What is a Complex System?

Systems Innovation
6 May 201710:24

Summary

TLDRThis module delves into the concept of complex systems, acknowledging the lack of a formal definition and offering a working one. It defines a system as a set of elements with connections, leading to emergent organization. Complexity arises from many distributed parts with local interactions and self-organization, creating hierarchical structures. Key properties include interdependence, non-linearity, high connectivity, and autonomy, which together drive the emergence of new patterns and the adaptability of complex systems.

Takeaways

  • 🔍 A complex system is a special class of system without a formal definition, characterized by multiple perspectives and opinions.
  • đŸ§© A system consists of elements and relations, where unordered systems lack specific structure or order, while ordered systems can function as a whole.
  • 🌟 Emergence is a key concept in complex systems, where a global pattern of organization arises from the interaction of parts, leading to a coherent whole.
  • 🌐 Complex systems are hierarchical, with elements nested within subsystems that form larger systems, creating a multi-dimensional structure.
  • 🔄 Non-linearity is a pervasive theme in complex systems, where the interaction of parts can lead to exponential growth or decay, and sensitivity to initial conditions.
  • 🔗 Connectivity is a defining feature of complex systems, with dense interconnectivity shaping the system's structure and behavior.
  • 🌐 The concept of space is redefined in complex systems through the topology created by connectivity, focusing on network positions and degrees of connectivity.
  • 🩜 Autonomy and adaptation allow elements within complex systems to self-organize and evolve, leading to diverse and heterogeneous responses to phenomena.
  • 🌿 Evolution plays a role in complex systems, where elements are subject to selection pressures, leading to adaptation and increased complexity.
  • 🔑 The four primary parameters of complexity include the number of elements, non-linearity, connectivity, and autonomy/adaptation, shaping the macro-scale evolution of systems.

Q & A

  • What is the working definition of a complex system as presented in the script?

    -A complex system is a special class of system consisting of many parts that are distributed with local interactions and self-organization, giving rise to new emergent levels on different scales. It has a hierarchical structure with elements nested inside subsystems, which in turn form part of larger systems.

  • How does the script differentiate between an ordered and unordered system?

    -An unordered system is a set of things without a specific structure or order, described by listing its elements and their properties. In contrast, an ordered system has parts that are arranged in a specific way, functioning together as a whole and exhibiting a global pattern of organization.

  • What is meant by the term 'emergence' in the context of complex systems?

    -Emergence refers to the phenomenon where a whole new level of the system develops, which then starts to interact with other systems in its environment, leading to the development of new patterns of organization and another level of organization.

  • Why is the number of parts and their distribution considered a primary source of complexity in a system?

    -The number of parts and their distribution contribute to complexity because complex systems consist of many different parts that are distributed out without centralized control, leading to the formation of organization through local interactions and self-organization.

  • How does interdependence and non-linearity contribute to the complexity of a system?

    -Interdependence and non-linearity contribute to complexity because the combined effect of parts can be greater or less than the sum of their individual properties due to their interconnected nature, leading to exponential growth or decay and sensitivity to initial conditions.

  • What is the significance of connectivity in complex systems?

    -Connectivity is significant as it defines the system's nature and structure. At a critical level of connectivity, the system becomes a network of connections, and the focus shifts to how things flow within this network, redefining space in terms of network topology.

  • How does autonomy and adaptation contribute to the complexity of a system?

    -Autonomy and adaptation contribute to complexity by allowing elements within the system to synchronize their states locally or cooperate, leading to the emergence of patterns of organization from the bottom up without centralized coordination.

  • What is the role of feedback loops in complex systems?

    -Feedback loops play a crucial role in complex systems by creating non-linear interactions over time, which can lead to exponential relations between input and output, and potentially trigger phase transitions or rapid changes in the system.

  • How does the script explain the concept of hierarchy in complex systems?

    -The script explains that complex systems have a hierarchical structure where elements are nested inside subsystems, which in turn form part of larger systems. This multi-dimensional property means they are composed of many elements on many different scales, with all levels affecting each other.

  • What is the butterfly effect, and how does it relate to complex systems?

    -The butterfly effect is a concept in chaos theory that suggests small changes in initial conditions can lead to significant and unpredictable outcomes in complex systems. It illustrates the sensitivity to initial conditions, where minor variations can trigger large systemic effects.

  • How does the script define a system?

    -A system is defined as a set of parts called elements and a set of connections between these parts called relations. The elements can be ordered or unordered, and the relations determine how the parts interact and contribute to the overall functionality of the system.

