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Subject: Re: ABOLISH ACADEMIC TENURE -- From: Dettol
Subject: Re: Missing Plutonium -- From: Gregory Greenman
Subject: Re: Vietmath War: If US had been parliamentary, no Vietnam war? -- From: Alison Brooks
Subject: Re: This is impossible -- From: drake.79@osu.edu (Macarthur Drake)
Subject: ** structure of reality ** article 1 -revised -- From: gary.forbat@hlos.com.au (Gary Forbat)
Subject: ** structure of reality ** article 3 -- From: gary.forbat@hlos.com.au (Gary Forbat)
Subject: Re: Viper/Porsche: time, speed, distance -- From: Jack Mott
Subject: Elastic collisions -- From: Duane Morin
Subject: Tenure? On the whole, yes. Was: ABOLISH ACADEMIC TENURE -- From: "Arthur E. Sowers"
Subject: Re: "Draw" an electron, you may win fabulous prizes. -- From: ale2@psu.edu (ale2)
Subject: Vietmath War; The Killing Fields -- From: Archimedes.Plutonium@dartmouth.edu (Archimedes Plutonium)
Subject: Re: ABOLISH ACADEMIC TENURE -- From: Post.To.NewsGroup.NOT@email.thanks (Troy Shinbrot)
Subject: Re: PHYSICS RELATED JOBS -- From: ale2@psu.edu (ale2)
Subject: Re: Mach's Paradox? -- From: 74553.2603@compuserve.com (Michael Ramsey)
Subject: Re: This is impossible -- From: rdadams@access4.digex.net (Dick Adams)
Subject: Info on bacteriorhodopsin -- From: "Melvin M. Moriwaki"
Subject: Re: This is impossible -- From: Bill Wines
Subject: Re: Dif. between Math and Phys. -- From: 74553.2603@compuserve.com (Michael Ramsey)
Subject: Re: FTL Comm -- From: Sylvia Else
Subject: Re: "Draw" an electron, you may win fabulous prizes. -- From: ale2@psu.edu (ale2)
Subject: Re: This is impossible -- From: Bill Wines
Subject: measuring LASER power -- From: radman@teleport.com (r_guy)
Subject: Re: I need help right away... -- From: jxw654@anu.edu.au (J Wu)
Subject: Re: ABOLISH ACADEMIC TENURE -- From: Dettol
Subject: Tonality/Emotiveness -- From: Mark Hardie
Subject: Re: ABOLISH ACADEMIC TENURE -- From: Dettol
Subject: Re: The "force" of gravity? Please explain. -- From: kfischer@iglou.com (Ken Fischer)
Subject: Re: Does Apple (Apple) = Apple? -- From: Rebecca Harris
Subject: Re: Tired light? -- From: "Peter Diehr"
Subject: g=8pi*t...what is it? -- From: archie t.
Subject: Re: This is impossible -- From: drake.79@osu.edu (Macarthur Drake)
Subject: Re: This is impossible -- From: drake.79@osu.edu (Macarthur Drake)
Subject: Re: slingshot effect -- From: "John DeHaven"
Subject: Re: This is impossible -- From: R Mentock
Subject: Re: This is impossible -- From: R Mentock
Subject: Re: Mars Rock Crock! -- From: Barry Adams
Subject: Re: New Bad Astronomy Addition (1/7/97) -- From: mmd@zuaxp0.star.ucl.ac.uk (Michael Dworetsky)
Subject: Re: Utter Futility of Arguing With Creationites -- From: bloore@h-plus-a.com (mARCO bLOORE)
Subject: Re: Science Versus Ethical Truth. -- From: Tani Akio Hosokawa
Subject: Re: how do gyroscopes work?? -- From: jac@ibms46.scri.fsu.edu (Jim Carr)

Articles

Subject: Re: ABOLISH ACADEMIC TENURE
From: Dettol
Date: Tue, 21 Jan 1997 20:53:35 -1000
Bill Bone wrote:

> >
> snipped-
> Well stated arguments. I agree in general. Tenure is bought not earned.
> Those who get $$ for the University get tenure, irrespective of their
> 1)quality of research, 2)quality of teaching.
> Of the 3 things used to evaluate faculty for tenure, $$ is most important,
> followed distantly by quality of research/publications and lastly teaching
> ability. 
I don't think "quality" enters the equation except that I guess certain
journals are deemed to be of higher standard than others.  Generally
though its quantity that impresses.  I guess it is pretty impressive to
rack up a couple fo hundred publication while working less than twenty
hours a week. 
Perhaps I'm stirring the pot too much with the last example, which is
one I've witnessed, because it is an extreme example of the total lack
of accountability which is widespread.

