Eigenvectors and eigenvalues | Chapter 14, Essence of linear algebra

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  • čas přidán 14. 09. 2016
  • A visual understanding of eigenvectors, eigenvalues, and the usefulness of an eigenbasis.
    Help fund future projects: / 3blue1brown
    An equally valuable form of support is to simply share some of the videos.
    Home page: www.3blue1brown.com
    Full series: 3b1b.co/eola
    Future series like this are funded by the community, through Patreon, where supporters get early access as the series is being produced.
    3b1b.co/support
    A solution to the puzzle at the end:
    www.dropbox.com/s/86yddvprfua...
    Typo: At 12:27, "more that a line full" should be "more than a line full".
    Thanks to these viewers for their contributions to translations
    Hebrew: Omer Tuchfeld
    ------------------
    3blue1brown is a channel about animating math, in all senses of the word animate.
    Various social media stuffs:
    Website: www.3blue1brown.com
    Twitter: / 3blue1brown
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Komentáře • 3,2K

  • @Thien--Nguyen
    @Thien--Nguyen Před 6 lety +6692

    We are probably the first generation ever to witness eigenvectors and eigenvalues and linear transformation animated, in motion as nicely and as accurately as this.
    We are very lucky to be in a time of incredible technologies and incredible people like 3B1B Grant here. Thank you!

    • @rosszhu1660
      @rosszhu1660 Před 4 lety +116

      Yes, indeed. You know during my time in university, nothing could help except your imagination, and you must verify any single piece of hypothesis with pen and paper.

    • @don9526
      @don9526 Před 4 lety +27

      Yes your generation is very spoiled.

    • @klam77
      @klam77 Před 4 lety +29

      True! When i went to school.....NEVER explained like this!

    • @henokgebeyehu1507
      @henokgebeyehu1507 Před 4 lety +34

      When I took linear algebra, I was not able to comprehend exactly what the eigen value and eigen vector represented. I just memorized the formulas. We truly live in an exceptional time. (I didn't take advantage of youtube as a resource for learning until recently)

    • @vannilesoep
      @vannilesoep Před 4 lety +197

      @@don9526 This generation isn't spoiled, it just has the unique opportunity to gain 𝘪𝘯𝘴𝘪𝘨𝘩𝘵 in these mathematical topics, instead of just learning a trick. And this insight could enable a much deeper understanding of mathematics or other topics, which could in turn spark new ideas or gaining more knowledge. Your comment implies a somewhat negative attitude towards this generation, we could also flip this reasoning around, saying "Your generation consisted of learning monkeys new tricks, the current generation consists of reaching insight and understanding", but lets not do that :)

  • @RealEngineering
    @RealEngineering Před 7 lety +6132

    I wish I had this in college. I struggled with this subject so much

    • @3blue1brown
      @3blue1brown  Před 7 lety +1355

      Thanks! Hopefully, current college students find it helpful. By the way, just watched your transistor video and loved it!

    • @RealEngineering
      @RealEngineering Před 7 lety +592

      They definitely will and thank you!

    • @pabilbadoespecial
      @pabilbadoespecial Před 7 lety +23

      Hey, glad to also see you here, love your videos!!!!

    • @JohnCLiberte
      @JohnCLiberte Před 7 lety +22

      CGP grey should also visit. Actually this 3b1b voice sounds like greys ..

    • @bryanjordan1263
      @bryanjordan1263 Před 6 lety +87

      I follow both your channels religiously (I'm an electrical engineering/neuroscience student in Sydney) and just floating the suggestion that if you two did a 3Blue1Brown X Real Engineering series exploring the physics involved in aeronautical/aerospace applications (wouldn't hurt looking into other engineering domains (eg. electrical lol) and examining other spaces of mathematics such as complex numbers) - you would be true MVPs of CZcams/academia (pretty sure they're considered equivalent).

  • @madelinescyphers5413
    @madelinescyphers5413 Před 2 lety +1765

    After having a degree in math, and working on my master's in optimzation, after audibly went "ohhh" when he first explained what eigen vectors and values were. Like, I finally get it. It's more than just some abstract thing that I need and use. These videos are golden.

    • @3blue1brown
      @3blue1brown  Před 2 lety +293

      Thanks so much!

    • @Milark
      @Milark Před rokem +44

      @@3blue1brown changing lives dude!

    • @wesm6747
      @wesm6747 Před rokem +26

      I just got my degree in Computer Engineering, and I'm working on my masters in Computer Engineering. Same thing here. I finally get it :,) These vids are amazing

    • @yaacheese8643
      @yaacheese8643 Před rokem +3

      @@wesm6747 Where do you use Eigenvectors and Eigenvalues in Computer Engineering if you don't mind me asking?

    • @wesm6747
      @wesm6747 Před rokem +7

      @@yaacheese8643 I've used it in a few Electrical Engineering classes. They've been more prominent in a scientific computing class I took in grad school. I think they also come up in comp graphics.

  • @VainCape
    @VainCape Před 3 lety +1145

    you deserve the nobel prize in maths for making math accessible like this to millions of students

    • @douglasespindola5185
      @douglasespindola5185 Před 2 lety +76

      Since that there is no math nobel prize, a Fields Medal should do the work. And yes, Mr. Grant deserves it!

    • @michaellai5549
      @michaellai5549 Před rokem +4

      Totally agree

    • @faizanpathan8645
      @faizanpathan8645 Před 9 měsíci

      hi, I still have a doubt at 10:34 it shows some non zero vector when squishes to one dimension it becomes 0 .
      But I have a doubt that it should be reversed according to matrix multiplication that in one dimension we have to find some non zero vector that becomes 0 according to our first basis vector that is [1,0] and [0,1]

    • @nalat1suket4nk0
      @nalat1suket4nk0 Před 8 měsíci +1

      there isn't a nobel prize in math

  • @chadmaster6936
    @chadmaster6936 Před 4 lety +5251

    "I wont teach you how to compute them" - Proceeds to teach us how to compute them better than any textbook or professor ever could

    • @gracialonignasiver6302
      @gracialonignasiver6302 Před 3 lety +364

      His explanation on why it's computed the way it is completely blew my mind. For nearly 4 years now I could compute Eigenvectors and I never understood why I was doing what I was doing.
      I seriously had to pause his video, get up out of my chair and pace around my room to let it sink in. Absolutely amazing.

