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7
votes
3answers
727 views

Masters' thesis in group theory [closed]

I would like some ideas on topics in group theory which would be suitable for a masters' thesis. What sort of problems would be suitable for this level? Because it is at masters' level, no original ...
5
votes
0answers
77 views

Reference Request: Prereqs for Lecture Notes on “Abstract Linear Algebra”

I just found this set of lecture notes on linear algebra which seems to go over several things I've been wondering about as I study linear algebra. Unfortunately there are very few exercises in the ...
0
votes
2answers
112 views

Open Problems for High School Students

I am a homeschooled rising senior in high school, and I would like to research an open problem in mathematics. I have taken a number of undergraduate-level mathematics courses, including ...
0
votes
1answer
32 views

Unbounded Operators: Notation?

For continuous a.k.a bounded operators we have $\mathcal{B}(X,Y)$ stressing on boundedness and $\mathcal{L}(X,Y)$ stressing on linearity entailing $\mathcal{C}(X,Y)$. Is there a notation for ...
1
vote
3answers
68 views

Related Methods: Lagrange Multipliers

It really pains me to ask this question, but I was working on an optimization problem and wanted to show a friend how we could also use Lagrange Multipliers to solve it. I was considering the ...
1
vote
2answers
115 views

Linear Algebra without Matrices

How far could one get in linear algebra without matrices? It seems like the more I learn, the less I actually use them, but most of the basic theorems and invariants that learned first -- and still ...
3
votes
0answers
72 views

Is there any visual animation to show the basic concept of algebraic geometry? [closed]

Is there any visual animation to show the basic concept of algebraic geometry? There are rarely pictures in textbooks, so are there any animation to show basic but important concepts?
4
votes
1answer
59 views

Defining algebras over noncommutative rings

A definition of "algebra" (that is, an associative algebra, in the sense of ring theory) generally requires a commutative base ring. But there are cases where it's reasonable to consider algebras ...
2
votes
1answer
107 views

Changing streams in PhD

I've a masters degree from a reputed Indian university in pure mathematics, with a specialization in Algebraic Number Theory. However, I'd like to apply for a PhD in computational math/theoretical ...
3
votes
2answers
143 views

Bridging the gap of understanding function terminology in math for a programmer.

I'm a computer programmer by profession with no formal CS education. When I read in mathematics the terminology used around a function, I get confused. For example, I was reading up on some calc and ...
9
votes
3answers
206 views

Areas of contemporary Mathematical Physics

I have often heard that some developments in Physics such as Gauge Theory, String Theory, Twistor Theory, Loop Quantum Gravity etc have had a significant impact on pure Mathematics especially geometry ...
4
votes
3answers
318 views

Interesting Mathematical Fallacies [duplicate]

I recently volunteered to help with a summer math program at a local high school for which I thought would be a breeze. As it turns out, it isn't a program for those catching up (summer school) like I ...
27
votes
15answers
3k views

Ways to study mathematics while commuting

I spend approximately 3 to 4 hours on public transport everyday. I try to maximize the usage of this time by checking email etc on my phone. Are there any tips to study mathematics while commuting? ...
7
votes
3answers
144 views

Algebraically, What Does $\Bbb R$ get us?

In terms of the basic algebraic operations -- addition, negation, multiplication, division, and exponentiation -- is there any gain moving from $\Bbb Q$ to $\Bbb R$? Say we start with $\Bbb N$: ...
0
votes
0answers
41 views

Why Does $e^{ix}=\cos(x)+i\sin(x)$? [duplicate]

Something I've always wondered, but never had a good answer too (I accept there may not be one). I fully understand how to derive this, so I'm not looking for an analytic proof. But rather I cannot ...
2
votes
1answer
103 views

Best Less-Famous Texts for Forcing

There are many books, papers and lecture notes which give an introduction to forcing (e.g. Jech or Kunen's books) but here I am looking for some possibly less-famous useful comprehensive texts for ...
6
votes
6answers
214 views

Interviews of famous modern mathematicians

I was wondering, are there any good collections of interviews of famous modern mathematicians? It can be text interviews, or audio or video recordings. I am not sure what exactly I mean by "modern". ...
1
vote
3answers
55 views