> 
> P.S.
> And yes, Ive been a member of the ACS for a long time and I always ask
> myself each year when I pay the dues, "Why am I wasting my money", where
> has the ACS been to support and improve the lot of chemists around the
> world?
> 
You do get reduced rate for conferences but I guess if you're now going
to medical school their is not much reason to keep paying the subs. each
year.
You also get a list of ethical guidlines in the first issue of ACS
journals each year but I think these must be in some undecipherable
code.
Mike
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Subject: Re: Missing Plutonium
From: Gregory Greenman
Date: Tue, 21 Jan 1997 22:25:57 -0800
Dennis Nelson wrote:
>
[snip]
> What about the "subcritical" hydrodynamic experiments which were being prepared
> for detonation at the Nevada Test Site prior to Pres. Clinton signing the Nuclear
> Test Ban Treaty?  These use so-called subcritical, i.e. very small (possibly on the
> order of 80 grams) masses of Pu, can still produce a not inconsiderable yield, on
> the order of 0.5 to 1 KT.  Five hundred to a thousand tons of TNT can still make
> a pretty big hole.
> 
> Dennis Nelson
Dennis,
  Once again you demonstrate that you don't understand the science.
Subcritical does not mean very small, as you stated above. 
Subcritical means below critical, that is the physical configuration
of the system will not permit a self sustained chain reaction.
As an analogy, try to imagine attempting to set fire to some paper
in a container, the atmosphere of which is too oxygen poor to 
support combustion. The paper will not ignite; the fire will not
"catch".  Since the paper will not catch fire, it will NOT burn,
and hence will NOT release energy.
In a subcritical system, a self sustained chain reaction is 
physically impossible; the "nuclear fire" will NOT "ignite",
if you will. Therefore, it does NOT RELEASE ENERGY!!  You don't
get kiloton yields from a subcritical system!
For a better understanding of U.S. policy with regard to the
Nuclear Test Ban Treaty, I suggest you check out the following:
     http://www.dp.doe.gov/scibaste.htm
Dr. Gregory Greenman
Physicist LLNL
Standard Disclaimers apply
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Subject: Re: Vietmath War: If US had been parliamentary, no Vietnam war?
From: Alison Brooks
Date: Tue, 21 Jan 1997 07:16:24 +0000
In article <853586066snz@greenoak.demon.co.uk>, Tom Burke
 writes
>
>Quite a good debat, actually, as I recall, with contributions from people that 
>you would not normally expect to support the government, eg Jim Callaghan, Dr 
>Deat^H^H^HDavid Owen, and various others - there was indeed "all-party" support 
>for the government. I think the only dissenting voice was Tony Benn.... Chris, 
>am I right on that? And what's your take on this?
>
Tam Dalyell was also agin it, IIRC.
But, by and large, there was all-party support for the Government at the
debate, which was almost uniquely held on a Saturday.
-- 
Alison Brooks  
O-
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Subject: Re: This is impossible
From: drake.79@osu.edu (Macarthur Drake)
Date: 22 Jan 1997 06:32:30 GMT
>He was wrong,
>and they were right, but he was lucky that there was a previously
>unknown (except to the Vikings) continent between Europe and Asia to
>the east. 
>Evanston Illinois
	I am sorry, but you are wrong. The continent of America was 
enhabited by a variety of people, so of which produced very advanced 
civilization (Mayans for example) and presumably those people knew about the 
continent they live on. Sorry to nit pick you, but you did just discount a 
few million people who lived here BEFORE Columbus.
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Subject: ** structure of reality ** article 1 -revised
From: gary.forbat@hlos.com.au (Gary Forbat)
Date: 22 Jan 97 15:13:58
First draft revised 20-1-97
Notes on the Structure of Reality.      article 1.  
(2nd draft)
by Gary Forbat
Copyright (C) G. Forbat  1996
In these times of constant change and rapid development it is not often 
that we have time to reflect on the fundamental questions about reality. 
Descartes had long ago showed that the first evidence of reality is 
our personal consciousness. We become aware of a world of perceptions, 
and in the phenomena presented by the senses we become aware of some 
sort of regularity in the world that appears on the outside of 
introspection. As we now know, there is a huge gap between Descartes' 
certainty proposition and the proof of an 'outer' reality. To arrive at 
some sort of credible confidence in an objective material world requires 
a fairly long and sometimes arduous sequence of arguments, with serious 
challenges along the way posed by sceptics, who criticise the validity 
of our methodology and logical approach, phenomenalist, who reject the 
'outer' environment altogether, and others, among who are those who 
claim that an 'outer' reality does exists, but our images of it represent 
something quite unlike what they seem at face value to be. At this stage 
of proceedings I do not propose to get involved in these debates, other 
than to mention that after having considered all these contrary views, 
and the arguments put forth to support them, I duly dismiss them in favour 
of the scientific realism I espouse. 
My aim at present is to provide a fairly conscise outline of a theory 
of reality which can deal with most of the deeper questions that have 
so far eluded us. The starting point I choose is where the philosophical 
enquiry leaves off: with the affirmation of the existence of the physical 
world, that is, the existence of a reality on the outside of consciousness,
and that our sense impressions of it bears a close representative 
correspondence to the way things are in it. I suppose these are the initial 
presuppositions of the theory, though I emphasise again to have already
critically evaluated them. Apart from this beginning I wish to make no 
further assumptions, and will continue onward to draw all further 
conclusions in relation to well established observational premises. 
As things stand at this stage, we have reached affirmation of the material 
environment, but there has been nothing derived about its specific nature. 
The approach is from a narrowing generality so the first task is to find 
the most general features of this physical reality. In considering the 
evidence, perhaps the first and most obvious common feature is the 
presence of three dimensionality. A little thought about continuity 
and endurance can add the fourth dimension as time in fusion with it, 
but it is ofg little significance for the point to be presently 
established. I am well aware of a number of debates on dimensionality, 
and shall have the opportuninty to deal with them in the due course of 
these proceedings as difficult evidence challenges the logical system 
of the intuitive framework. But for now the task is to establish 
further general features. 
In analysing the evidence we find two types of things sharing  
three-dimensionality. One is the occurence of space without 
the consideration of matter, the other is matter itself. The existence 
of energy and its role in the scheme of things is not immediately evident, 
though a solution presents itself quite readily as will shoertly be seen. 
So far we have established three-dimensionality, but some regions 
contain what appears as emptiness, whilst others contain what appears 
as substance. Only some regions contain matter, but it is not at all 
clear whether space also underlies these regions or whether space is 
actually displaced where matter exists. If space did underlay these 
regions then matter does not actually 'displace' space, but rather 
'occupies'it. This would mean that spatiality is a more general aspect 
of physical reality than matter, with matter dependent on space but 
space not being dependent on matter. Intuitively this may seem simple 
enough, but nowadays the very mention of the word 'intuition' creates 
an impression of triviality. Indeed, the present generation has sunk 
so deeply into the web of abstraction that it may be difficult to 
extricate it from its entrenched confusions. 
We can now arrive at a definition of space as an enduring three 
dimensionally extended room in which material resides and an evolution of 
material events occur. If that is the case, then space as a domain 
of emptiness merely provides the room for material and cannot interact 
with either the matter or the energy that is found within it. As for 
energy, it is well known that matter and energy are mutually interactive, 
even interchangeable, so that these two aspects must form a single entity 
in varied forms. If I may then, for the sake of clarity, call tangible 
matter as 'matter' and non-tangible sources such as energy its 
'processes'. So then, we have matter and its processes operating 
within the spatiality provided. For all that, we have hardly touched 
upon specifics of either of these elements. But it seems, spatiality 
and matter should be subject of separate analysis, with space taking 
precedence as the more general aspect. 
( During 1995 I published an essay on spatiality. I will now refer the 
reader to it and will post this article separately. Article two of this 
series will assume familiarity with this essay )
G. Forbat
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Subject: ** structure of reality ** article 3
From: gary.forbat@hlos.com.au (Gary Forbat)
Date: 22 Jan 97 15:15:08
31-12-96
revised 1-1-97
Notes on the structure of reality - article 3
(first draft)
by Gary Forbat
Copyright (c) G. Forbat 1996
It may now be convenient to extend and qualify some of the main 
concepts derived from the theory. In the previous essays I described 
a process of material formation which provides the basis for the 
observed material reality. The process operates through a building 
procedure which involves a relationship between the physical 
magnitudes of structures, that is, the volume they occupy, and the 
rapidity of their internal cycles. Moreover, the process is universal, 
ranging over an infinity of scale tranformations from the most 
miniscule sizes to the most gigantic imaginable, in fact infinite in 
both directions. 
But it is not a single dimensional process involving only scale. What 
is peculiar about the sequence is that the smaller structures of
the micro world are highly dynamic due to an extremely rapid internal 
cycle operating to hold it together, and the smaller the structure, 
the more dynamic it is. Dynamics refers to the rapidity of the 
cyclical pulse. As particles break down to the cyclical funtion of a 
number of smaller components, those components will have a 
significantly more rapid internal cyclical rate than those of the 
