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Jan
6
comment Nonexistence of a certain norm on $C[0,1]$
Errr... why does $\|\cdot\|_\ast = \|\cdot\|_C$ not fulfill the assumption?
Dec
11
comment Tempered Distribution Calculation
Is there some Stieltjes-integral involved?
Dec
11
comment Stable and efficient projection onto subspace along another subspace
Actually, if I don't err, you do not even need to use Gram-Schmidth for $W$, as the new scalar product as constructed in the original post has been constructed to serve that way. Of course, we can normalize $w_i$ in advance with respect to that product, but that does not improve that substantially. (I think)
Dec
11
asked Stable and efficient projection onto subspace along another subspace
Dec
4
comment How can I compare unbounded linear operators?
Any bounded operator is called unbounded, too, which is completely common, isn't it?
Dec
3
asked How can I compare unbounded linear operators?
Dec
1
answered Projection operator and closed subspaces
Nov
30
revised Well-posedness of the Poisson problem with mixed boundary conditions
additional reference and motivation
Nov
27
comment Can you deduce Neumann boundary data from Dirichlet boundary data?
which, btw, tells about us that we cannot impose Neumann and Dirichlet boundary conditions simultaniously.
Nov
26
asked Well-posedness of the Poisson problem with mixed boundary conditions
Nov
16
awarded  Yearling
Nov
11
comment Can metric properties can be expressed in category theoretical terms?
@Rasmus: We indeed have this equivalence. But besides the algebraic statement, that the dualization functor is naturally equivalent to an endofunctor, I also would like to express in categorial terms that this equivalence holds. In contrast, the norm of the dual morphism could have no relation at all to the original morphism. Such a functor would be useless for analytic purposes.
Nov
11
asked Can metric properties can be expressed in category theoretical terms?
Nov
9
asked How strong does a matrix distort angles? How strong does it distort lengths anisotrolicly?
Oct
23
comment Are integrations on forms “different” from Riemann integrations?
Could you explain, why the Riemann integral is prefered over the Lebesgue integral in this case - or rather, why it is enforced by the structure of the theory?
Oct
19
comment Where do I fail with this integral (coordinates on a simplex)?
My goal is scheme for monomials on a simplex. If the polynomial is $x_1 x_2$, then you get a mixed expression $x_1(1-x_1)^2/2$, and substitution does not substantially change the expression. In case there is a better form for $x^k_1(1-x_1)^l$ in general, I am eager to know.
Oct
19
accepted Where do I fail with this integral (coordinates on a simplex)?
Oct
19
comment Where do I fail with this integral (coordinates on a simplex)?
thank you very much for pointing out this mistake. - This is, btw, motivated by an algorithm to compute integrals like the above, so there is more behind the question than just an oddity.
Oct
19
asked Where do I fail with this integral (coordinates on a simplex)?
Sep
28
comment Is -5 bigger than -1?
@anon: If you are 100 dollars in debt, while I am 1000 dollars in debt, who of us has "more debt"? The meaning of less and more depends on the direction you declare as ascending. - If you have a primitive economy, you may either have no gold nuggets at all, or a positive number of them, so "more" and "less" are meaningful concepts for abstract numbers. But if you introduce financial economy and invent debts, negative numbers become useful, but I think the meaning of numbers changes.