What is Math?
What is Math?
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Differential Geometry - 17 - Comparison Geometry (again) x Toponogov Theorem
What is Differential Geometry? Curves and Surfaces is a course in basic differential geometry focused on problem solving and aimed towards research level geometry.
arxiv.org/abs/2012.11814
Proof of Toponogov Theorem by Lang and Schroeder:
Lang, U., & Schroeder, V. (2013). On Toponogov’s comparison theorem for Alexandrov spaces. Enseign. Math, 59(3-4), 325-336.
A very similar proof was found independently by Stephanie Alexander, Vitali Kapovitch, and Anton Petrunin
arxiv.org/abs/1903.08539
Riemannian geometry by Lee: www.maths.ed.ac.uk/~v1ranick/papers/leeriemm.pdf
Metric geometry by Burago, Burago, and Ivanov:
web.archive.org/web/20140211152148id_/www.math.psu.edu:80/petrunin/papers/alexandrov/bbi.pdf
Differential forms in algebraic topology by Bott and Tu:
link.springer.com/book/10.1007/978-1-4757-3951-0
This video was animated using the Manim extension of Python, developed by the Manim community, and originally created by Grant Sanderson: github.com/ManimCommunity/manim
The code used for this video can be found in the repository: github.com/zamorabarser/DiffGeo-Videos
Music:
Dream in Am - Rand Aldo
Happy Minor Walz - Franz Gordon
The Inventor - David Celeste
Last Song of the Night - Rachel Meyer
Wayfinders - Trevor Kowalski
Lullaby - Speedy the Spider
Happy Death - Torii Wolf
มุมมอง: 684

