Thursday, January 22, 2009

Feynman and Ahavah through Matter

Growing up my oldest brother was a physics buff. He would read physics textbooks for fun and it is from his mouth that I first heard the name Richard Phillips Feynman (1918-1988). Feynman was a particularly interesting individual who has my eternal love for teaching me every bit of physics that I know. This morning on the train I started re-reading the great work Six Easy Pieces- Essentials of Physics Explained by its most Brilliant Teacher. I always expect to get blown away by something in Feynman's work and this morning was no exception, the passage reproduced below is almost exactly the description that my Rebbi gave me of the way an Ohev Hashem views creation and I wanted to share Feynmans description in hopes of assisting with an ahavah reflection.

Matter is made of Atoms

"If, in some cataclysm, all scientific knowledge were to be destroyed, and only one sentence passed on to the next generations of creatures, what statement would contain the most information in the fewest words? I believe it is the atomic hypothesis ( or the atomic fact , or whatever you wish to call it) that all things ae made of atoms- little particles that move around in perpetual motion, attracing each other when they are a little distance apart , but repelling upon being squeezed into one another. In that one sentence, you will see, there is an enormous amount of information about the world, if just a little imagination and thinking are applied.

To illustrate the power of the atomic idea, suppose that we have a drop of water a quarter of an inch on the side. If we look at it very closely we see nothing but water- smooth, continuous water. Even if we magnify it with the best optical microscope available- roughly two thousand times- then the water drop will be roughly forty feet across, about as big as a large room, and if we looked rather closely, we would still see relatively smooth water- but here and there smal football shaped things swimming back and forth. Very interesting. These are paramecia. You may stop at this point and get so curious about the paramecia with their wiggling cilia and twisting bodies that you go no further, except perhaps to magnify the paramecia still more and see inside. This, of course, is a subject for biology, but for the present we pass on and look still more closely at the water material itself, magnifying it two thousand times again. Now the drop of water extends about fifteen miles across, and if we look very closely at it we see a kind of teeming, something which no longer has a smooth appearance- it looks something like a crowd at a football game as seen from a very great distance. In order to see what this teeming is about, we will magnify it another two hundred fifty times and we will see something similar to what is shown in Figure 1-1( not shown). This is a picture of water magnified a billion times, but idealized in several ways... Notice that there are two kinds of " blobs" or circles to represent the atoms of oxygen and hydrogen, and that each oxygen has two hydrogens tied to it. ( Each little group of an oxygen with its two hydrogens is called a molecule) The picture is idealized further in that the real particles in nature are continually jiggling and bouncing, turning and twisting around one another. You will have to imagine this as a dynamic rather than a static picture. Another thing that cannot be illustrated in a drawing is the fact that the particles are " stuck together"- that they attract each other, this one pulled by that one etc. The whole goup is " glued together", so to speak. On the other hand, the particles do not squeeze through each other. If you try to squeeze two of them too close together, they repel.

The atoms are one or two times ten to the neagative 8th cm in radius. Now ten to the negative eight cm is called an angstrom ( just as another name), so we say 1 or 2 angstroms ( A) in radius. Another way to remember their size is this: if an apple is magnified to the size of the earth , then the atoms in the apple are approximately the size of the original apple.

Now imagine this great drop of water with all of these jiggling particles stuck together and tagging along with each other. The water keeps its volume; it does not fall apart, because of the attraction of the molecules for each other. If the drop is on a slope, where it can move from one place to another , the water will flow, but it does not dissappear- things do not just fly apart- because of molecular attraction. Now the jiggling motion is what we reoresent as heat: when we increase the temperature, we increase the motion. If we heat the water, the jiggling increases and the volume between the atoms increases, and if the heating continues there comes a time whrn the pull between the molecules is not enough to hold them together and the fo fly apart and become separated from one another. Of course , this is how we manufacture steam out of water, by increasing the temperature; the particles fly apart becayse of the increased motion."

Feynman continues in this vein throughout the entire book , I thought his ability to illustrate the idea through zooming in on it was particularly useful.

2 comments:

Rabbi Jonathan Sacks said...

Yes indeed Jake. Zooming is quite the way to go. Too bad Feynman didnt learn how to zoom on personal space though.

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