Dr. Will Wood
Dr. Will Wood
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The Revolutionary Genius Of Joseph Fourier
To try everything Brilliant has to offer-free-for a full 30 days, visit brilliant.org/DrWillWood . You’ll also get 20% off an annual premium subscription.
In this video, we explore the life and work of Fourier, culminating in the famous Fourier Series.
FAQ : How do you make these animations?
Animations are mostly made in Apple Keynote which has lots of functionality for animating shapes, lines, curves and text (as well as really good LaTeX). For some of the more complex animations, I use the Manim library. Editing and voiceover work in DaVinci Resolve.
Supporting the Channel.
If you would like to support me in making free mathematics tutorials then you can make a small donation over at
www.buymeacoffee.com/DrWillWood
Thank you so much, I hope you find the content useful.
This video was sponsored by Brilliant
Переглядів: 95 252

Відео

Dirichlet Invented this Function to Prove a Point
Переглядів 214 тис.2 місяці тому
In 1829, Dirichlet invented the first nowhere continuous function. FAQ : How do you make these animations? Animations are mostly made in Apple Keynote which has lots of functionality for animating shapes, lines, curves and text (as well as really good LaTeX). For some of the more complex animations, I use the Manim library. Editing and voiceover work in DaVinci Resolve. Supporting the Channel. ...
This Function Maps Any Interval to the Real Line (Conway's Base-13 Function)
Переглядів 70 тис.10 місяців тому
In this video we'll explore Conway's "Base-13 function" which maps any real interval to the real line. It is a function which is discontinuous everywhere, yet still has the intermediate value property: making it a counter example to the converse of the intermediate value theorem. #some3 FAQ : How do you make these animations? Animations are mostly made in Apple Keynote which has lots of functio...
Minimax Approximation and the Exchange Algorithm
Переглядів 12 тис.Рік тому
In this video we'll discuss minimax approximation. This is a method of approximating functions by minimisation of the infinity (uniform) norm. The exchange algorithm is an iterative method of finding the approximation which minimises the infinity norm. FAQ : How do you make these animations? Animations are mostly made in Apple Keynote which has lots of functionality for animating shapes, lines,...
Pick's Theorem (From Euler's Planar Graph Formula)
Переглядів 4,7 тис.Рік тому
In this video we'll discuss Pick's Theorem: probably the most famous theorem in lattice geometry. We'll use Euler's results from graph theory (namely, his planar graph formula) to prove this theorem. References and Notes: Ref. 1. This proof is given in full in Garbett (2010) - documents.kenyon.edu/math/GarbettJSenEx2011.pdf Also see Ref. 1 for proof that any primitive lattice polygon can be div...
A really Satisfying Proof about Triangles on a Lattice.
Переглядів 4 тис.Рік тому
In this video we'll discuss an important result in lattice geometry: All primitive lattice triangles have and area of 1/2. Incidentally, the method of proof shows that all primitive lattice parallelograms have an area of 1. #SOME2 References and Notes: Ref. 1 This proof is entirely based on Garbett (2010) - documents.kenyon.edu/math/GarbettJSenEx2011.pdf Ref 2. This video shows how the determin...
The Riemann Zeta Function in the Integer Lattice
Переглядів 10 тис.Рік тому
In this video we discuss visible points on the integer lattice and it's connection to the Riemann zeta function. Sources: 1. The main derivation was based on the blog post shreevatsa.wordpress.com/2008/11/07/lattice-points-visible-from-the-origin/ 2. A slightly more formal version of the argument given above for the probability of two integers being coprime is given in the introduction in: hal....
How Newton discovered Taylor series (but didn't tell anyone)
Переглядів 32 тис.2 роки тому
In this video we explore the independent discovery of Taylor series by Isaac Newton and the manuscript which "never left Newtons hands". Chapters 0:00 - Introduction 01:55 - James Gregory's discovery 04:22 - Isaac Newton's discovery 06:23 - Outro In-video References: 1. Meijering, E., 2002. A chronology of interpolation: from ancient astronomy to modern signal and image processing. Proceedings ...