larger structure they contribute to forming. The atomic structure, 
for instance, comes into being due to the cyclical function of the 
electron in relation to the nucleus. The composition of the electron 
has not yet been penetrated, but the possibilities are few. Either it 
is composed of a very large number of tiny parts, or maybe fewer but 
of a much higher dynamicity. The nucleus, on the other hand, is known 
to break down to combinations of smaller, but much more dynamic parts
known as 'quarks'. Quarks themselves must reduce to even smaller 
components, with cyclical rates of increasingly more rapidity. The
many qualities of quarks testify to a variance of configurations. 
The quantum proportions testify to this very nature. With the 
process of reduction infinite, so with it is the increase in 
dynamicity. 
We are fortunate enough to be able to observe two vastly different 
aspect of the material process. The micro scales of phenomena present 
an integrated view of average behaviour over many billions of cycles. 
Imagine how the solar system would look if billions of planetary 
cycles were pressed into a single second. Theoretically at least, it 
would be possible to simulate the effect by taking a long term video 
of the solar system in motion over many billions of years, and then 
replaying the tape over a matter of seconds. Undoubtedly we could 
make computer image simulations of it much more easily. 
Then there is the almost static view of the process presented 
by the structures of the large scale in their 'real time' cyclical 
movements. Our viewpoint of stellar formations is fashioned from the 
workings of the atomic structure, and compared to the speed and 
capacity of the functioning of our instruments and sensing apparatus, 
the stellar structures are both extremely large and so slowly evolving 
as to be almost static. But now, let's venture to reconstruct in its 
broadest principles the consequences of this infinite sequence of 
structuring, not only to determine the status of our own viewpoint 
within it, but to attempt to discover general principles that may be 
directly affecting us and we are not yet aware of. Firstly, going up 
or down in scale, the specific attributes of structure types that 
occur depend on the interactive possibilities afforded on each  
particular scale. Solar systems of one type or another, whether 
binary or planetary are the almost exclusive forms that may be found 
at the scale of the direct interaction between the most massive 
atomic conglomerations. At this scale of consideration the universe 
can be seen to be interspersed with stellar and planetary matter in 
mutual interaction as solar systems. But we know that solar systems, 
in turn, almost exclusively congregate in the larger massive 
formations of galaxies, occuring in a small number of types. Galaxies 
themseves form clusters with unique characteristics types of their own. 
On the galactic scale of consideration the universe can be seen as 
interspersed almost exclusively by galactic formations. Certainly they 
are the only long term stable forms to be found at this scale. 
In fact we can apply this principle at any level of magnitude. Thus
the universe is interspersed by atoms at the atomic scale of 
consideration but with planetary/stellar matter on a larger scale.
So then, as the process builds to infinity, with each structure type 
occuring in forms and attributes appropriate to interaction and 
formation possibilities at that scale, each transformation produces 
unique structure types, and there is certainly no likelyhood of the 
same structure type occuring at different levels either in the micro 
and macro scales. 
Both the reduction and its reverse process of expansion runs to infinity,
with the roots of each or any structure traceable in infinite steps
toward smaller scales. But this does not work in the reverse toward the
macro. The reason is that not all structures continue to build outward 
forever. Large sections of it terminate at a certain level, as in the 
case of the structures that intersperse in our seemingly empty spatial  
regions. My findings are that these regions are far from empty. 
The entire spatiality in fact contains a fine invisible mist of matter, 
structured at its highest level to an interactive fabric to form 
a micro infrastructure which sets the framework for the workings of 
our atomic based material environment. But only those elements
which participate in further building processes to form the atomic 
base can get through to build outward to form structures on larger 
scales. The rest, indeed a very large portion of micro material,
is lost to further structuring. In this infinite chain of 
expansions it should be expected that terminal stages are reached 
from time to time. Nevertheless, what remains after each of these 
mass terminations is still adequate to reconstruct other equally 
thickly populated levels of structures on much larger scales.    
So what is the status of our material system amid this infinity of 
transformation levels ? On the micro end we observe the process through
a very high integration, but on the macro end it tends toward static. 
With the two directions reflecting merely different aspects of a 
single process, our observational access results from the circumstances 
of our evolution as sensing beings and our relation to the material 
interaction that brought it about. We are a direct product of our 
micro infrastructure and the atomic base. The question remains 
whether ours is the only material environment possible or whether
there may be others ? Perhaps other configurational circumstances can 
exist among an infinity of types which produces alternative material 
bases. 
We need firstly to examine the general circumstances which must be 
present for a material environment. Obviously the most evident 
is the versatility of our atomic structure. It is extremely stable 
and durable with a systematic regularity as well as being greatly
variable in chemical combination. It is truly like a wonder particle 
which goes on to create a tremendously varied and interactive world 
of material activity to which we all bear witness. Surely it would 
be fairly rare to find a scale level of structuring where such a 
useful type of particle is found. Nevertheless it stands to reason 
that in a infinite chain of transformations other similarly efficient 
structure types are bound to occur. some may indeed be even more 
flexible than the atom, or perhaps somewhat less so,  but still able 
to generate a causal evolution in its conglomerate forms to create an 
alternative material environment rivalling ours. Of course on the micro 
scales a funtional world would evolve extremely rapidly compared to 
ours, and on the macro scales the events would take on gigantic 
proportions, evolving very slowly by our way of looking at it. 
G. Forbat
to be continued in the next article                      
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Subject: Re: Viper/Porsche: time, speed, distance
From: Jack Mott
Date: Tue, 21 Jan 1997 23:24:38 -0500
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Chuck Tomlinson wrote:
>
> On 21 Jan 1997 17:50:37 GMT, Gary Kercheck wrote...
> >
> >lparker@curly.cc.emory.edu (Lloyd R. Parker) wrote:
> >
> >>because I pointed out a flaw in your reasoning?
> >
> >There is no flaw.  My formulas accurately represent the distance
travelled
> >by each vehicle in the 4.8 seconds it takes the Porsche to reach
130mph.
> >The difference in distance is about 23 feet.  You calculated 146
feet.
>
> In the hope of settling this issue, I crunched some numbers today and
> discovered a few things:
>
> ** Summary **
>
> First, C&D; was wrong when they said the Viper would be ahead by more
than
> 260 ft at 130 mph.  What they should have said is that the Viper
reaches
> 130 mph in 260 ft less distance than the Porsche.  My analysis (which
I'll
> explain later) shows that the Porsche needs 2,186 ft to reach 130 mph
and
> the Viper needs 1,920 ft.  That's a difference of 266 ft in Viper's
favor.
>
> Second, between the time that the Viper finishes the QM (12.3 sec) and
> the time it reaches 130 mph (15.7 sec), it has closed the gap to the
> Porsche by a not-so-spectacular 20 feet (in fact, the Viper is
alongside
> the Porsche). The Porsche is going 126 mph at this point.
>
> By the time the Porsche reaches 130 mph (17.1 sec) the Viper is going
> almost 135 mph, and has pulled out another 8 ft on the Porsche.
>
> Third, even allowing for some calculation error, the Viper and Porsche
> are within horn-honking range (if not fender-tapping range) of each
> other at 130 mph.
>
> ** Method **
>
> Using Microsoft Excel's Solver add-in, I fitted a curve to the speed
vs
> time plot for each car.  For the Viper, I used the curve from C&D;
9/96.
> For the Porsche, I used the times from the 7/95 C&D;, filling in
> intermediate speeds based on the curve from the 6/95 Motor Trend.
BTW,
> the 20.5 sec 0-150 mph time in C&D; 7/95 is clearly wrong.  My
curve-fit
> suggests it should be 25.0 sec.
>
> The equation I fitted to the curves had the form:
>
> Speed = (C1 * t^E1) + (C2 * t^E2) + (C3 * t^E3),
>
> where C1..C3 are constant coefficients, and E1..E3 are exponents
applied
> to the time variable.  After some frustration with setting up the
solver,
> I fixed E1 = 0.40 and E2 = 0.75, then let the solver find the other 4
> unknowns by minimizing the sum of the squared errors.
>
> After the coefficients and exponent were found, I plotted distance vs
> speed for each car by integrating the above equation for speed.  As a
> reality check, I used the goal seek function to find the time required
> to cover 1320 feet (quarter mile).
>
> ** Results **
>
> Each fitted speed curve matched the published curve within about 1 mph
> over the full speed range.
>
> For the Viper:
>
> Speed(mph) = 430.86 t^0.71602 - 352.96 t^0.75 - 60.158 t^0.40
> and 0-1320' in 12.3 at 116 mph
>
> For the Porsche:
>
> Speed(mph) = 357.75 t^0.72183 - 303.66 t^0.75 - 29.962 t^0.40
> and 0-1320' in 12.3 sec at 113 mph
>
> ** Conclusions/Recommendations **
>
> I am confident that this method generates a fitted curve that is at
> least as accurate as the published test data.  This method is readily
> available to anyone with access to later versions of MS Excel.  And
> IMHO, it's a helluva lot better than endless handwaving and
questionable
> assumptions.  Try it and see.
>
Now lets put the Porsche and the Viper on a road race and see who comes
out on top.  See if you can put sears point into that spreadsheet :)
(my bet: Porsche wins because of better brakes or endurance if its a
long race)
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Chuck Tomlinson wrote:

> On 21 Jan 1997 17:50:37 GMT, Gary Kercheck wrote...
> >
> >lparker@curly.cc.emory.edu (Lloyd R. Parker) wrote:
> >
> >>because I pointed out a flaw in your reasoning?
> >
> >There is no flaw.  My formulas accurately represent the distance travelled
> >by each vehicle in the 4.8 seconds it takes the Porsche to reach 130mph.
> >The difference in distance is about 23 feet.  You calculated 146 feet.

> In the hope of settling this issue, I crunched some numbers today and
> discovered a few things:

> ** Summary **

> First, C&D was wrong when they said the Viper would be ahead by more than
> 260 ft at 130 mph.  What they should have said is that the Viper reaches
> 130 mph in 260 ft less distance than the Porsche.  My analysis (which I'll
> explain later) shows that the Porsche needs 2,186 ft to reach 130 mph and
> the Viper needs 1,920 ft.  That's a difference of 266 ft in Viper's favor.

> Second, between the time that the Viper finishes the QM (12.3 sec) and
> the time it reaches 130 mph (15.7 sec), it has closed the gap to the
> Porsche by a not-so-spectacular 20 feet (in fact, the Viper is alongside
> the Porsche). The Porsche is going 126 mph at this point.

> By the time the Porsche reaches 130 mph (17.1 sec) the Viper is going
> almost 135 mph, and has pulled out another 8 ft on the Porsche.

> Third, even allowing for some calculation error, the Viper and Porsche
> are within horn-honking range (if not fender-tapping range) of each
> other at 130 mph.

> ** Method **

> Using Microsoft Excel's Solver add-in, I fitted a curve to the speed vs
> time plot for each car.  For the Viper, I used the curve from C&D 9/96.
> For the Porsche, I used the times from the 7/95 C&D, filling in
> intermediate speeds based on the curve from the 6/95 Motor Trend.  BTW,
> the 20.5 sec 0-150 mph time in C&D 7/95 is clearly wrong.  My curve-fit
> suggests it should be 25.0 sec.

> The equation I fitted to the curves had the form:

> Speed = (C1 * t^E1) + (C2 * t^E2) + (C3 * t^E3),

> where C1..C3 are constant coefficients, and E1..E3 are exponents applied
> to the time variable.  After some frustration with setting up the solver,
> I fixed E1 = 0.40 and E2 = 0.75, then let the solver find the other 4
> unknowns by minimizing the sum of the squared errors.

> After the coefficients and exponent were found, I plotted distance vs
> speed for each car by integrating the above equation for speed.  As a
> reality check, I used the goal seek function to find the time required
> to cover 1320 feet (quarter mile).

> ** Results **

> Each fitted speed curve matched the published curve within about 1 mph
> over the full speed range.

