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Zvi Rosen
United States
Приєднався 18 бер 2020
Hi there!
I am a professor of Mathematics at Florida Atlantic University in Boca Raton, FL. When I teach courses with an online component, I like to upload the video lectures here to share with anyone who might be interested.
In my research, I study applications of algebraic geometry, mainly to biology, but also to statistics, physics, and rigidity theory. When possible, I will link to research talks by myself and my colleagues.
Thanks for your interest and I look forward to studying math with you!
I am a professor of Mathematics at Florida Atlantic University in Boca Raton, FL. When I teach courses with an online component, I like to upload the video lectures here to share with anyone who might be interested.
In my research, I study applications of algebraic geometry, mainly to biology, but also to statistics, physics, and rigidity theory. When possible, I will link to research talks by myself and my colleagues.
Thanks for your interest and I look forward to studying math with you!
History of Calculus 9: Johann Bernoulli
We discuss the life of Johann Bernoulli, Jacob's younger brother. We talk about some of his legendary feuds, then move on to his mathematics. We take a closer look at L'Hospital's rule and Johann's analysis of the function y = x^x. This exposition is based on Chapter 3 of "The Calculus Gallery" by William Dunham.
Переглядів: 53
Відео
History of Calculus 8: Jacob Bernoulli
Переглядів 1619 годин тому
In this lecture, we will discuss the legacy of one of Leibniz's proteges, Jacob Bernoulli. After an overview of his life and work, we will focus on his proof of the divergence of the harmonic series as well as his computation of several figurate series. Our exposition follows Chapter 3 of "The Calculus Gallery" by William Dunham. In the video, we make reference to the Mathologer video on Bernou...
History of Calculus 7: Wilhelm Gottfried Leibniz
Переглядів 31114 днів тому
In this lecture, we will discuss the life and contributions of Wilhelm Gottfried Leibniz. In particular, we detail the controversy between Leibniz and Newton about whether Leibniz plagiarized his calculus from Newton. We explain why despite Leibniz's humiliation in his own lifetime, his version of calculus was more enduring. Then, we go on to prove Leibniz's transmutation theorem, and use it to...
History of Calculus 6: Sir Isaac Newton
Переглядів 11914 днів тому
In this lecture, we talk about some of the mathematical predecessors to Newton & Leibniz, the feuding inventors of calculus. While a lot of the content of calculus was already out there, Newton & Leibniz were the first to systematize calculus as a toolbox. After this background, we run through Newton's biography and some particularities of his method of "fluxions." Finally, we work through some...
History of Calculus 5: Madhava
Переглядів 159Місяць тому
In this lecture, we will speak briefly about mathematics in ancient India and the School of Kerala. For most of the lecture, we describe Madhava's strategy for calculating series expansions of sin(x) and cos(x). This article was our source for Madhava's strategy: www2.kenyon.edu/Depts/Math/Aydin/Teach/Fall14/128/CalcIslamIndia.pdf
History of Calculus 4: Ibn al-Haytham
Переглядів 182Місяць тому
In this lecture, we will briefly discuss the setting of the Islamic Golden Age, then dive into a calculation by Ḥasan Ibn al-Haytham. In order to compute the volume of a solid of revolution, he calculated summation formulas for powers of consecutive integers. This article was very helpful in learning about Ibn al-Haytham: www2.kenyon.edu/Depts/Math/Aydin/Teach/Fall14/128/CalcIslamIndia.pdf Insp...
History of Calculus 3: Babylonia
Переглядів 59Місяць тому
In this video, we discuss Babylonian mathematics. We focus on their iterative algorithm to compute square roots. This involves a sequence rapidly converging toward a desired value, thus looking forward to the calculus. I found this article enlightening as I was preparing for this video: www.cantorsparadise.com/a-modern-look-at-square-roots-in-the-babylonian-way-ccd48a5e8716
History of Calculus 2: Archimedes
Переглядів 90Місяць тому
We will discuss the amazingly innovative Archimedes and his application of the method of exhaustion to computing the area of a parabolic segment and calculating an approximate value for pi to within .002 of the true value! The method of exhaustion is an ancient forerunner to the integral. This lecture was recorded for the course MHF 6410 at Florida Atlantic University. We will do a few lectures...
