One mile from __shore__

# Narj

"Ready, shoot... Aim!"

### Gun solution?

My car is insured for half a million bucks against the chance that it hurts someone.

How about a similar bond held against the chance that a gun does the same? Levied as a use tax at the point of sale, and returned upon transferal, it would spread liability across the appropriate population, compensate victims, and motivate owners to guard carefully against "theft and loss."

How about a similar bond held against the chance that a gun does the same? Levied as a use tax at the point of sale, and returned upon transferal, it would spread liability across the appropriate population, compensate victims, and motivate owners to guard carefully against "theft and loss."

### Kaigun: Steampunk Chapter 7

### Making Steam

Andrei Michal found Sergei's dried up little corpse rolled in blankets, only a little mouse-eaten. He looked satisfied, as though he'd died on a full stomach with all the kids married and next year's barley crop safely in the ground. Andrei hoped it was true, but he doubted it. He couldn't spent too much time worrying about that though, because of the wonderful machine! After running back, shouting to wake everyone up and tell them about the body, and the museum, and the things he'd seen, he had mostly been shushed. They dragged out the old curator ("because nobody wants to sleep with a dead man") and mostly went back to sleep. One of the girls, Anjin, seemed a little bit interested in all the little books and the shiny control panels, and Dmitri was roused enough to at least look around, though he found the aircraft more interesting.

Not Andrei. He knew what he was looking at was just right, just modern enough to be potent, just archaic enough to be operable in the current sorry state of the Union of Soviet Socialist Republics. Those fancy fighter jets would never fly again, never even find the exotic fuel for their finicky bellies, or a pilot with training to know which button to push but this thing, this "Sovietski Kaigun," this was obvious in the same way a blunt instrument advertised it's purpose. A rolling fire-powered monster intended to fight old wars against moldering foes no longer ominous, it could be run by a starving band of villagers, he knew it.

"And this," thought Andrei Michal, patting the 14 foot long steam rifle, "this is obvious too. It is a chicken gun."

Andrei curled up not so far from where he'd found the old curator, and fell asleep alternately wondering how to awaken the somnolent Kaigun, and imagining the stupendous pot of soup he would make afterwards. Where would they get enough onions?

The next day, there was some interest, peaking after Dmitri happened across the wine cache, and tapering rapidly thereafter as people, despite the best intent to ration, drank rather more than they should on empty bellies, and after so many weeks without any liquor to stay in practice. Still, Russian peasants (and they now thought of themselves as that, though only privately) are nothing if not good drinkers, and by late afternoon, an earnest if raucous committee deigned to stand around the Kaigun, poking at levers, smearing the protective red grease, and thumbing the manuals. Everyone considered the monster, a museum piece after all, to be surely disabled, and if by imperceptible means, well, it was plainly complicated enough to have had a key valve removed, concrete poured in some essential plumbing, or a critical cotter pin pulled, even if nonesuch could be found by a band of mere vagabonds.

Then Anjin found the precise accountant's inventory of projectiles, and it's obvious discrepancy, and then tiny scratches around the otherwise factory-perfect muzzle of the starboard rifle, itself elevated a couple of degrees out of it's caging mechanism, and someone noticed the Kaigun was aimed bodily at two wide rolling hangar doors, padlocked and rusting now. Every attitude changed.

Outside, beyond the doors, across a road and a dilapidated park was an ancient sculpture, Soviet in style, abstract and curved, welded steel evoking the flag's hammer and sickle. ...with a two foot hole blown through the sickle's decimeter blade as though by some monstrous torch. Nothing much could be found of the supposed "bolt" but standing in the notch of a collapsed cinderblock wall another 20 meters beyond the sculpture, one could look back, through the melted hole and watch the hangar door rolling slowly open (the locks having been opened with keys from the curator's breast pocket) and unveiling the rifle's maw as it did.

Now, people were interested, galvanized. Plans were laid, Andrei congratulated, more wine drunk, vengeance plotted, threats trumpeted into the sunset, Andrei carried around the museum in triumph, dancing, even and yet more drinking and then sleep with headaches sure to follow.

### Cosmology & Einstein

First, here's the link to my first post, talking about time vs speed of light. THE Horizon.

Next, here are some neat facts.