Considering Vectors Geometrically

I have a few questions which a little research (searching the internet through Google) has not satiated. It seems that vectors are very important, even when considering them as the arrows which ...
4
votes
1answer
128 views

Humor in Math Textbooks

So, I was looking though a problem section in Dummit and Foote, and found this amusing "definition." I actually tried googling it, but I can't find any reference to these associated primes being ...
24
votes
8answers
2k views

Complex analysis is more “real” than real analysis

In physics, in the past, complex numbers were used only to remember or simplify formulas and computations. But after the birth of quantum physics, they found that a thing as real as "matter" itself ...
2
votes
1answer
103 views

Is $0$ a valid number? [closed]

I want to know what people think of the number $0$, on it's own. Is it a valid number or not? For example is $6 \cdot 0=0$ a valid equation?
1
vote
2answers
109 views

Help Writing a PDF for a Math Course

I have to write up notes on a math course and would absolutely love to make my notes look very similar to this: Using libreoffice, with texmaths, does anyone know settings, i.e. text format, page ...
2
votes
1answer
55 views

Rigorous Book on Topology of Surfaces and Simplicial Complexes

In the undergraduate course I am on the topology course covered the basics of point set topogly very well and everything was done, but then moved on to simplicial complexes and surfaces which was very ...
0
votes
1answer
22 views

Definition of linear subspace

Let $k<d\in\mathbb{N}$. Given the following definition: $G=\{ S: S\text{ is }k\text{-dimensinal subspace of }\mathbb{R}^d\}$ Would you understand that $G$ contains only "homogeneous linear ...
3
votes
5answers
113 views

Axioms of Euclid

The axioms of Euclid are : Things which are equal to the same thing are also equal to one another. If equals be added to equals, the wholes are equal. If equals be subtracted from equals, the ...
5
votes
2answers
114 views

How much time per day to mathematicians usually spend working?

I was reading Poincare's wikipedia page and I noticed that Poincare only did 4 hours of hard mathematical research a day, preferring to let his subconscious have the rest of the time to attack the ...
0
votes
0answers
55 views

Multivariable calculus and real analysis in one semester. What is the best way to study for such course?

I am in my first year of EECS and planning on taking a lot of maths classes. I have already taken single variable calculus and linear algebra and did well in them and decided to take multivariable ...
-6
votes
1answer
133 views

Why $\epsilon$ is always small? [closed]

Whoever invented this, he must be not aware of democracy. I want $\epsilon$ to be large not small. Also, why $\theta$ is an angle?
15
votes
4answers
2k views

Is there a(n elementary) function whose derivative we cannot integrate?

Say, for example, I take a reasonably-complicated function $f(x)=\tanh[\ln(x^x)]$, and differentiate it to get $$f'(x)=\frac{4x^{2x} [1+\ln(x)]}{(x^{2x}+1)^2}.$$ Now, to integrate this, I imagine, ...
0
votes
4answers
613 views

Prove that every irrational numbers can be approximated by rational numbers. [closed]

Prove that every irrational numbers can be approximated by rational numbers. How can I do it? Ok, I admit. I heard it, I thought it is to be true. And I was a kid. Now I when I think about it, I ...
6
votes
1answer
52 views

What is the difference between a calculus and an algebra? [duplicate]

You can have a lambda calculus, the calculus of the real numbers or a logical calculus but on the other hand you could also have an algebra of sets, a Lie algebra, or a linear algebra. Is there any ...
0
votes
1answer
61 views

Algebra books for olympiad preparation

I was looking for some good books for algebra and number theory at the olympiad level. Does anybody have any suggestions? I specifically want books that work on techniques and concepts (not just ...
4
votes
3answers
278 views

When does injectivity imply surjectivity?

