All Questions
Tagged with k3-surfaces at.algebraic-topology 
            
            3
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            66
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    Is there an octonionic analog of the K3 surface, with implications for stable homotopy groups of spheres?
                The infamous K3 surface has many constructions in many fields ranging from algebraic geometry to algebraic topology. Its many properties are well known. For this question I am really interested in the ...
            
        
       
    
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    Isotopy classes of $CP^1$ in 4-manifolds
                Let $S_1$, $S_2$ be homologous embedded 2-spheres
in a compact smooth 4-manifold. Under which additional
conditions are they smoothly isotopic? I am interested
in the state of the art picture when $...
            
        
       
    
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            1
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            371
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    Understand the Mukai vector
                Let $S$ be a K3 surface and $h:=c_1(i^*\mathcal{O}_{\mathbb{P^3}}(1))$, then we can compute that $c_1(S)=0,c_2(S)=6h^2$. Hence
\begin{align}
\sqrt{\text{td}(S)}=1+\frac{c_2(S)}{24}=1+\frac{1}{4}h^2
\...