Unraveling the Mysteries of Emergence: From Weak to Strong

Introduction to Emergence

Emergence is a concept that appears frequently in both scientific and philosophical discussions, yet it often remains frustratingly vague. At its core, emergence refers to the idea that higher-level properties or behaviors can arise from lower-level components in ways that are not immediately obvious or predictable. This podcast episode, based on a paper co-authored with Atrusha Parola, aims to bring clarity to the various ways we can meaningfully talk about emergence.

The Importance of Clarity in Discussing Emergence

One of the main issues with discussions about emergence is the lack of precision in terminology. People often use words like "novel," "surprising," or "unpredictable" to describe emergent phenomena, but these terms are subjective and can lead to confusion. The goal of this exploration is to provide a more objective framework for understanding and categorizing different types of emergence.

A Thought Experiment: The Crumpled Paper Ball

To illustrate the concept of emergence, consider a simple thought experiment: Take a piece of paper, crumple it into a ball, and toss it into the air. This seemingly simple action demonstrates several important features of our universe:

1. Gravity is a weak force compared to other forces like electromagnetism.
2. The world is predictable and follows consistent laws of physics.
3. The world is intelligible - we can understand and use these patterns.

Most importantly, this experiment shows that we can make accurate predictions about the behavior of the crumpled paper ball without knowing the exact positions and velocities of all its constituent atoms. This ability to make useful predictions with incomplete information is at the heart of emergence.

Defining Emergence

In the context of this discussion, emergence is defined as a relationship between two levels of description:

1. A lower-level or "micro" theory (e.g., atoms and particles)
2. A higher-level or "macro" theory (e.g., crumpled paper balls)

The key features of emergence are:

1. There is a map from the micro theory to the macro theory that throws away information (many-to-one).
2. The macro theory retains the ability to make useful predictions despite having less information.

Types of Emergence

Type 0: Featureless Emergence

This is the most basic form of emergence, where there is simply a many-to-one mapping from a micro theory to a macro theory, without any additional structure. An example is the classical limit of quantum mechanics.

Type 1: Local Emergence

Local emergence involves systems where:

1. Objects have definite locations in space.
2. Interactions are local (things interact based on proximity).

Examples include:

• Center of mass motion of planets
• Fluid dynamics emerging from atomic theory

Type 1 emergence can be further divided into:

1. Direct emergence: The mapping from micro to macro states is algorithmically simple.
2. Incompressible emergence: The mapping is algorithmically complex.

Type 2: Non-local Emergence

Non-local emergence allows for:

1. Emergent objects that are not locally defined in space.
2. Non-local influences between objects.

This type of emergence is more common in biology and social sciences. An example from physics is the concept of "jerk" (rate of change of acceleration), which requires integrating information over time.

Type 2 emergence introduces the possibility of "filter functions" - additional terms in the dynamics that depend on global configurations. This could explain how seemingly well-understood micro-dynamics might behave differently in complex systems like brains.

Type 3: Augmented Emergence

This is the strongest form of emergence, where:

1. The micro theory is fundamentally incomplete.
2. New ontological entities or influences exist at the macro level.
3. These new entities or influences affect micro-dynamics under certain global conditions.

This type of emergence might be invoked to explain phenomena like consciousness or teleological aspects of nature.

Implications and Conclusions

By providing this framework for categorizing different types of emergence, we can have more productive discussions about complex phenomena. While the author personally does not believe that Type 3 emergence occurs in fundamental physics, the framework allows for clear articulation of how such emergence could theoretically work.

Ultimately, this exploration of emergence serves several purposes:

1. It provides a common language for discussing different types of emergence.
2. It challenges researchers to be more precise in their claims about emergent phenomena.
3. It offers a roadmap for investigating potential cases of strong emergence in a rigorous manner.

By bringing clarity to the concept of emergence, we can better navigate the complex relationships between different levels of description in our universe, from the smallest particles to the largest cosmic structures and everything in between.

Article created from: https://www.youtube.com/watch?v=GJAj_3ZkpRM