Outlines

00:00

🔍 Introduction to Complex Systems

This paragraph introduces the concept of complex systems, noting the absence of a formal definition and the existence of multiple perspectives. It describes a system as a collection of elements with connections called relations. The paragraph differentiates between ordered and unordered systems, using examples like a pile of stones and a car to illustrate the concept of emergence, where the whole exhibits properties beyond the sum of its parts. The discussion then moves to the self-organization of parts into a coherent whole, leading to new levels of organization. The paragraph emphasizes the hierarchical structure of complex systems, where elements are nested within subsystems, contributing to a multi-dimensional and interconnected nature. It introduces the idea that complex systems consist of many parts with local interactions and self-organization, leading to emergent levels on different scales.

05:01

🌀 Key Properties of Complex Systems

The second paragraph delves into the properties that define complex systems, starting with the idea that they consist of many parts without centralized control. It discusses the phenomenon of emergence, where local interactions lead to new levels of organization. The paragraph then addresses interdependence and non-linearity, explaining how the combined effect of parts can be greater or less than the sum of their individual properties due to their interconnected nature. Examples such as sound waves and division of labor are used to illustrate non-linearity. The concept of phase transitions and sensitivity to initial conditions, central to chaos theory, are introduced with the butterfly effect as an example. The paragraph also covers the importance of connectivity in complex systems, highlighting how increased connectivity transforms systems into networks and redefines space in terms of network topology. Lastly, it touches on autonomy and adaptation, explaining how elements within complex systems can synchronize or cooperate, leading to diverse responses and the capacity for evolution and adaptation without centralized coordination.

10:02

🌐 Summary of Complex Systems Characteristics

The final paragraph summarizes the key characteristics of complex systems that have been discussed. It reiterates that complex systems are a special class of systems defined by a set of elements and their relations. The paragraph emphasizes the importance of the number of elements and the hierarchy within the system, non-linearity and its implications for system behavior, and the role of connectivity in shaping system structure. It concludes by discussing autonomy and adaptation as critical factors that enable self-organization and evolution on a macro scale, shaping complex systems through processes akin to natural selection.

Mindmap

Keywords

💡Complex System

A complex system, as discussed in the video, is a special class of system that lacks a formal definition but is characterized by a set of elements and relations between them. It is a concept that is central to the video's theme as it sets the stage for understanding the various properties and behaviors of such systems. The video uses examples like a car's parts working together to form a functional vehicle and the organization of cells and organs in a body to illustrate how complex systems emerge from the interaction of their parts.

💡Elements

Elements in the context of complex systems refer to the individual parts or components that make up the system. They are the basic units that, when connected through relations, contribute to the overall functionality of the system. The video explains that these elements can be ordered or unordered, and it is through their specific arrangement and interaction that complex systems exhibit emergent properties, such as the cells in our body forming a complex organism.

💡Relations

Relations in complex systems denote the connections between elements. These are what give structure and order to the system, allowing the elements to interact in a meaningful way. The video emphasizes that it is through these relations that a system can function as a coherent whole, rather than just a collection of isolated parts. An example given is the specific arrangement of parts in a car that enables it to operate as a transportation vehicle.

💡Emergence

Emergence is a key concept in complex systems, referring to the phenomenon where a new level of organization or pattern arises from the interaction of the system's elements. This emergent behavior is not simply the sum of the individual parts but represents a higher level of organization. The video uses the example of a car's functionality emerging from the specific arrangement of its parts and the global system of an organism emerging from the organization of cells and organs.

💡Hierarchy

Hierarchy in complex systems refers to the multi-level structure where elements are nested within subsystems, which in turn are part of larger systems. This concept is integral to the video's message as it illustrates the layered nature of complex systems, such as how individuals form social groups, which form broader societies, and so on. The video highlights that these systems are not flat but have a hierarchical structure that contributes to their complexity.

💡Interdependence

Interdependence in complex systems means that the elements are highly interconnected and rely on each other for the system's overall functioning. This interdependence leads to non-linearity, a key characteristic of complex systems. The video explains that the interdependence creates a situation where the whole is more than the sum of its parts, as seen in the division of labor in human communities or the cancellation of sound waves through interference.

💡Non-linearity

Non-linearity is a fundamental concept in the discussion of complex systems, indicating that the behavior of the system is not directly proportional to the inputs or changes in its elements. The video describes non-linearity as a pervasive theme, where the combined effect of elements can be greater or less than the sum of their individual properties due to their interdependent nature. This can lead to exponential growth or decay, known as phase transitions.

💡Connectivity

Connectivity in complex systems refers to the density and structure of the interconnections between elements. The video emphasizes that as connectivity increases, the system's nature is more defined by its network of connections rather than the properties of individual components. High levels of connectivity can lead to the system being perceived as a network, where the position and degree of connectivity within the network structure become crucial.

