7,248 reputation
1730
bio website math.arizona.edu/~nhenscheid
location Tucson, AZ
age 27
visits member for 1 year, 9 months
seen 1 hour ago

Studying for an applied math PhD at the University of Arizona. BS & MS from Western Washington University. When I'm not doing math, I'm climbing rocks.


Aug
21
comment Intuition behind accelerated first-order methods
I should know this, because I use Nesterov's method frequently, but I can't think of a good intuitive explanation off hand. If I wasn't so busy I would look over my optimization notes and figure this out...if no one answers in the next few days I will.
Aug
21
comment Reference for Generalized Eigenvectors
Linear Algebra Done Right by Axler or Linear Algebra and its Applications by Lax come to mind. I'm sure there are others.
Aug
20
awarded  Nice Answer
Aug
20
revised Dual norm intuition
added 1311 characters in body
Aug
19
comment Dual norm intuition
This is essentially what I said, but in many fewer words. +1.
Aug
19
answered Dual norm intuition
Aug
19
comment Program for writing a Bachelor Thesis.
Using a program like TeXmaker will make taking the initial plunge easier. It's worth it.
Aug
18
comment I need help finding a rigorous Pre-calculus textbook
I'm glad I'm not the only one who dislikes modern textbooks...I have to teach out of them!
Aug
6
answered Free solvers in C/C++ for convex integer programming
Jul
30
comment Cauchy-Riemann and Analytic Functions
Check your answer for $V_y$.
Jul
29
comment Can Hilbert spaces generalize non-Euclidean geometry by having the sum of the angles of a triangle not be equal to pi?
This isn't enough for an answer, but one suitable generalization might be infinite dimensional manifolds. They have seen some use in e.g. the theory of PDE, namely fluid flow.
Jul
27
comment Is this a valid proof of $\lim _{n\rightarrow \infty }(1+\frac{z}{n})^n=e^z$?
For the third point, $n$ and $z$ being independent is unfortunately not enough - the sequence $\frac{d}{dz}g_n(z)$ must converge uniformly. See e.g. here
Jul
27
answered Is this a valid proof of $\lim _{n\rightarrow \infty }(1+\frac{z}{n})^n=e^z$?
Jul
27
comment If there is the inverse operator of the operator A, then $(A^{-1})^{-1}=A$?
What kind of operator are we talking about? What are your spaces?
Jul
27
answered Is Dirac's delta function well-defined at Lebesgue points?
Jul
27
comment Is Dirac's delta function well-defined at Lebesgue points?
Isn't the point of Lebesgue points sort of that at these points point values do make sense? I hadn't thought about it that way until now.
Jul
24
comment Basis representation for non-negative, compact support, reasonably smooth spectral function
B-splines.
Jul
24
comment Operator $Au(t) = \int_0^t e^{t-s} u(s) ds$ (Proof Verification)
The rest looks good. For (a) it's always good to show that for all $u$ with $\|u\|_\infty\leq 1$, we have $\|Au\|_\infty\leq\|A\|_*$ (simple string of inequalities). Even if you see what the norm is or can compute it, it's still good to prove that it satisfies the correct inequality.
Jul
24
revised Show this is an Open Cover of (0,1)
added full solution.
Jul
24
comment How to memorize the trigonometric identities?
Also, most (American) pre-calc level students haven't learned this.