History of Calculus 1: Zeno
Переглядів 157Місяць тому
In this lecture, we will describe the topics we are referring to when we say "calculus". Then, we will begin our journey through history starting with glimpses of the calculus in ancient Greece. We will first discuss the paradoxes of Zeno. This lecture was recorded for the course MHF 6410 at Florida Atlantic University. We will do a few lectures on ideas from calculus prior to Newton & Leibniz,...
Flat Modules (Commutative Algebra 10)
Переглядів 3919 місяців тому
In this lecture, we'll begin with the failure of the tensor product to induce an exact functor. This motivates the definition of flat modules, which DO induce exact functors. We will also present a proposition from Atiyah-MacDonald about various equivalent formulations. In order to provide some motivation, we give a linear algebra-based explanation from nLab (ncatlab.org/nlab/show/flat module#I...
Operations on Ideals (Commutative Algebra 3)
Переглядів 5129 місяців тому
In this lecture, we'll discuss several operations that can be done on ideals of a commutative ring: sum, product, intersection, radical, extension and contraction. We'll also compute examples in the context of the integers and polynomial rings. Corresponds roughly to pages 6-10 of Commutative Algebra by Atiyah-MacDonald.
Introduction (Commutative Algebra 0)
Переглядів 1,3 тис.9 місяців тому
In this lecture, I will describe some problems in Number Theory, Invariant Theory, and Algebraic Geometry which historically motivated the systematic development of Commutative Algebra in the 19th and 20th centuries. In particular, we'll mention Fermat's Last Theorem, Dedekind Domains, polynomial invariants, Hilbert's Basis Theorem, algebraic varieties, and Hilbert's Nullstellensatz. The exposi...
The Commutator Subgroup (Dummit & Foote 5.4 A)
Переглядів 1,4 тис.11 місяців тому
We'll discuss the commutator subgroup G' = [G,G] of a group G. First, we define terms, then prove properties like normality, and the fact that the quotient G/G' is abelian. Finally, we'll compute the derived series of D8, S4 and S5. This connects to the first part of Section 5.4 of Dummit & Foote
"The order of G is n. Prove G is not simple."
Переглядів 22911 місяців тому
In this video, we will describe a general approach to this type of problem which often appears on algebra exams. This fits into the Abstract Algebra course after discussing Sylow's Theorems (Dummit & Foote Chapter 4.5). We'll do examples for n = 200, 80, 160, 90.
Subgroups Generated by Subsets (Dummit & Foote 2.4)
Переглядів 405Рік тому
In this lecture, we'll describe two different ways to build a subgroup containing a specified set of elements A. Then we will show the two ways are equivalent. Finally, we show how the size of a subgroup is related (or unrelated) to the orders of the elements in A.
Stabilizers, Kernels & Conjugation (Dummit & Foote 2.2)
Переглядів 318Рік тому
Stabilizers, Kernels & Conjugation (Dummit & Foote 2.2)
MAS 6318 Final Project: Quadratic Equations (Eda & Junet)
Переглядів 80Рік тому
MAS 6318 Final Project: Quadratic Equations (Eda & Junet)
MAS 6318 Final Project: Polygons, Polytopes & Symmetry (Nicole, Oscar, & Shahina)
Переглядів 59Рік тому
MAS 6318 Final Project: Polygons, Polytopes & Symmetry (Nicole, Oscar, & Shahina)
Alg & Geo 12: Intersection Multiplicity by Resultants
Переглядів 174Рік тому
Alg & Geo 12: Intersection Multiplicity by Resultants
Alg & Geo 11: Intersection Multiplicity by Power Series
Переглядів 180Рік тому
Alg & Geo 11: Intersection Multiplicity by Power Series
Alg & Geo 9: Geometry of Conic Sections
Переглядів 752 роки тому
Alg & Geo 9: Geometry of Conic Sections
Alg & Geo 8: Quadratic Equations and Conic Sections
Переглядів 1142 роки тому
Alg & Geo 8: Quadratic Equations and Conic Sections
Alg & Geo 6: Complex Numbers and Regular n-gons
Переглядів 862 роки тому
Alg & Geo 6: Complex Numbers and Regular n-gons
Alg & Geo 5: The Field of Constructible Numbers
Переглядів 2152 роки тому
Alg & Geo 5: The Field of Constructible Numbers
Alg & Geo 4: Shapes, Equations, and Intersections
Переглядів 1012 роки тому
Alg & Geo 4: Shapes, Equations, and Intersections
🙏🙏
HI, Professor. thank you for all the knowledge that you provide to us . your videos deserve millions views , you explain all good and in the easy way to understand. 10/10 👌
Great video, many thanks.