💡Autonomy

Autonomy in the context of complex systems means that the elements have a degree of independence and can operate according to their own rules or instructions without centralized control. The video discusses how autonomy allows for self-organization and adaptation, leading to the emergence of patterns and organization from the bottom up. Examples include flocking birds, the internet, and economies, where elements coordinate locally to create macro-level patterns.

💡Adaptation

Adaptation in complex systems is the capacity of elements to adjust to their local environment, which contributes to the system's ability to evolve and change over time. The video explains that with autonomy and adaptation, complex systems can respond diversely to phenomena, leading to heterogeneity and high levels of diversity. Adaptation is a key driver of evolution in complex systems, as seen in ecosystems, markets, and democracies, where elements are subject to selection pressures.

Highlights

Complex systems have no formal definition and are subject to various perspectives and opinions.

A system is defined as a set of parts (elements) and connections (relations) between these parts.

Unordered systems lack specific structure or order, such as a pile of stones.

Ordered systems function together as a whole, leading to the emergence of a global pattern of organization.

Complex systems are characterized by the emergence of new levels of organization through self-organization.

Complex systems consist of many parts distributed without centralized control.

The phenomenon of emergence leads to new levels of organization interacting with the environment.

Complex systems exhibit a hierarchical structure with elements nested within subsystems.

Interdependence and non-linearity are key features of complex systems.

Non-linearity can result in exponential growth or decay due to feedback loops.

Sensitivity to initial conditions, as seen in chaos theory, is a central concept in complex systems.

Connectivity is a defining feature of complex systems, often appearing as networks.

Autonomy and adaptation allow elements within complex systems to self-organize and evolve.

Complex systems are often heterogeneous with high levels of diversity.

Elements within complex adaptive systems are subject to evolutionary forces of selection.

The macro scale system adapts to its environment through decentralized coordination and evolution.

Transcripts

play00:03

in this module we will be trying to

play00:05

define what exactly a complex system is

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before we start we should note that

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there is no formal definition for what a

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complex system is and thus there remains

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many different perspectives and opinions

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on the subject what we present here is

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just a working definition

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firstly a complex system is a special

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class of system a system is simply a set

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of parts called elements and a set of

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connections between these parts called

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relations these parts can be ordered or

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unordered an unordered system is simply

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a set of things because there is no

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specific structure or order we can

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describe a set simply by listing all of

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its elements and their properties so a

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pile of stones on the ground is an

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example of an unordered set as there is

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no pattern or order to the system we can

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only describe it by describing the

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properties of each element in isolation

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and then adding them all up with the

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whole set being nothing more than the

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sum of its individual parts

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if in contrast through the relations

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these parts are ordered in a specific

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way then they can function together as

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an entirety and out of these parts

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working together we get the emergence of

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a global pattern of organization that is

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capable of functioning as a coherent

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whole for example if all the parts in

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our car are arranged in a specific way

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then we will have the global

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functionality of a vehicle of

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transportation or out of the specific

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arrangement of billions of cells and the

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different specialized organs that make

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up our body we get the emergence of a

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global system that enables us to operate

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as an entire organism so that is the

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basic model of the system it consists of

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elements and relations when those

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elements work together we get the

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emergence of a new level of organization

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now let's start adding complexity to

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this probably the only property that

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will be in all definitions of a complex

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system is that they consist of many

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parts many parts that are distributed

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out without centralized control

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organization is formed out of the local

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interactions between the parts through a

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process of self-organization that gives

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rise to the emergence of new levels of

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organization with the phenomenon of

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emergence that we were previously

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discussing a whole new level to the

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system has developed which then starts

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to interact with other systems in its

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environment the result being that new

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patterns of organization developed and

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once again we get the emergence of

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another level of organization and so on

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people form part of social groups that

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form part of broader society which in

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turn forms part of humanity the point to

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take away here is that these systems

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have a hierarchical structure this is a

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pervasive phenomenon in our world

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elements are nested inside of subsystems

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which in turn form part of larger

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systems and so on all complex systems

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have this multi-dimensional property to

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them they are composed of many elements

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on many different scales with all of

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these levels affecting each other a

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business is part of a local economy

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which is part of a national economy

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which in turn is part of a global

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economy each is interconnected and

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interdependent with the others we cannot

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fully isolate one component or reduce

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the whole thing to one level and this is

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a primary source of complexity so this

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is our first property to a complex

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system many different parts that are

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distributed out with local interactions

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and self-organization giving rise to new

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emergent levels on different scales

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next interdependence and non-linearity

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the parts to a complex system are highly

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interdependent in this interdependence

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creates non-linearity almost all well

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formulated definitions for complex

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systems involve the term non-linearity