Newton Interpolation and Divided Differences
Переглядів 33 тис.2 роки тому
In this video, we introduce the Newton Interpolation method and Divided Differences. We start with the general concept, then the recurrence relation and the divided difference table. Finally, we run through a quick example in order to understand how the method is used in practice. Chapters 0:00 - Introduction 05:40 - The Recurrence Relation 10:56 - The Divide Difference Table 12:48 - Example Er...
MSc Mathematics at The Open University
Переглядів 11 тис.2 роки тому
This video is intended to give you an overview of the postgraduate course MSc Mathematics at The Open University. The way I see it, this video will give you a flavour of the course and how it works without being too overwhelming with the details. Please note that module costs shown in the video are for UK students. Links: The Course - www.open.ac.uk/postgraduate/qualifications/f04 Diagnostic Qu...
Bijective Functions and the Continuum Hypothesis
Переглядів 14 тис.2 роки тому
This video is largely about bijective functions. Specifically why bijective functions have inverses, why bijective functions can be used to show two sets are the same size and how the continuum hypothesis can be written as a statement about bijections. Chapters: 0:00 - Introduction 01:02 - Definitions 03:32 - Inverses 05:28 - Cardinality 08:29 - Continuum Hypothesis The product links below are ...
Relations and Functions: The Modern Definition of a Mathematical Function.
Переглядів 12 тис.2 роки тому
In this video, we discuss how the definition of a function has changed over time, largely due to the development of set theory. Chapters 0:00 - Introduction and Motivation 01:50 - Products of Sets 02:53 - Relations 03:59 - Functions The product links below are Amazon affiliate links. If you buy certain products on Amazon soon after clicking them, I may receive a commission. The price is the sam...
The Vandermonde Matrix and Polynomial Interpolation
Переглядів 45 тис.2 роки тому
The Vandermonde matrix is a used in the calculation of interpolating polynomials but is more often encountered in the proof that such polynomial interpolates exist. It is also often encountered in the study of determinants since it has a really nice determinant formula. Chapters 0:00 - Introduction 01:01 - Uniqueness 02:30 The Vandermonde Matrix The product links below are Amazon affiliate link...
An existence proof for arbitrarily large prime gaps.
Переглядів 62 тис.2 роки тому
In this video we'll discuss prime gaps. In particular, we'll prove that there are arbitrarily large gaps between two consecutive prime numbers. The product links below are Amazon affiliate links. If you buy certain products on Amazon soon after clicking them, I may receive a commission. The price is the same for you, but it does help to support the channel :-) This video was based on an exercis...
Lagrange Interpolation
Переглядів 132 тис.2 роки тому
Lagrange Interpolation
The Fundamental Theorem of Arithmetic
Переглядів 14 тис.2 роки тому
The Fundamental Theorem of Arithmetic
Padé Approximants
Переглядів 434 тис.2 роки тому
Padé Approximants
Set Theory | All-in-One Video
Переглядів 736 тис.2 роки тому
Set Theory | All-in-One Video
A Tour of the Real Numbers
Переглядів 7 тис.3 роки тому
A Tour of the Real Numbers
Convex Norms and Unique Best Approximations
Переглядів 12 тис.3 роки тому
Convex Norms and Unique Best Approximations
Convex Sets | Introduction, Definition and Examples
Переглядів 18 тис.3 роки тому
Convex Sets | Introduction, Definition and Examples
Approximating Functions in a Metric Space
Переглядів 55 тис.3 роки тому
Approximating Functions in a Metric Space
The Lp Norm for Vectors and Functions
Переглядів 73 тис.3 роки тому
The Lp Norm for Vectors and Functions
Normed Linear Spaces | Introduction, L1 and L2 Norms
Переглядів 25 тис.3 роки тому
Normed Linear Spaces | Introduction, L1 and L2 Norms
Metric Spaces
Переглядів 26 тис.3 роки тому
Metric Spaces

