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#1
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| Let's say I am playing a game of paintball and I shoot at someone's back as they are running away from me. They are within range and the paintball hits them. However, a recent puzzle I read about claims that's mathematically impossible, because say he's thirty feet away and running away. The paintball must travel thirty feet to reach him, but during the time it traveled thirty feet, he has moved farther away. Let's say he's moved two inches further. So, now the paintball must travel two inches more--but in that time my victim has moved still further away. Each time the paintball travels to where my target was, he has moved out of position. This could supposedly be calculated out to infinity with the paintball never reaching the target. But it does. So what's wrong with the scenario? It's probably something simple but I don't get it. |
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#2
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| Dear Ernie Sty: "Ernie Sty" <fake_email@yahoo.com> wrote in message news That is Zeno's paradox, it dates from before the birth of Christ, and it was a "prank" on one particular school of philosophical thought. Solve for when the person running and the paintball are coincident. Don't mess around with infinite sums where it is not needed. David A. Smith |
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#3
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| Dear Ernie Sty: "Ernie Sty" <fake_email@yahoo.com> wrote in message news That is Zeno's paradox, it dates from before the birth of Christ, and it was a "prank" on one particular school of philosophical thought. Solve for when the person running and the paintball are coincident. Don't mess around with infinite sums where it is not needed. David A. Smith |
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#4
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| On Apr 23, 6:58 pm, "Ernie Sty" <[Only registered users see links. ]> wrote: Look up the paradoxes of Zeno. This is effectively the same thing as proving that 1/2+1/4+1/8+.... doesn't add up to infinity, it adds up to 2. In short, the answer is the time that it takes for each successive step is smaller and smaller. And an infinite series of smaller and smaller time steps does not necessarily add up to an infinite amount of time. Though the analysis above makes it look like an infinite series of steps (it is), it is still a finite amount of time. PD |
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#5
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| On Apr 23, 6:58 pm, "Ernie Sty" <[Only registered users see links. ]> wrote: Look up the paradoxes of Zeno. This is effectively the same thing as proving that 1/2+1/4+1/8+.... doesn't add up to infinity, it adds up to 2. In short, the answer is the time that it takes for each successive step is smaller and smaller. And an infinite series of smaller and smaller time steps does not necessarily add up to an infinite amount of time. Though the analysis above makes it look like an infinite series of steps (it is), it is still a finite amount of time. PD |
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#6
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#7
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#8
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| "PD" <[Only registered users see links. ]> wrote in message news:1177435427.117981.323270@r35g2000prh.googlegr oups.com... I don't understand, but you seem to have explained it very simply. I will think about your explanation for a while and I suspect I'll get it eventually. Thank you for explaining it. Mathematically, will the succession of fractions you mentioned ever really equal 2? Or will it go on infinitely without ever reaching 2? Also, is it possible that space can't be divided into smaller and smaller sections infinitely; that at some point there is a "smallest possible unit" of space? |
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#9
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| "PD" <[Only registered users see links. ]> wrote in message news:1177435427.117981.323270@r35g2000prh.googlegr oups.com... I don't understand, but you seem to have explained it very simply. I will think about your explanation for a while and I suspect I'll get it eventually. Thank you for explaining it. Mathematically, will the succession of fractions you mentioned ever really equal 2? Or will it go on infinitely without ever reaching 2? Also, is it possible that space can't be divided into smaller and smaller sections infinitely; that at some point there is a "smallest possible unit" of space? |
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#10
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| Dear Ernie Sty: "Ernie Sty" <[Only registered users see links. ]> wrote in message news:[Only registered users see links. ]... .... When you get to the molecular level, "space" is a really poor concept. It makes sense to talk about "average bond lengths", but you don't actually find that exact bond length. Space and time are like "population mean". Makes good sense when you have a large statistical population, but means nothing for a population of "a few". David A. Smith |
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