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it is a continuously recurring and

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pervasive theme non-linearity arises

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from the fact that when we put two or

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more things together the result may not

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necessarily be a simple addition of each

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elements properties in isolation in

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contrary we may get a combined effect

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that is greater or less than the simple

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sum of each part because of their

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interdependent nature examples of this

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might be two sound waves that are

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perfectly out of sync cancelling each

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other out through noise interference or

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the division of labor as can be seen in

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many human and insect communities

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resulting in synergies which means the

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output will be far greater than what

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individuals could accomplish in

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isolation

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due to what are called feedback loops

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nonlinear systems may grow or decay at

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an exponential rate these periods of

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rapid change are defined as phase

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transitions

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thus complex systems are known to be

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able to shift or flip into whole new

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regimes within very brief periods of

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time some small change in input value to

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the system can through feedback loops

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trigger a large systemic effect this is

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called sensitivity to initial conditions

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and it is the central idea within chaos

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theory examples of this butterfly effect

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can be seen in financial crises and the

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collapse of ecosystems such as coral

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reefs

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next connectivity many definitions for

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complex systems involve dense or high

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levels of interconnectivity between

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components as we turn up the degree of

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connectivity it becomes the nature and

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structure of these connections that

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define the system as opposed to the

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properties of its components how are

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things connected and what is connected

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to what become the main questions at

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some critical level of connectivity the

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system stops being a set of parts and

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becomes a network of connections and it

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is now all about how things flow in this

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network networks are the Trudy Amma tree

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of complex systems in this connectivity

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reshapes our traditional 3-dimensional

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Euclidean conception of space in complex

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systems like the global air

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transportation system or the financial

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system or the Internet space is

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redefined in terms of topology created

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by connectivity what matters is your

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position in the network structure and

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your degree of connectivity connectivity

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again leads us into the world of

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complexity as the number of relations

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between elements can grow in an

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exponential fashion if we take just a

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handful of elements they can become

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connected and possibly thousands or even

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millions of different ways

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lastly autonomy and adaptation whether

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we are talking about a flock of birds

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the internet or our global economy there

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is no top-down centralized mechanism for

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coordinating the whole system within

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complex systems elements have a degree

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of autonomy often through their capacity

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to adapt to their local environment

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according to their own set of

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instructions without centralized

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coordination and with a degree of

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autonomy elements can synchronize their

play07:32

states locally or cooperate resulting in

play07:35

the emergence of patterns of

play07:36

organization from the bottom up with

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autonomy and adaptation also comes the

play07:41

capacity for a variety of different

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responses for any given phenomenon

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meaning complex systems are often

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heterogeneous with high levels of

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diversity ecosystems and multicultural

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societies are good examples of this

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without centralized coordination complex

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systems develop on the macroscale

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through a process of evolution elements

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within complex adaptive systems are

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subject to the evolutionary force of

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selection where those that are best

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suited to that environment are selected

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and replicated while others are not

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products are subjected to selection

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within a market environment in

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democracies politicians are subject to

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selection by voters and creatures and

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ecosystems are subjected to natural

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selection through competition in such a

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way the whole macro scale system manages

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to adapt to its environment without

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centralized coordination and develop to

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exhibit higher levels of both

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differentiation and integration the

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greater the autonomy and capacity for

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adaptation that elements have the more

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complex the system we are dealing with

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in summary we have been trying to lay

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down a basic working definition for a

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complex system while remembering that

play09:01

there is no formal consensus on the

play09:03

subject we firstly talked about how a

play09:06

complex system is a special class of

play09:08

system we defined a system as a set of

play09:11

elements and the relations between them

play09:14

we saw how when these parts are arranged

play09:17

in a specific order for them to function

play09:18

as an entirety we get what is called the

play09:21

process of emergence whereby a new level

play09:24

of organization emerges we then began to

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add complexity to our model of a system

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by defining it as a product of four

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primary parameters firstly talking about

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the number of elements and different

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levels to the hierarchy within our

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system we then discussed non-linearity

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as another dimension to complexity were

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non-additive interactions and feedback

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loops over time can give us exponential

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relations between the input and output

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to a system and lead to phase

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transitions we also talked about

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connectivity as another driver of

play09:59

complexity as heightened connectivity

play10:02

within complex systems means they often

play10:04

appear to us as networks

play10:06

lastly we discussed how autonomy and

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adaptation enables self-organization in

play10:12

the process of evolution that shapes

play10:14

complex systems on the macro scale

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Étiquettes Connexes
Complexity TheorySystem DynamicsEmergenceSelf-OrganizationNon-linearityFeedback LoopsHierarchical StructureConnectivityAutonomyAdaptation
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