Saturday, November 1, 2008

Grand Ideas of Science

In his 2007 book, Why Science?, scientist & author James Trefil concludes with a list of "Grand Ideas" of science which could be used as the basis of any core science program aimed at providing scientific literacy to the general population. In short, he argues that these are the scientific concepts necessary for someone to understand issues that arise within society regarding scientific discoveries & issues, and anyone lacking this most basic of understanding is not informed enough to even enter the debate. I reproduce that list here (with his consent), with my own commentary provided.

The universe is regular and predictable.

This core idea provides the very foundation for all of experimental science. In some ways, it is impossible to prove this notion, but in others it is proven by every moment of every day. The universe behaves in a consistent fashion. Every day the sun rises and gravity continues to function. The surprises that come our way tend to be either from incomplete information or inaccurate interpretation of information, not from an inherent chaotic nature to the universe itself.

Since the entire rational nature of scientific inquiry is built on this idea, if one does not understand it (or does not believe it), then they will obviously have difficulty fully appreciating the findings of science.


The energy of a closed system is conserved

This principle is known as the first law of thermodynamics and is fundamental to the manner in which energy flows in our universe. It provides the basis of the law of conservation of energy, which is that energy cannot be created nor destroyed, but only transferred from one form to another.

Heat will not flow spontaneously from a cold to a hot body.

This idea is also known as the second law of thermodynamics and is closely tied into the notion of entropy, or the measurement of disorder within a system. In the simplest form, this means that, over time, any thermodynamic process will lost energy (frequently in the form of waste energy) and, therefore, a perfect engine or "perpetual motion device" cannot be created.

Maxwell's equations govern electricity and magnetism.

Nineteenth century scientist James Clerk Maxwell discovered a key insight into the nature of the universe - that electricity and magnetism were actually manifestations of the same underlying phenomena, which came to be called electromagnetism. For example, a moving particle with an electric charge produces (or induces) a magnetic field. This and other concepts were codified in a series of equations called Maxwell's equations and, over a century later, are fundamental to our understanding of electromagnetism.

Matter is made from atoms.

A concept which was put forth as far back as the ancient Greeks, the core idea of atomism is that the matter we interact with is composed of still smaller things which we cannot see. While the Greek conception of this was that the atoms would be smallest constituent of matter, modern particle physics is, in fact, a very rich field of study which has shown that the atom itself is composed of many constituent particles.

Material properties are determined by the identity & arrangement of atoms.

Or, in the precise words Trefil uses, "The properties of materials depend on the identity, arrangement, and binding of the atoms of which they are made." The nuclear structure of the atom determines what element it is, while it's outer electron structure determines how the atoms can bond together. This is the core of chemistry, chemical physics, and other areas of study.

In the quantum world you cannot measure an object without changing it.

One of the most unexpected findings in all of scientific history, in the tiny realm of quantum physics the line between observer & observed is very fine indeed, to the point of being non-existent. One of the best examples of this issue is in the quantum double slit experiment, where the time of a measurement has a direct impact on how the system behaves ... even in cases when one wouldn't normally expect it to have any impact.

The laws of nature are the same in all frames of reference.

This was the great insight of Albert Einstein, which led to the development of his theory of relativity. Basically, if the laws of nature are the same, regardless of how different observers are moving, then he determined that there had to be a way to translate all observations so that they were consistent. In doing so, he discovered some quite unexpected properties of reality, such as space and time itself appearing inconsistent depending on how two observers were moving.

There is a great deal of energy in the atomic nucleus.

As Einstein developed his theory of relativity, he came to realize that there was an intimate connection between mass and energy. In fact, he discovered that mass was really just another form of energy and that it was actually possible to write an equation - the famed E = mc2 - which related the mass (m) to the energy E, which was based on the speed of light (c) squared. Well, the speed of light is a very large number, so the energy contained within the atomic nucleus is correspondingly also very large (even though the mass itself is very small).

The nucleus is made of particles, which are made of quarks...

Though it was once believed that atoms were the smallest constituents of matter, has been known for nearly a century that this is not the case. Atoms are composed of a nucleus surrounded by negatively-charged electrons. The nucleus itself contains protons (particles with particle charge) and neutrons (particles with neutral charge). In addition, the protons & neutrons appear to be composed of even smaller particles called quarks.

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