SF story featuring oscillation?
Kieran Mullen
I use science fiction in my Intro Physics class. I've used "The
Cold Equations" to discuss Newton's Laws of Motion, and "Neutron Star"
to discuss gravity and tidal forces. I'll use one of the "Tales of
the White Hart" to discuss potential energy.
I can't think of any story which focuses on simple harmonic
oscillation, e.g. a spring or the like. I'm looking for a story where
the science or math of oscillation is important; if I just wanted
references to oscillation I could go with "Foucault's Pendulum" or
something :-).
Thanks,
Kieran Mullen
Mike Dworetsky
news:2fa2b7a8-f362-48f0...@d34g2000vbm.googlegroups.com...
There's a Gregory Benford novel in the series about humans/cyborgs in the
far future, in which one of them falls into the axial core of a planet and
freefalls from surface to centre, back up to the other pole, and back again.
Even includes a formula for the cycle period. (Same as the shortest
circular orbital period IIRC.) Sorry I can't recall title.
--
Mike Dworetsky
(Remove pants sp*mbl*ck to reply)
Robert Sneddon
<2fa2b7a8-f362-48f0...@d34g2000vbm.googlegroups.com>,
Kieran Mullen <kie...@ou.edu> writes
"The Men and the Mirror" by Russ Rocklynne. Pendulum motion and
precession in one.
--
To reply, my gmail address is nojay1 Robert Sneddon
Butch Malahide
> In message
> <2fa2b7a8-f362-48f0-8dbe-83c9570d9...@d34g2000vbm.googlegroups.com>,
> Kieran Mullen <kie...@ou.edu> writes
>
>
>
> > I use science fiction in my Intro Physics class. I've used "The
> >Cold Equations" to discuss Newton's Laws of Motion, and "Neutron Star"
> >to discuss gravity and tidal forces. I'll use one of the "Tales of
> >the White Hart" to discuss potential energy.
>
> > I can't think of any story which focuses on simple harmonic
> >oscillation, e.g. a spring or the like. I'm looking for a story where
> >the science or math of oscillation is important; if I just wanted
> >references to oscillation I could go with "Foucault's Pendulum" or
> >something :-).
>
> "The Men and the Mirror" by Russ Rocklynne. Pendulum motion and
> precession in one.
That's the first one I thought of, but it's not simple harmonic
oscillation; it will have to wait till Prof. Mullen gets to the
section on *damped* oscillation. The damping caused by the "damnably
small amount of friction" is a plot point; if not for that, they would
slide all the way back up to the rim.
Sea Wasp (Ryk E. Spoor)
One of Saberhagen's Berserker stories in the "Brother Berserker" series
featured a Galileo/DaVinci analogue and a version of Foucault's Pendulum.
--
Sea Wasp
/^\
;;;
Live Journal: http://seawasp.livejournal.com
lal_truckee
It's a YASID since I can't remember much but the oscillation, but
there's a story about a nano black hole falling into the earth and
orbiting beneath the surface "vertically" i.e. oscillating. Much
consternation ensues until someone calculates the growth rate of
something so small that the atoms it falls through are as distant
galaxies - it won't eat the earth until long after the heat death of the
sun IIRC.
P.S. We can date this story either by my fallible memory of reading it
"a long time ago," or by noting it has to be before Hawkins informed us
that nano black holes would evaporate.
Have at it YASID space rangers.
Johnny Tindalos
news:HNCdncwnqo6_k1DX...@bt.com:
That's Killeen Bishop, in _Tides of Light_.
Wins the prize for Best Use of Cosmic String...
Kieran Mullen
Actually, I plan to use that later in discussing angular momentum.
The Ross Rocklynne story screws up conservation of angular momentum.
The issue was revisted in Geoffrey A. Landis's short story "The Man in
the Mirror" in which the hero survives by treating the problem as a
giant "half-pipe" for a skateboarder. I plan to use that when I
discuss conservation of energy. It's a good problem in which
potential and kinetic energy are swapped in pumping up the trajectory.
One possibility is a Niven story wherein a character releases a mini-
black hole on Mars. It oscillates through Mars and comes back just in
time to kill his rival by rather acute organ disruption. (I'm not
posting a YASID on that one since I think I can track it down).
However, I had already used Niven once in the course.
A good story on resonance would also be appropriate since we will
discuss driven oscillation as well. Any ideas?
Kieran Mullen
alien8er
_The Missing Matter_ by Thomas R. McDonough has Our Intrepid Heroes
bobbing back and forth through a sheaf of alternate realities, though
they don't realize it for a while; they think they're just wandering
aimlessly through one world after another.
Reference is made to "the stars that oscillate up and down through
the plane of the Milky Way galaxy", and some of the physical constants
are different in the other realities. In those where Planck's constant
is larger the protags can think better, though they have to tinker
with their own body chemistry to stay alive.
While they're thinking better, one of them figures out the cyclic
nature of their journey, that it's simple harmonic motion (with
equations!), and how to figure out when to jump off the ride in order
to get home.
The edition I have is 305 pages; the mathy bit is on pp. 293-294.
