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Francesco Polizzi
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The answer is yes. In fact, there is the following

Proposition 1. Every $2$-dimensional rational singularity $(X, \, x)$ is analytically $\mathbb{Q}$-factorial, i.e. there exists an analytic neighborhood $V$ of $x$ such that every Weil divisor on $V$ is a $\mathbb{Q}$-Cartier divisor.

In particular, every $2$-dimensional rational singularity is $\mathbb{Q}$-Gorenstein.

Concerning the particular case of rational Gorenstein singularities, we have

Proposition 2. For a $2$-dimensional normal singularity $(X, \, x)$, the following are equivalent:

  1. $(X, \, x)$ is a rational double point (i.e., a Du Val singularity);
  2. $(X, \, x)$ is a rational hypersurface singularity;
  3. $(X, \, x)$ is a rational Gorenstein singularity;
  4. $(X, \, x)$ is a canonical singularity.

See S. Ishii, Introduction to Singularities, Theorem 7.3.2 and Theorem 7.5.1.

The answer is yes. In fact, there is the following

Proposition. Every $2$-dimensional rational singularity $(X, \, x)$ is analytically $\mathbb{Q}$-factorial, i.e. there exists an analytic neighborhood $V$ of $x$ such that every Weil divisor on $V$ is a $\mathbb{Q}$-Cartier divisor.

In particular, every $2$-dimensional rational singularity is $\mathbb{Q}$-Gorenstein.

See S. Ishii, Introduction to Singularities, Theorem 7.3.2.

The answer is yes. In fact, there is the following

Proposition 1. Every $2$-dimensional rational singularity $(X, \, x)$ is analytically $\mathbb{Q}$-factorial, i.e. there exists an analytic neighborhood $V$ of $x$ such that every Weil divisor on $V$ is a $\mathbb{Q}$-Cartier divisor.

In particular, every $2$-dimensional rational singularity is $\mathbb{Q}$-Gorenstein.

Concerning the particular case of rational Gorenstein singularities, we have

Proposition 2. For a $2$-dimensional normal singularity $(X, \, x)$, the following are equivalent:

  1. $(X, \, x)$ is a rational double point (i.e., a Du Val singularity);
  2. $(X, \, x)$ is a rational hypersurface singularity;
  3. $(X, \, x)$ is a rational Gorenstein singularity;
  4. $(X, \, x)$ is a canonical singularity.

See S. Ishii, Introduction to Singularities, Theorem 7.3.2 and Theorem 7.5.1.

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Francesco Polizzi
  • 66.3k
  • 5
  • 180
  • 283

The answer is yes. In fact, there is the following

Proposition. Every $2$-dimensional rational singularity $(X, \, x)$ is analytically $\mathbb{Q}$-factorial, ini.e. there exists an analytic neighborhood $V$ of $x$ such that every Weil divisor on $V$ is a $\mathbb{Q}$-Cartier divisor.

In particular, every $2$-dimensional rational singularity is $\mathbb{Q}$-Gorenstein.

See S. Ishii, Introduction to SingularitiesIntroduction to Singularities, Theorem 7.3.2.

The answer is yes. In fact, there is the following

Proposition. Every $2$-dimensional rational singularity is analytically $\mathbb{Q}$-factorial, in particular $\mathbb{Q}$-Gorenstein.

See S. Ishii, Introduction to Singularities, Theorem 7.3.2.

The answer is yes. In fact, there is the following

Proposition. Every $2$-dimensional rational singularity $(X, \, x)$ is analytically $\mathbb{Q}$-factorial, i.e. there exists an analytic neighborhood $V$ of $x$ such that every Weil divisor on $V$ is a $\mathbb{Q}$-Cartier divisor.

In particular, every $2$-dimensional rational singularity is $\mathbb{Q}$-Gorenstein.

See S. Ishii, Introduction to Singularities, Theorem 7.3.2.

Source Link
Francesco Polizzi
  • 66.3k
  • 5
  • 180
  • 283

The answer is yes. In fact, there is the following

Proposition. Every $2$-dimensional rational singularity is analytically $\mathbb{Q}$-factorial, in particular $\mathbb{Q}$-Gorenstein.

See S. Ishii, Introduction to Singularities, Theorem 7.3.2.