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bio website www-ian.math.uni-magdeburg.de/…
location Magdeburg, Germany
age 31
visits member for 3 years, 9 months
seen 7 hours ago

I am an Australian mathematician.


Jun
4
comment differential and arc length notation question
@soup This is totally standard when we take as a measure something induced by the map we are studying. You can see this same computation coming up in the first variation of the area element. I'm not sure what you mean by transport theorem.
May
31
comment Usage of the word “formal(ly)”
This is just an English language quirk. There are two basic meanings of 'formal' -- something related to 'form', which is not what you have in mind (despite being what Jazwinksi has in mind), and being rigorous. Mathematicians typically use the word rigorous when they mean rigorous.
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.