Friday, November 24, 2006

Warning!

Warning! This blog causes your monitor to emit rays at more than 670,616,629 miles per hour!

Of course, this faucet is equally dangerous. That might be cool in the downstairs (laundry room) bathroom, and would appropriately surprise my brother-in-law next time he stayed with us overnight since he sleeps downstairs. But it's a bit expensive for a silly splurge.

Fish for lunch

Eugene has a wonderful fish and chips restaurant. I've recently discovered I enjoy their inexpensive Pacific cod as much as their Alaskan salmon or Pacific halibut.

I'm glad that the restaurant carries fish choices approved by the Seafood Watch, as indicated by the links above.

Happy Thanksgiving

Happy Thanksgiving!

(The holiday has a surprisingly hotly debated history!)

Almost everyone enjoys this holiday. I still have work today, writing a sermon for tomorrow, but am enjoying Thanksgiving leftovers and taking a break now to do some blogging.

Handgun Technology in a Sci-Fi Future

The other day I read that Han Solo's distinctive pistol was based on Winston Churchill's favorite. That seemed very funny for some reason.

Then I saw that another Wikipedia article about Star Wars pistols mentioned that each shot's energy source is an ignited gas. Some of the guns in Firefly are similar.

This prompted me to wonder how handgun technology should be different in my futuristic science-fiction setting.

First, it makes sense to use ignited gas. In modern handguns each cartridge has both a bullet and powder (as well as primer and case). If technology allowed a propellant to be efficiently provided separately from the bullet, then many more bullets could be carried with or in the handgun. Currently there is a paintball gun that uses propane and a spark plug. It is easy to believe that in a futuristic science-fiction setting even better gas canisters (or pairs of gas canisters) are used.

Second, there would be technological advances to help deal with recoil. Rheological fluids are a current first step in futuristic recoil technology. Another alternative easy to imagine is a semi-automatic handgun with two slides, for which each shot not only moves one slide back but the other forward. (Currently pistols do not do this because it would sacrifice reliability too much. Here futuristic technology, combined with cartridgeless bullet, combine to make a good excuse.)

(Note that changing the source of bullet propulsion will not in itself allow any increase in the power of the bullet,
unless a separate technological advance helps deal with recoil. A bullet's kinetic energy is only based on its mass and velocity. There is a limit to how much kinetic energy you can give a bullet without recoil being prohibitive. Modern large-caliber hunting pistols with their most powerful cartidges are already at this maximum: even a strong, experienced shooter using two hands cannot fire two aimed shots in quick succession. )

Third, the design of a bullet (shape and materials) can change. Bullet design works with kinetic energy to determine a bullet's stopping power. Unless the setting also has laws limiting some designs as "too military for normal use", the most dangerous bullets would be frangible with a thin shell around dense metal slivers and deadly chemicals.

Thus I get a vauge picture of what handguns will be like in my futuristic science-fiction setting: gas-ignition, bullets without cartidges, high magazine capacity, perhaps dual-slide, and at least the well-funded criminals using bullets of especially dangerous design.

Saturday, November 18, 2006

Tao of Yeshua: Chapter 33

33
He who knows others is shrewd;
He who knows himself is enlightened.
He who conquers others has power;
He who conquers himself has strength.
He who knows contentment is rich;
He who acts intentionally has purpose.
He who departs not from his allotted place will live long;
He who dies without perishing has life.

Society values shrewdness, power,
and contentment in your social role.
Those who follow Yeshua value enlightenment
inner strength, and purpose in our eternal role.

Thursday, November 16, 2006

Warning Signs for Tomorrow

My early discussions about special relativity and time travel reminded me of the site warning signs for tomorrow! Beware of nonstandard spacetime!

Zogg and Livejournal

A long time ago I linked to The Cuddly Menace, a silly parody of a Little Golden Book.

Through this site of scans of old magazines and books I found some wordless pages from that book. But I don't think I'm about to photoshop another parody.

Livejournal has some really strange communities. Why would the vintage magazine crowd pick Livejournal? (The jumping crowd I can understand. Classic!)

Nice palace, too.

UPDATE: Wow. Follow the last link to the author's journal for more amazing touristy photographs. I always wondered what those big ceramic vases were for.

Pavement Drawings

Oooh. Pretty.

Tao of Yeshua: Chapter 32

32
The Way, unnamed from eternity, had unconstrained potential. Humble, it was inferior to nothing in the world.
If a ruler follows it everyone ruled would follow. Heaven and earth would be in harmony and send down sweet dew.
Not needing to be told, people would follow commands from above.
As soon as it had form it was named.
The name exists so the Saint knows where to abide. One who knows where to abide is safe from all danger.
The Way wants to flow into all things as torrents flow through valleys to the river and the sea.

Yeshua took on birth and life
that we could know how to abide in him.
This cleans our consciences
by removing the evil inclination.
Then we abide in Yeshua,
and he abides in us,
like rivers of living water.

Bright Fire

Today during my lunch break I got to watch a chemistry professor ignite 15 grams of thermite.

Oooh.

Monday, November 13, 2006

Tao of Yeshua: Chapter 31

31
Truly, fine arms cause evil tidings loathed by all beings. The man who follows the Way avoids them.
In domestic protocol the left side is the place of honor, but in military protocol the right side is the place of honor. Why is this?
Since fine arms cause evil tidings they are not instruments proper for a nobleman.
Only as a last resort he wields them, for he values peace and quiet above all.
When he fights he finds no beauty in it.
If he found beauty in it he would be taking pleasure in the slaughter of men!
Those who take pleasure in the slaughter of men will never control all things.
On joyful occasions the left side is the place of honor; on sad occasions the right is valued.
The civil minister stands on the left but the military commander stands on the right:
It is as if he is already mourning those whom he will slaughter.
When the military commander must slaughter many men he should bewail such need with sorrow and lamentation.
Upon a victory in war, his priority is to honor the dead with proper mourning and funerals.

Those who follow Yeshua need not use violence against men.
They are apart from the world
in their responsibility to honor Adonai.
Pity the soldier, who must use violence
to manifest the plans of men.
Support the soldier, who is also set apart from the world,
but is set apart in his responsibility to honor the dead.

Kitten War!

Today's cute site: Kitten War!

It's a site that shows you pairs of cute kitten photos and you pick the cutest of the pair. I know my wife will enjoy it.

Tom's Apples - This Year Through Mid-December

One of the benefits of living in Eugene is Tom's Orchard. They have over 20 varieties of apples. All are wonderful.

The store has a tasting table set up, with the plates of apple slices arranged from sweet to sour.

The signs and staff are helpful in assisting customers pick apples for certain purposes (baked textures, storing well in the garage for months, etc.).

Last year was not a good year for apples, and Tom's closed before Thanksgiving. This year they are staying open until Mid-December.