КОМЕНТАРІ

  • @frozenturtl827
    @frozenturtl827 День тому

    25:32 i don't understand the bottom statement as true what im reading it as goes as thus: the left side has two parts, the first part is inside the parenthesis and basically says "a set that is both prime and less than 100" and the second part is the C which basically says "everything except that set". that's cool, makes sense the right side basically says that it is a set that contains two general sets, the first set is all numbers that are not prime (the prime with a C). the second set is that is also contains all numbers greater than 100. With those definitions, it's clear that the right side contains both numbers like 4, 6, and 9; and also, numbers like 110, 220, etc. this is because it has a UNION and not an intersection. HOWEVER the left side says that the numbers are everything EXCEPT "numbers that are prime and less than 100". This means that the left side contains numbers like 110, 220, etc, but NOT numbers like 4, 6 and 9. Now, i'm not stupid, i know that i'm not disproving this guys theorems. the question i have is where am i making a mistake? i don't understand the logic behind the sentence and equation? can anyone help?

  • @caw25sha
    @caw25sha 2 дні тому

    The droning noise makes this completely unwatchable. Why do that?

  • @deakzoltan2714
    @deakzoltan2714 3 дні тому

    Great video! It would have been really nice to see the actual approximation as a 3D function (the values over the x-y plane), not only the section at x=0.

  • @OpenSourceAnarchist
    @OpenSourceAnarchist 3 дні тому

    I love Will Wood's music, but he's an even better mathematician :) <3

  • @Halleluyah83
    @Halleluyah83 5 днів тому

    Вся разница вот в чем: Тэйлор предложил полиномиальное разложение в ряд, а Падэ - рациональное приближение.

  • @fork8972
    @fork8972 5 днів тому

    @DrWillWood 10:34 Should be 0.073, instead of 0.73.

  • @Poor_Devil
    @Poor_Devil 6 днів тому

  • @jimwarden1121
    @jimwarden1121 7 днів тому

    Night before exam! Yess 4am

  • @NotAGerman
    @NotAGerman 7 днів тому

    Math exam tomorrow. I love you

  • @brian.westersauce
    @brian.westersauce 9 днів тому

    Love those multilevel narketing campaigns

  • @davidolufemi-hs9wj
    @davidolufemi-hs9wj 9 днів тому

    Nice…✨ Nice choice of background sound btw…

  • @tuo9433
    @tuo9433 9 днів тому

    Dear Dr Will Wood. Can you explain the relationship between equation at 4:27 and Newton's cooling law? At first glance it seems to make sense, but in Newton Law of Cooling there is no spacial variable? Also the unit of 2 equations is not the same. For Newton's law of cooling, the unit of dQ/dt is Watt, but for the second equation, the unit is W/m. Can you help explain this?

  • @gbgnygtfvr5v114
    @gbgnygtfvr5v114 9 днів тому

    Wait doesn't he sound like the guy who explained different dimensions xkcdhstguy???

  • @ronaldjorgensen6839
    @ronaldjorgensen6839 10 днів тому

    thank you DR.

  • @fizzygrapedrink4835
    @fizzygrapedrink4835 10 днів тому

    Such a great video! I'm cramming for exams in my uni right now, and this was super useful and pleasant to listen to! Way more understandable than our professor's notes lol

  • @beagleboy31
    @beagleboy31 11 днів тому

    The last point really drives home what a monstrosity this function is

  • @isaz2425
    @isaz2425 11 днів тому

    What would be the integral of this function ? (between 0 and 1 for example) Undefined ? 1/2 ? some other ratio ?

  • @tobuslieven
    @tobuslieven 11 днів тому

    I didn't know that there's a rational number between any two irrationals. Because there's also an irrational between any two rationals, does that mean you can't go from one irrational to another without going through a rational, so the number line alternates in some sense between rationals and irrationals?

  • @SIMITechIndia
    @SIMITechIndia 11 днів тому

    won't the l2 norm be a circle instead of a square at each point. i.e. similar to a making a 3D shape by rotating each point of g(x) about f(x) as center and then taking the volume of that shape. Of course we are then applying a square root after this.

  • @tylerfoss3346
    @tylerfoss3346 13 днів тому

    Involved in the Reign of Terror.......imprisoned and survived prison? So, he wasn't "involved" in the Reign of Terror but he WAS imprisoned during the Reign of Terror. Why was this?

