# Gradients in Nature

—Dissipating free energy

## Introduction

A gradient is the difference between two interacting systems that creates instability, whether it be a difference in temperature, pressure, chemical concentration, electrical charge, or some other characteristic. A hillside is a common example of a gravitational gradient.
When such a difference exists, there will be spontaneous flow from one system to the other until that difference, or the gradient, is eliminated, and a stable equilibrium is achieved. This happens spontaneously to dissipate the free energy contained in the gradient. As an example, materials tend to move downhill in response to the gravitational gradient.

## Objectives

The objectives of this course are to:
* Encourage students to recognize gradients that occur in nature,
* Recognize the role of gradients in supplying free energy,
* Identify the dissipative structures that form to convert the free energy of gradients into entropy,
* Improve students’ comprehension and analysis of dynamic systems.
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## Gradients in physical systems

Nature is replete with various gradients that play a crucial role in shaping the processes and structures around us. Below are examples of gradients in nature, along with the structures that form to dissipate the free energy associated with each gradient:
* Temperature Gradient:
** Structures: Wind and air currents, ocean currents, convection currents in liquids, and the movement of warm and cold air masses.
* Concentration Gradient:
** Structures: Cellular membranes, which control the passage of ions and molecules in and out of cells, as well as diffusion processes in general.
* Pressure Gradient:
** Structures: Wind patterns, atmospheric pressure systems (like high and low-pressure areas), and oceanic circulation patterns driven by differences in atmospheric pressure.
* Chemical Potential Gradient:
** Structures: Cell membranes, which regulate the movement of ions and molecules between different compartments of a cell.
* Electrochemical Gradient:
** Structures: Ion channels and pumps in cell membranes, which help maintain the balance of ions across the membrane, vital for processes like nerve signaling and muscle contraction.
* Gravitational Gradient:
** Structures: Rivers and streams, which flow downhill due to the gravitational gradient, and geological formations like mountains and valleys.
* Hydrostatic Pressure Gradient:
** Structures: Plant roots and vascular systems, which transport water and nutrients from the soil to various parts of the plant against the force of gravity.
* Electric Potential Gradient:
** Structures: Lightning, where the electric potential gradient between charged regions in the atmosphere is discharged in the form of a lightning bolt.
* Vapor Pressure Gradient:
** Structures: Evaporation processes, where the vapor pressure gradient between a liquid and the surrounding atmosphere drives the movement of molecules from the liquid phase to the gas phase.
* pH Gradient:
** Structures: Proton pumps in cellular membranes, which help establish and maintain pH gradients across cell membranes and within cellular compartments.
* Osmotic Gradient:
** Structures: Kidneys in vertebrates, which maintain the balance of water and electrolytes in the body by responding to osmotic gradients.
* Light Intensity Gradient:
** Structures: Phototropism in plants, where the variation in light intensity causes plants to grow towards the light source.
These gradients and the associated dissipative structures are fundamental to the functioning of natural systems, driving processes that shape our world and enable the complexity of life to thrive.
In the book The Romance of Reality, author Bobby Azarian hypothesizes that abiogenesis—the origins of life—created structures that dissipate the thermodynamic free energy of the temperature and chemical gradients present at hydrothermal vents.

### Assignment

Expand the list above by
* Identifying additional naturally occurring gradients, and
* Identifying additional dissipative structures for one or more of the identified gradients.

## Gradients in social systems

In social contexts, various gradients emerge within structures, cultures, regions, classes, and political constructs. These gradients often lead to the formation of dissipative structures that help manage the flow of energy, information, and power.
Each of these gradients and dissipative structures are social constructs.
Here are examples of gradients and the corresponding structures that emerge to handle them:
* Wealth Inequality Gradient:
** Dissipative Structures: Welfare systems, progressive taxation, social safety nets, and charitable organizations that aim to redistribute resources and alleviate economic disparities.
* Educational Opportunity Gradient:
** Dissipative Structures: Affirmative action policies, scholarship programs, educational grants, and initiatives to improve access to quality education in disadvantaged communities.
* Cultural Diversity Gradient:
** Dissipative Structures: Multicultural policies, diversity and inclusion programs, cultural exchange initiatives, and platforms that promote cross-cultural understanding and respect.
* Political Power Gradient:
** Dissipative Structures: Democratic governance systems, checks and balances, independent judiciaries, and mechanisms for citizen participation that ensure power is distributed and shared.
* Information Access Gradient:
** Dissipative Structures: Freedom of the press, open access to information, public libraries, and initiatives to bridge the digital divide, ensuring equitable access to knowledge.
* Social Mobility Gradient:
** Dissipative Structures: Equal opportunity laws, vocational training programs, mentorship initiatives, and policies that enable individuals to move up the social ladder regardless of their starting point.
* Healthcare Disparity Gradient:
** Dissipative Structures: Universal healthcare systems, public health campaigns, community clinics, and initiatives targeting underprivileged populations to ensure equitable access to healthcare.
* Gender Equality Gradient:
** Dissipative Structures: Gender quotas in politics and corporate leadership, advocacy for equal pay, anti-discrimination laws, and movements promoting gender rights.
* Environmental Impact Gradient:
** Dissipative Structures: Environmental regulations, carbon pricing, renewable energy incentives, and global agreements addressing climate change to mitigate environmental imbalances.
* Technology Access Gradient:
** Dissipative Structures: Tech literacy programs, public technology centers, initiatives to provide affordable internet access, and efforts to bridge the digital divide.
* Language and Communication Gradient:
** Dissipative Structures: Translation services, language education programs, multicultural media outlets, and efforts to preserve and promote minority languages.
* Racial Inequality Gradient:
** Dissipative Structures: Affirmative action policies, anti-discrimination laws, diversity training programs, and advocacy for racial justice to counteract racial disparities.
In each of these cases, the dissipative structures are intended to help address and manage the imbalances inherent in social structures, contributing to a more equitable and harmonious society.

### Assignment

Expand the list above by
* Identifying additional gradients in social systems, and
* Identifying additional dissipative structures for one or more of the identified gradients.
* What is your role in creating, sustaining, or dissipating these gradients?

## Recommended Reading

Students who are interested in learning more about gradients in nature may wish to read these books:
* Azarian, Bobby (June 28, 2022). The Romance of Reality: How the Universe Organizes Itself to Create Life, Consciousness, and Cosmic Complexity. BenBella Books. pp. 320. ISBN 978-1637740446.