> For the Viper:

> Speed(mph) = 430.86 t^0.71602 - 352.96 t^0.75 - 60.158 t^0.40
> and 0-1320' in 12.3 at 116 mph

> For the Porsche:

> Speed(mph) = 357.75 t^0.72183 - 303.66 t^0.75 - 29.962 t^0.40
> and 0-1320' in 12.3 sec at 113 mph

> ** Conclusions/Recommendations **


> I am confident that this method generates a fitted curve that is at
> least as accurate as the published test data.  This method is readily
> available to anyone with access to later versions of MS Excel.  And
> IMHO, it's a helluva lot better than endless handwaving and questionable
> assumptions.  Try it and see.


Now lets put the Porsche and the Viper on a road race and see who comes out on top.  See if you can put sears point into that spreadsheet :)
 
(my bet: Porsche wins because of better brakes or endurance if its a long race)
 
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Subject: Elastic collisions
From: Duane Morin
Date: Tue, 21 Jan 1997 10:12:07 -0500
Hi,
I promise this isn't a homework question - I haven't been in school for
years now :).
While learning a new computer language over the weekend, I found a demo
of a ball bouncing around.  And I thought to myself "Hey, self, what if
you added another ball to that and let them bounce around together.  How
would you model collisions?"
So that's the question, because it's apparently not as easy as it looks.
For the sake of argument, let's say we're dealing with point masses
A and B, each with a given mass, velocity, and vector (in 2 dimensions).
Also assuming no additional forces such as friction, and no loss of
energy during the collision.  The two are going to hit, and then go
shooting off in different directions.
How would I model the resultant exit vectors of each of the particles?
Duane
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Subject: Tenure? On the whole, yes. Was: ABOLISH ACADEMIC TENURE
From: "Arthur E. Sowers"
Date: Tue, 21 Jan 1997 22:21:36 -0500
Mike gave us his anti-tenure thoughts without giving us his situation
vis-a-vis the subject. I have seen, in my days, tenured faculty who
exemplified the epidomy of lazyness, arrogance, unreasonableness, and
being generally out-of-touch-with-the-world. I have met secretaries,
janitors, and members of our military that were better human beings than
some profs. Academia (and its culture) has its own peculiar version of
"rot" which alows a lot of unfairness be perpetuated (I have on
my web page a series of essays devoted to parts of this situation). If
anyone, mark my words, will compare the fraud, deceit, lies, chicanery,
and malfeasance on campuses with what goes on in the
industrial/commercial/government cultures, then it is miniscule by
comparison. People who are rich can often get away with murder (and other 
crimes), figuratively or literally. There are many many books written
about these areas and if Mike really wants to get mad about something,
I'll post some titles for him to read.
Pure academic campuses are where a tenured prof may enjoy a
status which is highly "protected." However, that, and the priveledges
Mike refers to below, do not tell the whole story.  First, tenure, per se,
does not mean permanent employment in many many cases. Many many campuses
are, or already have, watered down tenure to the point where it means very
little (this is also covered in my essays on my web page). In a large
number of cases, tenure may be associated with the "appointment," only.
Its relationship to the salary is quite another thing. At a large fraction
of the better schools, at least a minor fraction comes from grant money.
For many faculty, 100% of the salary comes from grants. What good is
tenure if one's salary drops to 10-20% of "normal?" This situation, as far
as I have been able to determine is the case for a significant fraction of
the faculty at medical schools (medical school faculty account for about
10% of all faculty [USA statistics]). The situation in many
non-medical health science schools is similar. And, tenure-track positions
are being abolished for new faculty at many campuses and being replaced
with "postions" which are tenure-eligible, but I know from people in some
of these departments that chairs have been not recommending tenure for
many years.
At non-medical schools, what is happening is that many faculty are being
hired in non-tenure track or "adjunct" postions which have lower pay,
little or zero fringe benefits, and are characterized with zero job
security (their appointment may not be renewed and no reason need be given
for this regardless of how well they perform; most people, in general, are
not aware that even in tenure-track positions, a chair can usually
terminate a faculty member with approximately zero (if you count minutes) 
notice (I have heard of several cases and have documentation for this) and
this having nothing to do with performance, but politics (eg. the faculty
member did something to piss off the chair). I know of one case in a
medical school where a new chair came into the department and literally
fired the whole faculty (obviously no one had tenure) lock, stock, and
barrel.
So, this is the purpose of tenure. Chairs have incredible power and deans
almost never (oh, maybe 0.0001% of the time) meddle with a chair's
operations (I can cite maybe two cases where I know of publication of the
information and I know of a couple of cases where the removal of a chair 
was hushed up very effectively). Again, this is more in health science
campuses, but I have heard similar stories from departments at some of the
most limelight of campuses. 
I have a faculty handbook which devotes extensive space to how much
professional commitment a faculty member MUST have towards his/her
institution, but there is practically nothing about any commitment on the
part of the institution towards the faculty member (except for annual and
sick leave). I would like to go into some detail about this someday.
But, I favor tenure (and not just in appointment, but also for a
significant fraction of the FTE salary) because:
To become a prof at any worthy institution requires not only grad
school to a PhD (or other Dr degree), but usually at least 4-5, and up to
10 years of postdocing. We're talking about major commitment and devotion
of a very large part of ones best adult years (not to mention possible
debt financing) to preparation for devoting a lifetime to an indepth
study. Although this is primarily for the sciences, I respect all other
intellectual endeavors as well (arts, music, humanities, etc.). Why should
one piss away their life for stupid one year appointments? Uncertainty of
grant renewal in the sciences. And when the grant funding does not get
renewed, the guy in question gets dumped down the chute into the trash can
without even a going away party AND finds that the outside
industrial-commercial world will probably view him as overqualified for
almost everything from McDonald's burger flipping and Wal-Mar floor people
on up. 
Try to think of nonfaculty people who have job security and good
paycheck security that are above that of most faculty and are also not
accountable. I can think of many corporate officers, employees within our
law enforcement infrastructure, a large fraction of our military
personnel, and many support staff infrastructures, to name a few. I think
if we add all of these up, we will find a much larger population of people
with all of the characteristics Mike listed for his "model" tenured prof. 
