Science > Physics > Q. about max acceleration, Planck's constant, PLUS: help locate SciAm column (Amtr. Sci)
| Topic: |
Science > Physics |
| User: |
"" |
| Date: |
13 Jan 2008 01:49:58 AM |
| Object: |
Q. about max acceleration, Planck's constant, PLUS: help locate SciAm column (Amtr. Sci) |
I read something indicating there is a maximum acceleration that
anything physically can take: a maximum G-force. I don't mean how
large objects will fall apart, I mean a max. G that even, say, a
single PROTON or NEUTRON will take. I think the author indicated that
exceeding this max will not cause a proton, say, to fall apart, but
just that the extra energy will be wasted and have no additional
accelerating effect. Apparently this has something to do with Planck's
Constant. Could someone tell us about this?
I understand the most rudimentary basics of Planck's Constant [and of
physics in general] ( constant = 6.26 joule-secs?), hv, etc. : it has
to do with the quanta: the discreet packets that energy consists of.
But I really don't remember what the author said and I cannot re-
locate the article.
That's my main question. But also: where I read this was a really
"cute" edition of the Amateur Scientist column in Scientific American.
A tongue in cheek essay, this was, and it was probably in a decades
old issue of Sci Am. I have researched this online and in university
library stacks and CANNOT find the Sci Am issue that had this column!
I emailed Sci Am about it and THEY couldn't help me locate it!
The column expressed the heartfelt desire of many of us for greater
advances in space exploration and related technology. With aplomb and
a "straight face," the author told the amateur how to build an
electromagnetic accelator capable of pushing heavy projectiles to near
light speed and send them off to other stars! He even listed specific
parts to buy from Radio Shack! The quantities involved would be kind
of budget-stretching, however! :-) It is in this article that the
constraints on maximum G-forces and Planck's Constant were mentioned.
Can anybody locate which issue of Scientific American this Amateur
Scientist column was in? It could have been from anywhere in the
nineties back to the sixties.
.
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|
| User: "Androcles" |
|
| Title: Re: Q. about max acceleration, Planck's constant, PLUS: help locate Sci Am column (Amtr. Sci) |
13 Jan 2008 04:34:17 AM |
|
|
<giveitawhril2008@gmail.com> wrote in message
news:701f1956-35ed-400b-8e43-77292f134258@k39g2000hsf.googlegroups.com...
|I read something indicating there is a maximum acceleration that
| anything physically can take: a maximum G-force. I don't mean how
| large objects will fall apart, I mean a max. G that even, say, a
| single PROTON or NEUTRON will take. I think the author indicated that
| exceeding this max will not cause a proton, say, to fall apart, but
| just that the extra energy will be wasted and have no additional
| accelerating effect. Apparently this has something to do with Planck's
| Constant. Could someone tell us about this?
|
| I understand the most rudimentary basics of Planck's Constant [and of
| physics in general] ( constant = 6.26 joule-secs?), hv, etc. : it has
| to do with the quanta: the discreet packets that energy consists of.
| But I really don't remember what the author said and I cannot re-
| locate the article.
First of all you are confusing acceleration with force, a common
mistake. I feel a force on my butt while sitting in my chair, but I
am not accelerating. The chair is pushing me up with the same
force gravity is pulling me down.
Acceleration is a change in velocity, so when I drop an object
from a tall tower it accelerates earthwards until it hits the ground,
and then its velocity changes once again. That's when it breaks.
Atom smashers do much the same thing.
http://hands-on-cern.physto.se/ani/acc_lhc_atlas/lhc_atlas.swf
This video may help:
http://www.youtube.com/watch?v=VKCdq6X08Sw
| That's my main question. But also: where I read this was a really
| "cute" edition of the Amateur Scientist column in Scientific American.
| A tongue in cheek essay, this was, and it was probably in a decades
| old issue of Sci Am. I have researched this online and in university
| library stacks and CANNOT find the Sci Am issue that had this column!
| I emailed Sci Am about it and THEY couldn't help me locate it!
|
| The column expressed the heartfelt desire of many of us for greater
| advances in space exploration and related technology. With aplomb and
| a "straight face," the author told the amateur how to build an
| electromagnetic accelator capable of pushing heavy projectiles to near
| light speed and send them off to other stars! He even listed specific
| parts to buy from Radio Shack! The quantities involved would be kind
| of budget-stretching, however! :-) It is in this article that the
| constraints on maximum G-forces and Planck's Constant were mentioned.
|
| Can anybody locate which issue of Scientific American this Amateur
| Scientist column was in? It could have been from anywhere in the
| nineties back to the sixties.