Tom's Orchard is at 909 East Beacon Avenue. The phone is (541) 688-6753. They have reasonable hours, but are not open every day of the week. If you are in Eugene and have not shopped there, try it!

The Legalities of Self-Defense in Oregon

Oregon has a very low standard for what counts as "deadly force". The law can be summarized with two of its definitions:
"Deadly physical force" means physical force that under the circumstances in which it is used is readily capable of causing death or serious physical injury.

"Serious physical injury" means physical injury which creates a substantial risk of death or which causes serious and protracted disfigurement, protracted impairment of health or protracted loss or impairment of the function of any bodily organ.
This means pretty much any attack with an object counts as "deadly force". The courts do not care if the object is a gun or a baseball bat or a flashlight with teeth. There is even established court precedent for a significant difference in size or weight between two unarmed people to count as "deadly force".

The only way to physically defend yourself without using "deadly force" is with a bright light or chemical spray. These do not cause what is legally classified as serious physical injury.



The above link to Oregon law needs to be read more carefully for sections 161.210 through 161.219, but the summary of appropriate self-defense are these phrases:
...a person is justified in using physical force upon another person for self-defense or to defend a third person from what the person reasonably believes to be the use or imminent use of unlawful physical force...
As in any state, self-defense is okay, but while defending yourself you should not be the one who escalates a situation to include deadly force.

So if someone is yelling insults and pushing you around a little, but has not given any indication that serious physical injury is imminent, it is illegal at that point to try to get them to go away by drawing a gun or smacking them with some sort of club.

Because "home robbery assault" (someone breaking into your home when you are there) and rape so often involve the criminal using deadly force, Oregon courts have set a standard slightly different from how the law actually reads in 161.225: it is always legal to "reasonably believe" in these two crimes will include the criminal using deadly force, and so a defender may always use deadly force. (This is part of the word "assault" in the technical name of what might otherwise be called something like "home invasion burglary".)

Thus Eugene (except in college student housing neighborhoods) has an extremely low incidence of people breaking into homes when people are at home: doing so is asking to get shot, and the courts are not going to be sympathetic if the criminal's family tries to sue.

And thus very few people carry something to hit an aggressor with. Better to carry a chemical spray and/or bright light to help you flee an attack. If you want a weapon as well (and are over 21), you might as well get a concealed handgun permit and have a handgun.



Furthermore, if you are defending yourself outside of your home (and outside an attempted rape), the courts will not be sympathetic if it appears you were eager for the opportunity to use deadly force.

Thus it is legally a bad idea to have a flashlight with teeth or a special self-defense umbrella. These may seem cool to those of us with a Y chromosome. But legally they are asking for trouble after a situation that required you to use them.

Similarly, many people who carry a concealed handgun use a gun without any modifications from factory standards. To help with comfort and safety it is normally recommended to at least consider customizing the grips and tension of the trigger spring of any gun you own. Modifying the sights is also common. For home defense, adding a bright light connected to the trigger or grips is vital. But for a concealed handgun any kind of modification might be seen by a jury as evidence that you were eager to use the gun, leading to trouble after a self-defense situation.

So as nifty as I find the unbreakable umbrellas, I don't think I'll be getting one.

UPDATE: I forgot to mention handloading. Centerfire bullets are expensive. People who shoot for recreation often collect their used cartridge casings and reload them. This is roughly half as expensive as buying new bullets, after you overcome the initial investment of the required tools. But many courts, including in Oregon, have a precedent of seeing handloaded cartridges as a sign of someone eager modify typical bullet behavior (with handloading you can use a different amount of powder or a different weight bullet, although this may lower reliability), and thus eager to use a gun. So many people who carry a concealed handgun only put new, store-bought bullets in that gun when they carry it.

Saved from What? (Book Review: The Way of the Master)

A friend gave me a book that his church is using: The Way of the Master, by Ray Comfort, based upon this program by the same name.

The book has some virtue in stressing how important it is to represent God and the Kingdom of God. But it has a grave theological flaw common to much of American Christianity.

Scripturally, Yeshua saves us from slavery to sin. Before we have faith in Yeshua we are "stuck" being unable to live as virtuously as we would like. Our willpower will never be enough, no matter how much we make deals with ourself or ask God to strengthen it. There is no outside help from God available because God will not send his Spirit into someone enslaved to sin. In Isaiah's words,
Behold, Adonai's hand is not shortened, that it can't save. Neither his ear heavy, that it can't hear. But your iniquities are a separation between you and your God. And your sins have hidden his face from you, so that he will not hear.
Faith in Yeshua allows us to escape slavery to sin. Then God can send his Spirit into us. The apostles call this "making us innocent" (dikaiosune). Just as the word "innocent" in English means both not being guilty and being pure inside, in Greek the same two meanings apply. We are legally in a better position before God, and also able to be pure.

(Note: the word dikaiosune is usually translated "justified", which is accurate but often not meaningful to people, or "righteousness", which is a very bad translation.)

Despite what is often taught, Yesuha's sacrifice does not make our crimes forgiven. Rather, our repentance and faith in Yeshua allow him to forgive us. (If you doubt this, read First John 1:7-10 again.)

Here's a metaphor that came to me this weekend, while discussing theology after Shabbat services. Like all metaphors it has its weaknesses, but it might help here:
Imagine you are in a different country with slightly different traffic laws, and a king.

You don't have a driver's license. No matter how well you drive, you cannot do so legally. The king cannot hire you to work for the government as a courier, or in other ways treat you as a driver without compromising his own justness.

Also, you don't drive perfectly. You have earned a few driving tickets.

Later, you get your driver's license. Now you can drive legally! The king, and everyone else, can relate to you as a legal driver. But you still have those tickets.

You do what is necessary to deal with the tickets, and finally have a clean slate as a legal driver.
In the metaphor, our faith in Yeshua's sacrifice is like gaining the driver's license. Our repentance is like subsequently dealing with the tickets.

My main point is that we are saved from slavery to sin. In particular, we are not saved from God's wrath. God is not angry and eager to punish sinners. Scripture describes God as prefering mercy and hesitant to punish. But he is a just God, and will not compromise his justness. He will only extend so much mercy to people still enslaved to sin.

(Think of how you would be more willing to be forgiving, and more just in acting forgiving, to a friend or family member who got his or her alcoholism under control, than if that person kept getting drunk and into trouble.)

So Ray Comfort's book might inspire followers of Yeshua to do more for God's Kingdom. But it does some harm in perpetuating false theology about being "saved from God's wrath".

In particular, it would be a terrible manual for how to talk about Yeshua to unbelieving Jews. Jewish people know quite well that God is not uptight and wrathful. When a Christian tells an unbelieving Jewish person that he or she needs to escape God's wrath, that only reinforces in the Jewish person's mind the idea that Christians and Jews must be worshipping two very different Gods, even though the Christian says otherwise.