Thank you for your time and attention,
Art Sowers
-------------------------------------------------------
Written in the public interest, the essays on 
"Contemporary Problems in Science Jobs" are located at:
http://www.access.digex.net/~arthures/homepage.htm
Snail mail adr to me: P.O.Box 489, Georgetown, DE 19947
-------------------------------------------------------
=== no change to below, included for reference and context ====
On Mon, 20 Jan 1997, Dettol wrote:
> DOES ACADEMIC TENURE HAVE ANY PLACE IN THE MODERN WORLD?
> 
> I find the whole idea of someone being given a job for life abhorrent
> but I think what irritates me the most about academia is the lack of
> accountability of tenured staff.
> 
> I'd like to hear if anyone knows of a tenured academic who has been
> sacked for poor performance.   I am personally aware of two academics
> who have been sacked [one broke the law (theft of university property)
> and the other was "invited to retire" rather than face a harassment
> suite] but none who have even been discipline for poor performance.
> 
> What is so special about academics that they deserve privileged
> treatment?  The idea of a job for  life has been tried in the broader
> community and has failed.  The reasons for the failure are generally
> given as lack of incentive, lack of competition, lack of efficiency and
> productivity and so on.
> 
> Isn't it time we abandoned failed socialist ideas of a job for life?
> 
> When discussing this issue with others the point is often raised what
> criteria should be used to assess performance.   Also it is often
> suggested that poor performers exist in the real (ie, non-academic)
> world.
> 
> As a first instance could I suggest a minimum requirement of turning up
> to work for at least twenty hours a week.  I'm sure failure to turn up
> for work would result in dismissal in private industry.  I have been
> associated with three academic chemistry departments and this criteria
> alone would result in three staff members being sacked.  At the moment
> of course they are tenured and therefore accountable too no-one.  The
> off-the-record  feeling of others in these departments is that there is
> nothing that can be done so just ignore the problem and try not to make
> the same mistake when hiring the next time.
> 
> Admittedly academic absenteeism is probably only a problem in a
> relatively small percentage of cases but it highlights the lack of any
> systematic accountability.
> 
> I think a far worse and endemic problem is fraud.  I'm choosing to use
> the word in its broadest sense.  Perhaps "parafraud" is a better word. 
> It is the word used by Harold Hillman in an article published in The
> Times Higher Education Supplement (1995) titled "Peccadilloes and Other
> Sins" to describe a multitude of academic "sins" some of which included
> :
> "research workers who do not report their own experiments or
> observations that are incompatible with their beliefs.
> 
> Academics who do not quote publications who's conclusions they do not
> like.
> 
> Scientists who do not carry out the relevant control experiments either
> by omission or refusal to do so, when attention has been brought to
> them...
> 
> Some supervisors expect to share in authorship of research work in which
> they have made little or no intellectual contribution..."
> 
> It is this final point that I think is the most widespread.
> 
> The current system of reward in academia encourages quantity rather than
> quality of research publications.  I'd like to take a hypothetical
> example of an academic who works diligently during their initial years
> of academic appointment.  Through hard work and flair in their field
> they may attract research funds which in turn enables them to attract
> graduate students and, if the researcher publishes and gains more
> recognition (= more funds), post docs.  There reaches a stage when a
> research group has enough graduate students and postdocs for the whole
> process of engaging in scientific research to be self propagating
> without the need for input from the principal investigator (PI).  
> 
> At this stage the PI faces a moral dilemma.  One can become an absentee
> PI, turn up for work very now and then and still watch one career flower
> due to the output of the laboratory or the PI can continue to
> participate actively in the process.  Sometimes a problem exists in that
> despite the best intentions of the PI the research group becomes too big
> for the PI to have a realistic input to all projects.  In this case and
> more so in the case of the absentee PI they are needed solely to sign
> purchase orders.  My point here is that these people have become
> glorified lab managers and are no longer needed for the scientific
> process to continue (other than getting their signature on a PO).  
> 
> I think that without tenure this situation would be less likely and
> where it existed the university would be able to dismiss the faculty
> member and appoint someone else.
> 
> The next thing that often gets raised when I have this discussion is
> that in the situation that I have described (and witnessed) the PI is
> still productive based on the only measure of productivity that seems to
> exist in academia, namely quantity of publications.
> 
> This is where a huge reform in attitude is necessary.  Recall the final
> point that I quoted from  Hillmans article.  I've asked people why
> such-and-such a person was listed as a co-author when they have made no
> scientific contribution.  A typical response is that "they raised the
> money."
> 
> For those of you who are chemists check out the ACS ethical guidelines
> for publication (I'm sure the other societies have similar).  It is
> quite clear in those guidelines what constitutes authorship and what
> doesn't.  Raising the money does not constitute grounds for authorship. 
> If it did a philanthropist could choose to fund research projects and
> very soon become the most published scientist of our time.  
> 
> The problem that is rampant in academia is that PIs take credit and
> co-authorship when they do not ethically warrant it, and thereby
> increase their quantity of publications, enhance their reputations and
> make funding all the easier to acquire the next time.  And so the cycle
> continues and a PI can build a 30 year career by turning up to work in
> the first ten years.
> 
> At the moment it is a foolproof system.  No accountability exists.  The
> people in a position to observe this parafraud, the graduate students
> and postdocs, depend on the PI for their salary but perhaps what is more
> important they depend on the PI for a reference for future employment. 
> Why be a "whistle blower?"  You are only there for a few years, it is
> too easy not to rock the boat.  
> 
> PIs will continue to be "raising the money" and paying graduate students
> and postdocs and churning out quantities of papers and raising more
> money and so on...
> 
> The cycles continues and  academia has lost its way.
> 
> 
> Mike
> 
> 
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Subject: Re: "Draw" an electron, you may win fabulous prizes.
From: ale2@psu.edu (ale2)
Date: 22 Jan 1997 07:33:36 GMT
In article 
lockyer@best.com (Thomas N. Lockyer) writes:
> 
> I can't resist commenting.
> 
> Your rules are not restrictive enough, so you will attract ideas that are ad 
> hoc.
Feel free to enter the contest with your ideas %^)