  • @KunalWaghalkar890
    @KunalWaghalkar890 13 днів тому

    What is cardinality of set A= { 1, 2, 3, 3, 3 }

  • @philipoakley5498
    @philipoakley5498 13 днів тому

    The point about the set being 'limited' to what supposed to be in it, as opposed to the content of some wider set (e.g. thinking 'all even numbers' is the set of natural number) is a mistaken perception. Part of that problem is that there is a confusion between 'counting' and the labels of the objects of the set (such as 'numbers'). The label '1', and the count of 'first element' are (can be) conceptually distinct things. This matters when explaining that the size of the 'even numbers' and the size of the whole numbers are both the same because you can count (bijectionaly) both of them. Another example is software engineers who like to start at 'zero' (also labelled '0') as their first element of their set that's an ordered list/array. Their 'forever' is 0 to (aleph.null-1) ;-)

  • @That1CelloGuy
    @That1CelloGuy 14 днів тому

    Okay, but what's the Fourier transform of this function?

  • @DavidConnerCodeaholic
    @DavidConnerCodeaholic 14 днів тому

    There is a definition of phi as the most irrational number, where it’s written as a continuous fraction of ones all the way down. If two takes the place of the last digit in this continuous fraction construction for phi, then those two numbers are not separated by a rational number. I think this runs into some methodological issues. However, you can do this digit substitution with finite values of phi, for which it is possible to find a rational number. It is only problematic to find it when the digits occur at the end. Still, any continuous fraction can be flipped inside out, though you may run into problems with infinity, though an equality sign by definition makes an equation finite if one side has finite value.

  • @hyperexplorer5355
    @hyperexplorer5355 14 днів тому

    Thank you so much for your videos!.

  • @jonathanccast
    @jonathanccast 15 днів тому

    Where Fourier?

  • @JessicaKMcIntosh
    @JessicaKMcIntosh 15 днів тому

    Lovely as always. 💜

  • @sciencefordreamers2115
    @sciencefordreamers2115 15 днів тому

    Amazing quote for Fourier in the beginning ! Thank you!

  • @satishgupta2658
    @satishgupta2658 16 днів тому

    Top 16 greatest mathematicians of all time 👇 Carl Friedrich Gauss Euler Newton Euclid Archimedes Leibniz Pierre Laplace Joseph Fourier Bernhard Riemann George Cantor Rene Descartes Alan Turing David Hilbert Kurt Gödel Fermat George Boole

  • @gorkyrojas9346
    @gorkyrojas9346 16 днів тому

    I expected this to lead somewhere.

  • @TerryGiblin
    @TerryGiblin 16 днів тому

    Dear Will, thank you. You have answered a question, I have been pondering for the past 42 years. As I watched your video, I was teleported back, "through space and time" to the summer of 1982. I was studying Fourier analysis and I had an epiphany, the first time my "wave function collapsed". I simply realized,"If you give me any function, any function f(x), I can express it in terms of a simple combination of sines and cosines." - Pure mathematics at its best, QED. Or as Sidney Coleman said it, "The career of a young Theoretical Physicist consists of treating the harmonic oscillator in ever increasing levels of abstraction."

  • @Neuroszima
    @Neuroszima 16 днів тому

    Wait, how is one part or the other, contiuous, at the end of video?

  • @CSDragon
    @CSDragon 16 днів тому

    ......so what was the fourier transform of the dirichlet function? You said he invented it to prove a point but never said how it proves that point

  • @VolumetricTerrain-hz7ci
    @VolumetricTerrain-hz7ci 17 днів тому

    There are unknown way to visualize subspace, or vector spaces. You can stretching the width of the x axis, for example, in the right line of a 3d stereo image, and also get depth, as shown below. L R |____| |______| TIP: To get the 3d depth, close one eye and focus on either left or right line, and then open it. This because the z axis uses x to get depth. Which means that you can get double depth to the image.... 4d depth??? :O p.s You're good teacher!

