Skip to main content
Search type Search syntax
Tags [tag]
Exact "words here"
Author user:1234
user:me (yours)
Score score:3 (3+)
score:0 (none)
Answers answers:3 (3+)
answers:0 (none)
isaccepted:yes
hasaccepted:no
inquestion:1234
Views views:250
Code code:"if (foo != bar)"
Sections title:apples
body:"apples oranges"
URL url:"*.example.com"
Saves in:saves
Status closed:yes
duplicate:no
migrated:no
wiki:no
Types is:question
is:answer
Exclude -[tag]
-apples
For more details on advanced search visit our help page
Results tagged with
Search options not deleted user 22815

Partial differential equations (PDEs): Existence and uniqueness, regularity, boundary conditions, linear and non-linear operators, stability, soliton theory, integrable PDEs, conservation laws, qualitative dynamics.

2 votes
0 answers
248 views

long time existence of a nonlinear parabolic equation

I am thinking about a geometric problem which boils down to the following parabolic equation: Suppose $u=u(r,t)$, $r$ is defined on $[0,1]$ and $t>0$ $$\begin{cases}\displaystyle \frac{\partial u}{\pa …
Slm2004's user avatar
  • 633
6 votes
1 answer
690 views

Derivation of yamabe flow

I am reading papers about yamabe flow. I have a problem about how people derive it as a gradient flow. Suppose we have $(M,g_0)$, $g(t)=u^{\frac{4}{n-2}}(t)g_0$ is another conformal metric. Let $R=R( …
Slm2004's user avatar
  • 633
1 vote
1 answer
171 views

metric has morse index 2

I am reading Richard Schoen's classical example on the multiplicity of solutions of yamabe problem. He says on $S^1(T)\times S^{n-1}$, there exists a critical number $T_0$ such that if $T\leq T_0$, th …
Slm2004's user avatar
  • 633
7 votes
1 answer
844 views

Reference for Hölder estimate on parabolic equation with Neumann boundary condition

I saw a type of Hölder estimate in Friedman's book: Partial Differential Equations of Parabolic Type (page 200, 3.24) which goes as follows: Suppose we have a uniformly parabolic equation with Hölder …
Slm2004's user avatar
  • 633
3 votes
0 answers
105 views

Boundedness of Calderon-Zygmund type operator

I am trying to prove the following fact. Suppose $\varphi\in C_c^\infty(\mathbb{R}^1)$. Define $$T(u)(x):=P.V.\int_{\mathbb{R}^1}\frac{\varphi(x)-\varphi(y)}{|x-y|^{\frac32}}u(y)dy$$ where P.V. means …
Slm2004's user avatar
  • 633
4 votes
0 answers
169 views

Inequality between Dirichlet and Neumann eigenvalue for Sturm Liouville problem

Consider the following Sturm Liouville problem on an interval $[a,b]$ $$\frac{\mathrm{d}}{\mathrm{d} x}\left[p(x) \frac{\mathrm{d} y}{\mathrm{d} x}\right]+q(x) y=-\lambda w(x) y$$ for given coefficie …
Slm2004's user avatar
  • 633
2 votes
1 answer
184 views

Boardline case of $W^{2,p}$ estimates on elliptic equations

Suppose $u$ is a strong solution of $$\begin{cases}\Delta u =f &\quad \text{in} \quad B_1(0)\\ u=0 &\quad \text{on}\quad \partial B_1\end{cases}$$ The well known $W^{2,p}$ estimates says if $f\in L^p( …
Slm2004's user avatar
  • 633
4 votes
1 answer
144 views

Boundedness of Riesz potential on Hardy space

I encounter the following claim in one paper: If $(-\Delta)^{\frac14}u\in L^{2,\infty}(\mathbb{R})$, then $u\in BMO(\mathbb{R})$. Equivalently in its dual version, if $u\in \mathcal{H}^1(\mathbb{R})$ …
Slm2004's user avatar
  • 633
7 votes
0 answers
3k views

Definition of homogeneous Sobolev spaces

As we know the inhomogeneous Sobolev space (we only consider $s>0$) $${H}^{s}\left(\mathbb{R}^{n}\right)=\left\{f \in L^2(\mathbb{R}^n):\int_{\mathbb{R}^{n}}|\xi|^{2 s}|\hat{f}(\xi)|^{2} \mathrm{d} \x …
Slm2004's user avatar
  • 633