Saturday, March 12, 2005

Day

Dear Reader,

I have been learning to tell time.

For our D&D games, I have been researching how the heathen Anglo-Saxons told time. They used two calendars in parallel: the Julian calendar, which was an early draft of ours, and their own lunar calendar. Learning about them in enough detail to use them in our games has taught me how much I took for granted about how we tell time today.

Designing a calendar system is not easy. The different units by which we measure time do not divide into one another evenly, and we have no fixed frame of reference for measurement.

For example, what is a day?

One naive answer is twenty-four hours, but that turns out to be circular reasoning because an hour is defined as a fraction of a day, and has no other natural meaning. The day is the natural unit, but what is it?

A second naive answer is that it is the span of time from midnight one day to midnight the next, but this turns out to be the first answer in disguise. After all, when is midnight? It is a repeating point in time spaced out every twenty-four hours, which takes us back to an hour being an arbitrary fraction of a day, and back to the original question, what is a day?

A third naive answer is that it is the time from sunset one day to sunset the next, or from sunrise to sunrise. This captures an important element of the definition of a day, but not all of it. We do know the sun rising and setting is involved, but the time of sunrise and sunset ebbs and flows through the seasons, with the daylight longer in the summer and shorter in the winter. Yet we know the answer we are looking for describes something of approximately constant length throughout the year. This answer does not satisfy that criterion, but it does correctly identify that our definition is related to the relationship between the sun and the earth, particularly to the cycles of day and night. Any definition of a day that runs out of sync with the cycles of day and night cannot be right. So again I ask what is a day?

A fourth answer, a more astronomical answer, is one complete rotation of the planet Earth, but this turns out to be subtly inaccurate. What counts as a full rotation? If we watch the second hand move from 12 around back to 12 on a clock, we can see that we are thinking about a complete rotation as returning to the starting point on a fixed reference. We have no fixed reference for the Earth's rotation, but if we approximated one, say by using the stars, or by projecting an imaginary frame of reference on space around us, the answer is still wrong. The result of doing this would be that over the course of a year, midnight would rotate around through the day as the earth revolves around the sun. Midnight would sometimes be at night, sometimes at sunrise or sunset, sometimes during the day, gradually shifting with the seasons. This seemingly reasonable answer, which is the one given by all the people I know who think they are smart people, is mathematical and astronomical but false.

A more correct answer (but no promises) is that a day is slightly more than one complete rotation of the planet Earth. The line of the Earth's orbit around the sun is our guide to the length of a day. In the almost-day it takes for the Earth to spin completely around, the Earth has also moved just under one degree around its orbit line, changing the sun's position with respect to the Earth by one degree. For the times of day to stay stable, for example for midnight to remain in the middle of the night and noon to remain in the middle of the day, the start and end of each day must remain oriented toward the sun. Since during the course of one day the Earth's revolution around the sun changes its orientation by almost one degree, the Earth must rotate just a little bit more (almost one degree) than one complete rotation to compensate, to line back up with the orbit line and with the sun. That way, noon stays mid-day and midnight stays...well, you get the picture.

If this explanation does not make sense to you, ask me in the comments and I will explain it differently.

It is easy to explain what a day is with a picture but even with words it is pretty easy to explain. So why do we not explain it this way in first grade? Everyone should know what a day is. Why do even most intelligent people define it incorrectly?

Sincerely yours,
Rick

Extra credit: Explain why a day is a about a degree more than one complete rotation instead of about a degree less. What would have to be different for a day to be about a degree less than a complete rotation?

Thursday, March 10, 2005

Thirteenth Dose

Dear Reader,

Enough with the silence! This year has not been about depression, about silence, withdrawal. It has been a good year so far. I started strength training at the start of the year. Beverly and I started scheduling free time at the same time. I started taking a nutritional supplement called EMPowerPlus on February 7th (and if you suffer from depression, bipolar, or schizophrenia, you must check out the TrueHope website). I now keep a daily log and chart my sleep, exercise, eating habits, hours worked, and so on. Whether it has been one or more of these things, or all of them together, I have not felt depressed since last year.

My blog silence for the past three weeks has been due not to depression but to ambition. I was trying too hard, delaying my posts until I could devote real time to them, with the result that I sketched or outlined four blog entries to every one I posted. I have decided to change the character of my blog to be less formal, more personal, and especially more regular. The quality of composition will go down, but I hope the increased frequency and personal emphasis will increase the blog's value overall. I will try to post more or less daily, but I make no promise.

I have had a sore throat on and off since I wrote last, and continuously since Monday of last week. Today it finally turned into bronchitis. There are two remarkable things about this. First, for the last two decades whenever I get a sore throat I get full bronchitis the very next day; to hold it at bay for a week before succumbing shows real improvement. Second, I am not depressed; I always get depressed when I get sick, but not this time. My mood and programming productivity are carrying on right through the illness. It is weird, but good.

My WorldVistA work is going very well lately. I am programming, updating the website, writing policy documents, keeping up with email, making and answering phone calls, reading books on how to professionalize our corporation, and more.

