bio | website | perso-math.univ-mlv.fr/users/… |
---|---|---|
location | Paris, France | |
age | 35 | |
visits | member for | 5 years, 4 months |
seen | Jul 26 at 8:32 | |
stats | profile views | 3,441 |
I am a teacher and researcher at Université Paris-Est Créteil.
Jul 26 |
comment |
Computer calculations in a paper
I think your question is ambiguous. When you write "what kind of computer calculations can be included in a paper?", you may mean two different things: either you ask which computer assisted proofs can be considered as proofs, and make it into a published article; or you may ask what to write down explicitly in a paper reporting on such a proof. You may also want to ask both, but in any case you should make that clear. |
Jul 14 |
revised |
Measurability and Axiom of choice
Changed a "Borel" by a "Lebesgue". |
Jul 10 |
comment |
Mapping sphere surface to a vector space such that distances are preserved?
No, curvature is an obstruction (this settles the case of a $2$-dimensional target, but the for higher dimensions it suffices to consider a geodesic triangle which will be mapped to a $2$-dimensional subspace). I think this question belongs more to math.SE than to MO. |
Jun 29 |
comment |
Finite-space dynamical systems
Just to comment on the many interesting answers at once: it appears that this question has a kind of trivial feel at first (the dynamics converges to a cycle, how boring), but really sparkles when one has an additional structure on the state space: algebraic (finite fields), combinatorial (finite cellular automata) for example. Then the interaction between the additional structure and the dynamics seems to be very subtle. |
Jun 12 |
answered | Continuity of length and area |
Jun 10 |
comment |
Differentiability of polytope shadow areas
In fact, the same idea appears when one tries to make a Riemannian metric out of a Finsler metric by using the John ellipsoid, which is something I came across a few years ago. |
Jun 9 |
answered | Differentiability of polytope shadow areas |
Jun 4 |
comment |
Examples of Smooth, Compact and Non-rigid Manifolds that Bound a Finite, Non-zero Volume
@ManfredWeis: I took the liberty to precise the question: for abstract Riemannian manifolds, an isometric deformation is precisely changing nothing. |
Jun 4 |
revised |
Examples of Smooth, Compact and Non-rigid Manifolds that Bound a Finite, Non-zero Volume
precised the question in accordance with the comments. |
Jun 4 |
comment |
Examples of Smooth, Compact and Non-rigid Manifolds that Bound a Finite, Non-zero Volume
I don't understand what you mean by an isometric deformation; do you mean "submanifold of $\mathbb{R}^n$" when you say "manifold"? Given your title, do you further mean hypersurfaces? |
Jun 1 |
revised |
Simultaneous approximation of arbitrary functions in Hölder space and in $L^2(\mu)$ by a smooth function and its derivative
edited body |
May 27 |
comment |
Maximizing entropy under constraints
@VaughnClimenhaga: thanks for the clarification; in fact one of the nice point is that we are able to consider several constraints $\int \varphi_k \,d\mu=0$, which complicate things a bit as one needs more than the intermediate value theorem to get surjectivity. At the moment, it seems that the reference given by Anthony Quas is closest to what I asked, but the Barreira-Saussol thread will have to be mentioned. |
May 27 |
comment |
Maximizing entropy under constraints
@BarbaraSchapira: note that I chose a context (shift with Hölder potentials) where the existence of Gibbs measures and coincidence with equilibrium states is not an issue (unless we mean different things by Gibbs measure, which might be the case). Note also that I am asking about a constrained case, i.e. we restrict to measure satisfying a certain equality $\int \varphi \,d\mu=0$; I do not see how this is addressed by the usual equilibrium states. |
May 27 |
revised |
Simultaneous approximation of arbitrary functions in Hölder space and in $L^2(\mu)$ by a smooth function and its derivative
Made the title more accurate |
May 27 |
answered | Simultaneous approximation of arbitrary functions in Hölder space and in $L^2(\mu)$ by a smooth function and its derivative |
May 26 |
comment |
Maximizing entropy under constraints
Thanks for your detailed answer; I must say that a quick look at the references you mention did not enable me to find what I looked for: I found interpretation in terms of multifractal spectra of such maximization problems, but not the description of how a maximizing (Gibbs) measure can be found. But you warned about the fact that these are implicit, so I guess I just need to take a more careful look. |
May 25 |
comment |
Maximizing entropy under constraints
@AnthonyQuas: the pointer to Christian Wolf and Tamara Kucherenko is so good that it could be made an answer; it seems after a quick look that their work does contain this application of our work. Thanks! |
May 25 |
revised |
Simultaneous approximation of arbitrary functions in Hölder space and in $L^2(\mu)$ by a smooth function and its derivative
Corrected my guess to a less obviously flase one. |
May 25 |
comment |
Simultaneous approximation of arbitrary functions in Hölder space and in $L^2(\mu)$ by a smooth function and its derivative
@ChristianRemling: you are of course right. I will edit my guess. |
May 25 |
asked | Maximizing entropy under constraints |