Electric and Magnetic Fields

While taking physics classes I learn quite a few derivations and formulas, but curiously little in the big-picture-conceptual sense . Lately I've been trying to answer this basic question: what are electric/magnetic fields, what in the actual world does this concept represent? This is my current understanding.

Matter interacts with other matter in various ways. One way in which it does so is by charge, charge being an attribute of matter analogous to mass. There are two types of charge which produce opposite effects. They are therefore said to be 'opposite' charges and assigned the arbitrary value of positive and negative. Matter that interacts by virtue of its charge is said to do so electrically, and when charged matter is moving it also interacts magnetically.

In these interactions the charged matter applies equal and opposite force on one another. An electric field is a map of predictions of how this force will be applied to any other charge given a certain degree of charge of a particle; a magnetic field is this set of predictions for moving particles.

Particles only interact magnetically when all the concerned particles have a magnetic field, ie. are charged and moving. One particle will not act magnetically while the another acts electrically, or not at all, or in any other manner. To illustrate this point, consider a static charged particle and a passing charged particle. The static particle has an electric field, the passing particle has both an electric field and a magnetic field. The particles will interact equal and oppositely depending upon charge (attraction or repulsion), causing the static particle to move (thus a magnetic field) and the passing particle to shift in it's motion. They will then begin to act magnetically.

An important thing to note is that since the magnetic interaction of particles is dependant on their velocities, and velocity is relative to the reference frame of observation, magnetic fields are relative. This means that how one observes the interaction is dependent upon the context in which one views it; it does not look the same from every point of view.

Separation of Education and State

Yesterday the Ohio Board of Education voted 11-4 to dispense with a 'mandate' for Ohio schools to teach a 'critical analysis' of evolution in school, along with an accompanying model lesson plan published/disseminated by the Discovery Institute. The move was considered a victory for evolution because it was made on the basis that the 'critical analysis' wording favoured intelligent design in second guessing evolution. What these cheering squads have again failed to notice is that it is now considered acceptable for the legislature to pass approved lesson plans and even specifically mandate what is and is not to be taught in schools.

It's wonderful that this legislation was finally struck down, but not because the opposing view should be sanctioned by the government instead. It should have been struck down because the government has no right to sanction any educational standards.

Electric Field

I have been trying to figure out what exactly is meant by the term electric field. This is what I think so far:

A net/matrix of predictions over distance of the force exerted on a hypothetical particle, P2, by a particle, P1.

This is how my textbook (Matter and Interactions v.2 e.1.5 by Chabay) defines an electric field: Force2 (vector) = charge2 * electric field1 (vector)

Any thoughts; what is an electric field?

Google: 'Chat + E-mail = Crazy Delicious'

Congratulations Google, on another awesome achievment.

"When we launched Google Talk, some people told us what a great idea it'd be to add chat to Gmail. True that. So a couple of us Google Talk engineers approached the Gmail team. They were excited about the idea, and we got to work immediately -- spending a lot of not-so-lazy Sundays huddled in a conference room ... "

Ayn Rand's Birthday

Today most especially, I'd like to recognize what Miss Rand has done for me; even if I can't wish her happiness on her birthday.

Her philosophy made the precious, yet fragmented and undefined, thoughts of my adolescence intelligible. If not for her I don't know if I would have ever figured out how to do it myself. At best, I would have spent many more years in frustration.

Hats off to the woman who is my intellectual guide.