throopw@rtp47.UUCP (Wayne Throop) (08/18/85)
The article I am referencing has a title request, and a request for an inconsistancy resolution. I don't remember the title, but I can help with the inconsistancy. To condense the original: > This discussion reminds me of an Isaac Asimov story about two > scientists; [...] The quick one invents a device for nullifying gravity, > [...] places the device on the center of a pool table over a hole cut in > the surface. [...] the quick guy invites the slow guy to demonstrate > [the] great invention he has by shooting a pool ball [...] through the > null-gravity field [...] The slow guy thinks a bit, then makes a bank > shot so the ball is headed directly at the fast guy as it enters the > field. [...] the quick guy has a hole punched through him by the ball > [which] stayed put while the rest of the world whooshed by > > Two questions: Does anyone remember the title of this story? I beleive it had to do with the plot, and was something like "Fools rush in...", but I wouldn't bet the mortgage. > How could the slow guy predict which way the ball accelerated? He didn't have to. You've mis-remembered the reason that the ball zapped the quick guy [the experimentalist], and the reasoning that the slow guy [the theoretician] used to predict this behavior. **** SPOILER WARNING (for those who want to read it for themselves) **** The story was told from the viewpoint of a third fellow, who observed the incident and smelled a rat. The reason the pool ball took off like a bullet was that it was made *massless* by the gravity-nullifying device. Massless particles *must* travel at the speed of light, hence the ball takes off at lightspeed. Upon leaving the gravity-free zone, the transition back to massy-ness, and back to sane velocity (for massy particles) is incomplete, and the ball still has near-light speed. In the story, there is foreshadowing of this, and after the fact this effect is used to manfacture energy (by blowing small particles into the field and capturing the radiation that results yeilding heat, driving turbines, etc, etc). Now then, in the story, the slow fellow had figgured out what was going on before making his shot. He realized that a particle going into the field "ought to" leave the field along the same line, but accelerated to near-lightspeed. The third party suspected him of this, but the slow guy covered his tracks well, by promoting the theory that the exit path was random. The third party was the only one who noticed that the ball went *into* the field aimed directly at the quick fellow's heart, and he couldn't get anybody else to believe him. Sadly, it seems to me that there is a problem with Asimov's reasoning. Such a field "should" act on the elementary particles that *make up* the pool ball, not on the pool ball as a whole. Thus, since the particles that make it up are vibrating every-which-way (in thermal motion), the ball should have *exploded*, leaving a sizeable crater, rather than turning into a pool-ball-diameter beam of hard radiation. Ah well, a fairly nice short story with a twist ending, even so. > Jim Petrick (petrick@lll-crg.ARPA) -- (Note that the followup-to is changed to net.sf-lovers only.) -- Wayne Throop at Data General, RTP, NC <the-known-world>!mcnc!rti-sel!rtp47!throopw
mangoe@umcp-cs.UUCP (Charley Wingate) (08/22/85)
In article <149@rtp47.UUCP> throopw@rtp47.UUCP (Wayne Throop) writes: >The story was told from the viewpoint of a third fellow, who observed >the incident and smelled a rat. The reason the pool ball took off like >a bullet was that it was made *massless* by the gravity-nullifying >device. Massless particles *must* travel at the speed of light, hence >the ball takes off at lightspeed. Upon leaving the gravity-free zone, >the transition back to massy-ness, and back to sane velocity (for massy >particles) is incomplete, and the ball still has near-light speed. In >the story, there is foreshadowing of this, and after the fact this >effect is used to manfacture energy (by blowing small particles into the >field and capturing the radiation that results yeilding heat, driving >turbines, etc, etc). >Now then, in the story, the slow fellow had figgured out what was going >on before making his shot. He realized that a particle going into the >field "ought to" leave the field along the same line, but accelerated to >near-lightspeed. The third party suspected him of this, but the slow >guy covered