Yeah, well, when Google gets around to scanning every publication
ever written you may find a slight information overload with as much
contradiction as there is information.
.
|
|
|
|
| User: "" |
|
| Title: Re: Q. about max acceleration, Planck's constant, PLUS: help locateSci Am column (Amtr. Sci) |
13 Jan 2008 09:05:53 AM |
|
|
On 13 jan, 02:49, wrote:
I read something indicating there is a maximum acceleration that
anything physically can take: a maximum G-force. I don't mean how
large objects will fall apart, I mean a max. G that even, say, a
single PROTON or NEUTRON will take. I think the author indicated that
exceeding this max will not cause a proton, say, to fall apart, but
just that the extra energy will be wasted and have no additional
accelerating effect. Apparently this has something to do with Planck's
Constant. Could someone tell us about this?
He probably was referring to the fact that since mass exponentially
increases with velocity, more and more energy is required as the
velocity increases to increase the velocity of the increasing mass.
At some point, when near light speed is achieved, any amount of
added energy will not cause the particle to increase velocity more
than minutely, if at all when very close to the limit, which is the
speed of light.
That's the actual limit. All experiments confirm that massive
particles cannot reach the speed of light because of this.
Andr=E9 Michaud
I understand the most rudimentary basics of Planck's Constant [and of
physics in general] ( constant =3D 6.26 joule-secs?), hv, etc. : it has
to do with the quanta: the discreet packets that energy consists of.
But I really don't remember what the author said and I cannot re-
locate the article.
That's my main question. But also: where I read this was a really
"cute" edition of the Amateur Scientist column in Scientific American.
A tongue in cheek essay, this was, and it was probably in a decades
old issue of Sci Am. I have researched this online and in university
library stacks and CANNOT find the Sci Am issue that had this column!
I emailed Sci Am about it and THEY couldn't help me locate it!
The column expressed the heartfelt desire of many of us for greater
advances in space exploration and related technology. With aplomb and
a "straight face," the author told the amateur how to build an
electromagnetic accelator capable of pushing heavy projectiles to near
light speed and send them off to other stars! He even listed specific
parts to buy from Radio Shack! The quantities involved would be kind
of budget-stretching, however! :-) It is in this article that the
constraints on maximum G-forces and Planck's Constant were mentioned.
Can anybody locate which issue of Scientific American this Amateur
Scientist column was in? It could have been from anywhere in the
nineties back to the sixties.
.
|
|
|
| User: "" |
|
| Title: Re: Q. about max acceleration, Planck's constant, PLUS: help locateSci Am column (Amtr. Sci) |
13 Jan 2008 04:51:07 PM |
|
|
On Jan 13, 7:05=A0am, wrote:
On 13 jan, 02:49, wrote:
I read something indicating there is a maximum acceleration that
anything physically can take: a maximum G-force. I don't mean how
large objects will fall apart, I mean a max. G that even, say, a
single PROTON or NEUTRON will take. I think the author indicated that
exceeding this max will not cause a proton, say, to fall apart, but
just that the extra energy will be wasted and have no additional
accelerating effect. Apparently this has something to do with Planck's
Constant. Could someone tell us about this?
He probably was referring to the fact that since mass exponentially
increases with velocity, more and more energy is required as the
velocity increases to increase the velocity of the increasing mass.
At some point, when near light speed is achieved, any amount of
added energy will not cause the particle to increase velocity more
than minutely, if at all when very close to the limit, which is the
speed of light.
That's the actual limit. All experiments confirm that massive
particles cannot reach the speed of light because of this.
Andr=E9 Michaud
I understand that relativistic effects become significant at high
enough percentages of the speed of light. One of these effects is the
increase of mass. But I think the author seemed to indicate that even
starting at a standstill or low speed, one can only get a maximum
acceleration. Unless extremely high G-forces inherently generate
relativistic effects themselves, which may be true for all I know, the
author was referring to something NON-relativistic. I even vaguely
think he might have said something to the effect that radiation,
beyond a certain intensity, gets reradiated back OUT of the object,
instead of getting absorbed. Or, I may be thinking of something I
learned about thermodynamics some time back, which may NOT be what the
author was taking about, here.
