论文标题
关于C* - 代数的异常对称的评论
Remarks on anomalous symmetries of C*-algebras
论文作者
论文摘要
对于组$ g $和$ g $和$ω\ in z^{3}(g,\ text {u}(1))$,在c*-algebra $ b $上进行的$ω$ - 反对动作是$ \ text {u}(u}(1)$ - 线性单线函数 - 2 groups $ \ text text text {2-group text {2-gr} {2-gr}(2-gr} {2-gr}(2-gr}(2-gr}(u})(2-gr}(2-gr}(U} u}(u} u}(2-gr), ω)\ rightarrow \ underline {\ text {aut}}(b)$,其中后者表示$*$ - $ b $的2组自动形态。类$ [ω] \ in H^{3}(g,\ text {u}(1))$称为动作的异常。我们显示每$ n \ ge 2 $和每个有限的组$ g $,每个异常都可以在稳定稳定的C*-Algebra $ c(m)\ otimes \ otimes \ Mathcal {k} $中,对于某些封闭的连接$ n $ -Manifold $ m $。我们还表明,尽管没有反对粗处的Roe C*代数异常的对称性,但对于每个有限的组$ G $,但在Roe Corona $ c^{*}(x)/\ Mathcal {k} $ a $ x $ a $ a $ a $ a $ a $ a $ a $ a $ a $ a $ a $ a $ a $ a $ a $ a $ a $ a $ a $ a $ a $ a $ a $ a $ a $ a $ a $ c $ a $ a。
For a group $G$ and $ω\in Z^{3}(G, \text{U}(1))$, an $ω$-anomalous action on a C*-algebra $B$ is a $\text{U}(1)$-linear monoidal functor between 2-groups $\text{2-Gr}(G, \text{U}(1), ω)\rightarrow \underline{\text{Aut}}(B)$, where the latter denotes the 2-group of $*$-automorphisms of $B$. The class $[ω]\in H^{3}(G, \text{U}(1))$ is called the anomaly of the action. We show for every $n\ge 2$ and every finite group $G$, every anomaly can be realized on the stabilization of a commutative C*-algebra $C(M)\otimes \mathcal{K}$ for some closed connected $n$-manifold $M$. We also show that although there are no anomalous symmetries of Roe C*-algebras of coarse spaces, for every finite group $G$, every anomaly can be realized on the Roe corona $C^{*}(X)/\mathcal{K}$ of some bounded geometry metric space $X$ with property $A$.