    • @chadmaster6936
      @chadmaster6936 Před 3 lety +37

      @@gracialonignasiver6302 I only ever heard of eigenvectors.. never learned them (I was in hs when I first watched this) and I did the same thing where I stood up and was like "what did I just watch"

    • @paulbarton4395
      @paulbarton4395 Před 3 lety +46

      It can get pretty involved, his example was a 2 x 2 'upper triangular' matrix, which is why it turned out nice...but a 6 x 6 matrix thats not upper triangular will require some work, like Gaussian elimination, followed by finding the zeros of a 6th degree polynomial. Thats what computers are for tho

    • @erilgaz
      @erilgaz Před 3 lety +106

      @@paulbarton4395 but a 6 x 6 matrix that's not upper triangular will require some work, like painstakingly typing 36 numbers into wolframalpha and pressing enter.

    • @Manik481
      @Manik481 Před 3 lety

      @@gracialonignasiver6302 same here :)

  • @thenumber1723
    @thenumber1723 Před 4 lety +1196

    This person is the single most influential, and the only person around, in my life who made me understand the concept of Eigenvalues and Eigenvectors and their essence.
    God bless people like Grant who made themselves available (through online channels) to individuals who don't have such teachers, with positive influence, in their life to explain such complicated topics with fine clarity and simplicity :)

  • @zhuolovesmath7483
    @zhuolovesmath7483 Před 2 lety +258

    It's so lucky that this series is already complete when I'm studying linear algebra

    • @faizanpathan8645
      @faizanpathan8645 Před 9 měsíci

      hi, I still have a doubt at 10:34 it shows some non zero vector when squishes to one dimension it becomes 0 .
      But I have a doubt that it should be reversed according to matrix multiplication that in one dimension we have to find some non zero vector that becomes 0 according to our first basis vector that is [1,0] and [0,1]

    • @jhonnystiven
      @jhonnystiven Před 9 měsíci

      ​@@faizanpathan8645to find that vector you don't do it with an inverse matrix since matrices with a determinant of zero cannot be inversed. This series of videos explains this in the chapter about linear systems of equations. Because our vector equals to zero when multiplied by our matrix, what we need to find lies in the null space, which you can find using row echelon form and solving the linear system of equations from there. Look for explanations on calculating the null space on videos from other channels, like Khan academy.

    • @floatoss
      @floatoss Před 8 měsíci

      ​@@faizanpathan8645could you be more specific? Grant is basically saying that, if you calculate "what vectors, when pumped through this matrix (A - {lambda}*I), land to the zero vector", they are essentially your Eigen Vectors for the matrix 'transform 'A'.
      You are needed to calculate "what vectors are going to land to the zero vector when you pump through that matrix".

    • @faizanpathan8645
      @faizanpathan8645 Před 8 měsíci

      @@floatoss thnx , now I got it

    • @notrhythm
      @notrhythm Před 5 měsíci

      yeah

  • @michaelkotthaus7120
    @michaelkotthaus7120 Před 3 lety +395

    This is really good explained and the animations are delightful. For the viewers without any knowledge of the German language, it may be interesting, that "eigen" can be translated to "own" or "itself". So, an eigenvector is an "itself-vector".

    • @zinzin7075
      @zinzin7075 Před 2 lety +5

      Thanks!

    • @drizer4real
      @drizer4real Před 2 lety +10

      Same in Dutch

    • @pedrolinscosta
      @pedrolinscosta Před rokem +24

      In brazilian portuguese, we call them "autovalores e autovetores", which would sth like own-values and own-vectors, respectively...
      😊

    • @wiiznokes2237
      @wiiznokes2237 Před rokem +12

      In french is "vecteur propre"

    • @TheHitchhiker
      @TheHitchhiker Před rokem +34

      Of course english is the only language that leaves it in german.

  • @Robert-jy9jm
    @Robert-jy9jm Před 6 lety +829

    What kind of monster would downvote this masterpiece? This may very well be one of the best series ever made.

    • @MrCmon113
      @MrCmon113 Před 6 lety +7

      Robert
      What are you talking about?
      The votes are overwhelmingly positive.

    • @alexander-jl6cs
      @alexander-jl6cs Před 5 lety +41

      Ssshh!
      It's people from Australia and New Zealand.

    • @Chrysaries
      @Chrysaries Před 5 lety +69

      @@alexander-jl6cs Oh yeah, their votes scale with an eigenvalue of -1

    • @laurv8370
      @laurv8370 Před 4 lety +9

      indeed one must be a complete moron to downvote this video... I bet some frustrated math teachers are in that list (former math teacher myself)

    • @steves1015
      @steves1015 Před 4 lety +2

      Probably those who say “i hate maths”... ;)

  • @alyoco1156
    @alyoco1156 Před 4 lety +1801

    why am i crying watching these videos. They are so logical that i feel emotional now

    • @howardOKC
      @howardOKC Před 4 lety +51

      I am crying too! I am in tears!!! I love math and love great math learning materials. I just love it!!!!

    • @chunlangong2214
      @chunlangong2214 Před 4 lety +7

      @@howardOKC me too

    • @azra8366
      @azra8366 Před 4 lety +8

      me too, such a good explanation I wish my prof is that good...

    • @jerrys_milk
      @jerrys_milk Před 4 lety +18

      I'm not crying, but my heart is beating like crazy lol

    • @82Muntasir
      @82Muntasir Před 4 lety +2

      Me too dude

  • @Cena199205
    @Cena199205 Před rokem +261

    I cannot thank you enough for this awesome series. Like others, I have a master degree and I still don't fully understand some of these basic concepts! Even after 6 years of publishing this series, it is still the best series explaining linear algebra.

  • @Emoechaiti
    @Emoechaiti Před 2 lety +25

    0:16 The beauty of music lies on how we perceive it (decoding process of sound in our brains). But the beauty of mathematics, even though everyone has an inbuilt intuition about it just like music, still people don't understand because they can't relate the numbers, symbols, methods, formulas, graphs, and other mathematical entities with the reality (existence). While Mathematics is all about reality.
    How frustrated would someone be if they can't relate the written musical notes with their respective sounds !!!
    The way you teach is honestly the best way to understand mathematics. Your hardwork in the field of your interest is clearly visible in the beauty of your teaching.
    Thank you sir 🙏
    And keep inspiring us

  • @tomtom9509
    @tomtom9509 Před 7 lety +565

    I understood more about Eigenvalues and Eigenvectors in 15 min. than I did in two years of math undergraduate course. Thanks a lot. and great animation work too!
    It was the same for derivatives and integrals. I did great marks in high school in physics and maths but I truly didn't get why derivatives and integrals were working for physics. For me it was magic. I learned the formula and applied them, but it was just black box techniques. It is only at university that a friend of mine in 10 min. explained their meaning to me and everything became crystal clear. Those 10 min. simply changed my life.
    I think teachers should be every attentive to this.Take some time to teach the meaning, the big picture and only then get into the nitty gritty details.