.
|
|
|
| User: "Androcles" |
|
| Title: Re: Q. about max acceleration, Planck's constant, PLUS: help locate Sci Am column (Amtr. Sci) |
14 Jan 2008 12:11:18 AM |
|
|
<giveitawhril2008@gmail.com> wrote in message
news:468782cb-f357-4543-a45d-5977f7ca5469@v4g2000hsf.googlegroups.com...
On Jan 13, 7:05 am, wrote:
On 13 jan, 02:49, wrote:
I read something indicating there is a maximum acceleration that
anything physically can take: a maximum G-force. I don't mean how
large objects will fall apart, I mean a max. G that even, say, a
single PROTON or NEUTRON will take. I think the author indicated that
exceeding this max will not cause a proton, say, to fall apart, but
just that the extra energy will be wasted and have no additional
accelerating effect. Apparently this has something to do with Planck's
Constant. Could someone tell us about this?
He probably was referring to the fact that since mass exponentially
increases with velocity, more and more energy is required as the
velocity increases to increase the velocity of the increasing mass.
At some point, when near light speed is achieved, any amount of
added energy will not cause the particle to increase velocity more
than minutely, if at all when very close to the limit, which is the
speed of light.
That's the actual limit. All experiments confirm that massive
particles cannot reach the speed of light because of this.
André Michaud
| I understand that relativistic effects become significant at high
| enough percentages of the speed of light.
No, you don't understand it at all, you are just parroting some rumour
you've heard. If you understood it you wouldn't be asking silly questions.
.
|
|
|
| User: "" |
|
| Title: Re: Q. about max acceleration, Planck's constant, PLUS: help locateSci Am column (Amtr. Sci) |
14 Jan 2008 08:01:31 PM |
|
|
Andre wrote:
"in current day high energy accelerators, relativistic velocities are
reached within nanoseconds starting from rest. "
That COULD BE what the guy was talking about after all. On the other
hand, Randy noted their IS a Planck Acceleration, and gave a link, and
maybe that's what Hanson was talking about in his equations. My gut
reaction to a Planck value is it must be a minimun increment, but
looking at Hanson's equations, following Randy's link, and then doing
some Google searches, leads to: there is talk of a MAXIMUM
ACCELERATION, especially in conjunction with a guy named Caianiello.
Seems to be a cosmological concept and not tested. I'd like to see
this translated, real specifically into Gs! Also, does this
cosmological, theoretical limit apply to my Radio Shack linear
accelator? :-)
Androcles wrote:
"No, you don't understand it at all, you are just parroting some
rumour you've heard. If you understood it you wouldn't be asking silly
questions."
Ah, but they always say that there is no such thing as a silly
question! The only silly question is, why do I keep having these
dreams about you and I walking around naked at LAX? And worse, it
seems we're always about to board an Aeroflot flight to the Baikonur
Cosmodrome! These dreams must STOP!
.
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|
|
| User: "Androcles" |
|
| Title: Re: Q. about max acceleration, Planck's constant, PLUS: help locate Sci Am column (Amtr. Sci) |
14 Jan 2008 08:44:16 PM |
|
|
<giveitawhril2008@gmail.com> wrote in message
news:fde6807c-1b90-4721-b9da-7e4931824dae@k39g2000hsf.googlegroups.com...
| Andre wrote:
|
| "in current day high energy accelerators, relativistic velocities are
| reached within nanoseconds starting from rest. "
|
| That COULD BE what the guy was talking about after all. On the other
| hand, Randy noted their IS a Planck Acceleration, and gave a link, and
| maybe that's what Hanson was talking about in his equations. My gut
| reaction to a Planck value is it must be a minimun increment, but
| looking at Hanson's equations, following Randy's link, and then doing
| some Google searches, leads to: there is talk of a MAXIMUM
| ACCELERATION, especially in conjunction with a guy named Caianiello.
| Seems to be a cosmological concept and not tested. I'd like to see
| this translated, real specifically into Gs! Also, does this
| cosmological, theoretical limit apply to my Radio Shack linear
| accelator? :-)
|
| Androcles wrote:
|
| "No, you don't understand it at all, you are just parroting some
| rumour you've heard. If you understood it you wouldn't be asking silly
| questions."
|
| Ah, but they always say that there is no such thing as a silly
| question!