Sunday, November 12, 2006

Tao of Yeshua: Chapter 30

30
He who leads others in following the Way will not control things by force of arms.
Those things like to turn against their wielder.
Wherever armies were stationed thistles and thorns will grow.
After a great campaign bad years will follow.
A skillful follower of the Way conquers by being resolute. He dares not conquer through violence.
He accomplishes but does not boast,
Gains victory but does not show himself,
Leads but does not flaunt his success.
He does what is necessary when there is no other choice: forced to conquer, he does not use violence.
Governance claimed through rallied strength has a temporal foundation, and thus is not of the Way, and short-lived.

Yeshua leads us to fight Satan, not people.
Soldiers have a terrible job that lacks choice.
Followers of Yeshua have the luxury of shunning evil,
and only rarely being forced to do spiritual warfare.
Trust Adonai to raise up and cast down rulers.

Nerd Warfare

I mentioned earlier that Nerf dart gun tag would be fun to do in the math department, after hours.

I should have expected that some people are much more nerdier than I am. A company makes a toy pistol that shoots balls of velcro. Now you don't need to look absurd wearing a Nerf target vest: just wear a sweater.

Of course, even nerdier people would just shoot little ninjas at each other. And the real nerds already have a USB missile launcher hooked up to their computer.

Eratosthenes and the Lemmings

I remember being taught in Elementary school that in the time of Colombus most people thought the Earth was flat. That's a myth. Eratosthenes (an ancient Greek) knew the circumference of the earth to within 1.4%.

One reason I like math is, even if it's hard, at least your teachers only teach you true things.

I recently found out that the mass suicide of lemmings is another myth, and was in fact perpetuated by Disney's murder of lemmings! Snopes has the story. (Be warned that I have FlashBlock installed, so I am not sure what advertisements this site normally displays.)

Portable Bright Lights

I wrote earlier about how a bright light really helps in a self-defense situation.

In that post I was only talking about handguns. Since then I wondered if a portable bright light might be wise to carry on its own. Here is what learned.

There are companies that make really bright self-defense flashlights. There are also companies that make bright bicycle lights.

From the SureFire site, and other reviews of their products, we learn that 65 lumens is enough, after dark, to disorient someone and perhaps help you escape conflict. This much light can be carried in a 3.2 ounce flashlight. They also sell a 200-lumen flashlight that weights 6.5 ounces.

As light technology, these lights is not terribly impressive. If I was willing to carry a pound of light and battrery, I could have ten times that much light! The SureFire brand is based on its reputation of sturdiness and reliability, not cutting-edge technology.

But I don't want to carry a pound of light and battery. Can a smaller bicycle light replace a high-power flashlight?

Definitely. But by the time you are purchasing a bicycle light of this quality you will not save any money.

The fanciest Cat Eye lights produce 85 lumens per bulb (as does the Vega bike light on the other bicycle light webiste). So the Cat Eye HL-EL530 produces light comparable to the smaller high-power flashlights and weighs about the same.

(There might even be a bicycle light I do not know about that is just as bright but the first press of its button starts its flashing mode. Studies have shown a strobe effect is optimal for self-defense.)

True, a bicycle light is not as useful as a metal flashlight if running away does not work. But for comparable money I'd rather buy one of the indestructible umbrellas I had mentioned in a different earlier post.

Eugene is bicycle-friendly and rainy. Nearly everyone owns a bicycle light and an umbrella. It would be very silly all the ways my handgun class has prompted me to think about self-defense had the end result of my purchasing... a new bicycle light and umbrella!

But I'm not going shopping yet. In Oregon there are good legal reasons not to carry a club around, even if it also works as an umbrella. I'll discuss Oregon's legal issues of self-defense in the next post in this series...



If all this talk about lights has made you wonder how many lumens are produced by the compact flourescents in your home or workplace, go here for examples.

If you are interested in the total cost of ownership for lights, and why LED lights have not yet replaced compact flourescents in homes, read the left-most article here from Compound Semiconductors Online. (Short summary: the t
otal cost of ownership for 50,000 hours is around $450 for incandescent or halogen bulbs, $350 for LED bulbs, and $150 for fluorescent bulbs).

For more information about comparing lumens and candlepower see a link here and a PDF here.

For tips about how to smash people with flashlights, see The Martialist.

James Rummel has three recent posts about why people should not trust pepper spray (unless it also contains a more potent chemical) or a taser, and what to do after you blind the attacker and flee.



UPDATE: Please do not think I am actually going to buy a self-defense umbrella. I explain why here.

Sudoku and Horse Stance

A while ago I linked to my PDA version of Sudoku. I'm still enjoying it a few times a week. For example, it's a good thing to have with me while I am waiting after an allergy shot.

Two nights ago I had an idea. My Tai Chi would improve if I practice standing in a low Horse Stance more. Perhaps if I played Sudoku on my PDA while in Horse Stance, I would be able to stay in the stance longer because I was distracted.

This worked a little. On "Easy" level my game took 4 minutes and 36 seconds to finish, and a few times I had to pause the game (turn off the PDA) and stand up, to give my legs a break. But it was definitely more interesting than only practicing Horse Stance, and added an interesting bit of urgency to finishing the Sudoku game.

Tea Infusers and Socks

This past weekend I finally figured out how to use the ceramic tea infuser that came with one of my mugs. I had been putting loose tea in it and then adding hot water. But then quite a bit of tea went down through the holes. I realized if I added the hot water first, then a lot of the tea would initially float, and have expanded in size by the time it began to sink.

It's a bit humbling to have been using a tea infuser incorrectly.

Something I had successfully figured out a few years ago was that matching socks was the worst part of doing laundry. So for that year's holiday present, I asked my wife to get me a bunch of socks that were all the same. This has worked nicely. I wear a black Towncraft "Acrylic Blend Cushion" sock: those are thick enough for Winter, not too thick for the rest of the year, and are really inexpensive at J.C. Penny.

(Doing laundry is normally one of my chores. My wife still has many varieties of socks, most of which are white socks in nearly similar pairs that are a pain to match up. But my socks' half of that work has been eliminated!)

This was a boring post, but I could not pass up the chance to write something entitled "Tea Infusers and Socks".

UPDATE: Okay, I admit it. I will need to replace some of my socks soon, so I shopped for some on Friday during one of my very rare trips to the mall. I had some trouble determining which ones they were at the store; black socks look a lot alike. Having finally identified them, I'm blogging about them so I'll have a record of which ones they are a year or two from now.

Bridges and Special Relativity

I wrote earlier about how Bridges can cause problems when measuring time.

My brother-in-law wrote back, saying that Bridges can cause problems in actually allowing travel backwards in history, beyond their effects of messing up accounting. His argument was not quite thorough, but it show me that my earlier example is deeply flawed.