วีดีโอ

Differential Geometry - 16 - Flat Surfaces x Comparison Geometry
มุมมอง 6116 หลายเดือนก่อน
What is Differential Geometry? Curves and Surfaces is a course in basic differential geometry focused on problem solving and aimed towards research level geometry. arxiv.org/abs/2012.11814 Pogorelov, A. V. (1964). Some results on surface theory in the large. Advances in mathematics, 1(2), 191-264. Hartman, P., & Nirenberg, L. (1959). On spherical image maps whose Jacobians do not change sign. A...
Differential Geometry - 15 - Parallel Transport x Gauss-Bonnet Theorem
มุมมอง 2.7K10 หลายเดือนก่อน
What is Differential Geometry? Curves and Surfaces is a course in basic differential geometry focused on problem solving and aimed towards research level geometry. arxiv.org/abs/2012.11814 This video was animated using the Manim extension of Python, developed by the Manim community, and originally created by Grant Sanderson: github.com/ManimCommunity/manim The code used for this video can be fo...
Differential Geometry - 14 - Jacobi Equation x Theorema Egregium
มุมมอง 89611 หลายเดือนก่อน
What is Differential Geometry? Curves and Surfaces is a course in basic differential geometry focused on problem solving and aimed towards research level geometry. arxiv.org/abs/2012.11814 This video was animated using the Manim extension of Python, developed by the Manim community, and originally created by Grant Sanderson: github.com/ManimCommunity/manim The code used for this video can be fo...
Cayley graph examples
มุมมอง 1.4Kปีที่แล้ว
This video was animated using the Manim extension of Python, developed by the Manim community, and originally created by Grant Sanderson github.com/ManimCommunity/manim
Differential Geometry - 13 - Minimizing Curves x Geodesics
มุมมอง 924ปีที่แล้ว
What is Differential Geometry? Curves and Surfaces is a course in basic differential geometry focused on problem solving and aimed towards research level geometry. arxiv.org/abs/2012.11814 This video was animated using the Manim extension of Python, developed by the Manim community, and originally created by Grant Sanderson: github.com/ManimCommunity/manim The code used for this video can be fo...
Differential Geometry - 12 - Surfaces of Revolution x Lagunov's Fishbowl
มุมมอง 1.1Kปีที่แล้ว
What is Differential Geometry? Curves and Surfaces is a course in basic differential geometry focused on problem solving and aimed towards research level geometry. arxiv.org/abs/2012.11814 This video was animated using the Manim extension of Python, developed by the Manim community, and originally created by Grant Sanderson: github.com/ManimCommunity/manim The code used for this video can be fo...
Differential Geometry - 11 - Gauss Map x Gauss Curvature
มุมมอง 7Kปีที่แล้ว
What is Differential Geometry? Curves and Surfaces is a course in basic differential geometry focused on problem solving and aimed towards research level geometry. arxiv.org/abs/2012.11814 This video was animated using the Manim extension of Python, developed by the Manim community, and originally created by Grant Sanderson: github.com/ManimCommunity/manim The code used for this video can be fo...
Differential Geometry - 10 - Calculus x Tangent Planes
มุมมอง 1.4Kปีที่แล้ว
What is Differential Geometry? Curves and Surfaces is a course in basic differential geometry focused on problem solving and aimed towards research level geometry. arxiv.org/abs/2012.11814 This video was animated using the Manim extension of Python, developed by the Manim community, and originally created by Grant Sanderson: github.com/ManimCommunity/manim The code used for this video can be fo...
Differential Geometry - 9 - Surfaces x Charts
มุมมอง 2.3Kปีที่แล้ว
What is Differential Geometry? Curves and Surfaces is a course in basic differential geometry focused on problem solving and aimed towards research level geometry. arxiv.org/abs/2012.11814 This video was animated using the Manim extension of Python, developed by the Manim community, and originally created by Grant Sanderson: github.com/ManimCommunity/manim The code used for this video can be fo...
Differential Geometry - 8 - Supporting Curves x Osculating Circles
มุมมอง 1.2Kปีที่แล้ว
What is Differential Geometry? Curves and Surfaces is a course in basic differential geometry focused on problem solving and aimed towards research level geometry. arxiv.org/abs/2012.11814 This video is also based on the paper "Moon in a puddle and the four-vertex theorem" by Anton Petrunin and Sergio Zamora. arxiv.org/pdf/2107.08455.pdf This video was animated using the Manim extension of Pyth...
Differential Geometry - 6 - Spherical Curves x Fenchel Theorem
มุมมอง 1.8Kปีที่แล้ว
What is Differential Geometry? Curves and Surfaces is a course in basic differential geometry focused on problem solving and aimed towards research level geometry. arxiv.org/abs/2012.11814 This video was animated using the Manim extension of Python, developed by the Manim community, and originally created by Grant Sanderson: github.com/ManimCommunity/manim The code used for this video can be fo...
Differential Geometry - 7 - Signed Curvature x Turning Tangents
มุมมอง 1.5Kปีที่แล้ว
What is Differential Geometry? Curves and Surfaces is a course in basic differential geometry focused on problem solving and aimed towards research level geometry. arxiv.org/abs/2012.11814 This video was animated using the Manim extension of Python, developed by the Manim community, and originally created by Grant Sanderson: github.com/ManimCommunity/manim The code used for this video can be fo...
Differential Geometry - 2 - Length x Arc Length Parametrization
มุมมอง 5Kปีที่แล้ว
What is Differential Geometry? Curves and Surfaces is a course in basic differential geometry focused on problem solving and aimed towards research level geometry. arxiv.org/abs/2012.11814 This video was animated using the Manim extension of Python, developed by the Manim community, and originally created by Grant Sanderson: github.com/ManimCommunity/manim The code used for this video can be fo...
Differential Geometry - 5 - Curvature x Total Curvature
มุมมอง 1.9Kปีที่แล้ว
What is Differential Geometry? Curves and Surfaces is a course in basic differential geometry focused on problem solving and aimed towards research level geometry. arxiv.org/abs/2012.11814 This video was animated using the Manim extension of Python, developed by the Manim community, and originally created by Grant Sanderson: github.com/ManimCommunity/manim The code used for this video can be fo...
Differential Geometry - 4 - Crofton Formula x 3D Curves
มุมมอง 2.1Kปีที่แล้ว
Differential Geometry - 4 - Crofton Formula x 3D Curves
Differential Geometry - 3 - Smooth Curves x Length Formula
มุมมอง 3Kปีที่แล้ว
Differential Geometry - 3 - Smooth Curves x Length Formula
Differential Geometry - 1 - Curves x Definitions and Technicalities
มุมมอง 17Kปีที่แล้ว
Differential Geometry - 1 - Curves x Definitions and Technicalities
Lower Semicontinuity of the Fundamental Group and Convergence with Discrete Symmetry.
มุมมอง 4454 ปีที่แล้ว
Lower Semicontinuity of the Fundamental Group and Convergence with Discrete Symmetry.

