Physics Model Determines Dynamics of Friends and Enemies

December 2, 2009 By Lisa Zyga, feature

In these socially balanced and unbalanced configurations of a triangle, solid edges represent friendly relationships, and dashed edges hostile relationships. Image credit: Marvel, et al.
( -- Sometimes friends can become enemies and enemies become friends, and it’s difficult to understand exactly how or why the changes took place. A new study shows that when the shifting of alliances and rivalries is interpreted using principles from social psychology, the overall behavior can be modeled as arising from an energy minimization process. The work is part of a growing line of research that uses tools from physics to analyze complex social systems.

In their study, Seth Marvel, Steven Strogatz, and Jon Kleinberg from Cornell University have used theories from social psychology to classify certain configurations of and enemies as being more stable than others. They show that these configurations can be represented by an energy landscape, in which the overall corresponds to a kind of energy that relaxes as relationships shift between friends and enemies.

In their model, the researchers used plus signs to represent friendships between two individuals, and minus signs when two individuals were enemies. Some configurations in a group were considered balanced, while others were unbalanced. For example, in a balanced configuration, the enemy of your enemy should be your friend, and the friend of your enemy should be your enemy. In the scientists’ model, these balanced configurations require less energy to maintain, and are the global minima in the energy landscape. The configurations of lowest possible energy are those in which all pairs in the network are friends, or in which the network is divided into two “rival factions”: two groups of mutual friends who are antagonistic toward each other.

While this description of the lowest-energy configurations has been studied in previous work, the researchers found that the overall energy landscape is more complex than previously thought. Specifically, they found that “jammed states,” or local minima, occur when a configuration is trapped between adjacent configurations of higher energy, prohibiting it from moving toward the lowest energy state (a balanced configuration). When investigating the structure of these jammed states, the researchers found that these states form more often at lower energies, and higher-energy jammed states are structurally more complex than lower-energy jammed states.

“Earlier work by Antal, Krapivsky, and Redner had shown that jammed states could exist, and so our interest was in developing a more complete picture of the possible energy levels and structures of these jammed states,” Kleinberg said said to “We find that jammed states can exist at surprisingly high energies, and that the pattern of friend/enemy relationships within a jammed state has an inherent complexity that increases as we move higher up the energy landscape.”

These results provide a first look at how social networks can be viewed as energy landscapes that are driven by minimizing social stress (or, by the same token, increasing consistency in relationships). While this study reveals insight into the landscape’s local and global minima, in the future the researchers hope to better understand the large-scale structure. By doing so, they could possibly find pathways leading from the most entrenched conflicts toward states of reconciliation.

“Our model is a theoretical one; it explores the consequences that follow logically from a few simple principles in , and it shows that these consequences can be surprisingly complex,” Kleinberg said. “We think it could help provide a guiding framework for reasoning about real-life social networks in which there is both friendship and conflict, and in particular it could provide a useful perspective for subsequent empirical studies aimed at interpreting the patterns of friend and enemy relations that one finds in real data.”

More information: Seth A. Marvel, Steven H. Strogatz, and Jon M. Kleinberg. “Energy Landscape of Social Balance.” Physical Review Letters, 103, 198701 (2009).

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Dec 02, 2009
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not rated yet Dec 02, 2009
BTW This widely spread negativism toward new ideas is physical phenomena too, comparable with surface tension. Small droplets are repelled by flat water surface, whereas these larger ones are merged a much more easier due their lower surface curvature. The merging of droplets requires temporal formation of thin neck with negative curvature, which is source of strong negative interaction.

In such a way, people can accept often a huge lies easier, then the small bits of truth and the belief in intersubjectivelly accepted negation of apparent connections (so called pathological skepticism) is usually way more attractive for average people, because it requires less thinking, knowledge and understanding of problem.

Just think about it, when you start to believe in some "obvious truth" or when you call someone "a crackpot" next times.
not rated yet Dec 02, 2009
@Alexa: Perhaps posting on the internet isn't the best to disseminate your discoveries. I'm sure there are better ways to convince people. Find a catalyst to lower the amount of energy required for people to seriously investigate your ideas. Apply your theories some how, invent something. I don't think posting on Physorg is doing much more than standing on a street corner and preaching.
Dec 03, 2009
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Dec 03, 2009
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Dec 03, 2009
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not rated yet Dec 03, 2009
The Marvel, Strogatz and Kleinberg's article justifies the opportunistic behavior of people, who are ofter "changing coats" at the moment, some other party takes the leadership. It explains, it just helps society to follow energy density gradient in more "natural" way.

Now we can put a question, why we are still considering such behavior amoral and condemnable, if it could be explained so easy way. The religious and consistent behavior is considered as a rather moral imperative here.
not rated yet Dec 06, 2009
Has any study evidentally proven that humans constantly adhere to the lowest energy conformation?
It seems like a broad generalisation.
not rated yet Dec 08, 2009
Has any study evidentally proven that humans constantly adhere to the lowest energy conformation? It seems like a broad generalization.
They rather tend to follow path of energy spreading, instead of energetic state. This applies for social groups, where individual interests are averaged/compensated mutually, so that people are behaving like chaotic gas. The behavior of individuals is still unpredictable and often altruistic, but such altruism has a good meaning for society as a whole from energy minimization perspective.

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