In that example, I had treated Bridges as teleportation devices, similar to "transporters" from Star Trek. Transporters would cause problems when measuring time, as I described. It would also allow very blatant conflicts with causality.

(This link explains how nicely, if you understand spacetime diagrams. I'm not sure how readable spacetime diagrams are to most people. I did my undergraduate physics thesis in Relativity. I was glad to see my professor's book, at the time a draft photocopied and bound by Kinko's, is now in print and getting rave reviews.)

But Bridges are more than teleportation devices. They are actual physical connections, like the "wormholes" modern physics believes are possible but without any messy tidal forces or event horizons. So my other example was deeply flawed because the pilot could have spent most of trip standing halfway through the Bridge, with one side of his/her body on Earth and the other side on the spaceship.

Phrased most simply: Bridges can cause two locations, moving at velocities and/or accelerations, to become one frame of reference.

(In the language of special relativity: a setting with Bridges has no inertial reference frames.)

Duh. I should have seen this sooner.

Anyway, all science-fiction settings are faced with the problem that all three the following cannot co-exist:
  • the Principle of Relativity
  • a constant speed of light
  • faster-than-light travel or communication
(The Principle of Relativity states that the laws of physics behave identically in all smoothly moving inertial reference frames. In other words, if you were alseep on a train that always moved completely smoothly, upon waking you would not be able to tell if the train was currently moving or stationary until you uncovered the window.)

Many science-fiction settings discard the constant speed of light. For example, lasers create slow-moving "bolts" of photons in Star Wars and Star Trek. While this might not seem a detail of the setting related to a spaceship "drive" that moves the ship faster than light, it still renders futile most attempts to apply special relativity to the setting.

Other science-fiction settings disallow faster-than-light travel and communication. Firefly is probably an example.

For my setting it does not make sense to try to explain how special relativity shows causality paradoxes or allows traveling back in history just because the Principle of Relativity has nowhere to be applied. There are no smoothly moving inertial reference frames to work with: even to be locations for an experiment whose results differ in violation of the Principle of Relativity.

Moreover, my setting also lacks a constant speed of light! Here is a brief narrative to explain:
Imagine two very long spaceships with lots of windows pass each other in opposite directions. These spaceships are so long that a laser beam turned on at the center of a ship, traveling to one of end, takes a measurable amount of time.

One spaceship has two lasers at its exact center. These simultaneously shoot laser beams towards targets at the front and back of the ship. Within this ship, observes see the targets are hit simultaneously.

You are sitting in the other ship, in a room that has two Bridges that lead to the front and back of the other ship to give you a simultaneous view of both targets.

During the duration of the laser beam progress, you see the front of the other ship has moved slightly farther from the laser firing location and the back of the ship has moved slightly closer. Nevertheless, through the Bridges you see both targets hit by the laser beams simultaneously.

Thus the two laser beams, from the point of view of your ship, must have moved at different speeds.
In real life, the two target impacts would not be simultaneous in both locations. This has been experimentally observed with how muon travel relates to muon half-life decay: scroll down in this article for an example.

But in my setting, it would not make sense for you to observe the two target impacts as simultaneous when looking through the Bridges, but not simultaneous when looking through the windows of both spaceships. That would contradict my description of how Bridges work.

So I finally have the answer to my question. In what ways do Bridges make the setting unrealistic?

First, a beam of light must behave like any other projectile in moving faster when cast from a fast-moving source. Second, there are no frames of reference to which special relativity can apply.

(At this point a physicist might wonder how the setting would be affected since Maxwell's Equations now involve a non-constant speed of light. But since my setting is for adventuring, not laboratory work, I will ignore this issue.)

There may be more effects, but I do not now have time or brainpower left to consider them.

Wednesday, November 08, 2006

After an Election

Lane County election results are here.

I don't have time now to share any musings. Please consider this post a place-holder.

UPDATE: Well, it has been a week and I am at a loss for anything worth talking about. I am glad that the Democrats are following a somewhat moderate course. I am grateful for the chance of a "moderate Muslim" voice to be heard in politics and publicized in the media. I share others' hopeful skepticism that campaign promises about minimizing pork and extremism will be honored.

UPDATE: Am I worried about the Iraq war going badly if troops are withdrawn? Not if it happens a little at a time, as seems the most likely scenario. A change in 20,000 troops is not statistically significant.

Tuesday, November 07, 2006

In Space, No One Can Hear You Sing Happy Birthday

UPDATE: I realized later this week that the following narrative is deeply flawed. Bridges are not merely teleportation devices. For more commentary, see the newer post here.

For those blog readers not familiar with general relativity, here is a more detailed example of how Bridges allow time travel.

Note this is not "time travel" as in some stories, where people move back and forth in history. What happens is much less dramatic: objects do not age consistently in space, and Bridges let you see this happen quite clearly.

(Thanks to this site for doing the math for me. I just used their calculations for my own application.)

Consider a spaceship that leaves Earth, and accelerates at 2 g's for 100 days, until it is moving at about six-tenths the speed of light. It is heading for a destination six light-years away. But because it is moving at a relativistic speed this distance, from the point of view of the spaceship, shrinks to only 4.8 light-years.

From the point of view of the spaceship, this trip takes 8 years (4.8 divided by 0.6). From the point of view of someone watching from Earth, the trip takes 10 years (6 divided by 0.6).

Now, complicate the scenario by assuming the spaceship has a Bridge going back to Earth. In fact, you are the spaceship's pilot, but you live at home and only pilot it as a "day job". According to your watch, you spend half your time on Earth, and half you time at work on the spaceship.

When do you celebrate your birthday?

From the point of view of your friends on Earth, you do this every year from the Earth's point of view. You have ten birthdays during the journey's duration with a party on Earth involving chocolate cake. Of these terrestial celebrations, people on board the spaceship looking back at Earth through super-telescopes only see four of them (the light from the other six birthday parties is still on it's way from Earth to the destination).

From the point of view of your friends in the spaceship, you have a birthday every year from their point of view. You have eight birthdays during the journey's duration with a party on the spaceship involving vanilla cake. Of these celebrations, people on Earth looking at the spaceship through super-telescopes only see two of them (the light from the other six birthday parties is still on it's way from Earth to the destination).

So how many years older are you when you arrive at the destination? Two? Four? Eight? Ten? Or maybe 18, since you've eaten a total of that many birthday cakes?

Clearly not two or four: those are artificial constructs of the fact that light is still en route. No one in either point of view thinks you have really had so few birthdays. But the other answers are somewhat defensible.

Also, any other number greater than eight could be a defensible answer if we had yet another Bridge going to a location visited often with a third point of view. After all, some spaceship pilots might have a more active social life than you do!

