论文标题
列表协议扩展从共扩展中扩展
List Agreement Expansion from Coboundary Expansion
论文作者
论文摘要
PCP结构中的关键组成部分之一是协议测试。在协议测试中,测试仪可以访问某些集合的固定大小的子集,每个子集配备了分配。然后,测试仪的任务是测试这些本地任务是否与整个集合中的某些全局分配一致。该概念的一种自然概括是,在每个局部视图中,不是对每个本地视图的单个分配,而是为每个子集提供了$ l $不同的分配。然后,测试仪的任务是测试是否存在$ l $ global功能,这些功能与所有本地视图的所有作业一致。 在这项工作中,我们为设定系统提供了足够的条件,可以展示列表协议扩展的广义定义。据我们所知,这是考虑协议测试的这种自然概括的第一项工作。尽管最初看起来与协议扩展非常相似,但列表协议的扩展似乎需要不同的技术。这是由于以下事实:在测试列表协议时,一致性测试的自然扩展不足以依赖于全球结构的列表协议。因此,如果本地任务满足清单协议,他们不仅必须在本地同意,还必须表现出一些额外的结构。为了测试这种附加结构的存在,我们使用覆盖高尺寸复合物及其串联的空间之间的连接。我们将此连接用作``脱钩''的一种形式。 此外,我们表明,任何展示列表协议扩展的设置系统也支持直接总和测试。这是第一个直接总和测试的方案,无论本地集合的均等均等,都可以使用。在我们的工作之前,直接总和测试方案基于本地测试大小的奇偶校验。
One of the key components in PCP constructions are agreement tests. In agreement test the tester is given access to subsets of fixed size of some set, each equipped with an assignment. The tester is then tasked with testing whether these local assignments agree with some global assignment over the entire set. One natural generalization of this concept is the case where, instead of a single assignment to each local view, the tester is given access to $l$ different assignments for every subset. The tester is then tasked with testing whether there exist $l$ global functions that agree with all of the assignments of all of the local views. In this work we present sufficient condition for a set system to exhibit this generalized definition of list agreement expansion. This is, to our knowledge, the first work to consider this natural generalization of agreement testing. Despite initially appearing very similar to agreement expansion, list agreement expansion seem to require a different set of techniques. This is due to the fact that the natural extension of agreement testing does not suffice when testing for list agreement, as list agreement crucially relies on a global structure. It follows that if a local assignments satisfy list agreement they must not only agree locally but also exhibit some additional structure. In order to test for the existence of this additional structure we use a connection between covering spaces of a high dimensional complex and its coboundaries. We use this connection as a form of ``decoupling''. Moreover, we show that any set system that exhibits list agreement expansion also supports direct sum testing. This is the first scheme for direct sum testing that works regardless of the parity of the sizes of the local sets. Prior to our work the schemes for direct sum testing were based on the parity of the sizes of the local tests.