Here's the spreadsheet of cool facts from Brian Cox's lecture right before they found Higgs. That lecture had in it the following. First, everything's either the standard model or relativity and we can't tie them together yet. Then a divergence into the universe, introducing the Hubble constant, which is 1/13.4billion yrs, so that's roughly when everything was simultaneously here, i.e. the age of the universe. It's derived from known brightness of some supernovae. (distance) and red shifts (velocity) of everything we see. Assuming the redshift of the CMB is on that line, it's 13.4 billion years old. BTW, CMB is uwave frequency now, was literally red at first. After H0, Cox talked about particles. up,down, neutrino, electron being all you need. Two more columns of heavier versions, then photon & other force carriers. Nothing for gravity. Higgs field posited, the particle being very heavy & thus requiring high energy to make. After the switch to gravity & Einstein, he noted the light clock & Lorentz contraction as a consequence.

Well, that's just a lot of notes from the show. Then I started reading about relativity a bit, simultaneity & constancy of c. The first question is, what about a light-speed game of ping-pong, where the table is aligned with the velocity? The metaphor's imperfect (air hockey would be better) because there's no hypotenuse here. Instead just imagine the balls going straight back and forth. In the light clock meanwhile, photons go up and down between mirrors, perpendicular to v,"tick, tock." Onboard a speeding train, let's say the clock (tic,toc) and the game (ping pong) are perfectly synchronized, one second travel each way for both the pendulum and pingpong ball. That's my view aboard the train. What about to you, standing by the tracks?

I've got 3 things to discuss and quite difficult without pictures but here goes...

First, the standard light clock explanation. To you, the clock photons travel a diagonal, the hypotenuse of a triangle. (For ease of computation, say v =c/2 and a light-second's worth of distance is d, henceforward.) That lets you calculate, based on the root(5)* distance traveled after a tick and a tock, "the clocks on that train must be running slow if they think that's a second!" From the ratio of sqrt(5) to 2 you calculate the ratio of time slowing aboard the train.

{*This last is wrong, t' = t/sqrt(1-v^2/c^2), says many sources. I didn't immediately see my error, but it calculates to 15%, not 12% so I'll use that below. Update: wikipedia clarifies the answer, which is that the base leg is shortened because it's t', the quicker-ticking observer's clock from which frame we make this measurement, while the beat that determines the distance traveled is at the slower moving clock rate. Anyway, it complicates the algebra slightly.}

Second, the train has to shrink. That's because the pingpong and the clock are synchronized. The forward travelling pingpong ball also takes 1 sec (onboard time) and being synchronized, 1.15sec, observer time to cross the table one way, from "ping" to "pong" so to speak. Unlike the pendulum, those ping-pong photons will not travel the whole hypotenuse so to stay synchronized with the "tic-toc" of the clock the vehicle must stretch or shrink along the velocity direction so that the pingpong ball hits the paddle just at the "tock." With v = c/2 the numbers work out nicely. In a second's time, the ball travels the distance of the table, but the train has meanwhile moved half a second ahead. It will take two seconds for a photon to hit the second paddle, one to cross the table, and one more to catch up to the train. Only, it will actually be 2x 1.15sec since we're working in observer time where I've already noted the train clock is running ~15% slow. Whoops, a paradox! ...it

Now my third observation stumped me: it seems sure the return of the ping-pong ball back across the table will happen in an instant, since the train, and the "ping" paddle aboard it, is rushing forward to meet it. Remember the essence of this experiment is that the balls (being photons) travel at c w.r.t. all observers. Now the observer sees relative velocity between ball and paddle of 3c/2, and distance ~d/2, so elapsed t will be ~d/3c, or just 1/3 sec! (approximation 'cause I'm temporarily leaving out the 15% time dilation for easier calculating) How's

In the second it takes from ping to pong, the train moves half a light second (d/2) down the tracks and so it will take an extra half second for the "pong" to reach us. Along the way, the second "ping" is added because after all the report of pong is a photon and the ball is just as fast, so "ppionngg" will arrive all at once. Since I know the train's moving I expect each successive second's data to arrive an extra half second late. All together I hear ppionngg every 2.3 seconds, one sec for travel time of the ball, + one second's further train "entfernung" (distancing itself from me); so I guess it does all work out.

Next, here are some neat facts.