How's this for a silly question: Who are "they"?
| The only silly question is, why do I keep having these
| dreams about you and I walking around naked at LAX? And worse, it
| seems we're always about to board an Aeroflot flight to the Baikonur
| Cosmodrome! These dreams must STOP!
That would be another silly question.
Questions are silly when they concern the things you imagine but are
not real, such as "relativistic" - or walking around LAX naked.
.
|
|
|
|
| User: "" |
|
| Title: Re: Q. about max acceleration, Planck's constant, PLUS: help locateSci Am column (Amtr. Sci) |
14 Jan 2008 09:40:46 PM |
|
|
On 14 jan, 21:01, wrote:
Andre wrote:
"in current day high energy accelerators, relativistic velocities are
reached within nanoseconds starting from rest. "
That COULD BE what the guy was talking about after all. On the other
hand, Randy noted their IS a Planck Acceleration, and gave a link, and
maybe that's what Hanson was talking about in his equations. My gut
reaction to a Planck value is it must be a minimun increment, but
looking at Hanson's equations, following Randy's link, and then doing
some Google searches, leads to: there is talk of a MAXIMUM
ACCELERATION, especially in conjunction with a guy named Caianiello.
Seems to be a cosmological concept and not tested.
Totally hypothetical and not tested, yes.
All of those Planck limits are highly theoretical and seem to only
be mathematical limit theorizing.
I recall having discussed some of the stuff years ago, and it
became obvious that some of those Planck quantities simply
make no physical sense.
I could try to trace that stuff back if you are interested and
post the arguments.
I'd like to see
this translated, real specifically into Gs! Also, does this
cosmological, theoretical limit apply to my Radio Shack linear
accelator? :-)
You mean the 9.95$ unit ? ;-)
Quite possibly!
Andr=E9 Michaud
Androcles wrote:
"No, you don't understand it at all, you are just parroting some
rumour you've heard. If you understood it you wouldn't be asking silly
questions."
Ah, but they always say that there is no such thing as a silly
question! The only silly question is, why do I keep having these
dreams about you and I walking around naked at LAX? And worse, it
seems we're always about to board an Aeroflot flight to the Baikonur
Cosmodrome! These dreams must STOP!
.
|
|
|
|
|
|
| User: "" |
|
| Title: Re: Q. about max acceleration, Planck's constant, PLUS: help locateSci Am column (Amtr. Sci) |
13 Jan 2008 07:12:50 PM |
|
|
On 13 jan, 17:51, wrote:
On Jan 13, 7:05 am, wrote:
On 13 jan, 02:49, wrote:
I read something indicating there is a maximum acceleration that
anything physically can take: a maximum G-force. I don't mean how
large objects will fall apart, I mean a max. G that even, say, a
single PROTON or NEUTRON will take. I think the author indicated that
exceeding this max will not cause a proton, say, to fall apart, but
just that the extra energy will be wasted and have no additional
accelerating effect. Apparently this has something to do with Planck's=
Constant. Could someone tell us about this?
He probably was referring to the fact that since mass exponentially
increases with velocity, more and more energy is required as the
velocity increases to increase the velocity of the increasing mass.
At some point, when near light speed is achieved, any amount of
added energy will not cause the particle to increase velocity more
than minutely, if at all when very close to the limit, which is the
speed of light.
That's the actual limit. All experiments confirm that massive
particles cannot reach the speed of light because of this.
Andr=E9 Michaud
I understand that relativistic effects become significant at high
enough percentages of the speed of light. One of these effects is the
increase of mass. But I think the author seemed to indicate that even
starting at a standstill or low speed, one can only get a maximum
acceleration. Unless extremely high G-forces inherently generate
relativistic effects themselves, which may be true for all I know, the
author was referring to something NON-relativistic.
I doubt that such extreme acceleration as he would have been
talking about would be non-relativistic in any way shape or form,
for the simple reason that for protons, for example, in current
day high energy accelerators, relativistic velocities are reached
within nanoseconds starting from rest.
