Graph homomorphisms III: Models

نویسنده

  • Taoyang Wu
چکیده

Following the last talk on graph homomorphisms, we continue to discuss some examples of graph homomorphisms. But this time we will focus on some models, that is, the homomorphism G → H for the graph H with fixed weights. The main reference is Section 1 in [2].

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Counting Graph Homomorphisms

3 Connection matrices 9 3.1 The connection matrix of a graph parameter . . . . . . . . . . . . . . . . . . . . 9 3.2 The rank of connection matrices . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 3.3 Connection matrices of homomorphisms . . . . . . . . . . . . . . . . . . . . . . . 12 3.4 The exact rank of connection matrices for homomorphisms . . . . . . . . . . . . 13 3.5 Extensions...

متن کامل

From the Ising and Potts models to the general graph homomorphism polynomial

A graph homomorphism from a graph G to a graph H is a mapping h : V (G)→ V (H) such that h(u) ∼ h(v) if u ∼ v. Graph homomorphisms are well studied objects and, for suitable choices of eitherG orH, many classical graph properties can be formulated in terms of homomorphisms. For example the question of wether there exists a homomorphism from G to H = Kq is the same as asking wether G is q-colour...

متن کامل

Statement of David Galvin , July 31 , 2012

The main thrust of my research is the use of techniques from information theory, probability and combinatorics to study structural, enumerative and algorithmic aspects of graph homomorphisms and related models, both in particular instances (independent sets and colorings, for example) and in general. Graph homomorphisms are important objects in graph theory, where they generalize a number of ce...

متن کامل

Edge-reflection positivity and weighted graph homomorphisms

B. Szegedy [Edge coloring models and reflection positivity, Journal of the American Mathematical Society 20 (2007) 969–988] showed that the number of homomorphisms into a weighted graph is equal to the partition function of a complex edge-coloring model. Using some results in geometric invariant theory, we characterize for which weighted graphs the edge-coloring model can be taken to be real va...

متن کامل

Graph Labelings Derived from Models in Distributed Computing

We discuss 11 known basic models of distributed computing: four message-passing models that differ by the (non)existence of port-numbers and a hierarchy of seven local computations models. In each of these models, we study the computational complexity of the decision problems if the leader election and if the naming problem can be solved on a given network. It is already known that these two de...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:

دوره   شماره 

صفحات  -

تاریخ انتشار 2006