( Also, for the benefit of whoever posted the relevant question more
than a year ago, the book features a benign Islam as the dominant
cultural/religious milieu.)
Mark L. Fergerson
Mike Ash
lal_truckee <lal_t...@yahoo.com> wrote:
> It's a YASID since I can't remember much but the oscillation, but
> there's a story about a nano black hole falling into the earth and
> orbiting beneath the surface "vertically" i.e. oscillating. Much
> consternation ensues until someone calculates the growth rate of
> something so small that the atoms it falls through are as distant
> galaxies - it won't eat the earth until long after the heat death of the
> sun IIRC.
>
> P.S. We can date this story either by my fallible memory of reading it
> "a long time ago," or by noting it has to be before Hawkins informed us
> that nano black holes would evaporate.
The following is not meant to be critical in any way, but is rather
genuine curiosity.
Why do so many people misspell Hawking's name? I so frequently see
Hawkin or Hawkins or Hawkings or similar things. It seems like a pretty
easy English name, easier to spell than Einstein. And yet I never see
Einstein misspelled, but it seems that any reference to Hawking is as
likely to be spelled wrong as right.
--
Mike Ash
Radio Free Earth
Broadcasting from our climate-controlled studios deep inside the Moon
Ted Nolan <tednolan>
Of course *the* SF story on oscilation is the Van Vogt one that was grafted
onto _Weapon Shops of Isher_, though the thought of teaching science using
Van Vogt boggles..
Ted
--
------
columbiaclosings.com
What's not in Columbia anymore..
Paul Ciszek
In article <2ae636bf-163c-4992...@d4g2000vbm.googlegroups.com>,
Kieran Mullen <kie...@ou.edu> wrote:
>
>One possibility is a Niven story wherein a character releases a mini-
>black hole on Mars. It oscillates through Mars and comes back just in
>time to kill his rival by rather acute organ disruption. (I'm not
>posting a YASID on that one since I think I can track it down).
>However, I had already used Niven once in the course.
"The Hole Masn", and no, the hole does not go and come back. How could
you make sure your victim was in the right place hours later, anyway?
No, the hole gets the captain on the first pass.
For resonance, there was a nice bit in Clarke's _The Fountains of Paradise_.
But it is only a minor detour.
--
Please reply to: | "Any sufficiently advanced incompetence is
pciszek at panix dot com | indistinguishable from malice."
Autoreply is disabled |
Tim Bruening
Kieran Mullen wrote:
> On Oct 7, 4:47 pm, Robert Sneddon <f...@nospam.demon.co.uk> wrote:
> > In message
> > <2fa2b7a8-f362-48f0-8dbe-83c9570d9...@d34g2000vbm.googlegroups.com>,
> > Kieran Mullen <kie...@ou.edu> writes
> >
> >
> >
> > > I use science fiction in my Intro Physics class. I've used "The
> > >Cold Equations" to discuss Newton's Laws of Motion, and "Neutron Star"
> > >to discuss gravity and tidal forces. I'll use one of the "Tales of
> > >the White Hart" to discuss potential energy.
> >
> > > I can't think of any story which focuses on simple harmonic
> > >oscillation, e.g. a spring or the like. I'm looking for a story where
> > >the science or math of oscillation is important; if I just wanted
> > >references to oscillation I could go with "Foucault's Pendulum" or
> > >something :-).
> >
> > "The Men and the Mirror" by Russ Rocklynne. Pendulum motion and
> > precession in one.
> > --
> > To reply, my gmail address is nojay1 Robert Sneddon
>
> Actually, I plan to use that later in discussing angular momentum.
> The Ross Rocklynne story screws up conservation of angular momentum.
How? If the story is the one I remember, the two men drew themselves
together really close. Due to conservation of angular momentum, they were
orbiting each other really fast. Then they cut the rope connecting them, and
both had enough speed to exit the mirror.
David DeLaney
Hmm. That one Alderson Disk story where the sun's bobbing up and down in
the hole in the middle?
Oh, I know - The Men and the Mirror, by ... moment ... Ross Rocklynne.
Simple harmonic oscillation except it's also got angular momentum involved,
and the math is fairly important to the two trapped men...
Dave
--
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It's not the clock that slows the hour The definition's plain for anyone to see
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David DeLaney
>Of course *the* SF story on oscilation is the Van Vogt one that was grafted
>onto _Weapon Shops of Isher_, though the thought of teaching science using
>Van Vogt boggles..
"See this? DON'T DO THAT".
Dave "always available as a horrid example, in other words" DeLaney
Des
I think that AC Clarke's "Fountains of Paradise" had a prototype
Beanstalk on Mars which oscillated to avoid collision with the moons.
Also, might have been a story involving harmonic oscillation in one of
Colin Kapp's "Unorthodox Engineer" stories, but memory fails.
Robert Carnegie: Fnord: cc talk-origins@moderators.isc.org
Right on _The Fountains of Paradise_, although we only see the Mars
beanstalk (orbital tower, space elevator) as a computer design.
However, harmonics as a problem for a space elevator is made more of.
