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Apr 13, 2017 at 12:19 history edited CommunityBot
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S Mar 16, 2015 at 16:02 history suggested Hachino CC BY-SA 3.0
Improved formatting overall, corrected typos here and there.
Mar 16, 2015 at 15:57 review Suggested edits
S Mar 16, 2015 at 16:02
Mar 16, 2015 at 15:46 review Close votes
Mar 16, 2015 at 17:01
Mar 15, 2015 at 11:06 answer added Hachino timeline score: 1
Mar 15, 2015 at 10:17 comment added Hachino Give me a few minutes, I was going to do so anyway.
Mar 15, 2015 at 10:16 comment added Learner @Hachino I would be glad if you could check my calculations and some further guidance .
Mar 15, 2015 at 10:00 comment added Learner @Hachino Yes, my main objective is to understand the variations of EV/EF's wrt the domain and shape optimisation .
Mar 15, 2015 at 9:53 comment added Hachino Btw, your notations and computations suggest that you are trying to understand variations of eigenvalues/eigenfunctions w.r.t. the underlying domain and shape optimization. Is it so ?
Mar 15, 2015 at 9:51 comment added Hachino Your definition of $\lambda(\Omega_t) := \mathbf{min} \{R(v, \Omega_t) : v \in H^{1,2}(\Omega_t)\}$ implies that 1) $\lambda$ is nonnegative 2) any constant, nonzero function achieves a zero value for the Rayleigh quotient, which means that $\lambda = 0$. But under an additional condition, for instance $\lambda(\Omega_t) := \mathbf{min} \{R(v, \Omega_t) : v \in H^{1,2}(\Omega_t), \int_{\Omega_t} v = 0\}$ (or more generally, that your $v$'s are orthogonal to some subset of eigenfunctions of the Neumann laplacian on $\Omega_t$), $\lambda$ acquires a nontrivial value.
Mar 15, 2015 at 9:46 comment added Learner @Hachino Sir, The curious factor $\mu(u)$ does appear because of the differentiation of $\left(\int_{\Omega_t }(u+s\varphi)^q\right)^{2/q}$ w.r.t $s$ . I do not understand what orthogonality condition you mean . I would be glad if you could elaborate it for me .
Mar 15, 2015 at 9:33 comment added Hachino I would have two things to point out : first, if you set $\alpha = 0$ and $q=2$, your final equations are the same as in the first case, apart from this curious $\mu(u)$, which probably shouldn't be there. Secondly, you forgot to add orthogonality conditions in both cases, in the spirit of $\int_{\Omega_t} u = 0$. Otherwise, non zero constant functions are obvious global minimizers.
Mar 15, 2015 at 9:00 review First posts
Mar 15, 2015 at 9:17
Mar 15, 2015 at 8:58 history asked Learner CC BY-SA 3.0