    • @kevinbyrne4538
      @kevinbyrne4538 Před 7 lety +40

      There's a saying: "Those who can, do ; those who can't, teach." However, teaching is also an art and a skill. It was often a shock to me at university that accomplished scientists were often bad teachers.

    • @StefSubZero270
      @StefSubZero270 Před 7 lety +4

      You are right! I just completely finished my geometry (linear algebra) course at Physics department and i have a tonshit of doubts about it and i have the exam in 1 months. I'm struggling do study it and solving exercises (because i also have other courses i have to study to obviously), but finding these channel helped me A LOT to understand what was my professor talking about :D

    • @CombraStudios
      @CombraStudios Před 7 lety +2

      15 min? are you watching math on 1.25 speed?

    • @mohabmetwally5749
      @mohabmetwally5749 Před 7 lety +4

      sometimes i do in 2X depending on motivation, attention, professor age :)

    • @niemandniemand2178
      @niemandniemand2178 Před 5 lety

      dumbass

  • @SantiagoRodriguez-bx6jy
    @SantiagoRodriguez-bx6jy Před 6 lety +1434

    you deserve heaven more than anyone

    • @gergananikolovagery5058
      @gergananikolovagery5058 Před 5 lety +6

      oh, man XD yes!
      you're so right

    • @eoe196
      @eoe196 Před 5 lety +13

      As it is written, There is none righteous, no, not one:

    • @vaydada
      @vaydada Před 5 lety +1

      Exactly :))))

    • @rj-nj3uk
      @rj-nj3uk Před 4 lety +3

      But he don't want to die.

    • @DanielInfrangible
      @DanielInfrangible Před 4 lety +3

      I'm going to solve quantum computing just so that I can create a real heaven for this majestic animal's brain-soul to be uploaded to after he dies.

  • @meghmalharmanekar1211
    @meghmalharmanekar1211 Před 3 lety +64

    First time in my life I got the insight of what the "diagonalization of matrix" actually means. Heavily indebted to your efforts! Can't express my gratitude.

  • @Buckybarnesfan22
    @Buckybarnesfan22 Před rokem +41

    Came here to revise Eigenvectors and Eigenvalues and ended up watching the entire Linear Algebra series. You're a true legend. Thank you for the clear teaching!

    • @guggi_
      @guggi_ Před 7 měsíci

      Same here

  • @ProfessorEisenoxid
    @ProfessorEisenoxid Před 7 lety +78

    I cant name one video producer who has such an enormous positive feedback and with viewers who are so fascinated by the content!

    • @3blue1brown
      @3blue1brown  Před 7 lety +55

      You commenters are the freaking best. Usually, CZcams comments can be such a dark hole, but every video I've been uplifted and pumped to make more.

    • @ProfessorEisenoxid
      @ProfessorEisenoxid Před 7 lety +13

      +3Blue1Brown Therefore, not only your explanations are higly intuitive yout animations fit and are beautiful, a fine piece of video-art!
      I am looking forward to every video!

  • @Hivlik
    @Hivlik Před 5 lety +1487

    i love when the pi students get mad

    • @enormousmaggot
      @enormousmaggot Před 3 lety +72

      They always chill back out in the end

    • @udaykadam5455
      @udaykadam5455 Před 3 lety +24

      It bothers me somehow when they show anger instead gratitude

    • @EvilMAiq
      @EvilMAiq Před 3 lety +32

      @@udaykadam5455 I think it's more frustration than anger.

    • @danialdunson
      @danialdunson Před 3 lety +2

      @@EvilMAiq yeah its more of a table flip react

    • @alinapostol2230
      @alinapostol2230 Před 3 lety +1

      rofl =))

  • @marianseidl662
    @marianseidl662 Před 3 lety +70

    I rarely comment on videos but I just have to say this one thing. You deserve so much respect for what you do and how you do it! In all my years of school and university, I never came across anyone who could explain and visualize topics the way you do it. Our world has all these great scientists who discovered unimaginalbe things, but this wouldnt mean anything if we didnt have people like you!

  • @techiesithastobetechies.8531

    I have sunk in more than 7000 hours playing video games throughout the last decade, these videos are more ENTERTAINING than all of those video games.
    These videos are the most FUN I have had in a FULL DECADE.
    The amount of "aha!" moments is so satisfying!
    Feels like I could have invented Linear Algebra all by myself now!

  • @HAAH999
    @HAAH999 Před 7 lety +461

    I can't believe that I've spent all these years at school and university without knowing all these things about linear algebra. Specially after this video and knowing the power of eigen basis. Thank you so much for this wonderful series it's actually helping me in my computer vision course. I would be very very grateful if you put another series about Fourier series and Fourier transform

    • @NZwaal-tg8ur
      @NZwaal-tg8ur Před 7 lety +11

      I second this request!

    • @grekogecko
      @grekogecko Před 6 lety +2

      I third it!

    • @lated2222
      @lated2222 Před 6 lety +5

      I'll 2^2 it!

    • @danwang4625
      @danwang4625 Před 6 lety

      5

    • @MsStefHipHop
      @MsStefHipHop Před 6 lety +2

      I (squareroot of 72)/(squareroot of 2) this message! Could you please post a series on Fourier series and Fourier Transform?

  • @marioalbanese9993
    @marioalbanese9993 Před 3 lety +274

    i've learned more in this 17 minuts than in hours passed at the polytechnic of milan, thank you

  • @animeshsinghal3405
    @animeshsinghal3405 Před 2 lety +26

    At 3:50, I paused the video and celebrated my excitement for 5 minutes. THIS MAKES SOOOO MUCH SENSE!! The build-up was worth it! Thank you :'")

  • @killianpinier5074
    @killianpinier5074 Před 3 dny +1

    Thank you so much for your incredibly rich content. Unlike most professors, you start by explaining the practical interpretation of a concept before translating it into theory. This approach is refreshing because many people are satisfied with just understanding the theory, but they often miss out on its physical meaning. This gap is why many struggle with physics: they learn the theory but don’t know how to apply it to the real world. But solving a problem requires working backward: you interpret the real world and apply it to the theory.