Also, the Tacoma Narrows bridge film is discussed in the story, so you
certainly could use that. Not the same thing is when an astronaut
falls off the top of the Tower and in due course returns to where she
fell from - but long after the limit of her air supply. No rescue
possible. So in the meantime she's phoned her goodbyes and then
opened her faceplate.
Robert Carnegie: Fnord: cc talk-origins@moderators.isc.org
> In article <haj74f$l1...@news.eternal-september.org>,
>
> lal_truckee <lal_truc...@yahoo.com> wrote:
> > It's a YASID since I can't remember much but the oscillation, but
> > there's a story about a nano black hole falling into the earth and
> > orbiting beneath the surface "vertically" i.e. oscillating. Much
> > consternation ensues until someone calculates the growth rate of
> > something so small that the atoms it falls through are as distant
> > galaxies - it won't eat the earth until long after the heat death of the
> > sun IIRC.
>
> > P.S. We can date this story either by my fallible memory of reading it
> > "a long time ago," or by noting it has to be before Hawkins informed us
> > that nano black holes would evaporate.
>
> The following is not meant to be critical in any way, but is rather
> genuine curiosity.
>
> Why do so many people misspell Hawking's name? I so frequently see
> Hawkin or Hawkins or Hawkings or similar things. It seems like a pretty
> easy English name, easier to spell than Einstein. And yet I never see
> Einstein misspelled, but it seems that any reference to Hawking is as
> likely to be spelled wrong as right.
Hawkins /is/ a common name. Hawking isn't. I think it's the same
thing with Lieber and Leiber, except that you can also crossbreed
Hawkins and Hawking to get Hawkings, and maybe that's where Hawkin
comes from too, as well as mistyping and missing the last letter.
It's rather like a Star Trek character initially being remembered by
most of the audience as Dr. Spock.
Robert Carnegie: Fnord: cc talk-origins@moderators.isc.org
Not a story but <http://en.wikipedia.org/wiki/Millennium_Bridge_
%28London%29>
Something about alien music perhaps?
<http://www.midicode.com/tunings/greek.shtml> says
"The upper left illustration depicts Jubal, the biblical father of
music, and six blacksmiths with differing size hammers striking an
anvil. This relates to the story that the young Pythagoras was first
moved to investigate musical intervals on hearing the notes produced
by different size hammers at a blacksmith's shop."
How would an SF story use the physics of harmonics? I suppose either
to send a signal to the other end of the string that will only appear
as detectable because it's correctly tuned, or else to shake something
until it breaks. Well, the famous real cases are probably good enough
for that. Maybe there's an Asimov tall tale about the singing pitch
that breaks glass, and I think the later Star Trek series talk about
the defence shield harmonics and how it's necessary to vary them to
prevent or allow either phaser rays or the Transporter to penetrate or
not. Which brings us to popular electronics and _Venus Equilateral_.
Now there's a fairly amusing story semi-attached there - it's in one
of the collections - where some young residents of the Mars colonies
find an old Marsie electronic device and repeatedly power it up to see
what it does. "Repeatedly" because mainly it trips fuses or circuit
breakers, which our heroes proceed to gimmick, and also burns
wallpaper and blows holes in the street (it's a very suburban Mars
colony). Intercut with the tale of a senior Martian electrician and
his apprentice installing the thing in the first place. I think it
turns out to be an inter-city wireless power waveguide. Students
might take home the lesson not to fool around with electric stuff, but
then again they might be inspired, and you, arrested...
How do you actually use an SF story in a class? Assign it as home
reading? I'd suppose that a story would take up a lot of teaching
time whilst only making one scientific point.
Maybe you could assign "Reduce this story to a one page precis whilst
maintaining all the relevant scientific information."
Or "Spot all the mistakes."
Jack Bohn
>The following is not meant to be critical in any way, but is rather
>genuine curiosity.
>
>Why do so many people misspell Hawking's name?
I know Penn Jillette (and it will be justice if I misspelled his
name) referred to him as "Screamin' Stephen Hawking" in a column
he used to do in the back of some computer mag. I don't know if
there are that many fans of computers, Penn & Teller, and
Screamin' Jay Hawkins, but it's a start.
--
-Jack
Butch Malahide
> Which brings us to popular electronics and _Venus Equilateral_.
> Now there's a fairly amusing story semi-attached there - it's in one
> of the collections - where some young residents of the Mars colonies
> find an old Marsie electronic device and repeatedly power it up to see
> what it does. "Repeatedly" because mainly it trips fuses or circuit
> breakers, which our heroes proceed to gimmick, and also burns
> wallpaper and blows holes in the street (it's a very suburban Mars
> colony). Intercut with the tale of a senior Martian electrician and
> his apprentice installing the thing in the first place. I think it
> turns out to be an inter-city wireless power waveguide.
"Lost Art" by George O. Smith
http://www.isfdb.org/cgi-bin/title.cgi?46749
netcat
@h30g2000vbr.googlegroups.com>, rja.ca...@excite.com says...
> On Oct 8, 5:43 am, Mike Ash <m...@mikeash.com> wrote:
> > Why do so many people misspell Hawking's name? I so frequently see
> > Hawkin or Hawkins or Hawkings or similar things. It seems like a pretty
> > easy English name, easier to spell than Einstein. And yet I never see
> > Einstein misspelled, but it seems that any reference to Hawking is as
> > likely to be spelled wrong as right.