his tracks well, by promoting the theory that the exit path >was random. The third party was the only one who noticed that the ball >went *into* the field aimed directly at the quick fellow's heart, and he >couldn't get anybody else to believe him. >Sadly, it seems to me that there is a problem with Asimov's reasoning. >Such a field "should" act on the elementary particles that *make up* the >pool ball, not on the pool ball as a whole. Thus, since the particles >that make it up are vibrating every-which-way (in thermal motion), the >ball should have *exploded*, leaving a sizeable crater, rather than >turning into a pool-ball-diameter beam of hard radiation. Ah well, a >fairly nice short story with a twist ending, even so. A more serious problem is that this violates mass-energy conservation rather severely. Unless you're pumping enough energy into the thing, when the thing comes back out, either the velocity must go away or you've got to lose a lot of mass. (you also need it to get rid of momentum.) An object that can accelerate a cue ball to near lightspeed is sopping up a LOT of energy. It's also hard to imagine what happens to a bunch of massless particles having both color and charge. Charley Wingate
chris@umcp-cs.UUCP (Chris Torek) (08/22/85)
A hint: the story was *not* called "Dirty Pool". (Actually, I don't remember the real title---my best guess is "The Billiard Game"---but I do remember Asimov remarking that "Dirty Pool" was suggested to him by a reader, but he decided against changing the title anyway.) -- In-Real-Life: Chris Torek, Univ of MD Comp Sci Dept (+1 301 454 4251) UUCP: seismo!umcp-cs!chris CSNet: chris@umcp-cs ARPA: chris@maryland
hester@uci-icse (08/22/85)
From: Jim Hester <hester@uci-icse> The title of Asimov's short story dealing with two men, a gravity nullifier, and a billiard ball as a murder weapon was "The Billiard Ball", and was printed in two collections of Asimov's short stories: "The Best of Isaac Asimov" and the more famous "Asimov's Mysteries". Minor correction: The 'slow guy' was the scientist (a theoritician), and came up with the mathematics for describing gravity. The 'quick one' was just a good field engineer who had become rich implementing the slow guy's ideas. He was no scientist. In fact, he had no understanding of the machine he built. It never occurred to him to wonder about the ultra-violet light that the null-G field emitted (caused by air wandering into the field, coming out at lightspeed, and burning in the surrounding air), explaining it to the crowd simply as a side-effect of the field. The slow theoretician managed to quickly deduce the cause of the light and used it to give the flashy engineer what he had coming, using the engineer's own non-understood machine as the weapon.
john@hp-pcd.UUCP (john) (08/23/85)
<<< < < I don't remember the title The Billiard Ball from his Asimov's Mysteries collection (Although he almost called it "Ditry Pool" < Sadly, it seems to me that there is a problem with Asimov's reasoning. < Such a field "should" act on the elementary particles that *make up* the < pool ball, not on the pool ball as a whole. Thus, since the particles < that make it up are vibrating every-which-way (in thermal motion), the < ball should have *exploded*, leaving a sizeable crater, rather than < turning into a pool-ball-diameter beam of hard radiation. Ah well, a < fairly nice short story with a twist ending, even so. < Even if you ignore thermal vibration it doesnt make sense. The point of a rolling pool ball that would first strike the field has a velocity vector that is straight DOWN into the pool table. The ball should start "Peeling" itself off into a beam of particles that would start off going down and move up and forward. When the axis of the ball hit the field it would punch straight through but the rest would be quite a mess. You can explain the balls actions if you assume that the field barrier acts more like an elastic membrane than a solid sheet. When a bit of matter strikes the field it depresses the surface without breaking it. After the matter is fully inside the original boundry the field will close around behind it leaving it in a bubble within a closed field. We all know that a closed antigravity field (Like Nivens Statis Fields) cannot exist within another closed field so the inner one will instantly cease to exist. At that time the matter instantly achieves light speed. John Eaton !hplabs!hp-pcd!john