  • @robertbazzocchi5385
    @robertbazzocchi5385 Před 6 lety +510

    14:25
    *stops video*
    *plays video two weeks later*
    I see your point...

    • @zairaner1489
      @zairaner1489 Před 6 lety +8

      lol

    • @DarkFoxV
      @DarkFoxV Před 5 lety +7

      I see what you did there... actually no, try to explain it Dx

    • @mahmoudrateb7344
      @mahmoudrateb7344 Před 5 lety +4

      hhahahahhaa, smarter than to try

    • @xl000
      @xl000 Před 5 lety +2

      I will use your hi res profile picture for something.. Not sure what

    • @don9526
      @don9526 Před 4 lety +1

      U dont know how to use a calculator?

  • @FlareGunDebate
    @FlareGunDebate Před 4 lety +251

    My experience with math is: watch Khan, watch you, interpret painfully dry book. Thank you, sir.

    • @dankazmarek1259
      @dankazmarek1259 Před 3 lety +7

      so real...I feel the same, I am going for Computer Engineering and I know I have to feel the pain of translation and interpretation strike like a thorn in my butt

    • @FlareGunDebate
      @FlareGunDebate Před 3 lety +7

      ​@@dankazmarek1259​I've been building physics simulations. Most pages are self advertising in disguise as educational resource. That or hobbyists publishing their inner thoughts and muddled process. I hope to write some clear articles on the subject one day.

    • @FlareGunDebate
      @FlareGunDebate Před 3 lety +4

      @Dr Deuteron I've done the math. Khan Academy is good for working though that. This channel is good for the intuition and thought experiments.

    • @sukhmandersingh4306
      @sukhmandersingh4306 Před 2 lety +6

      Mit courseware is also very good.

  • @AntonKimS
    @AntonKimS Před 2 lety +12

    I could not understand eigenvectors and eigenvalues for 14 years. After watching (in utter amazement) all of your videos in just two days, I have finally understood these concepts! So grateful! Thank you!!!!!!

  • @ahmedayman8369
    @ahmedayman8369 Před 2 lety +7

    This...is breathtaking. Mesmerizing to look at these transformations. Dreamy to ponder what those lambdas do and what an eigenvector is. They come to life when I close my eyes now. A very sincere, appreciative and kind Thank You from a struggling student at the University of Hannover.

  • @car_pal
    @car_pal Před 6 lety +772

    this kind of math can only be explained clearly with visual examples and animations it's been more then a week since i started studying eigenvectors and never understood it. Now i'm 3:40 minutes in and i got it lol

    •  Před 6 lety +51

      some people spent years before this video, no worries, a week is a good time

    • @zenchiassassin283
      @zenchiassassin283 Před 5 lety +2

      Well me I don't study it yet but it's interesting

    • @niemandniemand2178
      @niemandniemand2178 Před 5 lety +3

      your just an dumbass

    • @soundninja99
      @soundninja99 Před 5 lety +18

      @@niemandniemand2178 Piss off. This is hard for a lot of people.

    • @squeakybunny2776
      @squeakybunny2776 Před 5 lety +17

      @@niemandniemand2178 said by the person writing 'your' instead of 'you're'

  • @noahmarshall4520
    @noahmarshall4520 Před 5 lety +575

    This series is literally worth more than the 400 I've paid to take linear algebra in uni.

    • @diegomastro5681
      @diegomastro5681 Před 5 lety +37

      Then donate

    • @soundninja99
      @soundninja99 Před 4 lety +60

      Currently taking linear algebra in uni (lin. alg. for engineer students, no the more proof oriented one for math students). This is a great supplement to lectures to truly understand the material, but it doesn't replace it. Super fucking grateful for this though. Grant makes maths more fun

    • @davibergamin5943
      @davibergamin5943 Před 3 lety

      Currently taking linear algebra in uni, even my teacher recommended this serie

    • @PJMM
      @PJMM Před 2 lety +9

      @@soundninja99 This, thank you!
      I read it so often that "this is so much more worth than university". But IMHO and personal experience, I believe I wouldn't grasp the entire concept in its depth just by CZcams videos, most of all not as complete and structured as taught in university (at least over here & it might be worth mentioning that it's free) and most of all I'd lack the learning environment created at this place. But you are also spot on about as supplement material, this is really invaluable. And I do still get where many people are coming from - 3b1b really does take the time to explain the fundamentals in a way it's often rushed past at university, leaving you behind with the feeling of "not really getting it"!
      So all in all, you put that into much better words than I could anyway. Much appreciated, really.

  • @jasonlewis5125
    @jasonlewis5125 Před 2 lety +2

    I feel like I’m gonna cry. The detailed visuals and pauses while explaining things show that you care about us understanding. I’ve never felt someone care so much about my understanding to pause like this. I know it’s just a CZcams video but thank you!

  • @gerardsagliocca6292
    @gerardsagliocca6292 Před rokem +2

    Listening to this video is the first time I actually understood what an eigen vector and eigen value really means because you gave the visual representation of that an igen vector, eigenvalue is doing on a x y plane.
    No textbook that I ever bought or borrowed at a library ever showed your graphical meaning. The authors went on and on about how to find them but never gave the student to he graphical dynamics involved to get that quick realization. Even MIT professor Strom I believe never showed any visual presentation, so nobody really understood what was going on in linear algebra and so linear remains a scary topic in mathematics for many students.
    So I am glad I happen to come across this inspiring video that wiped away all the fear and anxiety over a required course in most tech curriculums.
    How you figured out how to fix this awful situation is truly an amazing thing. You seem to have a gift of clarifying some reALLY NASTY situations in mathematics.
    Kudos to you.
    And while I am at it, you also clarified quickly confusion in another topic in mathematics that electrical curriculums discuss but never really clarify what it really means and that is ...Convolution !
    Today, in 2023, students are fortunate to have great videos on CZcams so they can. Get away from technical books that never clearly explain anything, except having many problems at the end of a chapter which many students can't do because textbooks are a 2 dimensional format and most times one needs a 3 dimensional tool to explain the graphical interpretation so students can quickly understand the topic being discussed. So I am glad textbooks are being replaced by more better tools to convey the meaning to a student trying to learn the math and the concepts being introduced by a teacher.
    ,

  • @swinfwar
    @swinfwar Před 6 lety +67

    Every student in introductory quantum mechanics needs to watch this video. These concepts are extremely important to QM and it really clears up the importance of the eigenstates of operators. Thank you for the great explanation!

