Skip to main content
grammar
Source Link
Mike Usher
  • 2.9k
  • 15
  • 19

Unless I'm misunderstanding what you're asking, the answer is surely no...consider for instance $\mathbb{C}P^n$ with its standard symplectic and complex structures. This admits embedded J$J$-holomorphic curves of arbitraryarbitrarily large area (take a high-degree curve in a plane $\mathbb{C}P^2\subset \mathbb{C}P^n$), and restricting to a disc within any of these curves would give you a $J$-holomorphic disc u$u$ of arbitraryarbitrarily large area (which I assume is what you mean by the symplectic volume of u$u$).

On more general symplectic manifolds $(M,\omega)$, the h-principle gives you immersed symplectic spheres in every homology class $A$ with $\int_{A}\omega>0$; these spheres can be taken embedded if $\dim M\geq 6$ and embedded away from finitely many transverse double points if $\dim M=4$. In either case you could construct an almost complex structure $J$ on $M$ with respect to which an arbitrarily large-area subdisk of the surface is embedded and $J$-holomorphic. (This is admittedly a little weaker than the first example, since here we're choosing $J$ after we choose the surface--so all it shows is that for any $C$ there is a pair $(u,J)$ where $u$ is a $J$-holomorphic disc of area larger than $C$, with $J$ possibly depending on $C$.)

Unless I'm misunderstanding what you're asking, the answer is surely no...consider for instance $\mathbb{C}P^n$ with its standard symplectic and complex structures. This admits embedded J-holomorphic curves of arbitrary large area (take a high-degree curve in a plane $\mathbb{C}P^2\subset \mathbb{C}P^n$), and restricting to a disc within any of these curves would give you a $J$-holomorphic disc u of arbitrary large area (which I assume is what you mean by the symplectic volume of u).

On more general symplectic manifolds $(M,\omega)$, the h-principle gives you immersed symplectic spheres in every homology class $A$ with $\int_{A}\omega>0$; these spheres can be taken embedded if $\dim M\geq 6$ and embedded away from finitely many transverse double points if $\dim M=4$. In either case you could construct an almost complex structure $J$ on $M$ with respect to which an arbitrarily large-area subdisk of the surface is embedded and $J$-holomorphic. (This is admittedly a little weaker than the first example, since here we're choosing $J$ after we choose the surface--so all it shows is that for any $C$ there is a pair $(u,J)$ where $u$ is a $J$-holomorphic disc of area larger than $C$, with $J$ possibly depending on $C$.)

Unless I'm misunderstanding what you're asking, the answer is surely no...consider for instance $\mathbb{C}P^n$ with its standard symplectic and complex structures. This admits embedded $J$-holomorphic curves of arbitrarily large area (take a high-degree curve in a plane $\mathbb{C}P^2\subset \mathbb{C}P^n$), and restricting to a disc within any of these curves would give you a $J$-holomorphic disc $u$ of arbitrarily large area (which I assume is what you mean by the symplectic volume of $u$).

On more general symplectic manifolds $(M,\omega)$, the h-principle gives you immersed symplectic spheres in every homology class $A$ with $\int_{A}\omega>0$; these spheres can be taken embedded if $\dim M\geq 6$ and embedded away from finitely many transverse double points if $\dim M=4$. In either case you could construct an almost complex structure $J$ on $M$ with respect to which an arbitrarily large-area subdisk of the surface is embedded and $J$-holomorphic. (This is admittedly a little weaker than the first example, since here we're choosing $J$ after we choose the surface--so all it shows is that for any $C$ there is a pair $(u,J)$ where $u$ is a $J$-holomorphic disc of area larger than $C$, with $J$ possibly depending on $C$.)

Source Link
Mike Usher
  • 2.9k
  • 15
  • 19

Unless I'm misunderstanding what you're asking, the answer is surely no...consider for instance $\mathbb{C}P^n$ with its standard symplectic and complex structures. This admits embedded J-holomorphic curves of arbitrary large area (take a high-degree curve in a plane $\mathbb{C}P^2\subset \mathbb{C}P^n$), and restricting to a disc within any of these curves would give you a $J$-holomorphic disc u of arbitrary large area (which I assume is what you mean by the symplectic volume of u).

On more general symplectic manifolds $(M,\omega)$, the h-principle gives you immersed symplectic spheres in every homology class $A$ with $\int_{A}\omega>0$; these spheres can be taken embedded if $\dim M\geq 6$ and embedded away from finitely many transverse double points if $\dim M=4$. In either case you could construct an almost complex structure $J$ on $M$ with respect to which an arbitrarily large-area subdisk of the surface is embedded and $J$-holomorphic. (This is admittedly a little weaker than the first example, since here we're choosing $J$ after we choose the surface--so all it shows is that for any $C$ there is a pair $(u,J)$ where $u$ is a $J$-holomorphic disc of area larger than $C$, with $J$ possibly depending on $C$.)