ความคิดเห็น

  • @wargreymon2024
    @wargreymon2024 วันที่ผ่านมา

    if you show only the definition without walking through, I would rather read articles.

  • @aboveskyphysics
    @aboveskyphysics 11 วันที่ผ่านมา

    Good video! Just a minor thing: at 2:55, the movement of the point doesn't match given equations. It should be at the origin for t=-infty, go to the left side at infty as t goes to 0-, jump to the origin for t=0 and then flip to the right part at infty for t=0+, and back to 0 as t goes to +infty. It is therefore not continuous in 0. But we get the idea and it is easy to build the desired mapping from there. 😊

    • @what-is-math
      @what-is-math 11 วันที่ผ่านมา

      You made me doubt myself 😅 But they are correct! As t approaches 0 from the left, 1/t is very negative, therefore e^(1/t) is close to 0.

    • @aboveskyphysics
      @aboveskyphysics 11 วันที่ผ่านมา

      @@what-is-math You are perfectly right. My comment was indeed totally stupid, sorry about that!

    • @what-is-math
      @what-is-math 11 วันที่ผ่านมา

      It took me a while to realize what was going on too :P

  • @rwharrington87
    @rwharrington87 12 วันที่ผ่านมา

    0:54 haha. Unfortunately.

  • @tysoninnes3870
    @tysoninnes3870 29 วันที่ผ่านมา

    Crazy that this series has so few views, great stuff

  • @hyperduality2838
    @hyperduality2838 2 หลายเดือนก่อน

    Positive curvature (dark matter, synergy) is dual to negative curvature (dark energy). Curvature is dual. Contravariant is dual to covariant -- vectors or functors -- dual basis. Attraction is dual to repulsion -- forces are dual! "Always two there are" -- Yoda.

  • @minma02262
    @minma02262 2 หลายเดือนก่อน

    HOLLY MOLLY! THANK YOU! THANK YOU! THANK YOU!

  • @Sovagamer
    @Sovagamer 3 หลายเดือนก่อน

    Can you give a hint how to solve the problem near the end of the lecture, I dont understand how I should use deltas

  • @barak363363
    @barak363363 4 หลายเดือนก่อน

    Just in time! I really needed that! Thanks!

  • @alfredo970
    @alfredo970 4 หลายเดือนก่อน

    You deserve more subscribers

  • @nikossnx6957
    @nikossnx6957 4 หลายเดือนก่อน

    Your explanation and together with the animations were superb! Thank you for helping me understand this.

  • @brofessorsbooks3352
    @brofessorsbooks3352 5 หลายเดือนก่อน

    AMAZING

  • @DivineScaleOfGod
    @DivineScaleOfGod 5 หลายเดือนก่อน

    The piano song was beautiful

    • @what-is-math
      @what-is-math 5 หลายเดือนก่อน

      Prairie Song - Gavin Luke

  • @xuan5280
    @xuan5280 6 หลายเดือนก่อน

    Very helpful video

  • @what-is-math
    @what-is-math 6 หลายเดือนก่อน

    15:16 the sequence |r_n - s_n| goes to zero, not infinity!!!

  • @Giganesh_exe
    @Giganesh_exe 6 หลายเดือนก่อน

    you helped me get a 75% on my Differential Geometry Exam and a distinction in the course! Ty so much for this amazing playlist, hope it keeps continuing!!

  • @AllemandInstable
    @AllemandInstable 6 หลายเดือนก่อน

    18 views, glad I'm being recommended this video somehow, seems like I managed to build my youtube algorithm the way I want it to be 😆 nice video, a lot of efforts had to be put in, please continue !

