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Emerging Complexity inPhysicsHow does Physical Complexity arise from Basic Particles and Simple Principles?
Ronald WestraDep. MathematicsMaastricht University November, 2005
Part 1
Simple versus Complex
Emergent Complexity in Physics UCM Course LS213 –2005/2006
Course outline
1. Lectures from Syllabus ‘Emergent Complexity in Physics’
2. Focus project: Life as emergent property: the physics of the abiotic processes en route to evolution
Emergent Complexity in Physics UCM Course LS213 –2005/2006
Course Evaluation:
1. Written exam based on open questions based on syllabus; individual; weight: 0.25
2. Written project proposal; group; weight: 0.15
3. Presentation of final project results; group; weight: 0.3
4. Final project paper; group; weight: 0.3
Emergent Complexity in Physics UCM Course LS213 –2005/2006
Focus project :
Title: Life as emergent property
Subtitle: The physics of the abiotic processes en route to evolution
What is ‘complexity’ ???
What is ‘complexity’ ???
What is ‘complexity’ ???
ABOUT “COMPLEXITY” …
‘complexity’ : synonym with difficult, problematical, and tough, opposite to ‘simplicity’.
‘complexity’ : fuzzy and relative; differing from person to person and theory and praxis.
In science the concept of complexity in some cases assumes a more tangible meaning.
COMPLEXITY in science
In the mathematical context complexity often correlates to the notion of computability.
Mathematical complexity theory: the ‘combinatorial complexity’ of an algorithm is precisely defined in terms of algorithmic iterations and the size of the problem.
COMPLEXITY in science
In Computer Science there is an objective measure of the complexity of an object :
The Kolmogorov-Chaitin complexity: ~ the number of symbols required to specify an object in any conceivable formal language.
COMPLEXITY in science
In natural sciences the concept of complexity is not precisely defined.
What are the characteristics and conditions for complexity in physics?
How does complexity originate? Can complexity evolve from simplicity?
Can we distinguish conditions and laws for complexity?
TYPES of COMPLEXITY
intrinsic versus extrinsic complexity.
compare the physical world of interacting elementary particles to a classical theater with various dramatis personae
‘intrinsic’ complexity refers to the complexity of one specific player or the plot of the play,
‘extrinsic’ complexity refers to the complexity that stems from increasing the number of actors involved in our drama.
Can complex systems evolve from merely increasing the number of effectively simple agents?
What is ‘complexity’ ???
Intrinsic Complexity?
(NON) LINEARITY
Linear system : any combination of subsystems behaves exactly similar, and any linear scaling results in a similar system.
Linear system : time evolution result in similar systems.
Linear system : open for mathematical scrutiny, hence understanding, hence predictability.
Linear systems are systems that obey the superposition principle; any two solutions of the system van be added together to form a valid new solution.
In contrast, two solutions of a nonlinear equation cannot be added together to form another solution.
Linear dynamics: laminar flow
Linear dynamics: laminar flowNon-linear dynamics: turbulent flow
Non-linear dynamics: turbulent flow
Complex non-linear dynamics
GUIDING PRINCIPLES in NATURE
The laws physical systems for evolution towards complexity.
Examples : Self-organization, Self-Organized Criticality.
Conservation Laws: Energy, Momentum, Angular Momentum, Particle-type
Self-organization: cristal lattice
Self-organization: patterns in shells
Self-organization: vessicules
GUIDING PRINCIPLES in NATURE
The laws of Nature: Are there laws of Nature ???
CHALLENGES IN CURRENT PHYSICS
1. The most complete theoriy in physics, the Standard Model, is incomplete (does not include gravity) and phenomenological (contains free parameters) and does not have an appealing mathematical structure.