Traditionally, physicists say that an object's "true" age is its age from its own point of view. But the fictional existence Bridges destroys the concept of an object "having" a meaningful point of view. Remember that you spent half your time on Earth and half on the spaceship -- neither point of view was inherently more "yours" than the other.

(Of course, you wear a watch and it measures your personal passing through time. But only things with you at all moments during that journey experienced aging as you did. Your body still gets old and wears out in the normal human way, but to other people not following you through Bridges to work and back your rate of aging seems jumpy. Watches are nice, but the fact remains that if every room in your house is actually on a different planet then you have no idea when to pay your annual property tax; the government must either give up property taxes or do taxes separately on each planet when a year passes in its point of view.)

So the existence of Bridges does not allow you to do as paradoxical a thing as going back in history to kill your own grandfather before he had any children. But it does at least mean nothing has an absolute "age". Your library books can still have a due dates, but you might have only eight days to read a book that the library thinks you checked out for ten.

One almost-final note: having a home away from home at a location moving at relativistic speeds unfortunately only means that while there your friends and family left behind perceive you as having lost time. You can't catch up on sleep by taking a Bridge someplace to get a few extra hours for rest.

This seems backwards to real physicists, but we can check by going back to our first scenario. From the point of view of the Earth, six years after you arrive at your destination all the light moving from the spaceship to the Earth during the journey will have finally arrived. At that point, from the Earth point of view, sixteen years have passed but they only saw you eat eight vanilla birthday cakes. So through telescopes your friends and family see that you age half as fast on the spaceship. But they know that's a trick of the light, because a few minutes after you arrived (six years earlier) you took a Bridge home and told them in person of your successful end to the journey.

As a final note, remember the grandfather issue? Well, if you let your own kids play on spaceships (which, after all, can move at a lot more than six-tenths the speed of light) you might be approached a surprisingly short time later by adult grandchildren you never new you had. That's not really time travel. It's just that your own kids are so bad a keeping in touch (sigh), and light moves so slowly...

Tao of Yeshua: Chapter 29

29
Some people feel forced to take all things and control them.
I have seen it cannot be done.
All things are set apart and thus contained together.
People cannot rule them.
He who acts, spoils things. He who grabs, loses things.
For things naturally rush ahead, then lag behind;
Pant warmly, then breathe coolly;
Become strong, then become feeble;
Start afresh, then decay.
Therefore the Saint accepts things as they are. He avoids forcing things. He avoids extremes.

Let Adonai own the world.
Learn to enjoy how he gives and takes away.
Help him with his plans, which are better than our own plans.

Monday, November 06, 2006

Property Tax

While I'm waiting for two cords of firewood to be delivered I'll mention something quick. (I have ministry and math work to do, but I don't want to start something and be soon interrupted.)

The current ballot has several property tax measures.
  • The library wants to renew its property tax income, and is polite enough to decrease the amount from the current level because the city has agreed to pay the difference.
  • LCC wants money. I've already written about how cost-effective community colleges are. This measure is largely acting as insurance in case state measures 41 and 48 pass, to help dampen the damage of that possible scenario. But LCC is also being polite by asking for far less than it might lose if both those measures pass.
  • The city is asking for money to buy more local park land. This is not as polite a measure, since it is being publicized as a park-development measure when it is actually primarily a land acquisition measure. I'm not sure why the measure's supporters are doing this; enough of Eugene is anti-growth that it will probably pass either way.
  • The Soil and Water Conservation District wants a little property tax money too. I don't know much about what they do, but there website makes their activities sound worthwhile and they're only asking about $15 per year.
Anyway, the point of this was supposed to be how fair property taxes are. It's just also nice that most of the places wanting a bit more are asking politely.

Income tax can be avoided if you are working illegally or get paid without the government's knowledge. But property tax is paid by everyone, whether directly because you own property or indirectly as you pay rent.

Furthermore, property tax does not have all the complications that politicans and laywers get paid to wrestle over, such as inheritances and which location(s) generated income. It uses the market element of house size to determine how much tax to pay. Since nearly half (warning: link is a boring PDF) of the property tax goes to school districts, it makes some sense that bigger families pay more than average. And since Eugene is liberal, it makes sense that wealthier families to pay more.

I hope state measures 41 and 48 don't pass. (The state government has a track record of spending money poorly, but causing lots of other people to lose their jobs does not seem an appropriate remedy.) But if they don't, and due to these property tax measues I I wind up paying more in tax instead of less next year, I won't mind. The increases are small, property tax is a nice way to do tax, and most of those asking for more tax revenue did so politely.

Star Wars Math

As long as I'm inviting people to find math/physics problems with my RPG setting, I should also share a few of Irregular Webcomic's jokes about the Star Wars setting.

Three Problems with Bridges

In answer to this post, my brother-in-law points out three issues with Bridges. I don't think any of them make the setting unsuitable for a RPG.

First is that they ruin the First Law of Thermodynamics because energy can be created freely. My brother-in-law provides a somewhat complicated example. A simpler example I'll share here would be using a Bridge pair to make a continual waterfall and then powering a water wheel with this continual waterfall.

No big deal for RPG purposes. The Second Law of Thermodynamics is important, but many RPG settings ignore it. I can do the same.

Second, a wormhole allows time travel according to general relativity. The Wikipedia article refers to a way to escape the problems presented by this issue: potentially creating a "feedback loop of virtual particles". In other words, accelerating a Bridge to relativistic velocities simply means if you bring it back near its mate they both will break.

Third, any source of free energy makes it much easier to destroy planets. An asteroid or spaceship could be inexpensively accelerated to a high enough velocity to shatter a planet it impacts.

This should change the setting so life support systems are illegal. Anyone who has a spaceship with a life support system could fly it away from their planet, eventually turn around, and fly it back fast.

Also, it reinforces why BridgeCo needs to have hidden monitoring and "back doors" built into the Bridge network. Since Bridges can be used instead of life support systems, BridgeCo needs to know the location of all ships with Bridges on them. Similarly, if someone was to travel to an asteroid by Bridge, start accelerating the asteroid, and periodically return to adjust its course, BridgeCo needs to know.

It would also make sense that detection of asteroids has improved since real-life current capabilities, and that BridgeCo has a collection of previously-accelerated asteroids at the ready. If someone else does manage to try to "crack" an inhabited planet with an accelerated mass, there may be time for BridgeCo to pick one of its asteroids moving in an appropriate direction, transport it to the scene, and "crack" the aggressor first from a direction that sends the debris away from the threatened planet.

Sunday, November 05, 2006

Caffeine Table

Being a tea drinker, living among coffee drinkers, married to a biologist, I often get asked how much caffeine is in things. Since I only keep a rough ranking in my head, I'll blog the details here so in the future I can simply refer people to it.