  • @TheJara123
    @TheJara123 6 หลายเดือนก่อน

    Cool man thanks

  • @TheJara123
    @TheJara123 6 หลายเดือนก่อน

    Marvelous man...keep.up

  • @tim-701cca
    @tim-701cca 6 หลายเดือนก่อน

    7:06 <S(v), v>=<N,r''(0)> that shows the relations to Normal Curvature and 2nd fund.form. This helps!

  • @MertowVA
    @MertowVA 9 หลายเดือนก่อน

    Fantastic visualizations. Great work! Also great use of manim.

  • @schobihh2703
    @schobihh2703 10 หลายเดือนก่อน

    Really? I studied math and know differential geometry. Therefore I know what you are talking of. That is why I can say, that the whole video is merely a sum o quotations of some text book. Watching is worthless.

    • @1e8htvah
      @1e8htvah 3 หลายเดือนก่อน

      i can very much sympathise with the frustration of retrospectively seeing how much easier learning could be with improved pedagogy, but at the same time i think these videos are (personally) far better than anything else i've found and its bewildering to me that they all have views in the 100's / 1000's. I hope comments like these dont discourage you @what-is-math, as its glaringly self-evident to me that the lack of popularity of these videos has little to do with the quality and content

  • @bradzoltick6465
    @bradzoltick6465 10 หลายเดือนก่อน

    I wish you would drop the background music. It is both distracting and annoying. Otherwise, your animations are beautiful. Great job.

    • @what-is-math
      @what-is-math 10 หลายเดือนก่อน

      Thank you. The real problem is my editing skills. Trying to get better at that specifically

    • @Abdalrhman_Kilesee
      @Abdalrhman_Kilesee 5 หลายเดือนก่อน

      I agree

  • @BCarli1395
    @BCarli1395 10 หลายเดือนก่อน

    Thank you. Well done.

  • @okplay9446
    @okplay9446 10 หลายเดือนก่อน

    Blessed be the algorithm for recommending me this video. Best believe the Diff Geometry Playlist is going in my watch-later list. I'm still an undergraduate, but hopefully in a year or two I could use it as sumplementary material.

    • @what-is-math
      @what-is-math 10 หลายเดือนก่อน

      Best of luck in your courses!

  • @mightyowl1252
    @mightyowl1252 10 หลายเดือนก่อน

    These videos are really well made, I hope you make more of them. The explanations are very clear and the visual examples are great

  • @sharvani_0779
    @sharvani_0779 11 หลายเดือนก่อน

    00:03 Smooth functions on surfaces can be defined using charts and composition 01:08 Introduction to tangent planes 02:10 The tangent plane to Sigma at P is obtained by considering the set of older velocity vectors at Time Zero. 03:13 The tangent plane to segment p is contained in the set of velocity vectors of curves passing through b. 04:12 Derivatives of smooth functions for a smooth function f 05:18 The quantity on the left is independent of gamma and depends linearly on the coefficients of w. 06:21 Jacobian is defined as the length of the cross product of partial derivatives 07:20 Differential geometry uses parametrization to integrate over regions in R2.

  • @DSieh
    @DSieh 11 หลายเดือนก่อน

    High quality

  • @what-is-math
    @what-is-math 11 หลายเดือนก่อน

    At 11:23, in the last line of the Theorem, it should be gamma_{u,v,a,b} instead of phi_{u,v,a,b}. The geodesic curvature should be denoted by k_g, not k_{\gamma}.

  • @TheJara123
    @TheJara123 ปีที่แล้ว

    amazing series but where are the views? damn algorithm...

    • @oleksandrkaleniuk7813
      @oleksandrkaleniuk7813 3 หลายเดือนก่อน

      I've been thinking about it just the other day. 600 views for a content such as this is not that few. It's about the same as 20 years of teaching in a classroom.

  • @fuziyang7502
    @fuziyang7502 ปีที่แล้ว

    Really good tutorial. Thanks for making this.

  • @hiimkyle1894
    @hiimkyle1894 ปีที่แล้ว

    I don't understand this at all 😎

    • @samevans4834
      @samevans4834 ปีที่แล้ว

      Essentially, the set on the left defines a set of positions, and the set on the right defines “legal moves” between those positions. The animation just graphs them so you get a better intuition.