>
> Hawkins /is/ a common name. Hawking isn't. I think it's the same
> thing with Lieber and Leiber
Tolkein isn't any commoner than Tolkien, I don't think.
rgds,
netcat
garabik-ne...@kassiopeia.juls.savba.sk
Incandescence by Greg Egan.
Though you'd better wait with the novel until you teach General relativity ;-)
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mikea
> On Oct 8, 8:58?am, Des <desmondkavan...@gmail.com> wrote:
>> On Oct 7, 10:16?pm, Kieran Mullen <kie...@ou.edu> wrote:
>>
>> > ? ?I ?use science fiction in my Intro Physics class. ? I've used "The
>> > Cold Equations" to discuss Newton's Laws of Motion, and "Neutron Star"
>> > the White Hart" to discuss potential energy.
>>
>> > oscillation, e.g. a spring or the like. ?I'm looking for a story where
>> > the science or math of oscillation is important; ?if I just wanted
>> > references to oscillation I could go with "Foucault's Pendulum" or
>> > something :-).
>>
>> > Thanks,
>>
>> > Kieran Mullen
>>
>> I think that AC Clarke's "Fountains of Paradise" had a prototype
>> Beanstalk on Mars which oscillated to avoid collision with the moons.
>> Also, might have been a story involving harmonic oscillation in one of
>> Colin Kapp's "Unorthodox Engineer" stories, but memory fails.
>
> Right on _The Fountains of Paradise_, although we only see the Mars
> beanstalk (orbital tower, space elevator) as a computer design.
> However, harmonics as a problem for a space elevator is made more of.
> Also, the Tacoma Narrows bridge film is discussed in the story, so you
> certainly could use that. Not the same thing is when an astronaut
> falls off the top of the Tower and in due course returns to where she
> fell from - but long after the limit of her air supply. No rescue
> possible. So in the meantime she's phoned her goodbyes and then
> opened her faceplate.
The Tacoma Narrows bridge failure is a good example of externally-driven
oscillation; the flutter frequency just happened to be one of the
frequencies at which the structure was (very nearly) at resonance.
A real-life horror story, in which many lives were lost, is that of the
Lockheed Electra, in which numerical analysis of the vibration modes
for the wings was done incorrectly: the partial sums of the eigenvalues
were accumulated using single precision. As a result, very small numbers
which were added added to those partial sums were effectively zero,
causing all the eigenvalues from the faulty analysis to be in the left
(real part negative or zero) half of the complex plane. Post-failure, the
program was examined, the error located and corrected, and at least one
of the eigenvalues turned out to have a real part > 0, and so (to make
a long story shorter) the wings fell off in flight. Another example of
externally-driven oscillation.
See also the results of a Google search on
'"whirl mode" aircraft OR engine OR wing'
(without the outer apostrophes).
--
Cynic, n: a blackguard whose faulty vision sees things as they are, not as they
ought to be.
- Ambrose Bierce
Butch Malahide
>
> The Tacoma Narrows bridge failure is a good example of externally-driven
> oscillation; the flutter frequency just happened to be one of the
> frequencies at which the structure was (very nearly) at resonance.
The wikipedia article (which is way too technical for me) apparently
debunks the resonance explanation of the Tacoma Narrows bridge
failure.
http://en.wikipedia.org/wiki/Tacoma_Narrows_Bridge_(1940)#Resonance_hypothesis
Lawrence Watt-Evans
wrote:
>Mike Ash wrote:
>
>>Why do so many people misspell Hawking's name?
>
>I know Penn Jillette (and it will be justice if I misspelled his
>name) referred to him as "Screamin' Stephen Hawking" in a column
>he used to do in the back of some computer mag. I don't know if
>there are that many fans of computers, Penn & Teller, and
>Screamin' Jay Hawkins, but it's a start.
Well, there's me.
--
My webpage is at http://www.watt-evans.com
I'm selling my comic collection -- see http://www.watt-evans.com/comics.html
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Robert Carnegie: Fnord: cc talk-origins@moderators.isc.org
orig...@moderators.isc.org <rja.carne...@excite.com> wrote:
> Maybe there's an Asimov tall tale about the singing pitch
> that breaks glass,
Oh! Oh! Anne McCaffrey:
<http://en.wikipedia.org/wiki/Crystal_Singer>
But with maybe too many sex scenes (depending on version and whether I
remember correctly)... what student age are we talking about?
Mike Ash
wrote:
> A real-life horror story, in which many lives were lost, is that of the
> Lockheed Electra, in which numerical analysis of the vibration modes
> for the wings was done incorrectly: the partial sums of the eigenvalues
> were accumulated using single precision. As a result, very small numbers
> which were added added to those partial sums were effectively zero,
> causing all the eigenvalues from the faulty analysis to be in the left
> (real part negative or zero) half of the complex plane. Post-failure, the
> program was examined, the error located and corrected, and at least one
> of the eigenvalues turned out to have a real part > 0, and so (to make
> a long story shorter) the wings fell off in flight. Another example of
> externally-driven oscillation.