Data comes from the Berkeley Wellness Letter, the Mayo Clinic Website, and the Stash Tea Catalog.

Except for the espresso, chocolate, and NoDoz, all values are typical for 12-ounce drink servings.
  • Herbal Tea: 0 mg
  • Decaffeinated Tea: 1-8 mg
  • Hot Cocoa: 8 mg
  • Decaffeinated Coffee: 4-10 mg
  • Milk Chocolate (4 oz.): 4-40 mg
  • Dark Chocolate (4 oz.): 20-140 mg
  • Soda: 22-55 mg
  • White or Green Tea: 30-60 mg
  • Oolong Tea: 50-100 mg
  • Black Tea: 80-140 mg
  • Energy Drinks: 75-160 mg
  • Instant Coffee: 90-200 mg
  • Espresso (4 oz.): 180-220 mg
  • Drip Coffee: 160-300 mg
  • NoDoz (2 pills): 200 mg
The facts people normally ask about is how black tea compares to drip coffee (about half the caffeine) and how white/green tea compares to black tea (a bit less than half the caffeine).

Saturday, November 04, 2006

Base Negative Ten

Apparently November 3rd was national cliché day.

Personally, I think there should be a day where we do all our arithmetic in base negative ten. That would be sweet.

(I don't know who first thought of base negative ten. I was introduced to it by Don. It works well with arithmetic once you get used to it.)

Tao of Yeshua: Chapter 28

28
Knowing what is boastful but keeping to what is humble is being a watershed for all things.
As a watershed for all things, his experience makes virtue collect.
He is born again.
Knowing what is revealed but keeping to what is hidden is being a pattern for all things.
As a pattern for all things, his image makes virtue strong.
He returns to the infinite.
Knowing what is glorious but keeping to what does not shine is being a valley for all things.
As a valley for all things, his meekness makes virtue sufficient.
He returns to wholeness.
Vessels are carved from uncut wood by removing substance.
The Saint can use each vessel for its special purpose.
But great works do not require removing substance.

The humble accept the experiences that increase virtue.
The heavenly models how virtue is strong.
The meek can feel complete possessing only virtue.
Acquiring virtue from experiences is more valuable than acquiring skill.

Friday, November 03, 2006

The Sci-Fi Western

I only own two TV series on DVD: Kung Fu and Firefly. They are very different, but both fit the genre "Westerns".

The science-fiction setting I am planning for my role-playing game is also largely of the Western genre. So as I think about these two TV series I ponder what makes a Western a Western, but is still transferrable to a science-fiction setting.

Here is my list so far, presented somewhat in a cascading order of consequences:
  • The land around where people live is a "frontier" without governed settlements inhabited dangerous animals and people. Nevertheless, most settled locations have a few loners living on the outskirts due to temperment or profession.
  • Most adults (or perhaps only adults of one gender/class) carry portable weapons, because of the frontier's dangers.
  • Weapons technology is, at least temporarily, at a place where damage trumps armor (as opposed to knights clad in plate armor). Wounds from weapons are often fatal; a doctor near a conflict can only somtimes help the wounded.
  • Society focuses on honor as much or more than law, because so many adults are armed with dangerous weapons.
  • Big government exists, but does little, because it is annoying to big government to deal with an honor-focused, armed society. Most adults pay little in taxation and receive little in services. When big government is present it is often an interruption (installing a trade route, chasing a criminal, claiming a resource, etc.).
  • Local government exists, mainly doing law enforcement. Without the power of big government to bring wealth redistributed from a non-frontier location there is not funding for local government to do much more that the basics. (Managing utilities, travel routes, and education may or may not be consider governmental basics.)
  • Most adults belong to multi-family social groups to provide support in crisis situations (births and deaths, loss of home or livelihood, natural disasters, etc.). These social groups may be secular or religious; the various local groups may be peaceably cooperative or antagonistically competitive. Without government social services, people team up in other ways for protection from life's troubles.
  • Corruption can control a settled location, because government is small and people are reliant upon social groups. If a social group grows into a dominating organization, it can often reign unchallenged.
  • Heroes are often anti-heroes in that they remain personally troubled and/or unvirtuous but nonetheless able to save a settled location from local corruption or dangers invading from the frontier.
What am I missing?

This also sounds a lot like adventures in Edo-period Japan.

Thursday, November 02, 2006

Portable Space-Time Wormholes and Their Applications

My last post mentioned that in my RPG's science-fiction setting there is a single impossible feature that makes the setting "science fiction" instead of "speculative futurism".

This feature is the existence of Bridges, which are portable "wormholes" in space-time.

In the game's setting, a company named BridgeCo invented these in 2020. The company kept their existence secret until 2070. During the intervening 50 years, BridgeCo has explored fairly thoroughly a sphere of radius 50 light-years, using unmanned factory ships that are self-replicating as well as creating a "bridge network" that links any notable planet or other resource. The gameplay happens during the following decade, as BridgeCo severs its ties with Earth, takes with it the Earth's bravest and brightest, and oversees the initial colonization of space.

