9 votes
Accepted

Bull's-eye Riemann sum

Not necessarily. Take small $\delta>0$. Spend time $\frac 23(1-\delta)$ at $(0,1)$. Then, in time $\delta/4$ travel the route $(0,1)\to(0,2)\to(-1,2)\to(-1,-2)$ so that the integral of the vertical ...
fedja's user avatar
  • 59.8k
5 votes
Accepted

How to understand the integral?

If I understand your question correctly, the answer is affirmative for Ricci-flat (i.e. flat) surfaces (not necessarily embedded in a Euclidean space) according to equation (14) of Reilly, Robert C., ...
Terry Tao's user avatar
  • 109k
5 votes

Extending a convex function to a higher dimensional domain

Yes: Just take $u(x,y):=v(x)$, which will be assumed in what follows. Indeed, one can use Green's formula to show this, as is done in Christian Remling's answer. More generally, the result holds for ...
Iosif Pinelis's user avatar
4 votes

Extending a convex function to a higher dimensional domain

$u(x,y)=v(x)$ works. By Green's formula, we can rewrite the LHS of your inequality as $$ \frac{1}{2\pi} \int\!\!\!\int \Delta u\, dA = \frac{1}{2\pi}\int_{-1}^1 dy\int_{-\sqrt{1-y^2}}^{\sqrt{1-y^2}} ...
Christian Remling's user avatar
2 votes

Mean value theorem for Dirichlet series - optimize?

The following is an approach inspired by Selberg's treatment of the large sieve, and more directly by a sketch in Granville-Harper-Soundararajan (on the case of prime support). There remains an ...
H A Helfgott's user avatar
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1 vote
Accepted

Mean value theorem in terms of Wirtinger calculus?

The desired relation can be written in components as $$f_n(\mathbf{z}^{(1)},\mathbf{\bar z}^{(1)})-f_n(\mathbf{z}^{(2)},\mathbf{\bar z}^{(2)})=\int_0^1 d\tau\,\sum_{m}\left(\frac{\partial f_n}{\...
Carlo Beenakker's user avatar

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