  • @eliasbranchereau5354
    @eliasbranchereau5354 17 днів тому

    thank you so much, this is what the future of education looks like

  • @pauleugenio5914
    @pauleugenio5914 18 днів тому

    My mind 🧠 🤯

  • @oniondeluxe9942
    @oniondeluxe9942 18 днів тому

    This will only work as long as the PDE is linear, right?

  • @stighenningjohansen
    @stighenningjohansen 18 днів тому

    Nope

  • @mks3782
    @mks3782 18 днів тому

    Cant see any bound between Fourier's lifestory and his maths solution. I dont mean that autor was wrong when added history to this video, but it need better connection of scenario parts.

  • @sillystuff6247
    @sillystuff6247 19 днів тому

    wish i could listen to this but your decision to add unneeded background music interferes with understanding.

  • @andrewporter1868
    @andrewporter1868 19 днів тому

    Epic video as usual; never fails to disappoint. You upload too little and too late 😔

  • @andrewporter1868
    @andrewporter1868 19 днів тому

    That which is like to itself in differentiation and exponentiation must be directly related to the exponential function, and Gamma(z) is equal to it for certain values, and seems to oscillate between cosine and sine at multiples of 1/2. In fact, it seems to act like a generalization of exp(z), and Gamma does after all show up in the partial sum of exp(z) itself which would also seem to imply a way to possibly generalize factorial given a means to compute the nth digit of e in some base? So far, my guess is there's probably a sum of four independent terms involving the exponential which I hypothesize from the likeness and alternative representation of the simple sum of complexes z + w as z+w=\left(\sqrt{z}+i\sqrt{w} ight)\left(\sqrt{z}-i\sqrt{w} ight)=\frac{1}{2}\left(e^{-i\arccos\sqrt{z}}+e^{i\arccos\sqrt{z}}+i\left(e^{-i\arccos\sqrt{w}}+e^{i\arccos\sqrt{w}} ight) ight)\cdot\frac{1}{2}\left(e^{-i\arccos\sqrt{z}}+e^{i\arccos\sqrt{z}}-i\left(e^{-i\arccos\sqrt{w}}+e^{i\arccos\sqrt{w}} ight) ight). Consider also product_(n=0)^(k) (x + i n) and the particular products with which this product converges as k goes to infinity. All of this leads me to believe that perhaps there's some simple sort of representation by generalizing the imaginary unit if not the complexes in a particular way such that something simple along the lines of f(z)^n = Gamma(f(z) + n)/Gamma(f(z)). With that, and with being able to represent any Gamma(z) for z in the rectangular region [0, 1 + i] (or really any such region [n+ik, n+1 + ij] for integers n, k and j), both representing Gamma sufficiently with which to create some sort of symbolic arithmetic (provided certain comparative operations can be performed symbolically), as well as computing arbitrarily good approximations of Gamma(z), would be trivialized-and that's just what I'm looking for. Am still sad I didn't get addicted to complex arithmetic sooner 😔

  • @takyc7883
    @takyc7883 20 днів тому

    what a genius

  • @allnickla
    @allnickla 20 днів тому

    Ok

  • @allnickla
    @allnickla 20 днів тому

    ?

  • @xelth
    @xelth 21 день тому

    Can you tell about decomposition over Bernstein polynomials? Is it even possible?

  • @user-hq6yp9bo9m
    @user-hq6yp9bo9m 21 день тому

    Very bad 👎👎explaion

  • @urano1988
    @urano1988 21 день тому

    So, can you Fourier transform the Dirichlet function?

  • @larzcaetano
    @larzcaetano 21 день тому

    Hey, man! Amazing video! Loved the background story!!! I would like to know if you can do the same for the Laplace Transform. I did a lot of digging through the years and I actually figured that it just came to be what it is from trial and error. However, I am aware that there is a way to derive it from Fourier Transform. Anyway, would be awesome to see you covering these topics as well!

  • @rexauer9896
    @rexauer9896 22 дні тому

    Can you transfer heat through a photon? Or how about a frequency like gamma or infrared. Or is heat strictly bound to physical matter?