Just because the game setting says so, Bridges work as follows:
  • They must be built as a "Bridge Pair": two closed, adjacent, matching loops of metal and circuity. Activating them requires a lot of energy, and destroys most of their internal parts.
  • After activation the loops act as a portal with no space in between them. (The "back side" of each Bridge in the pair also is a portal, but usually this is covered over.)
  • Activated Bridges are metal objects and fairly sturdy, but can be broken. If they break the portal closes. There is no release of energy when a Bridge is destroyed or its portal closed (big deal, you have filled in a hole of no depth).
  • Activated Bridges can be translated in space-time, but not rotated. (For example, if a Bridge is facing down into a gravity well, such as face-down on a planet, you cannot pivot it upright.) Trying too hard to rotate a Bridge will break it.
  • Bridges may be moved through Bridges. Some applications even involve "Bridge Stairs" in which a small Bridge is carried in a sphere that allows it to rotate, and out of this Bridge slides a very long, narrow, rectangular Bridge, and out of that slides a very long, square Bridge. (For example, a spherical locket can contain a system of three portals with the largest big enough to transport a spaceship.)
  • Only BridgeCo knows how to build Bridges. The setting has alien races and alien technology, and all existing Bridges incorporate alien technology in ways that make reverse-engineering Bridges currently impossible to anyone outside of BridgeCo.
  • Both BridgeCo and other people know how to make gravitational anomoly detectors, of which even portable models can accurately detect Bridges at a range of several miles.
The existence of Bridges, and BridgeCo having space explored and accessible in a 50-light-year radius, create several applications:
  • BridgeCo has access to more than enough physical resources, of any type, for everyone. Currency would be based on worker-hours, the only commodity of which BridgeCo has demand. Other companies and organizations would purchase vital resources from BridgeCo until they are part of self-sufficient colonies. Even after self-sufficiency has been achieved, except for specialty resources (i.e., a chemical derived from a plant or animal found only on a non-BridgeCo planet, pancake syrup made from the sap of your colony's special tree) there is no normal reason any resource would be sold for more or less than BridgeCo's price.
  • For electrical power, build solar panels in orbit around a star, and run the output wires through a Bridge pair to where you need the electricity. The only disadvantages are that the star might act up, or a troublemaker with an electron telescope can detect your device from light years away.
  • For mechanical power, activate a Bridge pair and then seal shut its portal in a manner that would destroy the Bridges to undo. Now it will conduct heat but not matter. Put one Bridge on an appropriately hot planet, or in an appropriately hot orbit. Put the other in the tank of a steam engine. As before, you have power until the distant Bridge is destroyed. This setup is only detectable by troublemakers at a range of several miles. (BridgeCo sells these in several standard sizes as "Eternal Engines".)
  • If you want to travel planetside, use rotor-powered vehicles. Helicopters and fan-powered "cars" are both very practical if energy efficiency and fuel weight are not issues. Colonized planets in this setting would not have roads.
  • To travel between a planet and its satellites, any fan-powered vehicle need simply be reasonably airtight, have multiple turbines, and use Bridges to at the entrance and exit of each turbine to direct airflow so there is a net push. (In space, a ship can move simply by being a paddle boat that carries its own river of air.) Bridges also mean that spaceships need not worry about life support systems or radiating heat.
  • Few manned vehicles would be built capable of traveling between planets, let alone between solar systems. (Putting it another way, there would be many "shuttles" but very few "spaceships.)
  • Bridge routes need monitoring and security. Planets would want all off-planet Bridge travel arriving at a hub before possible travel planetside. (Thus "ports" become way-stations on moons or space stations.) The concept of a "mega-store" is changed . (For example, except for security there is no longer a practical difference between a huge mega-store and a collection of smaller stores linked by a Bridge network. Thus large corporations have incentive to own and run a planet. Unless you live someplace that has local food for sale, why shop or work at a small, neighborhood market when MegaMarket is equally close and manages security for their own planet?)
  • Unactivated Bridge pairs are potential weapons. Even by themselves they could be used to siphon away air or create a flood. Dropping a bomb (conventional or nuclear) through a Bridge pair would be a safe way to attack something, since the Bridges would be destroyed before too much of the explosion entered the attacker's side of the portal.
  • Rumors that Bridges are physically thick because each Bridge is actually two Bridges (in other words, BridgeCo builds "back doors" into each Bridge) are, of course, completely false. (Wink, wink.)
What other applications am I neglecting to think of?

UPDATE: The reason Bridges cannot rotate is to prevent them from being used within weapons. I don't want a small-looking gun magazine that holds a nearly inexhaustible supply of cartridges, a short-looking gun barrel that is actually a long rifle barrel, or a sword pommel from which springs a long blade.

Single-Fiction Science Fiction

I've decided to start blogging about the pen-and-paper role-playing game I'm designing. After all, one of the reasons I started blogging was to help process things I am thinking about.

To start out, I need to comment that we could measure how unrealistic any fictonal setting is by counting how many ways it is different from real life "just because". With this metric, only axioms are tallied, not their consequences.

For example, the Star Wars setting has, among other things, the force, lightsabers, faster-than-light travel and communication, and tractor beams. None of these are physically possible, and none are natural consequences of each other. In contrast, spaceships and aliens are futuristic but in a general sense physically possible.

Now, this is not a universally useful measure of how unrealistic a setting is. Fans of Firefly might ponder and/or appreciate how firearm technology has been almost stangnant for 500 years in that show's setting (in the year 2517 people are almost exclusively using today's guns). But my metric ignores this issue.

Nevertheless, for a role-playing game, this metric is very important.

The setting of a role-playing game needs to be intuitively understandable to the players, so they can estimate what are wise or foolish choices. This is different than settings for a novel or movie, in which some aspects of the setting can be left unexplained. In the Star Wars setting, those watching the movie do not need to understand how the force works because they do not need to make prudent decisions about when and how a character will use it.

One reason I am designing a role-playing game, as opposed to using a published one, is that the published games tend to be limiting in artificial ways that frustrate intelligent players.

Typically too many questions are unanswered, in one of two categories:
  • The game setting does not allow characters to even attempt to use various skills or objects. Or the game setting is that flexible, but the game mechanics do not specify what happens when skills or objects are used in unexpected ways. (For example, there are poisonous plants but the game's setting or mechanics does not allow making poisons out of them.)
  • Something (the force, laser weapons, magic, super-powers, etc.) works according to a rather haphazard collection of rules. It is impossible to modify these rules, even in ways the rules would find self-consistent. (For example, laser pistols must be getting a lot of energy from some sort of battery, but the game's setting or mechanics does not allow dismantling laser pistols to make use of their batteries, nor equipping the laser pistols with high-powered tactical spotlights.)
In general, the longer the rulebook(s) for a role-playing game are, the more little rules it will have and thus the less appropriate it will be for player creativity. If a player's character is simply a very finite "toolbox" of options to apply to different events then intelligent adults might as well be playing a MMORPG instead of doing pen-and-paper role-playing.

To keep the rulebook brief, the setting must be intuitive. To maximize this, I am designing a science-fiction setting with only one impossible feature (and its logical consequences).

The Skies are Bluer with a Stellated Icosahedron

Today I am very tired, because last night Eugene's weekly Wednesday night swing dancing was a special treat.

Normally there is no live music. Last night The Blue Skies Big Band, a local 20-piece swing band, played for two hours, and the dancing went on an extra hour after they stopped at 11pm. Also, a series of free lessons for "non-beginners" started up.

So I danced from 7pm until midnight. After arriving at home I had too much energy to fall asleep quickly, and wound up awake until 2am. I get up at 6am on Thursdays. So I'm tired today.

(Many of my math students were tired yesterday morning, because of partying the night before for Halloween. Today I started class by joking that now it was my turn to be tired, and my night-before party was more fun than theirs.)

Thus I postponed some grading this afternoon, and folded a stellated icosohedon. It was a relaxing and pleasant activity. Big and clear directions are here. I leave out "step 4" since this is how I learned to do this as a kid, it's faster, and it makes a sturdier construction.

Of course, some people are even fancier.

Wednesday, November 01, 2006

Handgun Update

Well, it has been two weeks since I wrote about my first experience shooting (with revolvers). Yesterday was the second "range day" of the class, and now I have used semi-automatic pistols as well.

I also mused in that post than an inexpensive pump air-gun firing biodegradable pellets might be fun to buy. I've learned more about that issue as well.

Finally, I've been exposed to more alternatives for conceal-and-carry pistols, and have some new thoughts about those in Eugene.

So, here's the update in all three topics. Then I'll share some links I've found.



