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C. Peskine and L. Szpiro in "Dimension projective finie et cohomologie locale",(Proposition 4.1) proved the following vanishing theorem for local cohomology: Let$R$ be a regular local ring of characteristic $p\gneqq 0$. Let $I$ be an ideal of $R$ such that $R/I$ is a CM(i.e. Cohen-Macaulay) ring; then: $$H_I^i(M) = 0~~ \text{for each}~ i> \text{dim} R-\text{dim} R/I.$$ It is to be noted that this theorem does not extend to characteristic $0$.

But I think to a restricted version, when the characteristic is zero. My question is that if $R= K [[ x_1, x_2, ...x_n]]$, where $K$ is a field with $\text{char}~K=0$ and $R/I$ is a CM ring, is it true that: $$\text{inj}~\text{dim}~H_I^i(R) =\text{dim}~ H_I^i(R)? $$

But I think to a restricted version, whenMichael Hellus in http://arxiv.org/pdf/math/0703126v1.pdf has attacked the characteristic is zero. My question is that if $R= K [[ x_1, x_2, ...x_n]]$, whereand in this case has established the following facts:

Let $K$ is$R$ be a noetherian local regular ring containing a field with, $\text{char}~K=0$$I$ an ideal of $R$ and $R/I$ is$i$ a CM ring,natural number. Here is it true thata summary of results:

(i) If $H^i_I(R)$ is $I$-cofinite then $\text{inj dim} _R(H^i_I(R))=\dim _R(H^i_I(R))$ holds.

(ii) There are examples where $H^i_I(R)$ is not $I$-cofinite, but $$\text{inj}~\text{dim}~H_I^i(R) =\text{dim}~ H_I^i(R)? $$$\text{inj dim} _R(H^i_I(R))=\dim _R(H^i_I(R))$ holds.

(iii) There are examples where $\text{inj dim} _R(H^i_I(R))=\dim _R(H^i_I(R))$ does not hold.

C. Peskine and L. Szpiro in "Dimension projective finie et cohomologie locale",(Proposition 4.1) proved the following vanishing theorem for local cohomology: Let$R$ be a regular local ring of characteristic $p\gneqq 0$. Let $I$ be an ideal of $R$ such that $R/I$ is a CM(i.e. Cohen-Macaulay) ring; then: $$H_I^i(M) = 0~~ \text{for each}~ i> \text{dim} R-\text{dim} R/I.$$ It is to be noted that this theorem does not extend to characteristic $0$.

But I think to a restricted version, when the characteristic is zero. My question is that if $R= K [[ x_1, x_2, ...x_n]]$, where $K$ is a field with $\text{char}~K=0$ and $R/I$ is a CM ring, is it true that: $$\text{inj}~\text{dim}~H_I^i(R) =\text{dim}~ H_I^i(R)? $$

C. Peskine and L. Szpiro in "Dimension projective finie et cohomologie locale",(Proposition 4.1) proved the following vanishing theorem for local cohomology: Let$R$ be a regular local ring of characteristic $p\gneqq 0$. Let $I$ be an ideal of $R$ such that $R/I$ is a CM(i.e. Cohen-Macaulay) ring; then: $$H_I^i(M) = 0~~ \text{for each}~ i> \text{dim} R-\text{dim} R/I.$$ It is to be noted that this theorem does not extend to characteristic $0$.

But I think to a restricted version, when the characteristic is zero. My question is that if $R= K [[ x_1, x_2, ...x_n]]$, where $K$ is a field with $\text{char}~K=0$ and $R/I$ is a CM ring, is it true that: $$\text{inj}~\text{dim}~H_I^i(R) =\text{dim}~ H_I^i(R)? $$

Michael Hellus in http://arxiv.org/pdf/math/0703126v1.pdf has attacked the question and in this case has established the following facts:

Let $R$ be a noetherian local regular ring containing a field, $I$ an ideal of $R$ and $i$ a natural number. Here is a summary of results:

(i) If $H^i_I(R)$ is $I$-cofinite then $\text{inj dim} _R(H^i_I(R))=\dim _R(H^i_I(R))$ holds.

(ii) There are examples where $H^i_I(R)$ is not $I$-cofinite, but $\text{inj dim} _R(H^i_I(R))=\dim _R(H^i_I(R))$ holds.

(iii) There are examples where $\text{inj dim} _R(H^i_I(R))=\dim _R(H^i_I(R))$ does not hold.

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A version of Peskine and Szpiro's theorem in vanishing of local cohomology

C. Peskine and L. Szpiro in "Dimension projective finie et cohomologie locale",(Proposition 4.1) proved the following vanishing theorem for local cohomology: Let$R$ be a regular local ring of characteristic $p\gneqq 0$. Let $I$ be an ideal of $R$ such that $R/I$ is a CM(i.e. Cohen-Macaulay) ring; then: $$H_I^i(M) = 0~~ \text{for each}~ i> \text{dim} R-\text{dim} R/I.$$ It is to be noted that this theorem does not extend to characteristic $0$.

But I think to a restricted version, when the characteristic is zero. My question is that if $R= K [[ x_1, x_2, ...x_n]]$, where $K$ is a field with $\text{char}~K=0$ and $R/I$ is a CM ring, is it true that: $$\text{inj}~\text{dim}~H_I^i(R) =\text{dim}~ H_I^i(R)? $$