21
Galilei in 1632 (Galilei and Favaro 2020) refined the theory of gravitational influence in the century that followed. Patient observation, new tools, and mathematical
interpretation revolutionized cosmology. We were no longer at the center of the
universe. Understanding how the invisible forces of the sun’s gravity shape the
elliptical paths of the planets under its influence opened the door for human beings
to understand and harness these essential physical forces to systematically shape the
modern world.
Gravity is one of the four primary physical forces that combine to govern how
the material universe behaves. The three other forces that work directly on atomic
and subatomic levels are electromagnetic (Maxwell 2010), nuclear strong (Chadwick
1932), and nuclear weak forces (Fermi 1934). The history of technology over the
last millennium traces our ability to perceive and direct these forces to accomplish
increasingly complex and ambitious tasks.
While force is distinct from energy, the dynamic interplay and conversions
between electrical, chemical, mechanical, thermal, and other forms of energy, which
issue from these forces, set into motion everything on earth. The detailed study of
these phenomena and their effects are the concerns of entire scientific domains and
lie beyond the scope of this book. However, in order to realistically consider the
threats and opportunities we all face, it is necessary to keep in mind that all matter
and energy behave according to fundamental physical laws.
2.3.1 Electrochemical Forces
From the beginning of time and space, these forces unceasingly transform material
systems at every scale from the galactic to subatomic. We are, however, primarily
concerned with the practical problem of how energy affects us, and the things
around us, today and into the relatively near future. The vast majority of stored
chemical energy available on earth is transformed from one single fundamental
source, the sun. Organisms such as plants, algae, and some bacteria that synthesize
their own food from inorganic substances and an external energy source are called
autotrophs. Most autotrophs are photoautotrophic plants that convert the electromagnetic energy in sunlight directly into burnable chemical energy stored in the
plant’s cells. In addition to sunlight, they take in water, mineral nutrients, and atmospheric carbon dioxide and turn it into sugars they use for food through
photosynthesis.
Photosynthesis is the single most important energy transformational chemical
process for nearly every species on earth. It sustains all life. From a point of view
that seeks maximum efficiency in solar energy conversion, photosynthesis is not
very efficient at all. On average, less than 1% of the sunlight is converted into chemical energy through photosynthesis. Given the abundance of plant life on earth,
however, maximum efficiency is not a long-term goal for the effective use of solar
energy for all photoautotrophs. The oxygen they “exhale” as a waste byproduct and
2.3 Four Primary Forces
Galilei in 1632 (Galilei and Favaro 2020) refined the theory of gravitational influence in the century that followed. Patient observation, new tools, and mathematical
interpretation revolutionized cosmology. We were no longer at the center of the
universe. Understanding how the invisible forces of the sun’s gravity shape the
elliptical paths of the planets under its influence opened the door for human beings
to understand and harness these essential physical forces to systematically shape the
modern world.
Gravity is one of the four primary physical forces that combine to govern how
the material universe behaves. The three other forces that work directly on atomic
and subatomic levels are electromagnetic (Maxwell 2010), nuclear strong (Chadwick
1932), and nuclear weak forces (Fermi 1934). The history of technology over the
last millennium traces our ability to perceive and direct these forces to accomplish
increasingly complex and ambitious tasks.
While force is distinct from energy, the dynamic interplay and conversions
between electrical, chemical, mechanical, thermal, and other forms of energy, which
issue from these forces, set into motion everything on earth. The detailed study of
these phenomena and their effects are the concerns of entire scientific domains and
lie beyond the scope of this book. However, in order to realistically consider the
threats and opportunities we all face, it is necessary to keep in mind that all matter
and energy behave according to fundamental physical laws.
2.3.1 Electrochemical Forces
From the beginning of time and space, these forces unceasingly transform material
systems at every scale from the galactic to subatomic. We are, however, primarily
concerned with the practical problem of how energy affects us, and the things
around us, today and into the relatively near future. The vast majority of stored
chemical energy available on earth is transformed from one single fundamental
source, the sun. Organisms such as plants, algae, and some bacteria that synthesize
their own food from inorganic substances and an external energy source are called
autotrophs. Most autotrophs are photoautotrophic plants that convert the electromagnetic energy in sunlight directly into burnable chemical energy stored in the
plant’s cells. In addition to sunlight, they take in water, mineral nutrients, and atmospheric carbon dioxide and turn it into sugars they use for food through
photosynthesis.
Photosynthesis is the single most important energy transformational chemical
process for nearly every species on earth. It sustains all life. From a point of view
that seeks maximum efficiency in solar energy conversion, photosynthesis is not
very efficient at all. On average, less than 1% of the sunlight is converted into chemical energy through photosynthesis. Given the abundance of plant life on earth,
however, maximum efficiency is not a long-term goal for the effective use of solar
energy for all photoautotrophs. The oxygen they “exhale” as a waste byproduct and
2.3 Four Primary Forces