Surgery Approach to Rudyak's Conjecture

Surgery Applications to a Generalized Rudyak Conjecture

Rudyak's conjecture states that cat$(M) \geq$ cat$(N)$ given a degree one map $f:M \to N$ between closed manifolds. We generalize this conjecture to sectional category, and follow the methodology of [5] to get the following result: Given a normal map of degree one $f:M \to N$ between smooth closed manifolds, fibrations $p^M:E^M \to M$ and $p^N:E^N \to N$, and lift $\overline{f}$ of $f$ with respect to $p^M$ and $p^N$, i.e., $fp^M = \overline{f} p^N$; then if $f$ has no surgery obstructions and $N$ satisfies the inequality $5 \leq \dim N \leq 2r$ secat$(p^N) - 3$ (where the fiber of $p^N$ is $(…

Rudyak 的猜想对于低维 1 连通流形

Rudyak's conjecture for lower dimensional 1-connected manifolds

本文证明了Rudyak猜想在n维简单连通的spin流形中对于n≤8的情况成立，涉及范畴不等式及映射性质。

The LS-category of the product of lens spaces

We reduced Rudyak's conjecture that a degree one map between closed manifolds cannot raise the Lusternik-Schnirelmann category to the computation of the category of the product of two lens spaces $L^n_p\times L_q^n$ with relatively prime $p$ and $q$. We have computed $cat(L^n_p\times L^n_q)$ for values of $p,q>n/2$. It turns out that our computation supports the conjecture. For spin manifolds $M$ we establish a criterion for the equality $cat M=dim M-1$ which is a K-theoretic refinement of the Katz-Rudyak criterion for $cat M=dim M$. We apply it to obtain the inequality $cat(L^n_p\times L^n_q)…

闭 manifold 手术障碍和渗出猜想

Closed manifold surgery obstructions and the Oozing Conjecture

本文通过新例子反驳了渗出猜想，揭示了闭流形在高维中的非平凡手术障碍特性。

On Iwase's manifolds

In ~\cite{Iw2} Iwase has constructed two 16-dimensional manifolds $M_2$ and $M_3$ with LS-category 3 which are counter-examples to Ganea's conjecture: ${\rm cat_{LS}} (M\times S^n)={\rm cat_{LS}} M+1$. We show that the manifold $M_3$ is a counter-example to the logarithmic law for the LS-category of the square of a manifold: ${\rm cat_{LS}}(M\times M)=2{\rm cat_{LS}} M$. Also, we construct a map of degree one $$f:N\to M_2\times M_3$$ which reduces Rudyak's conjecture to the question whether ${\rm cat_{LS}}(M_2\times M_3)\ge 5$. We show that ${\rm cat_{LS}}(M_2\times M_3)\ge 4$.

Surgery On Foliations

In this paper, we set up two surgery theories and two kinds of Whitehead torsion for foliations. First, we construct a bounded surgery theory and bounded Whitehead torsion for foliations, which correspond to the Connes' foliation algebra in the K-theory of operator algebras, in the sense that there is an analogy between surgery theory and index theory, and a Novikov Conjecture for bounded surgery on foliations in analogy with the foliated Novikov conjecture of P.Baum and A.Connes in operator theory. This surgery theory classifies the leaves topologically. Secondly, we construct a bounded geome…