The weekend of February 18th, Jerry and I camped and hiked at Olympic National Park. We camped at Lake Ozette in his VW Bus, right on the shore of the lake. We hiked west through the rainforest to the coast, then south along the coast from Cape Alava to Sand Point, and then back east through the rainforest. We saw eagles and ravens, black-tailed deer, sea stacks among the crashing waves, miles of gorgeous coastline, and more. What we did not see was a single cloud the whole time. Bizarre but wonderful!

Because of the sore throat, Beverly, Kathy and I have only played Dungeons and Dragons (D&D) once during this time, on Wednesday, February 23rd, but it was a great session. It was our forty-seventh session playing together with these characters. Rhonwen, played by Kathy, and Mireldis, played by Beverly, along with their companions, played by me, are searching the Summerlands for a lost sacred spring. Their anticipated showdown with a malicious woman they had not seen since the fourth session was interrupted when the Summerlands were rocked by devastating earthquakes that preceded the eruption of a dragon from underground. The dragon was powerful but feral, grabbing characters and demanding to know where the sacred spring is, claiming it can smell the spring on them. In the end, the dragon released them but decided to follow them, convinced that they will find the spring for him. When next we play together, the players are concerned about how they will find the spring without revealing its location to the dragon, who the characters sense means the spring ill. It promises to be fun, but it will have to wait until I am over the bronchitis. Game mastering (GMing) is fun, but more tiring than work. It's like writing a script for a play, but then when the curtain goes up having to improvise instead based on highly creative but willful actors. I love it, but I have to go into it with physical and emotional energy and clarity of mind, as well as good notes on the characters, setting, and what I thought might happen. I just cannot do that when my body is fighting off an illness.

I have been reading The Lost Gods of England by Brian Branston and Anglo Saxon Herb Garden by Peter C Horn (for my D&D game), Guidebook for Directors of Nonprofit Corporations by the American Bar Association (for WorldVistA), A Vision of a Living World by the revelatory Christopher Alexander (for wisdom), The Constitution by Page Smith and Cracks in the Constitution by Ferdinand Lundberg (for my duty to my country), Collapse by Jared Diamond (for my duty to humanity), and A Gift of Sanctuary by Candace Robb (partly for D&D, partly for fun). I rotate from book to book with my mood, and during this time only finished the first two on the list, though I will refer back to them over and over over the months ahead to help prepare stories for our game.

At the end of February, with the help of Mike Ryan (who loaned us the DVDs and tapes) I introduced Beverly to the new Battlestar Galactica TV series, which we both enjoy. We have also been watching Veronica Mars, House, The West Wing, Desperate Housewives, Queer Eye for the Straight Guy, and Queer Eye for the Straight Girl. In addition, I have been watching some fun Anime shows recommended by Jerry Goodnough and Brian Lord, along with some truly dreadful horror movies off the SciFi channel.

Musically, my taste lately has run back to classical. I was listening to a lot of Vivaldi last year, but so far this year it is Beethoven's piano sonatas, one after another. I never knew more than Moonlight (#14 in C sharp minor, which I still love) well growing up, so this has been a series of discoveries for me, fixating on a single sonata for weeks after I finally get it and fall in love with it, then moving on to another. At the moment my love is for Pastorale (#15 in D major). I love how it sounds like it begins in the middle of the performance, how quietly it starts, how the main melody has an odd cadence as though it were improvised, as though the pianist were hesitating and then choosing to play something unexpected but beautiful. I love how the first movement develops from this quiet but sweet melody up to a compelling climax before working its way back home. I like the odd mood of the second movement, its strange and slightly mischievous walking theme making it sound like the perfect music for a caper film. The third movement is fine, but does not yet move me as much as the first two, and the fourth movement I do not yet know as well. Other Beethoven sonatas I previously discovered and frequently bounce back to include Tempest (#16 in G major) and Pathetique (#8 in C minor, which I got hooked on after hearing it at The Secret Garden bed and breakfast in Eugene, Oregon when we stayed there last October for Jerry's thirtieth birthday). When I'm not exploring his sonatas, it's back to his Fifth or Ninth symphony (the latter of which just might be my favorite single work of music), or his incomparable violin concerto. These days, it's all Beethoven all the time, and usually just the piano sonatas.

Today, I spent several hours at the office unpacking boxes of books, magazines, and binders full of notes, sorting them, and filing some in bookcases. My brother Rob spent an hour helping me out (thanks!), and after he left I finished. Linda gave me a lift to and from the office so I could bring our vacuum cleaner and get rid of sawdust, pine needles, gravel, and other detritus. Now it's clean and pretty in there, and with the phone line working, the phone recharged, the desk assembled, and my crucial references found and unpacked, I'm ready for business. While I was there, Linda drove my car down to the Toyota dealership in Renton for a much-needed servicing, and she will pick it up for me again tomorrow.

This evening I canceled gaming again due to the bronchitis (and I called Jerry to cancel our Oregon backpacking trip this weekend, and James to cancel strength training tomorrow morning). Instead, Kathy came over and with Beverly we watched the end of second season of Gilmore Girls, and I saw my first Marilyn Monroe movie--Gentlemen Prefer Blondes. We ate Indian food from Chutneys, and I drank pot after pot of herbal tea. Now Beverly has gone to bed and I am staying up long enough to finish typing up this blog entry.

Overall, this has been a good three weeks for me. I hope things are well with you, too, Dear Reader.

Sincerely yours,
Rick