>
> See also the results of a Google search on
> '"whirl mode" aircraft OR engine OR wing'
> (without the outer apostrophes).
For a fun illustration of this phenomenon, here's a video:
http://www.youtube.com/watch?v=kQI3AWpTWhM
Note that the glider shows there was specially reinforced for this test
flight. A normal one would have had the wings fall off before the pilot
had any chance to slow down.
Szymon Sokół
But "kein" is a common German word, so Tol-kein seems more familiar to
German speakers, I think. Why people who do not know a single German word do
the same mistake, I have no idea.
BTW, I have noticed that I often mistype "Nicoll" as "Nicholl", and I know
why: Captain Nicholl is one of the heroes of Jules Verne's "The Moon-Voyage"
<http://www.classicreader.com/book/2343/>, which was one of the favourite
books of my childhood (together with "The Mysterious Island").
--
Szymon Sokół (SS316-RIPE) -- Network Manager B
Computer Center, AGH - University of Science and Technology, Cracow, Poland O
http://home.agh.edu.pl/szymon/ PGP key id: RSA: 0x2ABE016B, DSS: 0xF9289982 F
Free speech includes the right not to listen, if not interested -- Heinlein H
mikea
Dear God! I *hope* the main spar and the attachment points were specially
reinforced. That's a pants-stainer! I wasn't able to tell much from the
audio, other than that someone's calling out numbers in German. Anyone
else?
--
Part of the MicroSloth Experience is having your Winblows machine cracked
and some zombieware planted in the middle of all that code, like a wasp's
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Reinstall.
Simon Slavin
> I can't think of any story which focuses on simple harmonic
> oscillation, e.g. a spring or the like.
William Tenn: _Brooklyn Project_, 1948
in Groff Conklin: _17 x Infinity_, 1963
If you remember the phrase "The Five Who Spiral" then you remember this
story.
There's also a story in Kapp's Unorthodox Engineers series, where a
huge collection of unstrung harps spread over a desert turned out to be
a method of generating electricity from wind.
--
I'm trying a new usenet client for Mac, Nemo OS X, since 0 days.
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Johnny Tindalos
> Why do so many people misspell Hawking's name?
Bastard tried to run me over in Cambridge in 1994.
"Death on four wheels" is an understatement...that man can MOVE...were it
not for the rapid reflexes of a really horrible (yet alert, admiring of the
works of Greg Bear, and *really* quick-thinking) girl, I would not be here
today to post about it...
Butch Malahide
> On 10-08-2009, Kieran Mullen <kie...@ou.edu> wrote:
>
> > I can't think of any story which focuses on simple harmonic
> > oscillation, e.g. a spring or the like.
>
> William Tenn: _Brooklyn Project_, 1948
> in Groff Conklin: _17 x Infinity_, 1963
And a bunch of other places:
http://www.isfdb.org/cgi-bin/title.cgi?41581
> If you remember the phrase "The Five Who Spiral" then you remember this
> story.
I remember it well. Not the first time-travel story I ever read, but
it made an impression on me in 1948, when I found it in my Uncle
Larry's (R.I.P.) copy of Planet Stories.
But I don't think you can call it simple harmonic oscillation. Rather
it is damped oscillation. Negatively damped, as the oscillations are
getting bigger. You could also call that time-reversed damped
oscillation. Well, metatime-reversed in this case.
Mike Ash
Johnny Tindalos <Jama...@UnrealEmail.arg> wrote:
Is your near death-by-wheelchair the reason you misspell his name now,
or is this just an incredibly amusing digression?
Mike Ash
wrote:
> > For a fun illustration of this phenomenon, here's a video:
> >
> > http://www.youtube.com/watch?v=kQI3AWpTWhM
> >
> > Note that the glider shows there was specially reinforced for this test
> > flight. A normal one would have had the wings fall off before the pilot
> > had any chance to slow down.
>
> Dear God! I *hope* the main spar and the attachment points were specially
> reinforced. That's a pants-stainer! I wasn't able to tell much from the
> audio, other than that someone's calling out numbers in German. Anyone
> else?
A warning before proceeding further: I'm not an aeronautical engineer,
or any other kind of "real" engineer (software doesn't count), or even
particularly knowledgeable about this stuff. I just fly the things.
More information about this flight test can be found at the bottom of
this page:
http://www.dg-flugzeugbau.de/dg1000-flattern-e.html
Two modifications were made to this plane. First, the wingspan was
increased by 2 meters, and second, the wings were filled with water
ballast in excess of the standard amount. This excess water triggered
flutter at a much lower than normal airspeed, and this is what allowed
the aircraft to survive.
Notably, it was NOT structurally reinforced, at least not beyond
whatever would have been required for the additional wingspan. (I got
that part wrong; I think I was misremembering the extra ballast.) The
deflections seen in the video really aren't that dramatic at all. You
can do the same thing to a typical glider by just grabbing a wing tip
and giving a good vigorous shake, and you can get more deflection by
going from the maximum allowed negative to positive loading. I *assume*
that the reason everything remained intact was because the flutter
occurred at an airspeed of about 150km/h, rather than the roughly
300km/h at which a glider like that would be expected to experience
flutter in a normal configuration.