  • @biznock09
    @biznock09 Před 7 lety +124

    It's amazing. I fell in love with linear algebra because of its computational power and knew there was intuition buried in the numbers. I frequently, if not always had my questioned that I could only express at the time using "visual vocabulary" ignored or interpreted as interruptive. This information should be mainstream and the preface to every topic explained in text books. I challenge you, if you are not already planning on it, to continue this model for other areas in math. My desire to learn math was sparked not for an affinity to be able to crunch numbers in my head, but rather my fascination with patterns and visualization. Actually, by any standard I'm average at best with mental math, but achieve above average results in mathematics. Calculating is a non-intuitive chore where as visualization exercises tap into, what I believe is, a core skill that all humans have. That being the case, this model has the potential to make math literacy far more accessible.

    • @error.418
      @error.418 Před 7 lety +18

      I would argue that those who do the best in math competitions use visualization techniques. Visualizing is an important part of math literacy and is unfortunately not widely taught with any quality.

    • @arsenalfanatic0971
      @arsenalfanatic0971 Před 4 lety +2

      @@error.418 It feels like the people who are better at math are better at visualization. It can be taught but not many bother to teach it so i think too many people are doomed to thinking they're inherently bad at math

    • @error.418
      @error.418 Před 4 lety +1

      @@arsenalfanatic0971 yeah :(

    • @Hexanitrobenzene
      @Hexanitrobenzene Před 2 lety +2

      Well, to counter this point, many scientists say that the power of mathematics lies in its ability to help solve problems which are too difficult to visualise and/or where intuitions (including visual) break. That being said, it's always good to have a visual intuition where it's possible.

  • @lucasnebelung5430
    @lucasnebelung5430 Před 7 měsíci +2

    I never really thought of Maths of something fun, but your videos make it so easy and most importantly fun to understand all the concepts and how they are actually closely related to each other. I'm so thankful for your videos and really enjoyed watching all of this and your other series on Analysis etc. You're by far the best math teacher and in my humble opinion a million times better than anyone else on YT. Keep up the great work. Thank you so much!

  • @winterturtle1596
    @winterturtle1596 Před 3 lety +2

    Sometimes in my senior level undergraduate numerical methods class I get confused, and I keep coming back to this video. It's such a good way of understanding these concepts. To me, the most useful parts of this are definitely the showing mathematically why the formula Av=lambda*v comes from and how it relates to the method of finding eigenvalues, as well as the change of basis formula in relationship to achieving an eigenbasis. Interestingly, as we learned in this class, you can solve for the eigenvectors by looking for a matrix such that when used as a change of basis it results in a diagonal matrix for any matrix A. Thanks to your video, statements like this aren't astounding, or something I would need to memorize, but rather something that is obvious, and intuitive. Thank you again for these highly educational videos, you are doing a great service to the world.

  • @tokkia1384
    @tokkia1384 Před 4 lety +228

    “Squishification” 😂 ❤️ made my day

    • @hemrajpandeya81
      @hemrajpandeya81 Před 4 lety +1

      me to

    • @Amb3rjack
      @Amb3rjack Před měsícem

      Yes! That word could well be the key to life, the universe and everything. For me it really is a genius piece of fully understandable made up language that exemplifies the genius of this gentleman's concise but very easy going and extremely watchable teaching methods. Just magnificent!

  • @KaraHinamori
    @KaraHinamori Před 4 lety +27

    I feel like part of the reason why your videos work so well is that you give the listener time to pause and think. Even the small pauses after every sentence gives me time to absorb the information, not to mention it's really calming

  • @ashutoshpatidar3288
    @ashutoshpatidar3288 Před 4 měsíci +2

    The Level of Clarity in the words this man spit is absolutely feels insanely Divine!!! Omg is it even possible for someone to be that clearly understandable...he is definitely a miraculous teacher i had ever seen in my life!

  • @kjekelle96
    @kjekelle96 Před rokem +59

    0:00 intro
    1:20 effect of linear transformations on spans
    2:59 examples of eigenvectors
    4:04 applications
    5:15 goal of this video
    5:26 how to find eigenvectors and eigenvalues
    7:35 geometric meaning of the formula
    9:28 revisiting an example
    10:46 are there always eigenvectors?
    13:03 eigenbases
    16:28 puzzle and outtro

  • @patrickwienhoft7987
    @patrickwienhoft7987 Před 7 lety +75

    This was probably the biggest enlightening I experienced ever...

  • @charlesz88
    @charlesz88 Před 4 lety +84

    For anyone who is confused about the last exercise:
    1. Use NewTransform = inv(EV)*A*EV to get the diag matrix representing transformation A in eigenbasis system.
    2. Compute NewTransform = NewTransform^n
    3. Use to EV*NewTransform*inv(EV) convert back to the previous system.

    • @ompatel8091
      @ompatel8091 Před 4 lety +3

      Thank you! It was a bit confusing but your comment made it crystal clear.

    • @antonisskarlatos5202
      @antonisskarlatos5202 Před 4 lety +18

      Thank you too man, it was helpful !
      I am just adding some extra details in case anyone needs more help.
      We have a vector v and we want to apply to it k times the transformation A: A^k * v
      We know that inv(EV) * A * EV = D, so by mutliplying from left with EV and from right with inv(EV) we take
      A = EV * D * inv(EV).
      Now lets try to take A^2 = EV * D * inv(EV) * EV * D * inv(EV) = EV * D^2 * inv(EV).
      Inductively this gives us that A^k = EV * D^k * inv(EV).
      So to calculate A^k, we can just in O(n) time to calculate D^k and just apply in the end the two other mutliplications.

