Complex System Features Of Complex Systems Emergence

What distinguishes a complex system from a merely complicated one is that some behaviors and patterns emerge in complex systems as a result of the patterns of relationship between the elements. Emergence is perhaps the key property of complex systems and a lot of work is being done to try to understand more about its nature and the conditions which will help it to occur.

1.2 Relationships are short-range

Typically, the relationships between elements in a complex system are short-range, that is information is normally received from near neighbours. The richness of the connections means that communications will pass across the system but will probably be modified on the way.

1.3 Relationships are non-linear

There are rarely simple cause and effect relationships between elements. A small stimulus may cause a large effect, or no effect at all. See nonlinearity.

1.4 Relationships contain feedback loops

Both negative (damping) and positive (amplifying) feedback are key ingredients of complex systems. The effects of an agent's actions are fed back to the agent and this, in turn, affects the way the agent behaves in the future. This set of constantly adapting nonlinear relationships lies at the heart of what makes a complex system special.

1.5 Complex systems are open

Complex systems are open systems - that is, energy and information are constantly being imported and exported across system boundaries. Because of this, complex systems are usually far from equilibrium: even though there is constant change there is also the appearance of stability.

1.6 The parts cannot contain the whole

There is a sense in which elements in a complex system cannot "know" what is happening in the system as a whole. If they could, all the complexity would have to be present in that element. Yet since the complexity is created by the relationships between elements that is simply impossible. A corollary of this is that no element in the system could hope to control the system.

1.7 Complex systems have a history

The historyHistory is often used as a generic term for information about the past, such as in "geologic history of the Earth". When used as the name of a field of study, history refers to the study and interpretation of the record of human societies. The term histor of a complex system is important and cannot be ignored. Even a small change in circumstances can lead to large deviations in the future. This has been referred to as the " Butterfly effectThe butterfly effect is a theorem of chaos theory that small variations in the initial conditions of a dynamical system can produce large variations in the results. Edward Lorenz first analyzed the effect in a 1963 paper for the New York Academy of Scienc."

1.8 Complex systems are nested

Another key aspect of complex adaptive systemsAn adaptive system is a system that is able to adapt its behavior according to changes in its environment or in parts of the system itself. A human being, for instance, is certainly an adaptive system; so are organizations and families. Some man-made syst is that the components of the system - usually referred to as agents - are themselves complex adaptive systems. For example, an economyEconomics is the social science studying how society uses its limited resources to meet desires and wants. Put otherwise, economics studies what, how and for whom society produces. This involves analyzing the production, distribution and consumption of go is made up of organisations, which are made up of peopleAlternate meaning People (magazine) In general, the English word people refers to a specific group of humans, or to persons in a general sense. A people may also be a group of humans which possess a common characteristic, for example nationality, skin col, who are systems of organs controlled by their nervous systemThe nervous system of an animal coordinates the activity of the muscles, monitors the organs, constructs and processes input from the senses, and initiates actions. see Central Nervous System). In animals with brains, the nervous system also generates ands and endocrine systemThe endocrine system is a control system of ductless endocrine glands that secrete chemical messengers called hormones that circulate within the body via the bloodstream to affect distant organs. It does not include exocrine glands such as salivary glandss, which are made up of cells - all of which, at each level in the hierarchy, are complex adaptive systems.

1.9 Boundaries are difficult to determine

It is usually difficult to determine the boundaries of a complex system. The decision is usually based on the observer's needs and prejudices rather than any intrinsic property of the system itself.

For instance, the boundary of an individual human being may appear easy to determine but a little more thought will show some of the ambiguities. For instance, are clothes inside or outside the boundary? If someone stares at you across a room or crowded train, especially in a lustful or aggressive way, have they invaded your boundary? Are your boundaries physical, or emotional? Emotional influence can impact physical existence. At what moment does food become a part of your body?

2 External links

Complexity Digest

Complex Systems from Serendip

Supplements to the Proceedings of the National Academy of Sciences (PNAS):
- Adaptive Agents, Intelligence, and Emergent Human Organization: Capturing Complexity through Agent-Based Modeling
- Self-organized complexity in the physical, biological, and social sciences

Santa Fe Institute (SFI)
- Search (Google) SFI: Complexity

New England Complex Systems Institute

Bandung Fe Institute Official Web

Max-Planck Institute for Physics of Complex Systems

Systems theory

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1 Features of complex systems

1.1 Emergence