> 
> See the correct models in this URL:
> 
> Regards: Tom:  http://www.best.com/~lockyer/home3.htm
Nope, you have to enter to win!
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Subject: Vietmath War; The Killing Fields
From: Archimedes.Plutonium@dartmouth.edu (Archimedes Plutonium)
Date: 22 Jan 1997 06:06:52 GMT
THE KILLING FIELDS, 1984,
When the Khmer Rouge captured the Cambodian capital in 1975, many
thought the killing would end. But it was only the beginning of the
long nightmare in which three million of Cambodia's seven-million
people would lose their lives in "the killing fields."
...
Dith is Shanberg's Cambodian aide, translator and friend who saves
Schanberg and other Western correspondents from execution. But the men
he saves cannot in turn save him.
...
  The Killing Fields which won three 1984 Academy Awards...
---------
THE P-adic Integer FIELDS, 1997
When the finite integers people captured the worlds capitals back in
ancient civilization and up to now, many thought the finite integers,
each had an end. But it was only the beginning of the long learning
experience of mathematics in which everyone will eventually understand
that  "the p-adic integer fields " are the Natural numbers and not some
half baked notion of "finiteness".
...
P-adic series is the Peano Successor axiom. But the finite integers
just cannot stop , cannot help but go into infinite species of
integers, the p-adic integers.
...
  The P-adic Integer Fields as the Natural numbers will not win any
prize until the  math people who control the present day math journals
and education give up their lucrative money grub stranglehold on the
math community ... and debate this new idea -- Naturals are the
Infinite Integers.
 Since all 3-adics have multiplicative inverses except for the prime
itself of 3, implies that each 3 adic except 3 has a dual. This implies
that prime-adics have a harmonic oscillation like a foucalt pendulum. A
forward swing is a 3-adic and the backward swing is the multiplicative
inverse of the forward swing.
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Subject: Re: ABOLISH ACADEMIC TENURE
From: Post.To.NewsGroup.NOT@email.thanks (Troy Shinbrot)
Date: Wed, 22 Jan 1997 01:34:32 -0500
In article <32E5B2A8.13CA@gold.chem.hawaii.edu>, Dettol
 wrote:
> > 
> > Let us imagine that you are a scientist, and you have an idea that
> > requires more than 6 months to execute.  Into this category fits a great
> > plurality, at least, of important work being carried out in any of the
> > sciences.  How, without tenure, would you support yourself while this work
> > is being done? 
> 
> The same way untenured faculty members currently support
> themselves!!!????
You will find exceedingly close to zero untenured faculty who can survive
by pursuing long term research.  Untenured faculty are evaluated, and
permitted to continue, based on short term achievements.  If you want only
short term science to be done, abolishing tenure is the way to achieve
your goal.
-Troy
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Subject: Re: PHYSICS RELATED JOBS
From: ale2@psu.edu (ale2)
Date: 22 Jan 1997 07:50:31 GMT
In article <5c35jn$q4c@news.interlog.com>
peter@web-spinn.com (Peter) writes:
> Hi there:
> 
> I am a recent physics graduate, I'm wondering if anyone could help me find 
> work relating to physics.  Where do you look, on the web, newsgroups, 
> newspapers?
> 
For starters check the thread on sci.physics, "Re:PH.D.s are useless"
Then try and get your "foot in the door".
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Subject: Re: Mach's Paradox?
From: 74553.2603@compuserve.com (Michael Ramsey)
Date: 22 Jan 1997 04:10:35 GMT
In article <853842965.471095@red.parallax.co.uk>, 
paddy.spencer@parallax.co.uk says...
>> [snip]
>>which today's physicists won't do without even though it is
>>incompatible with the thoroughly-tested Quantum Mechanics.
>
Cramer's Transactional Interpretation of Quantum Mechanics explains all
of the weird quantum features by connecting the particles (e.g.) electrons in 
your eye with the particles (e.g. electrons) in "the distant matter" by 
introducing a transaction involving forward and retarded waves which 
communicate backwards and forward in time.  The transaction appears to us as 
happening in zero time.  TI incorporates and explains Mach's Principle 
directly, and beautifully.
Read Cramer's paper.  
   http://mist.npl.washington.edu/npl/int_rep/tiqm/TI_toc.html
The heterodox is becoming the orthodox.
--Mike 
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Subject: Re: This is impossible
From: rdadams@access4.digex.net (Dick Adams)
Date: 22 Jan 1997 02:24:20 -0500
Macarthur Drake  wrote:
>> He was wrong,
>> and they were right, but he was lucky that there was a previously
>> unknown (except to the Vikings) continent between Europe and Asia to
>> the east. 
>> Evanston Illinois
>	I am sorry, but you are wrong. The continent of America was 
>enhabited by a variety of people, so of which produced very advanced 
>civilization (Mayans for example) and presumably those people knew about the 
>continent they live on. Sorry to nit pick you, but you did just discount a 
>few million people who lived here BEFORE Columbus.
Alas we have a whole new definition of discovery.
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Subject: Info on bacteriorhodopsin
From: "Melvin M. Moriwaki"
Date: Tue, 21 Jan 1997 21:26:26 -0800
I would appreciate it greatly if anyone knows whom to contact or 
references regarding the optical or general properties of 
bacteriorhodopsin for a junior high school project.
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Subject: Re: This is impossible
From: Bill Wines
Date: 22 Jan 1997 07:38:14 GMT
In article <5bsc70$f1d@csu-b.csuohio.edu> Macarthur Drake,
drake.79@osu.edu writes:
>From my  understanding of biochemistry and the number of stars in the
universe....to 
>not find life would be the greatest discovery of all times. There is
nothing 
>extraordinary about looking the biochemistry of life and looking at the 
>billions of stars (in this galaxy alone) and concluding that there MUST
be 
>life out there. 
I disagree.  From the modicum of reading I've done in this area (and I'm
not a scientist, just one of those "educated laypersons") I find it
interesting that biochemists tend to be a lot more skeptical about E.T.'s
than astronomers or astrophysicists.  
>From a scientific view, there is nothing unique about amino 
>acids.....the elements that make them up are not located only on this
planet 
>for sure. 
This may be so, but it's not the mere existence of amino acids that's at
issue.  It's the probability involved in the particular combinations of
amino acids and the subsequent evolution of self-replicating enzymes. 
This likely involved a series of discrete events, subjected to the
environmental pressures of natural selection unique to the environment of
the earth at a particular stage in its development.  A lot of biochemists
would argue that these events were essentially accidents.
>Now if there were only 10 stars in the entire universe the Dr. 
>Sagan's stament maybe more logical. But we can say, based upon all our 
>scientific theories, that LIFE MUST  exist elsewhare in the universe. If 
>not, then everything we understand about the universe is false.
So now you've gone from the likelihood that life exists elsewhere to the
"necessity" for it to exist elsewhere.  I detect some wish-fulfillment