    • @antonisskarlatos5202
      @antonisskarlatos5202 Před 4 lety +1

      @@MengLiu-bi9dz At inv(EV) * A * EV = D, we are interested to create the diagonal matrix D.
      The idea here is that if someone gives us the i-hat = [1 0]^T or the j-hat = [0 1]^T, we would like the transformation D to just stretch them. So let's say someone is giving us the i-hat = [1 0]^T, then through the EV we would convert it to one of the eigenvectors. After we would apply the A and we would get a scalar of our eigenvector, and finally with inv(EV) we would go back, having a scalar of i-hat (remember that the transformations are linear and scalars stay on the same span). So after the three transformations our i-hat, will be converted to something like [k 0]^T, where k a real number.
      This means that: (inv(EV) * A * EV) * ([1 0]^T) = [k 0]^T
      so we can easily conclude that the first column of the matrix D is [k 0].
      Finally, applying the same thought with j-hat we can prove that D is diagonal indeed.
      To say the truth, this is the only intuition I do have. My understanding is that we are just trying to get a diagonal matrix. When we manage to get it, the calculations are easy, so with simple algebra we take a close form of A which depends on D and because D is easy to manipulate, A becomes easy as well.
      I would love to hear other views on it from other people who are more familiar with linear algebra !

    • @alphonseraynaud976
      @alphonseraynaud976 Před 3 lety

      but how do you compute the inverse?

    • @forthrightgambitia1032
      @forthrightgambitia1032 Před 3 lety +1

      I found the chain of logic easier if you convert the basis vectors into the equivalent [1+sqrt(5)/2 1] and [1+sqrt(5)/2 2], then the eigen values pop out.

  • @LMaudy
    @LMaudy Před rokem +14

    I just had this determinant class, you explained perfect what eigenvektor and value is as well as why is det(A-λI) even used, thank you for saving me hours of my life

  • @rotemperi-glass4825
    @rotemperi-glass4825 Před rokem +11

    Thanks so much! your videos not only make my view of the world much more interesting and deep, they are also the most fun content I can find on CZcams.

  • @baguettegott3409
    @baguettegott3409 Před 4 lety +16

    This series is so neat. I've watched it a while ago, before learning any linear algebra beyond the absolute basics, and I enjoyed it well enough - although I didn't take that much away from it. Now that I'm actually hearing linear algebra lectures, I regularly come back to particular videos when the topic comes up, just to build up some more familiarity and visual intuition, and I can hardly express how helpful and rewarding that is :)

  • @andresmassigoge8600
    @andresmassigoge8600 Před 7 lety +61

    From the thousands of Eigenvideos on youtube, this is truly an Essential one.

    • @guigagude
      @guigagude Před 5 lety +4

      Andres Massigoge It's the eingenbasis, for sure

  • @mark7166
    @mark7166 Před 2 lety +2

    Linear algebra was always one of my favorite subjects back in my engineering education days. I'm relearning it as part of an effort to train myself in machine learning, and this series has reminded me of exactly why. It's an astoundingly beautiful topic.

  • @jessicathelen7810
    @jessicathelen7810 Před 2 lety +1

    I can't wait to watch the rest of these! I am currently in LA again as a refresh and my instructor did not teach it well the first time and unfortunately am in the same boat again! I literally got up at 3 1/2 minutes and just paced around b/c it blew my mind w/ understanding - FINALLY! Halfway through, I paused and shared it with my college class who is also struggling! This one video helped me so much already seriously - thank you!!!!!!!!!!

  • @dn9255
    @dn9255 Před 4 lety +33

    This video gave me so many "AHA!" moments and cements all the information you've taught in former videos of the series. Thank you so much!

  • @neerajaggarwal4689
    @neerajaggarwal4689 Před 4 lety +452

    Just imagine how much difficult it is to teach topics like these on a board. You can blame your teachers but just imagine.

    • @ellyvatedaf
      @ellyvatedaf Před 4 lety +49

      Well, thats why its important for students to sit down with their own thoughts and time to visualise whats happening by themselves

    • @MilosMilosavljevic1
      @MilosMilosavljevic1 Před 3 lety +97

      Why would they have to use a board though? Any decent math professor should be able to use something like Mathematica or Geogebra to produce a decent animation to suplement a lecture.
      So the problem is not in the difficulty of how, it is almost certainly in the lack of why.
      There simply is no incentive to be a great lecturer when in most universities you are only judged by your research. You do your research well enough and you can be the worst lecturer ever, your job is perfectly safe.
      So, most professors will look at making an effort to produce great learning materials as a waste of time, if they focus too much on lecturing and lag behind in research, they might easily lose their job to someone that outproduces them in research.

    • @user-jh3kz7dp2z
      @user-jh3kz7dp2z Před 3 lety +4

      @Arjun lalwani GeoGebra, it's the name of a software, you can't just casually rescript it

    • @umadbroyo2388
      @umadbroyo2388 Před 3 lety +32

      @@MilosMilosavljevic1 Spoken like a true student from a first world country!

    • @PaulSmith-pr7pv
      @PaulSmith-pr7pv Před 3 lety +1

      @@MilosMilosavljevic1 academia is stupid

  • @stanpreschlack6196
    @stanpreschlack6196 Před rokem +1

    i cannot believe how you explain these concepts so well never in a million years did i think i could understand linear algebra but watching your videos all of the concepts just 'click' and it makes it so easy to learn more about the topic because you offer such an effective framework of understanding.

  • @physlers9705
    @physlers9705 Před rokem +1

    No word can do justice in praise of your great knowledge neither to the efforts you put in to make these animated videos. You are just incredible. The world is in dire need of teachers like you.

  • @drdcs15
    @drdcs15 Před 7 lety +7

    I look forward to these every day, hoping one will come out. I've tried so hard on my own to understand all of this. It's like I have a ton of almost finished puzzles floating around in my head and every video I watch a piece clinks into place and the one of the pictures is revealed. Absolutely incredible. Thank you

  • @saitaro
    @saitaro Před 7 lety +236

    I like the indignation of the little pi's animation :P

  • @sanchitapihu
    @sanchitapihu Před 2 lety +1

    I had never ever come across such a beautiful explanation of eigenvalues and eigenvectors. This is by far THE BEST explanation of the concept. The entire series is mind-blowing. Never saw matrices from such a perspective. Hats off!!!

  • @maartenkeus8627
    @maartenkeus8627 Před 3 lety +3

    In literally the first 10 seconds I have already gained a better understanding then uni could have evert taught me, you're an actual wizard and these visualizations are revolutionary
    Thank you

  • @Zeus.2459
    @Zeus.2459 Před 4 lety +73

    11:30 hit like a ton of bricks
    I paused the second I saw "i", and thought back to his video about euler's identity
    maths is goddamn beautiful

  • @evangelosstromatias4879
    @evangelosstromatias4879 Před 5 lety +128

    This guy is the Morgan Freeman of maths. Thank you!