Barath
Thanks for the link and the inputs. If I understand the link
correctly, the Tacoma Narrows bridge failure *is* a good example for
teaching oscillation and natural vibration modes; the objection seems
to be that it is not a good example for externally driven periodic
excitation (mechanically driven or vortex shedding driven). i.e. it
seems to be about the definition and usage of the word "resonance".
Mikea's wording would therefore be pretty accurate.
Am I reading this right ?
http://en.wikipedia.org/wiki/Aeroelasticity#Flutter
"Flutter can occur in any object within a strong fluid flow, under the
conditions that a positive feedback occurs between the structure's
natural vibration and the aerodynamic forces "
William December Starr
Johnny Tindalos <Jama...@UnrealEmail.arg> said:
> "Mike Dworetsky" <plati...@pants.btinternet.com> wrote
>
>> There's a Gregory Benford novel in the series about
>> humans/cyborgs in the far future, in which one of them falls into
>> the axial core of a planet and freefalls from surface to centre,
>> back up to the other pole, and back again. Even includes a
>> formula for the cycle period. (Same as the shortest circular
>> orbital period IIRC.) Sorry I can't recall title.
>
> That's Killeen Bishop, in _Tides of Light_.
>
> Wins the prize for Best Use of Cosmic String...
Was that segment of the novel ever published as a short story?
If not then I have a YASID for a story that's tickling my memory
about a human who violates a no-go volume, declared by very advanced
aliens, in space over the pole of a planet (Venus, after the aliens
have modified it?) and as apparent punishment is snagged and placed
at "ground level" over the hole that the aliens have created clear
through the planet, and immediately starts falling. He seems doomed
to oscillate back and forth, and therefore to die when he runs out
of oxygen, but he figures out some clever way (I forget what) to
utilize some resources of his spacesuit to get out of the trap and
survive, and then wonders whether the aliens really wanted to kill
him or were just testing his intelligence.
If it's of any help, I _may_ have read this story in one of Dozois'
_The Year's Best Science Fiction_ anthologies.
-- wds
Mike Dworetsky
news:ham9h3$p5h$1...@panix2.panix.com...
Ah--I have it. "Alphas" by Gregory Benford. A short story in the 1990
collection. Originally in Amazing Stories, c. 1989. A very similar
situation, with drawings and formula.
It's pretty obvious that the author has simply used the same basic idea (of
his own) in two works published around the same time.
--
Mike Dworetsky
(Remove pants sp*mbl*ck to reply)
Robert Carnegie: Fnord: cc talk-origins@moderators.isc.org
> In article <Xns9C9EDDA4FAB15JamaisVuUnrealEma...@216.196.109.145>,
> Johnny Tindalos <Jamai...@UnrealEmail.arg> wrote:
>
> > Mike Ash <m...@mikeash.com> wrote in
> >news:mike-E2F3E4.0...@news.eternal-september.org:
>
> > > Why do so many people misspell Hawking's name?
>
> > Bastard tried to run me over in Cambridge in 1994.
>
> > "Death on four wheels" is an understatement...that man can MOVE...were it
> > not for the rapid reflexes of a really horrible (yet alert, admiring of the
> > works of Greg Bear, and *really* quick-thinking) girl, I would not be here
> > today to post about it...
>
> Is your near death-by-wheelchair the reason you misspell his name now,
> or is this just an incredibly amusing digression?
Is "Hawkings" short for "Hawking the Slayer"?
I met a wheelchair user with serious speech impairment in a courtyard
in St John's College, Cambridge, in the mid or late 1980s, once. I
have wondered whether that was Professor Hawking. Wrong college, I
think - but they are pretty much boundary-less (well, they have big
doors and high walls, but that's to keep you in at night) - and maybe
wrong time for his progressive impairments. I think the man I met
asked me to rearrange the carrier bags of shopping that were hung
onnhis chair, or to hand one of them around to him, and was annoyed
that I didn't initially understand what he was saying. But I suppose
that could have been anybody, within the parameters given.
I was previously aware of Professor Hawking, I think, from a
description written by Larry Niven that you may have seen. But I
didn't think of it at the time. And I didn't have a sense of danger.
Embarrassment, yes.
Robert Carnegie: Fnord: cc talk-origins@moderators.isc.org
> On Oct 8, 6:24 pm, Butch Malahide <fred.gal...@gmail.com> wrote:
>
> > On Oct 8, 7:47 am, mikea <mi...@mikea.ath.cx> wrote:
>
> > > The Tacoma Narrows bridge failure is a good example of externally-driven
> > > oscillation; the flutter frequency just happened to be one of the
> > > frequencies at which the structure was (very nearly) at resonance.
>
> > The wikipedia article (which is way too technical for me) apparently
> > debunks the resonance explanation of the Tacoma Narrows bridge
> > failure.
>
> >http://en.wikipedia.org/wiki/Tacoma_Narrows_Bridge_(1940)#Resonance_h...