I'm aware of the existence of this question: Surjectivity implies injectivity However, the question is regarding a finite set $S$. I was wondering, though: What happens when $S$ is an infinite set? ...
0
votes
0answers
34 views

Why the need for a proof of the Collatz conjecture [duplicate]

I am just a mathematics student and not a professional so my knowledge is limited regarding the Collatz conjecture. But I struggle to see what could be gained from the proof of the conjecture? Is this ...
0
votes
1answer
21 views

Proof of Equality with Mixed Partials

Here is the link: Hessian I understand everything but this line: $$g(x_0 + \Delta x) − g(x_0) = \frac{dg}{dx} (ξ) \Delta x$$ i.e., $$S (X_0, \Delta x, \Delta y) = \frac{∂φ}{∂x} (ξ, y_0 + \Delta y) − ...
10
votes
1answer
109 views

Why are $L^p$-spaces so ubiquitous?

It always baffled me why $L^p$-spaces are the spaces of choice in almost any area (sometimes with some added regularity (Sobolev/Besov/...)). I understand that the exponenent allows for convenient ...
6
votes
3answers
211 views

Number Theory Reading List

What are the essential number theory texts that every serious student of number theory should read?
6
votes
2answers
85 views

Advice for self-studying Inequalities and Calculus

I'm interested in self-studying the following books over the next year or so: Spivak's Calculus (I'm already in Ch. 5 and it is very slow going) The Cauchy-Schwarz Master Class by J. Michael Steele ...
2
votes
4answers
336 views

What is your intuitive understanding of infinity? [duplicate]

What is your intuitive understanding of infinity? Mine is the following, I prepared it as image: Those were the main points I got to after thinking by myself about what infinity is, without ...
1
vote
1answer
65 views

“Geometric” proof of Rouche's theorem on the number of zeros?

I understand the analytic proof of Rouche's theorem as presented in Stein and Shakarchi's complex analysis - $|f(z)| > |g(z)|$ on the boundary circle C ensures that the argument principle can be ...
3
votes
1answer
81 views

Real analysis with a non-standard topology

I have recently undertaken a self study of topology and am using Munkres Topology 2nd edition as the primary text. My background(theoretical chemistry & physics) is almost entirely void of any ...
0
votes
0answers
23 views

How to find out convergence of sequence of functions in short time.

I was studying about sequence of functions and about uniform and pointwise convergence of these series. To prove or disprove the convergence of sequence of functions we have several methods like by ...
0
votes
1answer
44 views

Writing a chain of implications in English

How to write a theorem of the form $A\Rightarrow B\Rightarrow C\Rightarrow D$ where every $A$, $B$, $C$, $D$ are formulated with words (English) rather than with formulas? One idea: The next item of ...
1
vote
1answer
52 views

What are the problems that you tried to find their solutions and you did not know that it is impossible?

Tell us your story about Mathematics. Have you dream one day to do a big contribution in Mathematics because you are curious and love challenges. What are things that you tried to prove which then ...
1
vote
3answers
122 views

Which course is best to take after calculus, linear algebra, and real analysis?

During my first year at university I took our honors versions of multivariable calculus and linear algebra (which was very abstract) as well as an introductory real analysis course focusing on ...
0
votes
8answers
108 views

Soft question about the square root

I got to thinking about the square root the other day, and there's this thing that bugs me in the back of my mind. As far as I know, $\sqrt{4}$ is unambiguously $2$, and nothing else, as the square ...
19
votes
6answers
831 views

Category-theoretic description of the real numbers

The familiar number sets $\mathbb{N}$, $\mathbb{Z}$, $\mathbb{Q}$ all have "natural constructions", which indicate, why they are mathematically interesting. For example, equipping $\mathbb{N}$ with ...
8
votes
3answers
1k views

Is it bad to keep aside Lang's Algebra in graduate school?

Question is as it is stated in title. I will be joining for PhD program in this July 2014. I am interested in working in Algebra/Algebraic Geometry/Algebraic Number Theory. I tried to learn algebra ...
4
votes
0answers
46 views

Name for a body that can be completely described using its silhouettes

I'm shooting blind over here because I have no background in this field of mathematics. I assume that if you have a body (in $\mathbb{R}^3$), you can call it convex if any segment from one point ...
2
votes
2answers
118 views

Applications of groups, rings and modules in life [closed]

I have read calculus. Now I'm reading algebra. What is the application of groups, rings and modules in life? When we study derivations we know several applications. What about groups, rings and ...