1. Why doesn't the moon fall down?

Good question! Actually the moon is falling down.

What saves us is that the moon is also going sideways.

After going down a bit and sideways a bit the moon ends up being about the same distance from us that it was at the begining.

I'll tell about another way of looking at it, and an experiment for you soon.

2. Why don't people living on the bottom of the earth fall off?

What do we mean by the "bottom of the earth"? Look at a basket ball. Which part is the bottom? The bottom is the part near the earth, right? For people on the far side of the earth from us "bottom" is still the side near the earth, for them.

Now this is not just words. What makes things fall is gravity. Gravity is a pull between everything in the universe, but far things don't pull as hard as near things, and "big" things pull harder than "small" things. The biggest thing near us is the earth, so we are pulled toward the earth, from whatever part of the earth we are on.

"Big" and "small" are how much material (mass) there is, not how far across the thing is.

3. What are quarks? And why the funny name???

Lots of us wonder about that. What a quark does is easier to understand than why it has that name!

Particles

Physicists hope, someday, to find the smallest, simplest objects in the universe. This sort of object is called a particle. There have been many possible simplest particles but so far they have almost all turned out to be made of something smaller.

No one promised that there would actually be simplest particles, it is just a hope.

Lagos

The hope is that everything else will be made of these simple particles. Perhaps like a toy city is made of houses, the houses are made of walls, the walls are made of lago blocks.

It is hoped that quarks (and electrons) will correspond to the lago blocks.

Strings

There is some reason to suppose that quarks may be a way of looking at objects called strings, not the strings you use for yo-yos. There is also some evidence (Spring 1996) that quarks may also have parts, this would imply that electrons also had parts.

Complexity

Don't blame me if this seems too complicated. I was not consulted in the design.

Here is a little table showing what goes to make up what. You start at the top with the simplest things and see what they make. For example, quarks combine to make protons; nuclei and electrons combine to make atoms.

WHAT'S WHAT IN QUARKS AND SUCH

Particles: The ones above make up the ones below.		Who tries to understand these particles and their connections.
Strings (perhaps)
		Perhaps Physicists, perhaps Philosophers
Quarks	Electrons
		Particle Physicist
Protons, Neutrons, and Mesons
		Nuclear Physicist
Nuclei
		Atomic Physicist
Atoms
		Chemist
Molecules
		Biologist
You

When discovered

All this was discovered in the opposite order: we first discovered people, then molecules (water say), then atoms, then nuclei and electrons, then protons and neutrons, than quarks, then????? For now, and probably for a long time there are no experiments showing strings. This last part will be for you to discover.

Why the name QUARK?

Now, about the name. The name quark was suggested by Murray Gell-Mann, a Nobel Prize winner in Physics and a man widely respected for his great breadth and depth of knowledge. He in famous for being very knowledgeable and precise about many languages and pronunciation. He says in his book The Quark and the Jaguar (p. 180):

In 1963, when I assigned the name "quark" to the fundamental constituents of the nucleon, I had the sound first, without the spelling, which could have been "kwork" Then, in one of my occasional perusals of Finnegans Wake by James Joyce, I came across the word "quark" in the phrase "Three quarks for Muster Mark." Since "quark" (meaning, for one thing, the cry of a gull) was clearly intended to rhyme with "Mark," as well as "bark" and other such words, I had to find an excuse to pronounce it as "kwork." . . . I argued, therefor, that perhaps one of the multiple sources of the cry "Three quarks for Muster Mark" might be "Three quarts for Mister Mark," in which case the pronunciation "kwork" would not be totally unjustified. In any case, the number three fitted perfectly the way quarks occur in nature.

For once, Gell-Mann has been generally ignored, the common quark is rhymed with Mark!

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Please write me at KBCheney@paccd.cc.ca.us.

Last revised 5/18/96