correction.

  • @pow3rofevil
    @pow3rofevil 5 วันที่ผ่านมา +1

    Me parece maravilloso tu contenido estimado, saludos desde chile

  • @ahmedlutfi4894
    @ahmedlutfi4894 3 วันที่ผ่านมา

    19:17 forgot to write ( - x^8)

  • @PULLABHATLAMEDHA
    @PULLABHATLAMEDHA 5 วันที่ผ่านมา +3

    Wow

  • @Alan-zf2tt
    @Alan-zf2tt 5 วันที่ผ่านมา

    wow!

  • @gp-ht7ug
    @gp-ht7ug 5 วันที่ผ่านมา

    Obscure

  • @checkmatedino9543
    @checkmatedino9543 5 วันที่ผ่านมา

    I cant see the pattern in the question though

  • @WispWorld
    @WispWorld 5 วันที่ผ่านมา

    cant understand but cant look away either^^

  • @MathPhysicsScience-tg6ox
    @MathPhysicsScience-tg6ox 4 วันที่ผ่านมา

    I like the chalk colorscheme on this channel. Looks like xoria256.

  • @TomFarrell-p9z
    @TomFarrell-p9z 5 วันที่ผ่านมา

    Gee, there's a much simpler way to show this....nah, just kidding!

  • @myfreakingaccount
    @myfreakingaccount 5 วันที่ผ่านมา +1

    I guess "hypergeometric series" is a misnomer here, because it is generally referred to another thing (en.wikipedia.org/wiki/Hypergeometric_function#The_hypergeometric_series). The series in the RHS of the identity actually resembles that of a version of theta function

    • @winnablebtw459
      @winnablebtw459 4 วันที่ผ่านมา

      I believe he meant 'basic hypergeometric series' which are essentially q-analogs of hypergeometric series.

  • @alipourzand6499
    @alipourzand6499 5 วันที่ผ่านมา

    Ramanujam style! No sympy, no mathcad, no mapple, ...

    • @TomFarrell-p9z
      @TomFarrell-p9z 5 วันที่ผ่านมา +2

      Wonder if he at least had multi-colored chalk?

    • @forcelifeforce
      @forcelifeforce 5 วันที่ผ่านมา

      Please write in English words.

    • @donach9
      @donach9 4 วันที่ผ่านมา

      ​@@forcelifeforcethey are. Those are maths programs, tho I assume they've spelt maple incorrectly