Please answer the following question: Information: - Paul Chester Kainen is an American mathematician , an adjunct associate professor of mathematics and director of the Lab for Visual Mathematics at Georgetown University . Kainen is the author of a popular book on the four color theorem , and is also known for his work on book embeddings of graphs . - Georgetown University is a private research university in Washington, D.C., the capital of the United States. Founded in 1789 as Georgetown College, the university has since grown to incorporate nine undergraduate and graduate schools, including the School of Foreign Service, School of Business, a Medical Center and a Law School. Georgetown's main campus is located on a hill above the Potomac River. It is recognizable by its flagship Healy Hall, a National Historic Landmark that towers over Washington's Georgetown neighborhood. - The Edmund A. Walsh School of Foreign Service (commonly abbreviated as SFS) is a school of international affairs within Georgetown University in Washington, D.C.. Recognized as one of the world's leading international relations schools, SFS is sometimes referred to as the "West Point of the U.S. diplomatic corps" due to the large number of SFS graduates who end up being diplomats. Founded in 1919, SFS predates the U.S. Foreign Service by six years. - In mathematics, a theorem is a statement that has been proved on the basis of previously established statements, such as other theoremsand generally accepted statements, such as axioms. A theorem is a logical consequence of the axioms. The proof of a mathematical theorem is a logical argument for the theorem statement given in accord with the rules of a deductive system. The proof of a theorem is often interpreted as justification of the truth of the theorem statement. In light of the requirement that theorems be proved, the concept of a theorem is fundamentally "deductive", in contrast to the notion of a scientific law, which is "experimental". - In mathematics, the four color theorem, or the four color map theorem, states that, given any separation of a plane into contiguous regions, producing a figure called a "map", no more than four colors are required to color the regions of the map so that no two adjacent regions have the same color. Two regions are called "adjacent" if they share a common boundary that is not a corner, where corners are the points shared by three or more regions. - In graph theory, a book embedding is a generalization of planar embedding of a graph to embeddings into a "book", a collection of half-planes all having the same line as their boundary. Usually, the vertices of the graph are required to lie on this boundary line, called the "spine", and the edges are required to stay within a single half-plane. The book thickness of a graph is the smallest possible number of half-planes for any book embedding of the graph. Book thickness is also called pagenumber, stacknumber or fixed outerthickness. Book embeddings have also been used to define several other graph invariants including the pagewidth and book crossing number. - Healy Hall is a National Historic Landmark located at the main campus of Georgetown University. Constructed between 1877-79, the hall was designed by Paul J. Pelz and John L. Smithmeyer, prominent architects who also built the Library of Congress. The structure was named after Patrick Francis Healy, who was the President of Georgetown University at the time. - A research university is a university that expects all its tenured and tenure-track faculty to continuously engage in research, as opposed to merely requiring it as a condition of an initial appointment or tenure. Such universities can be recognized by their strong focus on innovative research and the prestige of their brand names. On the one hand, research universities strive to recruit faculty who are the most brilliant minds in their disciplines in the world, and their students enjoy the opportunity to learn from such experts. On the other hand, new students are often disappointed to realize their undergraduate courses at research universities are overly academic and fail to provide vocational training with immediate "real world" applications; but many employers value degrees from research universities because they know that such coursework develops fundamental skills like critical thinking. - Mathematics (from Greek "mathma", knowledge, study, learning) is the study of topics such as quantity (numbers), structure, space, and change. There is a range of views among mathematicians and philosophers as to the exact scope and definition of mathematics. - The Potomac River is located along the mid-Atlantic Ocean coast of the United States and flows into the Chesapeake Bay. The river (main stem and North Branch) is approximately long, with a drainage area of about 14,700 square miles (38,000km). In terms of area, this makes the Potomac River the fourth largest river along the Atlantic coast of the United States and the 21st largest in the United States. Over 5 million people live within the Potomac watershed. What is the relationship between 'paul chester kainen' and 'graph theory'?
A:
field of work