Monthly Archives: December 2015

Poles Apart

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USA Politics are more polarized than usual these days. What does polarized actually mean? The pole is a fundamental concept that gives rise to a vast swath of physical science. Poles are discussed early in the study of electromagnetism—essentially the second half of classical physics.

Earth spins on an axis—an imaginary line that passes through the north and south poles.

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Actually, the axis doesn’t pass through the magnetic poles.

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Earth has a magnetic field. Magnetism arises from charges in motion. Molten iron churns in Earth’s core.

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Metals, like iron, often have an abundance of delocalized electrons. Electrons have negative charges. It’s the motion of these charges that most likely creates Earth’s magnetic field.

The north magnetic pole is a bit off from the axis.

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The same is true for the south magnetic pole.

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Here’s the confusing part: Earth’s geographic north pole is actually a magnetic south pole, and the geographic south pole is a magnetic north pole.

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Why do we call Earth’s magnetic south pole, the north pole? Because an independent magnet’s north pole, points north on Earth. (A compass is just a magnet that rotates about a central point–an axis–with minimal friction.) The north pole of a magnet is attracted to the south pole of other magnets. The arrow of a compass points at Earth’s south pole. That arrow is on the north pole of the independent magnet; hence, we call that direction north.

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I guess we could say the south pole is on the tail of the arrow, but there is a better, simpler way to describe whats happening. It doesn’t matter what point you specify on a magnet. The field passing through the magnet points in one direction.

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Notice that the arrows leave the north pole and enter the south pole. This is what’s called a convention. Conventions are arbitrary things. We could just as easily assume field lines leave south pole and enter north poles. It doesn’t matter. We do need to agree on one or the other so we can communicate about magnetic fields without needless confusion.

Magnetic fields exist inside of magnets too. Remember: magnetic fields come from charges in motion. Most magnets are made of metals. Metals have more mobile charges than other types of materials. The magnetic fields arise from small regions called domains that sometimes align. When the domains point in the same direction, the material is magnetized.

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North and south poles are a false binary reference systems to help us explain magnetic fields. The only crucial characteristic of a magnetic field is direction. (Actually, magnetic field strength is important too, but not necessary in this post.)

USA has a two-party system. Each party serves as a pole of sorts: the Republicans are at one, and the Democrats occupy the other. Partisans at each extreme believe they have philosophies that clearly distinguish themselves from the opposition. We could say the Republicans stand over the south pole while Democrats reside at the northern extreme. It could be the other way, too. Political poles suffer from some of the similar confusing conventions that we see with magnetic poles.

Political poles are similar to magnetic poles in that they don’t really exist other than a means to explain–and complicate in some ways–a more simple phenomenon. For magnetism, poles help us understand magnetic fields. Political poles help us understand historical progress in the distribution and dispensation of power–this is commonly known as governance.

Republicans are typically classified as conservative, while Democrat are pegged as liberals. Conservatives are leery of change while liberals are more eager to make progress–liberals are sometimes called progressive too. Political progress is similar to a magnetic field line in that  it points in one direction. Conservatives and liberals both advocate progress; truly, they differ only in the preferred rate of change. Conservatives like the way things have been done in the past: they know what works and they think it’s best to stick to the tried and true as we move forward in history. Liberals advocate for a quicker pace and they are keen to experiment with new ideas on how to govern.

If you liked this post, you might like A republic if you can keep it and/or Hunter Gatherers in the Quantum Age.

 

An Evolving Universe II–Energy Spreading

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This post is a continuation of An Evolving Universe I—The Greatest. Part II stands alone, but it will be difficult to appreciate and fully understand III without reading I and II first.

Entropy is a central scientific concept; it seems to have more importance in chemistry, and even more so in physics. Entropy is a measure of disorder in a closed system. Closed, in this context, means energy cannot move—maybe flow is a better word—across arbitrary barriers: the system is closed because it’s insulated, so to speak, from whatever is outside the system. The stuff and the space residing outside the barriers may as well not exist because the energy we care about can’t go there.

Energy doesn’t really move or flow. Energy exists in different arrangements; as the number of possible energy holders increases, the more complicated the system. Energy distributes itself according to strict, but simple, laws of probability. Our universe appears to contain a fixed amount of energy. That energy is allocated to a large number of particles—photons, electrons, protons, neutrons, atoms, etc. According to probability alone, energy is more likely dispersed widely across numerous particles as opposed to concentrated on a few, or just one. The level of energy concentration is the measure of order in a system; more dispersed energy makes a more disordered system.

Here’s a good example that might allow you to see the connection between order and energy distribution within a system: Imagine a series of twenty A4 papers, typed on in succession to create a short story. Stack the pages one on top of the other, chronologically. Now, take the stack of papers and throw them into the air. We know what happens: The papers fall back to the ground in a disordered way. It’s impossible to predict how or where they will fall. Reorder the papers in a stack, and then throw them into the air again. The papers fall back in a disordered, but different way than before. Each time we do this, the papers will land in a unique pattern; they will always be disordered compared to the original arrangement. There are an, essentially, infinite number of disordered arrangements of these pages and only one ordered state. Probability tells us the papers are destined to become disordered. Mathematically speaking, it’s unlikely the papers should ever be ordered in a stack that when read, top to bottom, creates a coherent story. The chronological stack is only one of a nearly infinite number of possible arrangement of the papers, and therefore, improbable.

Orderly, concentrated energy eventually becomes disordered, dispersed. Actually, the idea of energy being ordered guarantees misunderstandings. Let’s go back the stack of papers. Not only is it unlikely that the papers will ever exist in chronological order, the papers should rarely be in the same proximity. There are just too many scenarios where the papers are scattered. If the papers are concentrated initially; eventually, they spread out. Our intuition should tell us this is true but we blame it on influences like a person intentionally throwing them into the air. The stack of papers was always doomed to scatter, not because of malicious design or lack of maintenance; the papers will scatter because there’s so many more ways for the paper to scatter than to be stacked chronologically.

Energy prefers to be spread out, dispersed, in much the same way our stack of papers. It’s not that energy strives for disorder; energy tends to spread out on more particles in a system, not because it’s herded along to that end by some shepherd. There’s just so many more ways for energy to spread itself over many particles than to be concentrated on a few, or one.

When energy is concentrated, it’s more probable that it will spread out. Energy’s tendency to move from concentrated to dispersed gives rise to something we are all painfully familiar with: the one-way flow of time. We tend to see time as the master. Time makes our stack of papers scatter. Time disperses energy concentrations. It might be more correct to say the perception of time is created by the overwhelming probability that energy should be spread out, as opposed to concentrated. Time might be the way a conscious being processes the myriad of possibilities present continuously in the now—whatever “now” means. In other words, time is simply a vessel to explore an infinite universe.

Click here to go back to Part I. Here’s Part III.