Ramsey Theory Introduction

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  • เผยแพร่เมื่อ 11 ก.ค. 2024
  • en.wikipedia.org/wiki/Ramsey%...
    Avoiding triangles is not as easy as it may seem.
    SUBSCRIBE if you enjoy this video!

ความคิดเห็น • 71

  • @williamgallop9425
    @williamgallop9425 ปีที่แล้ว +37

    Mathematician Paul Erdős once said that if aliens landed on Earth and demanded a precise Ramsey number for 5 or they'd destroy the planet, humanity should divert all of its computing resources to figure out the answer. But if they demanded the Ramsey number for 6, humans should prepare for war.

    • @hunterrehm6165
      @hunterrehm6165  ปีที่แล้ว +5

      What a great quote! This is a great field of research. I haven't studied Ramsey numbers in particular, but I have looked in to Anti-van der Waerden numbers and Schur numbers!

    • @realshimmerstudios
      @realshimmerstudios 2 หลายเดือนก่อน

      @@hunterrehm6165 i don't understand how they don't know the ramsey numbers for 6, can't you just brute force the solution with programming? I mean, with enough computing power, you can surely make an algorithm to check every possiblity for each number.

    • @brendawilliams8062
      @brendawilliams8062 4 วันที่ผ่านมา

      Honey, you’d best get ready to hit the bad lands for that one.

  • @philiprabintagapan3870
    @philiprabintagapan3870 2 ปีที่แล้ว +20

    this explanation is simpler than the one i read on the book. thanks dude

  • @benjaminrabiego1121
    @benjaminrabiego1121 3 ปีที่แล้ว +6

    Great vid. Thanks for sharing!

    • @hunterrehm6165
      @hunterrehm6165  3 ปีที่แล้ว +2

      Thanks! I hope to post more soon.

  • @emilymerian42
    @emilymerian42 3 ปีที่แล้ว +5

    So glad I found your videos!!

  • @ofek8280
    @ofek8280 7 หลายเดือนก่อน +1

    beautiful video! just started learning this ,Thank you!

    • @hunterrehm6165
      @hunterrehm6165  5 หลายเดือนก่อน +1

      Thank you! I’ll be coming out with a new video soon I hope

  • @notuwuzi6948
    @notuwuzi6948 ปีที่แล้ว +1

    wow, super underated. subscribing time!

    • @hunterrehm6165
      @hunterrehm6165  ปีที่แล้ว

      Welcome aboard! I just finished my PhD, so I will be making video more now. What would you like to see? More videos like this one?

  • @Jacquelinekarlsson_
    @Jacquelinekarlsson_ 2 ปีที่แล้ว +5

    This was so good and helpful, thankyou 😄

    • @hunterrehm6165
      @hunterrehm6165  2 ปีที่แล้ว

      Love to hear it! I am currently getting my PhD so video production is slow, but I hope you subscribed!

  • @megamac3664
    @megamac3664 2 หลายเดือนก่อน

    Banger video man I love math

  • @Zoppyification
    @Zoppyification 2 ปีที่แล้ว +19

    Very simple and clear explanation, thanks!

    • @hunterrehm6165
      @hunterrehm6165  2 ปีที่แล้ว +3

      Glad you said something! It means a lot!

  • @shivkarj1456
    @shivkarj1456 2 ปีที่แล้ว +5

    Great video!! Nice to see people using the manim engine.

    • @hunterrehm6165
      @hunterrehm6165  2 ปีที่แล้ว +3

      Thanks! Yeah it’s nice and easy to make some really great animations. Have you tried it?

    • @shivkarj1456
      @shivkarj1456 2 ปีที่แล้ว +2

      @@hunterrehm6165 Not really. But its nice to see the community making good of it.

  • @brentdassow1040
    @brentdassow1040 3 ปีที่แล้ว +2

    background music is fire🔥10/10 vid

  • @logicmatthewlearning
    @logicmatthewlearning ปีที่แล้ว +2

    Thank you! Now I understand!

  • @clonebin0
    @clonebin0 3 ปีที่แล้ว +3

    Very good video!

  • @mikesnelling9272
    @mikesnelling9272 2 ปีที่แล้ว +4

    excellent clear explanation

  • @bowser7878
    @bowser7878 8 หลายเดือนก่อน

    Thanks Hunter. Good video

    • @hunterrehm6165
      @hunterrehm6165  8 หลายเดือนก่อน

      You bet! Let me know if there is a topic you are interested in seeing. I can try to make something on it.

  • @jaimejdtrechuelo1696
    @jaimejdtrechuelo1696 5 หลายเดือนก่อน +1

    Such a great video

  • @fatimazahra7648
    @fatimazahra7648 ปีที่แล้ว +1

    this is amazing

  • @pcmtutorials
    @pcmtutorials ปีที่แล้ว

    Thanks for the simplest presentation.:)

    • @hunterrehm6165
      @hunterrehm6165  ปีที่แล้ว +1

      Oh its my pleasure. Are you interested in graph theory?

    • @pcmtutorials
      @pcmtutorials ปีที่แล้ว

      @@hunterrehm6165 I've taught graph theory on my youtube channel already 😊

    • @hunterrehm6165
      @hunterrehm6165  ปีที่แล้ว

      @@pcmtutorials Awesome! I just checked it out! Love it!

  • @guyst4188
    @guyst4188 11 หลายเดือนก่อน

    Great video

    • @hunterrehm6165
      @hunterrehm6165  9 หลายเดือนก่อน

      Thank you so much! Let me know if there is another topic that interests you!