2. From Astronomy it has becone clear that there is much more mass in the Universe than we can observe.
3. We now observe that the expansion of the Universe defies the models for Cosmology.
Focus project :
Life as emergent propertyThe physics of the abiotic processes en route to evolution
Emergent Complexity in Physics UCM Course LS213 –2005/2006
Focus project :
Title: Life as emergent property
Subtitle: The physics of the abiotic processes en route to evolution
Emergent Complexity in Physics UCM Course LS213 –2005/2006
Life as emergent property
Description:
Evolution has shaped all aspects of our planet, from the dynamics and chemistry of its atmosphere to the color of your eyes. From geological evidence we know that immediately after its formation some 4.6 billion years ago our planet started as a place void of - and even extremely hostile to – life as we know.
Emergent Complexity in Physics UCM Course LS213 –2005/2006
Life as emergent property
Yet some 0.8 billion years later fossil evidence unambiguously shows that life had conquered earth. From that moment on evolution acted as the engine for the ever increasing complexity, thus shaping the present ecosystems around us.
Emergent Complexity in Physics UCM Course LS213 –2005/2006
Life as emergent property
From geological evidence we can infer the physical conditions and the chemical composition of the primordial earth. Using this knowledge, in the fifties of the previous century, Miller and Urey performed laboratory experiments in which they found that standard chemical processes in the primordial atmosphere under the influence of energy sources such as lightning, ultraviolet light, or shock (meteorite impacts) the vital amino acids found in nature formed spontaneously, amongst a host of other organic molecules essential for life.
Emergent Complexity in Physics UCM Course LS213 –2005/2006
Life as emergent property
This observation has bridged our gap of knowledge regarding the abiotic earth of 4.6G years ago and the earliest evidence of life 3.8G years ago. The route from the abiotic world to the earliest true forms of life is called the prebiotic evolution. Several mechanisms have been proposed for the process of prebiotic evolution. However, as long as there is no indisputable geological or fossil evidence this will remain a very speculative corner of science.
Emergent Complexity in Physics UCM Course LS213 –2005/2006
Life as emergent property
Alternatively, an acceptable theory for prebiotic evolution could consist of a collection of steps of increasing complexity, where each step is physically consistent and would lead naturally to the next step.
Life as emergent property
Life as emergent property
Objectives:
1. Basic definitions of biological life and biotic evolution.
2. Same for artificial life and prebiotic evolution.
Life as emergent property
Objectives:
3. A survey of current theories for prebiotic evolutions, including the following aspects (including the panspermia theory):• Assumptions on the starting point (the prebiotic world)• Mechanism(s) for coding (genotype)• Mechanism(s) for variation• Differential fitness • Feedback of environment on fitness
Life as emergent property
Objectives:
4. Description of an alternative theory, and comparison with current state-of-the-art.
Life as emergent property
Research aspects:
• What is the earliest evidence or indication of life on earth?
• Panspermia: extraterrestrial origin
• Miller or Urey-Miller experiments
• Do the Urey-Miller experiments indicate the formation of lipids?
Life as emergent property
References:
1. Cairns-Smith, Seven clues for the origin of life.
2. R. Dawkins, Selfish gene (later editions), note 1 with page 14 regarding comment on Cairns-Smith.
3. Theory of Evolution, J.M. Smith, chapter 6
4. Miller, Urrey, Experiments
THE STUDENT PROJECT :
This year (2005) there will be a special student assignement
LIFE AS AN EMERGENT PROPERTY
LIFE AS AN EMERGENT PROPERTY
coacervates
Oparin
Haldane
Miller
LIFE AS AN EMERGENT PROPERTY
Oparin-Haldane Theory
Working independently, in the 1920s, Aleksandr Oparin and J. B. S. Haldane proposed similar theoretical schemes for how life may have originated on Earth (see life, origin).
Hence, the term "Oparin-Haldane Theory" is sometimes used when referring to their views.
The Early Earth 4.6 Bilion yrs ago
Oparin-Haldane Theory
coacervates
Miller-Urey experiment
Miller-Urey experiment
Inorganic molecules
External energy Organic molecules
Prebiotic Evolution
Organisms
Biotic Evolution
Cycleof
increasing complexity
The End
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