  • @Oreoezi
    @Oreoezi Před rokem +21

    You just turned 1 hour of university in 17 minutes of things I actually understand. Thank you so much.

  • @bennet615
    @bennet615 Před rokem +2

    i have watched this videos over 30 times in past 6 years and yet everytime i find something new, and always come from trying to understand eigenvalues from adifferent point of view, maths is amazing

  • @guycollishaw1957
    @guycollishaw1957 Před 4 lety +390

    The moment I hear the word Eigen... my brain just decides to work at 10% its usual capacity.

    • @enormousmaggot
      @enormousmaggot Před 3 lety +29

      Once you finish this video, go check the German too -- eigen literally just means 'one's own'

    • @CuteLittleHen
      @CuteLittleHen Před 3 lety +7

      Think about Eigenvalues as being a self value. :)
      For example, if the vector spaces has a self value of 0, this means the kernel is not made of only the 0 vector.

    • @khatharrmalkavian3306
      @khatharrmalkavian3306 Před 3 lety +2

      I feel that way about sigma notation.

    • @tanmaydeshpande
      @tanmaydeshpande Před 3 lety +2

      The moment I heard the word Eigen, my mind went straight to the Endgame scene where Tony discovers Time Travel

    • @alexandertownsend3291
      @alexandertownsend3291 Před 2 lety

      @@khatharrmalkavian3306 sigma like for standard deviations or do you mean the one for sums? I can explain whichever one you want me to.

  • @ophello
    @ophello Před 7 lety +81

    The imaginary eigenvalues blew my mind. That's where euler's identity comes in!

    • @Alzeranox
      @Alzeranox Před 6 lety +37

      Funny enough, there is an vector which is going completely unchanged in that example. But it extends into three dimensions. If you go back and watch the example, imagine a line coming straight out of the origin towards yourself. That imaginary line is the eigan vector.

    • @AuroraNora3
      @AuroraNora3 Před 6 lety

      Timothy
      :0

    • @Raikaska
      @Raikaska Před 6 lety +2

      Timothy but arent we sitting in 2 dimentions? We could also argue that E5, E58 remain uncanged, but they arent in the original space? I guess its related to cross product

    • @zokalyx
      @zokalyx Před 6 lety

      we are in 2D
      going back between dimensions is not so simple.
      what you are saying would make our vectors something like and , etc. (with z = 0). That would be 3D, but the vectors seen in screen were all represented by 2-tuples, therefore they are 2D.

    • @BettyCastella
      @BettyCastella Před 5 lety +1

      @@Alzeranox which corresponds to the imaginary axis!!!

  • @germanbuenolozano3941
    @germanbuenolozano3941 Před 2 lety +6

    Good eavning, I am german, an engineer on formation, I feel the obligation of thanking you for this video, I am going to pass my test thanks to you

  • @n00bowser
    @n00bowser Před 3 lety +1

    This is probably one of my favourite 3B1B -videos. All the physics using eigenvalues equations feels so much more intuitive now!

  • @TheJupiteL
    @TheJupiteL Před 7 lety +225

    I'd probably ace all my math classes if the lecturers actually explained what the heck we're doing instead of writing formulas first thing they're in the class.

    • @whitewalker608
      @whitewalker608 Před 6 lety +21

      Lol seems like teachers all over the world do this.

    • @kansshha5301
      @kansshha5301 Před 5 lety +5

      Same problem

    • @UserAnonymus1995
      @UserAnonymus1995 Před 5 lety +22

      Same in Russia. Feels like they write formulas as soon as they come in just to intimidate the students and assert dominance lmao. I also had teachers who told everyone off for asking questions, which made it even harder to understand anything.

    • @eriangelino7800
      @eriangelino7800 Před 4 lety +4

      Yes, they prepare you for the exams and once you pass the exam the formulas evaporate.

  • @motaaaa
    @motaaaa Před 7 lety +37

    Astounding, I'm going to study this subject next semester and it's wonderful how I can already grasp it's intuition quite well, you sir deserve some 1 billion subscribers

  • @Hevever
    @Hevever Před 2 lety +1

    Did an undergraduate degree in mathematics and yet this is the first time I have thought about these concepts in this intuitive way..! could do the sums but never understood what was going on behind the scenes. wish I had had these videos during my degree but glad to see them now!! thanks so much

  • @user-tp2wz1gq4z
    @user-tp2wz1gq4z Před měsícem

    Thank you so much for creating these videos! As a university student, I often find textbook materials not enough for visualizing linear algebra concepts. Your visualizations bring these abstract ideas to life, making them much easier to understand. Last week, even my professor put your video during our office hours session and advised to watch all of them during summer. Your efforts are truly appreciated-keep up the great work!

  • @alejandrot7976
    @alejandrot7976 Před 4 lety +3

    Don't have words to thank the awesome work you are doing... You are lifesavers for a new generation of mathematicians, scientists, engineers, and in general, for people like me, trying to learn something everyday. THIS, is the bright side of CZcams. Masterpiece!

  • @zairaner1489
    @zairaner1489 Před 7 lety +20

    What? The shock! I didn't expect that so quickly! I'm not prepared!!

    • @alvarol.martinez5230
      @alvarol.martinez5230 Před 7 lety +3

      I just wish he is saving material for an Essence of linear algebra II

  • @panayiotismichaelides3148

    Super intuitive and well explained, amazing video!

  • @the_vine_queen
    @the_vine_queen Před rokem

    I've been doing eigenvalues/vectors in differential equations and linear algebra for a while now, and i always knew *how* to do them, but not *why* they did what they did. This totally changed my perspective on LinAlg, and it's so much more straightforward to do it now! Thank you!!!

  • @altolegato2493
    @altolegato2493 Před 7 lety +20

    I have to point out a nice trick about the eigen stuff. If during exam, you obtained all eigen values for a matrix in previous questions, and the next one requires the DET of the same Matrix, Please note that The DET of that Matrix=Product of all eigen values. It saves your time during exam.