More powerful accelerators are being readied for yet more
extreme accelerations from rest. To my knowledge, the limit
is technical in nature, not a physical limitation.
If there is such a limit, I never heard about it.
I even vaguely
think he might have said something to the effect that radiation,
beyond a certain intensity, gets reradiated back OUT of the object,
instead of getting absorbed.
That would be more beyond certain frequencies, intensity doesn't
seem to be a factor. Beyond certain frequencies, radiation is
very penetrating, but there is a limit. Starting with photons of
energy 1.022 MeV, they massively convert to pairs of electron-
positron as they enter just about any material which in turn
generates all kinds of secondary radiation, which if lower than
1.022 MeV will again be very penetrating.
Below certain frequencies, the radiation is mostly radiated back
out of surfaces, as you say.
Andr=E9 Michaud
Or, I may be thinking of something I learned about thermodynamics
some time back, which may NOT be what the author was taking
about, here.
.
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| User: "Randy Poe" |
|
| Title: Re: Q. about max acceleration, Planck's constant, PLUS: help locateSci Am column (Amtr. Sci) |
13 Jan 2008 09:01:13 PM |
|
|
On Jan 13, 2:49 am, wrote:
I read something indicating there is a maximum acceleration that
anything physically can take: a maximum G-force. I don't mean how
large objects will fall apart, I mean a max. G that even, say, a
single PROTON or NEUTRON will take. I think the author indicated that
exceeding this max will not cause a proton, say, to fall apart, but
just that the extra energy will be wasted and have no additional
accelerating effect. Apparently this has something to do with Planck's
Constant. Could someone tell us about this?
There is something called "Planck units", a number of
quantities based on h which some people feel constitute fundamental
limits. For instance, the Planck length ( on the order of 10^-35 m)
might
constitute some fundamentally smallest distance in some sense.
http://en.wikipedia.org/wiki/Planck_units
And there is indeed a Planck acceleration. See here for instance:
http://www.meer.net/~planck/technical1.htm
As to what that acceleration means, who knows? All the Planck
units are, are things that can be derived from the basic
physical constants hbar, G, c and k (Boltzmann's constant).
- Randy
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|
| User: "John C. Polasek" |
|
| Title: Re: Q. about max acceleration, Planck's constant, PLUS: help locate Sci Am column (Amtr. Sci) |
15 Jan 2008 08:43:06 AM |
|
|
On Sat, 12 Jan 2008 23:49:58 -0800 (PST),
wrote:
I read something indicating there is a maximum acceleration that
anything physically can take: a maximum G-force. I don't mean how
large objects will fall apart, I mean a max. G that even, say, a
single PROTON or NEUTRON will take. I think the author indicated that
exceeding this max will not cause a proton, say, to fall apart, but
just that the extra energy will be wasted and have no additional
accelerating effect. Apparently this has something to do with Planck's
Constant. Could someone tell us about this?
I understand the most rudimentary basics of Planck's Constant [and of
physics in general] ( constant = 6.26 joule-secs?), hv, etc. : it has
to do with the quanta: the discreet packets that energy consists of.
But I really don't remember what the author said and I cannot re-
locate the article.
That's my main question. But also: where I read this was a really
"cute" edition of the Amateur Scientist column in Scientific American.
A tongue in cheek essay, this was, and it was probably in a decades
old issue of Sci Am. I have researched this online and in university
library stacks and CANNOT find the Sci Am issue that had this column!
I emailed Sci Am about it and THEY couldn't help me locate it!
The column expressed the heartfelt desire of many of us for greater
advances in space exploration and related technology. With aplomb and
a "straight face," the author told the amateur how to build an
electromagnetic accelator capable of pushing heavy projectiles to near
light speed and send them off to other stars! He even listed specific
parts to buy from Radio Shack! The quantities involved would be kind
of budget-stretching, however! :-) It is in this article that the
constraints on maximum G-forces and Planck's Constant were mentioned.
Can anybody locate which issue of Scientific American this Amateur
Scientist column was in? It could have been from anywhere in the
nineties back to the sixties.
You can form a maximum force with c^4/G = 1.21e44newton.
Applied to an electron, acceleration would be 1.328e74m/ss.
Is that any help?
