In 1965 Anang Z. Gani [28] did research on the Facilities Planning problem as a special project at Georgia Tech under supervision of James Apple. The research was entitled “Evaluation of Alternative Materials Handling Pattern”. Later, J. M. Devis and K. M. Klein further continued the original work of Anang Z. Gani to develop the model and the computer program for Facilities Design and Layout. Then M. P. Deisenroth improved and finalized in 1971 under the name “PLANET” (Plant Layout Analysis and Evaluation Technique) under direction of James Apple (Georgia Tech) [2].

Since 1966, Anang Z. Gani has been continuing his research and further developed a new concept which is called “The Interaction Theory” for solving TSP in Bandung Institute of Technology (Indonesia). The basic concept of the Interaction Theory is to define a set of priorities for the interacting elements of a system to obtain the optimum solution for decision making.

Early research of the Interaction Theory resulted in the development of the model representing the flow of materials. The model is in the ‘From – To’ chart which provides quantitative information of the movement between departments. This chart is similar to the common mileage chart on the road map. In the case of the TSP, it is known as the distance matrix which comes from a set of point coordinates. In general, a matrix has a compact notation for describing sets of data and efficient methods for manipulating sets of data. The numbers that appear in the rows and columns of a matrix are called elements of the matrix.

The absolute value of a single element in a matrix cannot be used for priority setting, because it stands alone and does not have interaction with other elements. The priority of an element can be increase or decrease depending on the absolute value of its surroundings, which are the element in the same row and column. This value is called the relative value or the value of the interaction coefficient. Therefore, the TSP matrix has two values, namely the initial absolute value (interaction value) and the relative value (interaction coefficient),

In 2000, the Clay Foundation announced a historic competition: whoever could solve any of seven extraordinarily difficult mathematical problems, and have the solution acknowledged as correct by the experts, would receive $1 million in prize money. There was some precedent for doing this: In 1900 the mathematician David Hilbert proposed twenty-three problems that set much of the agenda for mathematics in the twentieth century. The Millennium Problems--chosen by a committee of the leading mathematicians in the world--are likely to acquire similar stature, and their solution (or lack of it) is likely to play a strong role in determining the course of mathematics in the twenty-first century. Keith Devlin, renowned expositor of mathematics and one of the authors of the Clay Institute's official description of the problems, here provides the definitive account for the mathematically interested reader. In 2003, he launched a book entitled "The Millenium Problems" .

As of October 2014, six of the problems remain unsolved. P versus NP is one of the seven problems since most mathematicians and computer scientists expect that P ≠ NP. This Interaction Theory is attempting to solve this particular problem.

Since 1966, Anang Z. Gani has been continuing his research and further developed a new concept which is called “The Interaction Theory” for solving TSP in Bandung Institute of Technology (Indonesia). The basic concept of the Interaction Theory is to define a set of priorities for the interacting elements of a system to obtain the optimum solution for decision making.

Early research of the Interaction Theory resulted in the development of the model representing the flow of materials. The model is in the ‘From – To’ chart which provides quantitative information of the movement between departments. This chart is similar to the common mileage chart on the road map. In the case of the TSP, it is known as the distance matrix which comes from a set of point coordinates. In general, a matrix has a compact notation for describing sets of data and efficient methods for manipulating sets of data. The numbers that appear in the rows and columns of a matrix are called elements of the matrix.

The absolute value of a single element in a matrix cannot be used for priority setting, because it stands alone and does not have interaction with other elements. The priority of an element can be increase or decrease depending on the absolute value of its surroundings, which are the element in the same row and column. This value is called the relative value or the value of the interaction coefficient. Therefore, the TSP matrix has two values, namely the initial absolute value (interaction value) and the relative value (interaction coefficient),

In 2000, the Clay Foundation announced a historic competition: whoever could solve any of seven extraordinarily difficult mathematical problems, and have the solution acknowledged as correct by the experts, would receive $1 million in prize money. There was some precedent for doing this: In 1900 the mathematician David Hilbert proposed twenty-three problems that set much of the agenda for mathematics in the twentieth century. The Millennium Problems--chosen by a committee of the leading mathematicians in the world--are likely to acquire similar stature, and their solution (or lack of it) is likely to play a strong role in determining the course of mathematics in the twenty-first century. Keith Devlin, renowned expositor of mathematics and one of the authors of the Clay Institute's official description of the problems, here provides the definitive account for the mathematically interested reader. In 2003, he launched a book entitled "The Millenium Problems" .

As of October 2014, six of the problems remain unsolved. P versus NP is one of the seven problems since most mathematicians and computer scientists expect that P ≠ NP. This Interaction Theory is attempting to solve this particular problem.