    • @zairaner1489
      @zairaner1489 Před 7 lety

      There actually is another way which just needs you to have calculated det(A-lamda*Id), the determinant will be the constant part of the resulting polynomial

  • @nicolevelazco2098
    @nicolevelazco2098 Před 4 lety +3

    Bravo! The best animations I've ever seen. It's impressive how you explained eigenvectors in less than 20 min. Thank you so much for helping me understand

  • @suvarnadhiraj
    @suvarnadhiraj Před 3 lety +2

    The content is so good that it needs to be seen more than once to understand the deeper meaning of the concepts.
    This series needs to be binged several times at least for me :)

  • @utkarshshrivastava4382

    Beautiful Video man, I watched the whole series for this video, and it was one of the most clarifying experience I have had for linear algebra. I have been asking everyone, seniors, friends, professors, google, everyone, what do eigenvectors and eigenvalues mean, and this is the first time after 6 years, literally the first time that I have finally understood the depth and meaning of these things. It was a mind = blown moment when I watched it after 14 previous lectures in this series. Thank you for making this whole series, and kudos on your work. Your style of teaching, ease of explaining, clarity of concepts, beauty of animation and the simplicity of music and videos is extremely commendable. I genuinely think that this whole series should be taught as a part of linear algebra courses across all colleges around the world. The finest level of clarification students will get will help them in every aspect of their studies, research, way of thinking, everything. Again, thank you for making this series, absolutely loved it, and I at least will be referring to your channel for any clarification/assistance in topics related to mathematics. Good Job and Good Luck!!!

  • @wiaschtlsiara9516
    @wiaschtlsiara9516 Před 5 lety +4

    Astonishing animations, perfect explanations, high quality audio. Nothing my university has.
    Thank you very much.

  • @SmileyMPV
    @SmileyMPV Před 7 lety +10

    That puzzle at the end is basically a very complicated way to get the fibonacci formula...
    AND I LOVE IT

  • @jasonavina8135
    @jasonavina8135 Před 2 lety

    using this right now for my linear algebra final. These videos are a HUGE help understanding these topics conceptually. We learned how to calculate these things mechanically, but the visualization and ideas were what i needed to understand better and this is really really great at that. Thankyou.

  • @Fleato
    @Fleato Před 3 lety +2

    Man I have been following this page for years even before even thinking I’d go into engineering in my late 20’s and I always liked these videos at a distance not understanding any of the math but appreciating how satisfyingly these things worked. Now.... I need these videos to understand the horror of the difficulty of the math I know am actually doing.

  • @gustavopazrequejo6691
    @gustavopazrequejo6691 Před 5 lety +97

    OMG! I'm in 4th year of the degree physics and at the min 3:38 i started to cry

  • @clavisjanes3927
    @clavisjanes3927 Před 7 lety +11

    All of your videos are so thorough; truly amazing!

  • @lukachannel12
    @lukachannel12 Před 10 měsíci

    You explained this whole series so well and thoughtfully that you can go months without doing anything related to linear algebra and still have a clear, lifelong grasp on the most important aspects. It honestly beautiful what you have done.
    P.S. Your videos helped me tremendously to get a Masters in A.I. and deep learning. Thank you so much!!

  • @keggluneq
    @keggluneq Před 3 lety +2

    This series should be mandatory for intro to linear algebra courses. Grant is an incredible teacher and science communicator.

  • @marinarapp500
    @marinarapp500 Před 4 lety +12

    I have many mindblowing moments watching this series. Makes me like maths much more! Thank you!

  • @johnhumbug5199
    @johnhumbug5199 Před 7 lety +18

    lol says: i won't explain the computation in detail!
    But explains it by making the computation as intuitiv as possible.
    Thanks for this series...

  • @HiHi-iu8gf
    @HiHi-iu8gf Před 8 dny

    Never really had use for eigenthings, so I kinda glossed over this video the first time I came across it while going through the linear algebra playlist - but really fantastic to come back now that I *do* need to work with eigenvectors/values, and have this outstanding explanation. Amazing work as always! I don't think I'd ever have enjoyed (or been able to even do) math as much as I do without 3b1b videos

  • @gregoryneedsaname
    @gregoryneedsaname Před dnem

    Wow. It only took you 3 minutes to explain something that I couldn't understand for the past 23 years. Bravo!

  • @apanapane
    @apanapane Před 6 lety +3

    Thank you, thank you, thank you! I've been needing this explanation for years. This was incredibly helpful.

  • @javpaw1
    @javpaw1 Před 7 lety +76

    My brain is crying tears of joy

  • @bengikoseoglu9303
    @bengikoseoglu9303 Před 2 lety

    Amazing! After going through several text books and articles, I finally understood what eigenvalues and eigenvectors are! Thanks a lot guys, really awesome job :)

  • @indranisensarma9747
    @indranisensarma9747 Před 3 lety

    Would like to thank you for making the subject so accessible to even high school students like myself. I solved the question asked and it was a real treat! Binet's formula appears out of nowhere...just amazing! This series has helped me so much! Thank you once again.

  • @asmkwo
    @asmkwo Před 4 lety +3

    I almost crying... It's just amazing to feel all the blury data in my brain suddently become cristal clear... I will never thank you enough for making this content for free... I'll tip something to you, i owe you. Thank you, and god bless 3b1b

  • @harshkn
    @harshkn Před 7 lety +6

    I was waiting for Eigen vectors video since you started this series. Thanks! Appreciated :)

  • @TheFarmanimalfriend
    @TheFarmanimalfriend Před rokem +3

    I had 'weak' background in math when I first encountered them in quantum theory (chemistry). They almost blew me out of the water! I wish I had had access to this kind of video back in my undergraduate days. Mathematics is really cool.

  • @alessandra2855
    @alessandra2855 Před 3 lety

    this was amazing. saved me a lot of time of struggling trying to visualize everything. may whatever you believe in bless you

  • @kopakanuva
    @kopakanuva Před 5 lety +6

    This is absolutely amazing. Exactly what I was looking for, thank you.

  • @henriquegomes100
    @henriquegomes100 Před 4 lety +7

    I love the dramatic phrases on the begging. It's nice to see someone who loves mathematics so deeply.

  • @alicetokarnia1899
    @alicetokarnia1899 Před 2 lety

    Math can always brings to mind the wonders of making a concept so understable , so simple ... And make many solutions reachable . Thank you very much, Grant.

  • @GameTimewithKirby
    @GameTimewithKirby Před 2 lety +1

    The first time I used eigenvectors and eigenvalues was in my continuum mechanics class. We used the symmetry of the stress tensor to find n number of eigen vectors and eigenvalues to predict crack growth in linear elastic solids. This video is definitely nice to freshen up on the theory behind eigenvectors and eigenvalues.