1,735 reputation
627
bio website www-ian.math.uni-magdeburg.de/…
location Magdeburg, Germany
age 31
visits member for 3 years, 7 months
seen Jul 16 at 0:38

I am an Australian mathematician.


May
31
answered evolution of curvature under ricci flow , What does the tensor A*B means?
May
30
answered differential and arc length notation question
Mar
23
comment Does every closed curve contain the vertices of a square?
The question is essentially settled for $C^2$ curves, locally graphical curves if we restrict ourselves to one codimension. There is still more to be done (rectifiable curves would be interesting).
Mar
23
comment How to prove convex+concave=affine?
@breezeintopl Click the green checkmark near the voting controls.
Mar
7
comment How to show given PDE preserves length while evolving curve to circle?
@Willie Right, while I would say showing that length is preserved is elementary, showing the parabolic regularity and global existence is not. (The classification of the limit is likely again elementary, like you say.)
Mar
7
comment Where does the mass disappear in Fatou's Lemma?
@Shyam I (personally) visualise a sequence of functions as being time-slices from some abstract energy-minimising evolution equation. Relaxation is just a synonym for taking a limit of these time-slices, and is a reduction of energy ('Excitation' being the opposite). Relaxation doesn't always give an equilibrium. In the sense it is used here, it is just a synonym for taking a limit.
Mar
7
answered How to show given PDE preserves length while evolving curve to circle?
Mar
7
answered Calabi flow and Robinson - Trautman equation
Mar
7
answered Where does the mass disappear in Fatou's Lemma?
Feb
10
accepted Nonlinear Fubini-Tonelli?
Jan
12
awarded  Nice Question
Dec
2
awarded  Yearling
Sep
2
awarded  Revival
Aug
31
answered Calculating the area of a special hexagon
Aug
26
comment The integral of the mean curvature vector over a closed immersed surface
Thanks for the reply. I'll have to think a bit more before I can digest this fully.
Aug
26
accepted The integral of the mean curvature vector over a closed immersed surface
Aug
26
comment The integral of the mean curvature vector over a closed immersed surface
Hi Willie, thanks for the answer. Could you elaborate a little more on why there is no canonical vector space in which the mean curvature of a submanifold lives? I would have naively thought the Euclidean analogue works under mild conditions on the ambient space.
Aug
25
comment The integral of the mean curvature vector over a closed immersed surface
@Theo Thanks for the summary. Exact components in which basis, the standard Euclidean basis? I didn't think of trying that. The generalisation you mention really answers the question I have posed.
Aug
25
revised The integral of the mean curvature vector over a closed immersed surface
clarification
Aug
25
comment The integral of the mean curvature vector over a closed immersed surface
@Willie I meant by this that $\Sigma$ has a Riemannian structure induced by $f$. I shall make it more explicit.