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bio website math.vt.edu/people/renardym
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visits member for 4 years, 6 months
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May
21
comment Derivatives of radial functions can be bounded by derivatives in terms of radial distance?
This example does not quite seem to work. Does not $d^2f/dr^2$ get large when you actually do the modification near 0?
May
20
answered Interpolation between weighted $L^p$ spaces
May
20
reviewed Approve Formulating conditional constraints in optimization
May
13
reviewed Approve Loop space of manifold
May
10
comment Mixed (anisotropic) Sobolev spaces
The correct inference is that $f\in H^s(L^2)\cap L^2(H^s)$. You should look at the equivalent statement for Fourier transforms.
May
10
answered Mixed (anisotropic) Sobolev spaces
May
4
reviewed Approve oa.operator-algebras tag wiki excerpt
May
4
reviewed Approve riemannian-geometry tag wiki
May
4
awarded  Good Answer
May
4
reviewed Approve hilbert-manifolds tag wiki excerpt
May
4
reviewed Approve cauchy-schwarz-inequality tag wiki excerpt
May
4
reviewed Approve Singular projective variety where the Cartan homomorphism is not an isomorphism?
May
1
answered Fractional Sobolev spaces and interpolation in unbounded Lipschitz domains
May
1
answered Is the residual spectrum of every power bounded operator contained in the open unit disk?
Apr
29
comment Boundedness of heat semigroup on $L^1(\Omega)$
That is left as an exercise to the reader.
Apr
29
comment Boundedness of heat semigroup on $L^1(\Omega)$
This can be done on $C(\bar\Omega)$ by using the maximum principle and then on $L^1$ by duality. See for instance Theorem 3.10 in Pazy, Semigroups of Linear Operators and Applications to Partial Differential Equations.
Apr
28
comment Smallest degree of approximating polynomial
This is asked in a peculiar way. When you say $f(S_1)\in [1,1+2\epsilon]$, do you mean $f(S_1)\subset[1,1+2\epsilon]$ or that $f$ is constant on $S_1$ and its value lies in the interval?
Apr
28
comment Backward Uniqueness for the wave equation
But what if the boundary conditions are different? There are actually nontrivial problems (even unsolved problems) here. I doubt, however, that this is what the OP had in mind.
Apr
26
reviewed Edit A Question on 1, 2 ,3 Conjecture
Apr
26
revised A Question on 1, 2 ,3 Conjecture
minor grammar improvements