Great work... from deevige bangalore
@ZviRosen, can I email you some questions about one of your videos on commutative algebra. It has to do with ideal quotients.
Depending on the complexity, it may take me a bit of time to be respond, but absolutely.
For some reason, the proofs of many theorems in this lecture include even fewer details than those in Atiyah and Macdonald.
Can you share the lecture note?
I will try to remember to post the lecture notes from these and share a link when I get a chance.
What does it meant "specialize" here 26:55?
Good question. Intuitively, just plug in "1/f" wherever you see "y" and the equation should still hold; after all, y is an arbitrary unknown. More formally, you could think about this as applying a homomorphism from k[x,y] to the localization k[x,f^{-1}] sending y to f^{-1}.
@@zvirosen753 That makes sense, I apreciate your answer. BTW this is unrelated but I am trying to find a good reference book/paper about I-adic topology/completions. If you happen to know any it will be highly appreciated.
24:53 here A=R=any commutative ring, I guess?
Great lecture! But wait, Gauss' proof of the fundamental theorem is considered faulty? My day is ruined.
Oh, perhaps he also gave a correct proof?
nice!
THANK YOU VERY MUCH PROFESSOR. Your lessons are very interesting 👍👍👍
Ohh, I see now why this very specific elements generate the submodule necessary to define the tensor product of the A-modules. How didn't I see that before. Thanks so much. Your explanation was very clear.
thanks a lot sir, master study is topolojy and now phd is algebra. so ıt was diffucult to understand such that flat modul. can ı get much more notes for flat module
Thanks for watching! I agree flat modules are a hard topic to develop intuition for. I did my best in the "Flat Modules" lecture in this series: ua-cam.com/video/cLPAiRZMY5o/v-deo.htmlsi=LrTgHDBvSr-ii6oq Hope it helps!
Thank you so much for explaining it like this🙏
At 20:05, I’m not sure what it means 0 is not a closed point. Since the closure of {zero ideal} is not itself but Spec Z, set of zero ideal is not closed in Spec Z? Can you help to elaborate more?
I think I get the idea. The set containing prime ideal p, {p} is closed in SpecZ if, {p}=V(p). So { <0> } is not closed. More than that, the closed points of SpecZ are exactly the elements of mSpec Z
Is localization only useful for algebraic reasons, or can we also get density and thus convergence? Lice real numbers can be seen as completion of the set of rationals, is there a similar concept for other sets of localized sets?
I would recommend reading Chapter 10 of Atiyah-MacDonald which discusses completions of Noetherian local rings. I don't think that the reals as completion of the rationals can be recast in this algebraic language, but certainly the p-adics can be.
Perhaps chapter 11? Wow that's a hefty book. I took a look.
Very impressive lecture ... Please also make lectures on advanced group theory
Very good
How can we describe the submodules of S−1M over S−1A.
34:00 Why is it that 1-v0 has to be invertible for v0 in m?
m is a *unique* maximal ideal for B. If (1-v0) is not invertible, then it generates a proper ideal which must be contained in m. But then (1-v0) + v0 = 1 is in m, contradiction.
@@zvirosen753 okay, I lost track of m being unique. Thank you very much.
Thank you for posting the videos!
Please do more topics on Dummit and foote.
There's a tiny mistake around 20:15; we should rather take y=-1 to get x, we get 2-x as is.
Hi Zvi, which software are you using to draw on the white board? I have not found any white board tool which really works well. They all either lag my hand or fail to draw smooth curves.
My pipeline is to make a pdf in Beamer with white space where I want to write, load it up in xournal++ (in Ubuntu Linux), and use my Wacom drawing tablet to write on it. For screen recording, I use vokoscreen.
why do you define a "multiplicatively closed set". Why not simply say it is a "multiplicative monoid"? that already has 1, associativity, and closure. Right? associativity comes for free because it consists of elements from ring A. Right? Whenever I have a new definition for something that sounds awfully like something that already exists, I sweat wondering what is the subtle different that I'm not seeing. Are you claiming by avoiding the work "monoid" that you don't need associativity for some reason?
