Glossary: The Future

All of the following terms appear in this unit. The terms are arranged here in alphabetical order.

atom — A small unit of matter composed of protons, electrons, and usually neutrons. Atoms are basic building blocks of the matter we see in the Universe and on Earth. The number of protons in the nucleus of an atom determines which chemical element it is.

Big Bang — A theory, first articulated in the 1920s, proposing that the Universe started out extremely hot and dense and gradually cooled off as it expanded.

black hole — A region in space of such high density that its gravitational pull does not even allow light to escape. Black holes can be formed by the collapse of large objects such as very large stars.

chemistry — The scientific study of elementary forms of matter and the interactions between them.

climate change — Measurable changes in the climate over long periods of time.

collective learning — The ability to share, preserve, and build upon ideas over time.

complexity — A quality of an object or system that has diverse components precisely arranged in connection with one another (so that new properties emerge which did not exist in the components alone).

democracy — A system of government based upon majority decisions made by voting citizens.

DNA (deoxyribonucleic acid) — The double-stranded molecule, present in all living cells, that contains the genetic information used to form and maintain the cell and passes that information to offspring cells.

Earth — The third planet from the Sun in our Solar System, home to many complex life forms and modern human society.

energy — The capacity to do work, associated with matter and radiation. Includes kinetic energy, potential energy, and chemical energy, among others.

entropy (the law of) — The natural tendency of all things to move from order to disorder. (Note: Although often called the law of entropy, it is more accurate to refer to it as the second law of thermodynamics.)

fossil fuel — A carbon-based material such as coal, oil, or natural gas that can be used as an energy source. Fossil fuels were originally formed when the remains of living organisms were buried and broken down by intense heat and pressure over millions of years.

global warming — The increase in average global temperature caused by high quantities of carbon dioxide in the atmosphere.

globalization — The expansion of exchange networks until they begin to reach across the entire world.

Goldilocks Conditions — Specific set of conditions necessary to enable greater complexity. The reference is to the fairy tale Goldilocks and the Three Bears, in which Goldilocks looks for the porridge, chair, and bed that are “just right.”

gravity — The fundamental force of attraction between any two objects that have mass.

greenhouse effect — A process by which certain trace gases in the Earth’s atmosphere trap heat near the Earth’s surface and so keep the Earth’s climate warmer than it would be otherwise. The Earth emits some of the radiation it receives from the Sun back into space, but greenhouse gases trap some of this radiation before it can escape, thus warming up the climate on Earth, as in a greenhouse.

Homo sapiens — The scientific name for our species, which is thought to have evolved in Africa between 200,000 and 300,000 years ago.

individualism — The emphasis of the importance of the individual’s freedoms and needs over those of the collective group.

life — Four commonly accepted attributes of life are that it uses energy from the environment by eating or breathing or photosynthesizing (metabolism); it makes copies of itself (reproduction); over many generations it can change characteristics to adapt to its changing environment (adaptation); and it can regulate internal conditions in order to maintain a stable state (homeostasis).

Milankovitch cycles — Climate changes that may occur regularly over long time periods of time due to the tilt and wobble of the Earth’s rotational axis and variations in the Earth’s elliptical orbit around the Sun.

Solar System — The Sun and the objects that orbit it; the area in space in which the Sun’s gravitational pull is the dominant force.

star — A huge cloud of simple matter held together by gravity. The star, the first complex entity in the Universe, has structure, stability, and sustained energy flow due to nuclear fusion at its center.

supernova — The explosion of a massive star at the end of its life; most chemical elements are created by supernova explosions.

thresholds of increasing complexity — Moments in the history of the Universe when specific ingredients under the right “Goldilocks Conditions” come together to create something new and more complex.

Universe — All the matter and energy in existence, as well as the space that contains it.