We investigate a new class of codes for the optimal covering of vertices in an undirected graphG such that any vertex in G can be uniquely identified by examining the vertices that cover it. Weâ€¦ (More)

Ethernet networks rely on the so-called spanning tree protocol (IEEE 802.1d) in order to break cycles, thereby avoiding the possibility of infinitely circulating packets and deadlocks. This protocolâ€¦ (More)

We discuss the problem of counting the maximum number of distinct states that an isolated physical system can pass through in a given period of time its maximum speed of dynamical evolution. Previousâ€¦ (More)

A subset C of vertices in an undirected graph G=(V,E) is called a 1-identifying code if the sets I(v)={u/spl isin/C:d(u,v)/spl les/1}, v/spl isin/V, are nonempty and no two of them are the same set.â€¦ (More)

Ethernet networks rely on the so-called spanning tree protocol (IEEE 802.1d) in order to break cycles, thereby avoiding the possibility of infinitely circulating packets and deadlocks. This protocolâ€¦ (More)

We consider a quantum gate that complements the state of a qubit and then adds to it an arbitrary phase shift. It is shown that the minimum operation time of the gate is Ï„ = h 4E (1+2 Î¸ Ï€), where hâ€¦ (More)

We consider the problem of data reconciliation, which we model as two separate multisets of data that must be reconciled with minimum communication. Under this model, we show that the problem ofâ€¦ (More)

How fast a quantum state can evolve has attracted considerable attention in connection with quantum measurement and information processing. A lower bound on the orthogonalization time, based on theâ€¦ (More)