What Is an Empty Core in Game Theory?


Vincent White

Game Theory is a fascinating field of study that has found numerous applications in various fields such as economics, political science, and psychology. One of the concepts that is often discussed in Game Theory is the idea of an Empty Core. In this article, we will delve deeper into what an Empty Core is and its significance in Game Theory.

What is Game Theory?

Game Theory is a branch of mathematics that deals with the study of decision-making strategies in situations where multiple players are involved. It tries to model the behavior of these players and analyze the different outcomes that can arise from their interactions.

Defining the Core

In Game Theory, the Core refers to a set of outcomes that are stable and cannot be improved upon by any coalition of players. A coalition is a group of players who work together to achieve a common goal. For an outcome to be considered part of the Core, it must satisfy two conditions:

  • It must be feasible, meaning that it can actually be achieved by some combination of players’ strategies.
  • No coalition should prefer to deviate from it.

In other words, if all players follow their optimal strategies, then no group should want to change their strategy because they would not benefit from doing so.

The Concept of an Empty Core

An Empty Core occurs when there are no outcomes that satisfy both conditions mentioned earlier. This means that there are always some groups of players who would prefer to deviate from any feasible outcome.

To understand this concept better, let’s consider an example:

Suppose there are three players who have to divide a cake between them. Each player has their own preferences over how much cake they receive.

Player 1 likes chocolate cake and wants at least half of it. Player 2 likes vanilla cake and wants at least one-third of it. Player 3 likes strawberry cake and wants at least one-sixth of it.

Now, if the cake is divided into three equal parts, then it is feasible, but it is not in the Core because Player 1 would prefer to deviate from this outcome. They would rather take a larger share of the chocolate cake and give up some of the vanilla or strawberry cake.

Similarly, if the cake is divided into two parts with one player receiving half and the other two sharing the other half, then this outcome is also not in the Core. Players 2 and 3 would prefer to form a coalition and take a larger share of the vanilla and strawberry cakes respectively.

Therefore, in this example, there is no outcome that satisfies both conditions for being part of the Core. This means that there is an Empty Core.

Significance of an Empty Core

The concept of an Empty Core has important implications for Game Theory. It suggests that there may be situations where cooperation among players cannot lead to a stable outcome. In such cases, players may have to resort to other strategies such as negotiation or coercion to achieve their desired outcomes.

An Empty Core can also arise when players have conflicting interests or when there are incomplete or imperfect information about each other’s preferences or strategies. In such cases, finding a solution that satisfies all parties may be difficult or even impossible.


In conclusion, an Empty Core refers to a situation in Game Theory where there are no outcomes that satisfy both feasibility and stability conditions. It highlights the limitations of cooperation among players and suggests that alternative strategies may be necessary to achieve desired outcomes. Understanding this concept can help us analyze complex decision-making situations and develop better strategies for dealing with them.