Here's the spreadsheet of cool facts from Brian Cox's lecture right before they found Higgs. That lecture had in it the following. First, everything's either the standard model or relativity and we can't tie them together yet. Then a divergence into the universe, introducing the Hubble constant, which is 1/13.4billion yrs, so that's roughly when everything was simultaneously here, i.e. the age of the universe. It's derived from known brightness of some supernovae. (distance) and red shifts (velocity) of everything we see. Assuming the redshift of the CMB is on that line, it's 13.4 billion years old. BTW, CMB is uwave frequency now, was literally red at first. After H0, Cox talked about particles. up,down, neutrino, electron being all you need. Two more columns of heavier versions, then photon & other force carriers. Nothing for gravity. Higgs field posited, the particle being very heavy & thus requiring high energy to make. After the switch to gravity & Einstein, he noted the light clock & Lorentz contraction as a consequence.

Well, that's just a lot of notes from the show. Then I started reading about relativity a bit, simultaneity & constancy of c. The first question is, what about a light-speed game of ping-pong, where the table is aligned with the velocity? The metaphor's imperfect (air hockey would be better) because there's no hypotenuse here. Instead just imagine the balls going straight back and forth. In the light clock meanwhile, photons go up and down between mirrors, perpendicular to v,"tick, tock." Onboard a speeding train, let's say the clock (tic,toc) and the game (ping pong) are perfectly synchronized, one second travel each way for both the pendulum and pingpong ball. That's my view aboard the train. What about to you, standing by the tracks?

I've got 3 things to discuss and quite difficult without pictures but here goes...

First, the standard light clock explanation. To you, the clock photons travel a diagonal, the hypotenuse of a triangle. (For ease of computation, say v =c/2 and a light-second's worth of distance is d, henceforward.) That lets you calculate, based on the root(5)* distance traveled after a tick and a tock, "the clocks on that train must be running slow if they think that's a second!" From the ratio of sqrt(5) to 2 you calculate the ratio of time slowing aboard the train.

{*This last is wrong, t' = t/sqrt(1-v^2/c^2), says many sources. I didn't immediately see my error, but it calculates to 15%, not 12% so I'll use that below. Update: wikipedia clarifies the answer, which is that the base leg is shortened because it's t', the quicker-ticking observer's clock from which frame we make this measurement, while the beat that determines the distance traveled is at the slower moving clock rate. Anyway, it complicates the algebra slightly.}

Second, the train has to shrink. That's because the pingpong and the clock are synchronized. The forward travelling pingpong ball also takes 1 sec (onboard time) and being synchronized, 1.15sec, observer time to cross the table one way, from "ping" to "pong" so to speak. Unlike the pendulum, those ping-pong photons will not travel the whole hypotenuse so to stay synchronized with the "tic-toc" of the clock the vehicle must stretch or shrink along the velocity direction so that the pingpong ball hits the paddle just at the "tock." With v = c/2 the numbers work out nicely. In a second's time, the ball travels the distance of the table, but the train has meanwhile moved half a second ahead. It will take two seconds for a photon to hit the second paddle, one to cross the table, and one more to catch up to the train. Only, it will actually be 2x 1.15sec since we're working in observer time where I've already noted the train clock is running ~15% slow. Whoops, a paradox! ...it

**take that long because it's got to stay synchronized with the clock! It's got to get there in just one (dilated) second. This is why Einstein (or Lorentz) said the train has to shrink. From the observer's perspective, we calculate the unknown distance from known time and speeds, yielding that the length of the squished table d(squished) = (c-v)*1.118 which tells us the train has to shrink to just 18% more than***can't***it's "real" (at-rest) length. Ok, fine. Mind bending, but I get it.***half*Now my third observation stumped me: it seems sure the return of the ping-pong ball back across the table will happen in an instant, since the train, and the "ping" paddle aboard it, is rushing forward to meet it. Remember the essence of this experiment is that the balls (being photons) travel at c w.r.t. all observers. Now the observer sees relative velocity between ball and paddle of 3c/2, and distance ~d/2, so elapsed t will be ~d/3c, or just 1/3 sec! (approximation 'cause I'm temporarily leaving out the 15% time dilation for easier calculating) How's

*that*gonna synchronize with the tick-tock? Last night talking with Miles I convinced myself it was a consequence of the time when I make the observations, which time is itself obviously subject to lightspeed delays. Now, I'm just confused again. However, check this out:In the second it takes from ping to pong, the train moves half a light second (d/2) down the tracks and so it will take an extra half second for the "pong" to reach us. Along the way, the second "ping" is added because after all the report of pong is a photon and the ball is just as fast, so "ppionngg" will arrive all at once. Since I know the train's moving I expect each successive second's data to arrive an extra half second late. All together I hear ppionngg every 2.3 seconds, one sec for travel time of the ball, + one second's further train "entfernung" (distancing itself from me); so I guess it does all work out.

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