Nice question! Sadly, the answer is boring: I'm following the convention in most commutative algebra texts. And Wikipedia for that matter: en.wikipedia.org/wiki/Multiplicatively_closed_set
@@zvirosen753 according to the Wikipedia article you mentioned, multiplicatively closed sets are equivalent to monoids. So I don't see the need for redundant confusing terminology.
Your proof of Pascal's Theorem is incomplete. To assure that the conic F divides your polynomial g, you must assume that the conic is irreducible. Otherwise you can't guarantee that the entire conic divides the polynomial g. With this in mind, you can't prove the Pappus' Theorem based of the Pascal one, taking into account that the union of two lines forms a reducible conic (not an irreducible one).
can you give me the exercise of the tensor product of the module on a non - commmmutative ring .thank you
I was looking. For these thank you
Love how you used green pen for tropical semi ring
6:34 should there be I(X), not V(X)?
You are correct!
The example for D.C.C. is actually a special case of Prüfer group, the chain conditions are also studied in Hungerford's Algebra where he introduces these conditions on groups in order to prove Krull-Schmidt theorem :)
this is great
These lectures are great! Really appreciate it. And also I would like to share a math study message here for anyone who might be interested: I would like to read <Presentations of Groups> by D. L. Johnson. And I would like to ask if anyone is interested to read together? Because having a reading partner will make study more fun, especially when go through detail proof together. You are also welcome to share this message to anyone who is interested. Thank you so much!
Was really good to see how assuming a well-defined operation on the equivalence classes of the quotient necessitates that the [e] subgroup is normal. Thank you
Perfect pace and use of proofs. Superb lecturing!
Please post more lectures. Thank you
If [L:K] and [L:F] are finite [k:F] is finite from multiplicative property. For your proof of [K:F] finite how do you know the base vectors from [L:F] are in K, they might be in L-K?
Thanks for the kind words about the lectures! I will keep posting whenever possible. I think you are referring to the Corollary at 10:03. You make a good point that I didn't make explicit! If K is a subspace of L as an F-vector space, then its dimension is bounded above by the dimension of L. Otherwise, you would have a list of n vectors of K linearly independent over F with n > dim L, implying that L also contains more than n linearly independent vectors (since K is in L), contradiction. Another linear algebra result in this spirit is that you can complete any list of linearly independent vectors in a finite-dimensional vector space V to a basis of V.
@@zvirosen753 Thank you for the explanation, I will revisit the lecture with this understanding! I am looking forward to your other lectures. Darren
Brilliant lecture
Really enjoying following along. Is there a syllabus for this course somewhere?
Glad you're enjoying! I will try to post a syllabus to my website soon. In the meanwhile, the texts I'm using are Field Theory and Its Classical Problems by Hadlock, and Ideals, Varieties, and Algorithms by Cox, Little, and O'Shea. We'll discuss Compass and Straight-Edge, Impossible Constructions, Conic Sections, Projective Space, Curve Intersections, and Bezout's Theorem.
Nice, looking forward to following along :)
@13:27 what if one of the polynomials is monic, i.e. the ideal contains 1 ?
Then the initial ideal (in this context) would be the whole ring. I'll stipulate that in some contexts, you want the whole initial term as opposed to just the coefficient to be in the ideal. But that's not the case here. Hope that helps!
19:58 image of z in coker f' (not f)
@38:20 you mean sum of 'finitely' many cyclic modules ?
Yes! Thanks for the correction.
awesome class thank you :D
Super explanation sir, thank you so much sir
Good sir ge
Your lectures are great. Are you planning new series on homological algebra or algebraic geometry or representation theory etc And 28:10 what does it force to be an algebraic extension ? If not k[bar(x)] would be a ring instead of a field ? Is this the reason ? Thanks in advance
Thank you for the kind words! Sorry that I missed your comment & question when you first posted. Yes your guess is exactly right. If x^(-1) is in k[x] then we can write x^-1 = an x^n + ... + a1x + a0. Multiply both sides by x and subtract 1, and you find a polynomial satisfied by x.
31:36 what you're saying is not what you're writing
Watching the whole series at 1,5 speed