>
> Thanks for the link and the inputs. If I understand the link
> correctly, the Tacoma Narrows bridge failure *is* a good example for
> teaching oscillation and natural vibration modes; the objection seems
> to be that it is not a good example for externally driven periodic
> excitation (mechanically driven or vortex shedding driven). i.e. it
> seems to be about the definition and usage of the word "resonance".
> Mikea's wording would therefore be pretty accurate.
>
> Am I reading this right ?
Anyway, if the point of using sci-fi is just to establish a "sense of
wonder" about science itself, and the day's topic in physics, then
video of a bridge torn down by Natural Philosophy in action fits the
bill.
Did anyone blame the CIA for it?
Richard R. Horton
wrote:
>One possibility is a Niven story wherein a character releases a mini-
>black hole on Mars. It oscillates through Mars and comes back just in
>time to kill his rival by rather acute organ disruption. (I'm not
>posting a YASID on that one since I think I can track it down).
>However, I had already used Niven once in the course.
How about Gregory Benford's story "Alphas", which is a rejiggered
version of an episode in one of his long series about
b/e/r/s/e/r/k/e/r/s machines inimical to humanity ... GALACTIC CENTER,
was it called?
Anyway, "Alphas" the short story appeared in AMAZING STORIES, don't
know if it's been reprinted. It's about a guy oscillating through the
center of a planet that has had a cylindrical hole driven from pole to
pole.
Richard R. Horton
<Jama...@UnrealEmail.arg> wrote:
>> There's a Gregory Benford novel in the series about humans/cyborgs in
>> the far future, in which one of them falls into the axial core of a
>> planet and freefalls from surface to centre, back up to the other
>> pole, and back again. Even includes a formula for the cycle period.
>> (Same as the shortest circular orbital period IIRC.) Sorry I can't
>> recall title.
>>
>
>That's Killeen Bishop, in _Tides of Light_.
Yes ... and as I noted in another post (later than yours, I hasten to
add) Benford reworked this into a short story called "Alphas" (with a
different main character).
Anthony Nance
> Ted Nolan <tednolan> <t...@loft.tnolan.com> wrote:
>>Of course *the* SF story on oscilation is the Van Vogt one that was grafted
>>onto _Weapon Shops of Isher_, though the thought of teaching science using
>>Van Vogt boggles..
That came to mind with respect to resonance, actually.
> "See this? DON'T DO THAT".
And that quickly came to mind as well!
- Tony
> Dave "always available as a horrid example, in other words" DeLaney
David DeLaney
>I met a wheelchair user with serious speech impairment in a courtyard
>in St John's College, Cambridge, in the mid or late 1980s, once. I
>have wondered whether that was Professor Hawking.
Did he look like this?
http://en.wikipedia.org/wiki/File:Stephen_Hawking.StarChild.jpg
- for some reason, he got a high dose of "stereotypical nerd" appearance,
in my opinion.
Dave
--
\/David DeLaney posting from d...@vic.com "It's not the pot that grows the flower
It's not the clock that slows the hour The definition's plain for anyone to see
Love is all it takes to make a family" - R&P. VISUALIZE HAPPYNET VRbeable<BLINK>
http://www.vic.com/~dbd/ - net.legends FAQ & Magic / I WUV you in all CAPS! --K.
Mark Zenier
Des <desmond...@gmail.com> wrote:
>On Oct 7, 10:16�pm, Kieran Mullen <kie...@ou.edu> wrote:
>> � �I �use science fiction in my Intro Physics class. � I've used "The
>> Cold Equations" to discuss Newton's Laws of Motion, and "Neutron Star"
>> the White Hart" to discuss potential energy.
>>
>> oscillation, e.g. a spring or the like. �I'm looking for a story where
>> the science or math of oscillation is important; �if I just wanted
>> references to oscillation I could go with "Foucault's Pendulum" or
>> something :-).
>>
>> Thanks,
>>
>> Kieran Mullen
>
>I think that AC Clarke's "Fountains of Paradise" had a prototype
>Beanstalk on Mars which oscillated to avoid collision with the moons.
>Also, might have been a story involving harmonic oscillation in one of
>Colin Kapp's "Unorthodox Engineer" stories, but memory fails.
The power system in "The Subways of Tazoo", perhaps.
Mark Zenier mze...@eskimo.com
Googleproofaddress(account:mzenier provider:eskimo domain:com)
Mike Ash
d...@gatekeeper.vic.com (David DeLaney) wrote:
> Robert Carnegie: <rja.ca...@excite.com> wrote:
> >I met a wheelchair user with serious speech impairment in a courtyard
> >in St John's College, Cambridge, in the mid or late 1980s, once. I
> >have wondered whether that was Professor Hawking.
>
> Did he look like this?
> http://en.wikipedia.org/wiki/File:Stephen_Hawking.StarChild.jpg
>
> - for some reason, he got a high dose of "stereotypical nerd" appearance,
> in my opinion.
The huge glasses, clothes in disarray, and crazy grin certainly do give
that impression. The difference being, of course, that he probably
couldn't really control 2/3rds of those.
Robert Carnegie
> Robert Carnegie: <rja.ca...@excite.com> wrote:
> >I met a wheelchair user with serious speech impairment in a courtyard
> >in St John's College, Cambridge, in the mid or late 1980s, once. I
> >have wondered whether that was Professor Hawking.