Range Time

Firing a semi-automatic for taget shooting has one big advantage: it is quieter, because there are no gaps equivalent to the front and back of a revolver cylinder. The length of the barrel helps "hide" the noise of the powder burning. I mostly used a Walther P22, and even this compact gun with a very short barrel was quieter than the .22 revolver I used two weeks ago.

Also, the slide kicking back helps absorb recoil. That Walther P22 was just as easy on my hands as the heavier revolver.

The main problem with the P22 was its sights. The small barrel meant they did not work well for me. In my last post I mentioned that my skill, developed with archery, of having both eyes open while focusing only from my dominant eye was completely transferrable to gun aiming. Apparently that's not true: it is only transfers for guns with a fairly long barrel. There was a big loss of accuracy when I tried using the Walther P22 with both eyes open.

The gun was so light, and its recoil so mild, that I tried using it one-handed. This caused no loss of accuracy, no matter which hand I used, provided I kept open only my dominant eye.

I also tried using a 9mm pistol. This is supposedly a caliber with more recoil than the .38 special I did not like two weeks ago. But the pistol was heavier, and that moving slide again helped with recoil. My hands did not mind the 9mm recoil at all. However, I didn't think it prudent to try this gun one-handed.

I cannot fairly comment about the noise of the 9mm, since at this point I decided to be cautious and use earplugs as well as the "ear muffs" always used at this range. So perhaps it was as loud as the .38 special, but I did not mind its noise at all, so I doubt it.

The only disadvantage of the 9mm (besides that each cartridge costs much more than a .22lr) is that its magazines need to have stronger springs. A magazine for the Walther P22 has a button on the side you can slide down to lower the "follower" the cartridges sit on, so you can put in more cartridges without fighting spring tension. With a 9mm, you need to wedge each cartridge down on top of the other with enough force to push a stronger spring: do-able, but much more annoying than loading the wimpier magazine or using a revolver.

Pump Air-Pistols
Unfortunately, the local Bureau of Land Management does not have its maps online. I am not sure how convenient it is to bicycle or drive to a public land outside of city limits. (I'll stop by their local office on Friday.) I really doubt there is a place convenient enough that I would actually use that cheap air-pistol with its biodegradable pellets which I mentioned two weeks ago.

If I was a gun nut, I could get a pump air-pistol with variable pump. The most classic and recommended is the HB17. Three pumps allows people in rainy Oregon to practice shooting in their garage: that's enough power to ensure the pellet stays in the "trap" you build behind the target, but not enough power to hurt something if the pellet ricochets. Ten pumps would be for outdoor use at longer range. (Using a pellet gun in your garage is technically illegal, so I would not do this even if local law enforcement currently does not care about this activity.)

So if I do wind up getting an air-pistol it would be for a reason I was previously unaware. Several manufacturers sell air-pistols designed to mimic the weight and feel of a real pistol. Some of these are cheap and some are expensive. (The cheap one is this on Amazon.) If I was worried about an increase in local crime and thinking that perhaps one day I would buy a real gun, it would be an inexpensive way, in the meanwhile, to practice not only aiming but grip and trigger pull with a realistic piece. (As before, if I had more friends that thought pellet shooting would be fun, a cheap pump air-pistol would be nice to have. But now I would spend a little bit more to get one that also provided more transferrable practice.)

Carry Pistols
During the past two weeks I have also learned more about guns designed for concealed carry.

[UPDATE: Having learned more about the .22 Magnum cartridge, I'll no longer classify the tiny NAA guns as for people trying to run away. They just better be great shots with only five bullets to work with! See more here.]

A company named North American Arms makes tiny guns for agreeable people who run away.

Five shots with a .22 cartridge can only be expected to slow down an attacker. A .22lr bullet fired from a miniature barrel has only half the recommended ballistic gelatin penetration. Also, it is probable all five shots will not hit: adrenaline will hinder aim, and such a tiny gun will not have a grip that fits your hand well, nor a barrel long enough to aim with precision unless you have practiced a whole lot.

This is a gun for people who would cooperate with a mugger, and would run out the back door if they heard someone in their house at midnight. But if reasonable attempts to flee fail and the aggressor also happens to run as fast as you do, perhaps you can slow them down.

Loaded with a .22 frangible cartridge (a short-range bullet designed for shooting snakes and rats, which becomes tiny lead shot upon impact) this gun becomes so wimpy that a thick winter coat might neutralize it. A miss would do little damage to whatever it hit across the street. But it might slow down a human pursuer, or deter an attacking dog.

As a .22 it would be inexpensive and comfortable for practice (although loud for a .22). As something so tiny, it could be carried in any pocket, any time.

I'm not about to get one. As I keep repeating, Eugene is very safe.
Three quick tangents.

I've requested statistics specific to crime between strangers (excluding a lot of the city's crimes, which are within the meth culture or are domestic violence), preferably for more years that the Eugene Police website provides. I'll share them once the police reply.

Also, remember my unsafe friends? The neighborhood that contains a sizeable amount of student housing is where a lot of the city's crime happens, largely because of meth-related crimes. Here is its map for comparison: not very safe.

Finally, Eugene was included in the recent FBI study on the nation's safest and most dangerous cities, but was not in the top 25 of either category.
But it was interesting to see that a company actually designs a tiny gun for the "preferrably agreeable or fleeing" crowd.

Links
First, three sites about the "gun debate".
  • Here is a website providing an exhaustive compliation of gun use statistics. However, the presentation is biased in many ways. (For example, pistols make poor home defense weapons, as I have mentioned before, but this report ignores this issue.)
  • Here is a website that helps point out the biases in the previous website's mindset. But it has its own bias and often uses poor statistics from low-quality studies that have long-ago been debunked.
  • Here is a two-part article with neither exemplary statistics nor unbiased arguments, but it does address some issues raised by the second website.
Next, my favorite gun-related site: the Box O'Truth. A retired fellow tests out all the gun-related things popularly pondered. Can pistols really destroy padlocks like in the movies? How many textbooks does it really take to stop a bullet? Do frangible cartridges stop being wimpy at higher caliber? Etc. Great photos.

Then my favorite post so far about philosophy and gun ownership. (I have a hard time searching for articles on this topic. Please share good ones you know of!)

Finally, two images: a bumper sticker about ammunition recycling and a PDF target generator website.

UPDATE: I've learned that Lane County has about 10,800 concealed handgun permits. Census data shows me that's about 4% of adults over 21, and about 7.5% of housing units. Since only people aged 21 or over may be issued a concealed handgun permit, it's no wonder that crime is much higher around college student housing.

UPDATE: Okay, if I guess a real gun nut would use this is his or her garage.

UPDATE: Another printable target, this time a JPG image instead of a PDF, and with commentary based upon how you miss the center.