    • @what-is-math
      @what-is-math ปีที่แล้ว

      I used these pictures for a presentation, but I liked it so I decided to put it here as well :P Someday soon I will upload a way longer version with explanations ;)

  • @YEWCHENGYINMoe
    @YEWCHENGYINMoe ปีที่แล้ว

    first comment

  • @notpalmtrees
    @notpalmtrees ปีที่แล้ว

    This is so well explained!

  • @nikolaskaarsberg7754
    @nikolaskaarsberg7754 ปีที่แล้ว

    This is easily the best video I've seen on this topic. Great explanations and the visuals help so much. Great video!

  • @jjw4832
    @jjw4832 ปีที่แล้ว

    Really well made. Concise and clear explanations.

  • @кархарт-п6я
    @кархарт-п6я ปีที่แล้ว

    Like

  • @dylanparker130
    @dylanparker130 ปีที่แล้ว

    Love this, especially the stuff about modeling a surface by parallels and meridians

  • @unkn0wnus3r97
    @unkn0wnus3r97 ปีที่แล้ว

    excellent video!

  • @AllemandInstable
    @AllemandInstable ปีที่แล้ว

    keep on going ! 💯🥳

  • @wipperod
    @wipperod ปีที่แล้ว

    Hi, I just started using Manim and I was wondering if you could share a piece of code that you used to move the tangent vector T along the curve?

    • @what-is-math
      @what-is-math ปีที่แล้ว

      Hi Hope this helps: class tt(Scene): def construct(self): ga = ParametricFunction(lambda t : [t,-np.sin(t) /1.5-1,0], t_range = [-PI,PI], color = BLUE) self.play(Create(ga)) gat = ParametricFunction(lambda t : [t+6/sqrt(9+ 2*np.cos(t)**2) ,-np.sin(t) /1.5 - 4* np.cos(t)/sqrt(9+ 2*np.cos(t)**2)-1, 0], t_range = [-PI,PI], color = BLUE) dot0 = Dot((1.1)*ga.point_from_proportion(0) - (0.1)*gat.point_from_proportion(0) , radius = 0) dot2 = Dot(gat.point_from_proportion(0), radius = 0) tt = Arrow(dot0.get_center() , dot2.get_center(), color= RED, stroke_width=6, max_stroke_width_to_length_ratio=10, max_tip_length_to_length_ratio=0.15) self.play(Create(dot0), Create(dot2), Create(tt)) self.wait() para = ValueTracker(0) dot0.add_updater( lambda x: x.set_x((1.1)*ga.point_from_proportion(para.get_value())[0] - (0.1)*gat.point_from_proportion(para.get_value())[0] )) dot2.add_updater( lambda x: x.set_x(gat.point_from_proportion(para.get_value())[0] )) dot0.add_updater( lambda x: x.set_y((1.1)*ga.point_from_proportion(para.get_value())[1] - (0.1)*gat.point_from_proportion(para.get_value())[1] )) dot2.add_updater( lambda x: x.set_y(gat.point_from_proportion(para.get_value())[1] )) tt.add_updater( lambda x: x.become(Arrow( dot0.get_center(), dot2.get_center(), color= RED, stroke_width=6, max_stroke_width_to_length_ratio=10, max_tip_length_to_length_ratio=0.15))) self.play(para.animate.set_value(0.9), run_time = 10) self.wait()

  • @Ganerrr
    @Ganerrr ปีที่แล้ว

    This channel is super underrated, keep it up!

  • @petterlarsson7257
    @petterlarsson7257 ปีที่แล้ว

    I understood 28.75640274627467015562091% of what you said but I still enjoyed it

  • @awwab1094
    @awwab1094 ปีที่แล้ว

    I really appreciate you thanks 🌹

  • @agiri891
    @agiri891 ปีที่แล้ว

    you are seriously underrated

  • @dylanparker130
    @dylanparker130 ปีที่แล้ว

    Enjoyed this - thank you for making it.

  • @vigneshwarankannan4999
    @vigneshwarankannan4999 ปีที่แล้ว

    I hope you post a complete course on differential geometry

  • @vigneshwarankannan4999
    @vigneshwarankannan4999 ปีที่แล้ว

    Good work dude keep going..