  • @rajnikantsharma4054
    @rajnikantsharma4054 3 ปีที่แล้ว +2

    Awesome

  • @maxdemuynck9850
    @maxdemuynck9850 ปีที่แล้ว

    awesome video!!

    • @hunterrehm6165
      @hunterrehm6165  ปีที่แล้ว

      Glad to hear you enjoyed it! Are you interested in graph theory like me?

    • @maxdemuynck9850
      @maxdemuynck9850 ปีที่แล้ว +1

      it seems very interesting! I don't know much about it just happened to come across your channel because we used it in analysis as part of a proof of Bolzano weierstrauss

    • @hunterrehm6165
      @hunterrehm6165  ปีที่แล้ว

      @@maxdemuynck9850 Wow that is interesting. It has been a bit since I have seen Bolzano-Weierstrass, but I am surprised to here Ramsey theory was in the proof. Would love to hear more!

  • @galcesana8603
    @galcesana8603 ปีที่แล้ว +3

    thanks!!

    • @hunterrehm6165
      @hunterrehm6165  ปีที่แล้ว +1

      Glad you enjoyed it! Let me know if there are any other topics you would like to see!

  • @DukeNukem713
    @DukeNukem713 6 หลายเดือนก่อน

    If I claim R(5,5) = 72 what can be used to prove it wrong?

  • @Itay12353
    @Itay12353 3 ปีที่แล้ว +1

    very helpfull

    • @hunterrehm6165
      @hunterrehm6165  3 ปีที่แล้ว

      Thank you! Stay tuned for more videos!

  • @kelseyyyy4
    @kelseyyyy4 ปีที่แล้ว +1

    riveting 🧐

    • @hunterrehm6165
      @hunterrehm6165  ปีที่แล้ว +1

      It doesn't get much better than this!

  • @Anistuffs
    @Anistuffs ปีที่แล้ว +2

    5:50 You forgot to put the link :(

    • @hunterrehm6165
      @hunterrehm6165  ปีที่แล้ว

      I just added the link in the description! It's just the wiki page, but it does a good job summarizing the known values.

  • @pascals5408
    @pascals5408 2 ปีที่แล้ว +3

    I don't understand how the pidgeon hole principle helps us with the coloring at 3:40

    • @hunterrehm6165
      @hunterrehm6165  2 ปีที่แล้ว +2

      @hisocar I think of the colors as the bins and the edges as the pigeons. This way, by the (generalized) pigeonhole principle, three of the edges must be colored the same. Does that make sense?

    • @madghostek3026
      @madghostek3026 2 ปีที่แล้ว

      The idea is that nobody forces you to pick 3 red and 2 blue, you can try doing 5 red 0 blue, but no matter what, there always will be at least 3 people connecting to first person, that have same color, lets call them A B and C. This allows constructing the white triangle, at which point we are helpless, no matter what you color the triangle, you either create same color edge between first person and 2 from ABC, or if you try to avoid this situation by not giving same color at all... the white triangle becomes what you wanted to avoid, it has only one color!

    • @Anistuffs
      @Anistuffs ปีที่แล้ว +4

      A bit late, but if you're still having trouble, I think I got what Rehm meant.
      So for 1 person knowing or not knowing 5 others, from their POV, they can only have any one of the following possible mutually exclusive options:
      1. Know all 5
      2. Know 4, and not know 1
      3. Know 3, and not know 2
      4. Know 2, and not know 3
      5. Know 1, and not know 4
      6. Not know all 5
      At 3:19, Rehm claims that using Pigeonhole principle, that person knows at least 3 people or not know at least 3 people.
      You can go through all 6 options listed above and see that, in every case, Rehm's claim is true.
      I'm not fully sure how the Pigeonhole principle is used here, but the ultimate claim is correct.

    • @pcmtutorials
      @pcmtutorials ปีที่แล้ว +1

      Use extended form of Pigeonhole principle i.e. [(n-1)/m] +1...... n=5 and m=2 .. Therefore, [(5-1)/2] +1= 3

  • @johnashton9678
    @johnashton9678 2 ปีที่แล้ว

    Well, I um. I'll try watching again without drink in my brain.

    • @hunterrehm6165
      @hunterrehm6165  2 ปีที่แล้ว

      Haha let me know if you have any questions! Happy to help.

  • @zeydbahadir
    @zeydbahadir ปีที่แล้ว +1

    Where is the link below?

    • @hunterrehm6165
      @hunterrehm6165  ปีที่แล้ว

      My bad. I just added the link to the wiki page in the description. There is a table there which summarizes the known values!

  • @stevegao2888
    @stevegao2888 2 ปีที่แล้ว +1

    Please use the regular way to show your text.thx

    • @hunterrehm6165
      @hunterrehm6165  ปีที่แล้ว

      I will do this for future videos probably!

  • @shreyaskrishna6038
    @shreyaskrishna6038 2 ปีที่แล้ว +1

    Why can't everyone not know eachother though? Ie, all blue?

    • @hunterrehm6165
      @hunterrehm6165  2 ปีที่แล้ว +1

      The theorem states that with 6 people in a room, either 3 people know each other, or 3 people do not. So if 3 people do not know each other, then the theorem is satisfied and we should consider the next case. That proof really just shows that there will necessarily be a monochromatic K_3 in every 2-edge-coloring of a K_6.

  • @shahidsafeer6115
    @shahidsafeer6115 4 หลายเดือนก่อน

    Thank u sir love and support from Pakistan ❤