>
> Did he look like this?
> http://en.wikipedia.org/wiki/File:Stephen_Hawking.StarChild.jpg
I'm sorry, I don't remember. Anyway, I've seen him on TV. On Star
Trek.
> - for some reason, he got a high dose of "stereotypical nerd" appearance,
> in my opinion.
The least of his problems. But apparently he very pragmatically set
out to be a Famous Physicist in order to make money enough to support
his family if his career and/or life were cut short. He may have
played up the appearance.
More pictures at
<http://www.telegraph.co.uk/news/picturegalleries/uknews/5189606/
Professor-Stephen-Hawking-in-pictures.html?image=1>
..which is panel No.2 in a set, control on right of page.
Wedding picture (first) with walking stick. Not usually a young man's
accessory.
Johnny Tindalos
> In article <Xns9C9EDDA4FAB15Ja...@216.196.109.145>,
> Johnny Tindalos <Jama...@UnrealEmail.arg> wrote:
>
>> Mike Ash <mi...@mikeash.com> wrote in
>> news:mike-E2F3E4.0...@news.eternal-september.org:
>>
>> > Why do so many people misspell Hawking's name?
>>
>> Bastard tried to run me over in Cambridge in 1994.
>>
>> "Death on four wheels" is an understatement...that man can
>> MOVE...were it not for the rapid reflexes of a really horrible (yet
>> alert, admiring of the works of Greg Bear, and *really*
>> quick-thinking) girl, I would not be here today to post about it...
>
> Is your near death-by-wheelchair the reason you misspell his name now,
> or is this just an incredibly amusing digression?
>
It gave me a certain...slant on the man, shall we say (I'd read his book,
dammit! I looked up to him! And then I actually see him in the flesh, and
he tries to take my life!); for this reason when I first encountered a
text-to-speech program[*] a few months afterwards, I amused myself (in a
rather juvenile fashion of which I would like to able to say I am now
ashamed) by learning to make it sound just like him; however it was
freeware and had _extremely_ simple phoneme recognition, so in order to
make it say "Fly, you fools! For I am Stephen Hawking!" one had to type
something like "Fffliii yuuu phouulss, fauur Eyeh ammm Steeevuunn
Horrrkkinng".....so "Steevun Horking" he became and has remained since,
deep in my secret, childish, and vindictively amused soul.
[*] We'd acquired it for one of my brother's art projects, about the
great artists and their peccadillos. It was my job to make it work, which
involved teaching it how to say things like TOULOUSE-LAUTREC: BROTHEL-
CRAWLING SEX DWARF
...and now he's been security-cleared to meet the Queen; if only they
knew...
...ah well, it's Art, neh?
Johnny Tindalos
news:uq7uc513buvpo8kvn...@4ax.com:
Oh, I see; never came across that one!
tkma...@yahoo.co.uk
> I use science fiction in my Intro Physics class. I've used "The
> Cold Equations" to discuss Newton's Laws of Motion, and "Neutron Star"
> to discuss gravity and tidal forces. I'll use one of the "Tales of
> the White Hart" to discuss potential energy.
>
> I can't think of any story which focuses on simple harmonic
> oscillation, e.g. a spring or the like. I'm looking for a story where
> the science or math of oscillation is important; if I just wanted
> references to oscillation I could go with "Foucault's Pendulum" or
> something :-).
A E van Vogt - "Seesaw": A man is sent on a time see-saw. In one of the
Isaac Asimov Presents Great SF Stories books.
John Campbell - "Forgetfulness": Time oscillations appear in the story,
though it's primarily about "civilizations tend to forget primitive
technology from their humbler past". In _Adventures in Time & Space_ (I
think).
--
"McNear had responded to the inexplicable as people often do: he had
ignored its existance. An excellent way to maintain sanity."
- "Practice" by Verge Foray
<http://variety-sf.blogspot.com/2009/10/howard-l-myers-practice-as-by-verge.html>
tkma...@yahoo.co.uk
> William Tenn: _Brooklyn Project_, 1948
Online here (need to scroll down):
<http://web.pitas.com/kerfluffleb/jul2aug2003.html>
Quadibloc
> I use science fiction in my Intro Physics class. I've used "The
> Cold Equations" to discuss Newton's Laws of Motion, and "Neutron Star"
> to discuss gravity and tidal forces. I'll use one of the "Tales of
> the White Hart" to discuss potential energy.
>
> I can't think of any story which focuses on simple harmonic
> oscillation, e.g. a spring or the like. I'm looking for a story where
> the science or math of oscillation is important; if I just wanted
> references to oscillation I could go with "Foucault's Pendulum" or
> something :-).
I remembered one where a metal sphere was sent back in time, and it
oscillated back and forth between past and future - each time it went
to the past, it made changes, but the scientists doing the experiment
were unaware, because they belonged to whichever new timeline had been
created.
This one, I see, was mentioned in this thread: "The Brooklyn Project"
by William Tenn. More illustrative of chaos theory than simple
harmonic motion, really, but...
John Savard