John Polasek
.
|
|
|
| User: "" |
|
| Title: Re: Q. about max acceleration, Planck's constant, PLUS: help locateSci Am column (Amtr. Sci) |
15 Jan 2008 10:00:17 PM |
|
|
Andre wrote:
"I recall having discussed some of the stuff years ago, and it became
obvious that some of those Planck quantities simply make no physical
sense.....I could try to trace that stuff back if you are interested
and post the arguments. "
THAT would be interesting! Even I didn't understand half of it, some
other readers would!
John Polaseck wrote:
"You can form a maximum force with c^4/G = 1.21e44newton. Applied to
an electron, acceleration would be 1.328e74m/ss. Is that any help? "
Am I reading that right? E means times 10 the power of? 1.328 times 10
to the 74, meters per second-squared? 1 followed by 74 zeroes, wherein
a google is 1 followed by 100 zeroes!? Now that's hauling butt! Of
course, since it gets you way beyond light speed right off the bat, I
guess that would translate mostly into mass, not speed?
.
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|
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| User: "" |
|
| Title: Re: Q. about max acceleration, Planck's constant, PLUS: help locateSci Am column (Amtr. Sci) |
15 Jan 2008 10:27:55 PM |
|
|
A BIG PS, or BS:
In reading over this, I cannot believe how many times I wrote
"accelator" instead of "accelerator!" But, hey...."accelator" is
better 'cuz it has fewer syllables! Maybe I'm going to help English
become competitive with German! In fact, someone ought to do a
comparison of the efficiency of speaking in German compared to the
efficiency of speaking in Hebrew! Then we can determine which is the
true Master Race!
Oops! I jumped several tracks at Grand Central Station and got onto a
completely different subject! Sorry, pretend I didn't say that. As you
were!
:-)
.
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| User: "hanson" |
|
| Title: Re: Q. about max acceleration, Planck's constant, PLUS: help locate Sci Am column (Amtr. Sci) |
13 Jan 2008 01:51:49 PM |
|
|
ok "giveitawhril2008" here is such a whirl,
acceleration = [L]/[T^2]
Planck domain unit for [L] = L_pl = sqrt (hbar*G/c^3)
Planck domain unit for [T] = T_pl = sqrt (hbar*G/c^5)
ergo
Planck domain unit for acceleration [L]/[T^2], hence:
L_pl/T_pl^2 = sqrt (c^7/hbar*G) = ~5E102 m/s2
Mind you that all these "discussions" in/about these far fields
are mental masturbations, unless any of these equations
does produce or leads to the manufacture of some gizmo.
But enjoy the jerk off.... and thanks foe the laughs...
ahahaha... ahahahahnson
<
<giveitawhril2008@gmail.com> wrote in message
news:701f1956-35ed-400b-8e43-77292f134258@k39g2000hsf.googlegroups.com...
I read something indicating there is a maximum acceleration that
anything physically can take: a maximum G-force. I don't mean how
large objects will fall apart, I mean a max. G that even, say, a
single PROTON or NEUTRON will take. I think the author indicated that
exceeding this max will not cause a proton, say, to fall apart, but
just that the extra energy will be wasted and have no additional
accelerating effect. Apparently this has something to do with Planck's
Constant. Could someone tell us about this?
I understand the most rudimentary basics of Planck's Constant [and of
physics in general] ( constant = 6.26 joule-secs?), hv, etc. : it has
to do with the quanta: the discreet packets that energy consists of.
But I really don't remember what the author said and I cannot re-
locate the article.
That's my main question. But also: where I read this was a really
"cute" edition of the Amateur Scientist column in Scientific American.
A tongue in cheek essay, this was, and it was probably in a decades
old issue of Sci Am. I have researched this online and in university
library stacks and CANNOT find the Sci Am issue that had this column!
I emailed Sci Am about it and THEY couldn't help me locate it!
The column expressed the heartfelt desire of many of us for greater
advances in space exploration and related technology. With aplomb and
a "straight face," the author told the amateur how to build an
electromagnetic accelator capable of pushing heavy projectiles to near
light speed and send them off to other stars! He even listed specific
parts to buy from Radio Shack! The quantities involved would be kind
of budget-stretching, however! :-) It is in this article that the
constraints on maximum G-forces and Planck's Constant were mentioned.
Can anybody locate which issue of Scientific American this Amateur
Scientist column was in? It could have been from anywhere in the
nineties back to the sixties.
.
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