going on here.  The "scientific" views on this subject are very diverse. 
There's nothing in the current scientific understanding of the universe
that compels one to prefer one view over the other.   The fact that most
people seem to take it for granted that there "must" be intelligent life
elsewhere seems to me to be based on an unreasoning awe at the sheer
immensity of space and the numbers of galaxies, plus a bit of "cosmic
loneliness."  
Bill Wines
School of Information, University of Michigan
Editorial Assistant, The Clearinghouse
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Subject: Re: Dif. between Math and Phys.
From: 74553.2603@compuserve.com (Michael Ramsey)
Date: 22 Jan 1997 05:46:43 GMT
In article <5c2etm$pdq@panix2.panix.com>, erg@panix.com says...
> [snip]
>In our standard phenomenological model of the world,  with standard
>assumptions,  physics is the discovery of the logical system of the
>world.   As in mathematics,  a single counter-example *in the
>substrate* is sufficient to repudiate any logical model,  or cause its
>modification.  A single experiment is not.  Repeated experiments with
>care to eliminate special causes generates a high degree of belief,
>just as repeated demonstrations of a proof generate a high degree of
>belief.  The logical necessity of zero counter examples for which a
>special cause cannot be assigned is really the same in each case.
>
>There is further analysis needed,  but that should be enough to spark
>violent disagreement.
Ed,
 mathematics starts with a syntax for constructing "well formed formulas"
wffs) and relations among the wffs called "rules of inference".  A subset 
of the wffs are considered to be axioms.  A proof is a sequence of wffs 
where each wffs in the sequence is either an axiom or is a consequence of 
a previous wffs by virtue of a rule of inference.
Mathematics doesn’t ask the question "Is this wff a valid representation of
the universe?"  One can construct mathematical models which clearly do not 
represent how the universe works and yet are wffs.
Physics is the enterprise of constructing wffs that are possibly true, and 
then performing experiments which ask the universe to decide which are in 
fact  true.  Since physics is concerned with interrogating the universe,
someone cannot tell if the person is reporting the truth by examining a
sequence of wffs.  Instead, they have to examine the experimental 
setup and the resulting data.  Physicist have been known to commit errors
of omission (Hint: cold fusion). 
Therefore, experiments must be independently repeated to make sure that 
systematic errors are not hiding the right answers.
In mathematics, an independent someone has to examine the sequence of wffs 
and insure that the rules of inference were properly applied.  The difference
is that in mathematics, you don’t have to build expensive apparatus to 
validate a proof.
I agree that "reductio ad absurdum" is a powerful tool in both physics and 
mathematics.  If a theory predicts that the universe will respond to an 
experiment in a certain way and it doesn’t, than a contradiction is proven 
and the theory must be revised.
--Best regards,
--Mike
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Subject: Re: FTL Comm
From: Sylvia Else
Date: Wed, 22 Jan 1997 19:29:02 -0800
Chuck Federspiel wrote:
> Now, if I had an FTL communicator, I would use it to alert the outer
> planets as soon as Sol goes super, just to give any colonists a few
> minutes to ponder their worthlessness.  I would do that a coupla times a
> week.
:) Nice idea.
Still, ignoring the fact that the sun is too small to go supernova, would 
they actually fall for this? How long do you have between the arival of 
the neutrino flux from the core, and the arrival of the electromagnetic 
flux from the surface, which I suspect would severly curtail your message 
sending abilities - FTL or otherwise.
Sylvia.
**** Sending me email? Note, my real email address is sylvia@zip.com.au, 
**** and not as specified in the header.
**** I consistently approach the administrators of systems from which I
**** receive junk mail.
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Subject: Re: "Draw" an electron, you may win fabulous prizes.
From: ale2@psu.edu (ale2)
Date: 22 Jan 1997 09:11:48 GMT
In article <5c4fsg$uvg@r02n01.cac.psu.edu>
ale2@psu.edu (ale2) writes:
> In article 
> lockyer@best.com (Thomas N. Lockyer) writes:
> 
> 
> 
> > 
> > I can't resist commenting.
> > 
> > Your rules are not restrictive enough, so you will attract ideas that are ad 
> > hoc.
> 
> Feel free to enter the contest with your ideas %^)
> 
> > 
> > See the correct models in this URL:
> > 
> > Regards: Tom:  http://www.best.com/~lockyer/home3.htm
> 
> Nope, you have to enter to win!
Oh, all right, i will take a look, but i can only give you honorable
mention if you don't choose to enter %^(
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Subject: Re: This is impossible
From: Bill Wines
Date: 22 Jan 1997 07:39:08 GMT
In article <5bsc70$f1d@csu-b.csuohio.edu> Macarthur Drake,
drake.79@osu.edu writes:
>From my  understanding of biochemistry and the number of stars in the
universe....to 
>not find life would be the greatest discovery of all times. There is
nothing 
>extraordinary about looking the biochemistry of life and looking at the 
>billions of stars (in this galaxy alone) and concluding that there MUST
be 
>life out there. 
I disagree.  From the modicum of reading I've done in this area (and I'm
not a scientist, just one of those "educated laypersons") I find it
interesting that biochemists tend to be a lot more skeptical about E.T.'s
than astronomers or astrophysicists.  
>From a scientific view, there is nothing unique about amino 
>acids.....the elements that make them up are not located only on this
planet 
>for sure. 
This may be so, but it's not the mere existence of amino acids that's at
issue.  It's the probability involved in the particular combinations of
amino acids and the subsequent evolution of self-replicating enzymes. 
This likely involved a series of discrete events, subjected to the
environmental pressures of natural selection unique to the environment of
the earth at a particular stage in its development.  A lot of biochemists
would argue that these events were essentially accidents.
>Now if there were only 10 stars in the entire universe the Dr. 
>Sagan's stament maybe more logical. But we can say, based upon all our 
>scientific theories, that LIFE MUST  exist elsewhare in the universe. If 
>not, then everything we understand about the universe is false.
So now you've gone from the likelihood that life exists elsewhere to the
"necessity" for it to exist elsewhere.  I detect some wish-fulfillment
going on here.  The "scientific" views on this subject are very diverse. 
There's nothing in the current scientific understanding of the universe
that compels one to prefer one view over the other.   The fact that most
people seem to take it for granted that there "must" be intelligent life
elsewhere seems to me to be based on an unreasoning awe at the sheer
immensity of space and the numbers of galaxies, plus a bit of "cosmic
loneliness."  
Bill Wines
School of Information, University of Michigan
Editorial Assistant, The Clearinghouse
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Subject: measuring LASER power
From: radman@teleport.com (r_guy)
Date: Wed, 22 Jan 1997 05:23:58 GMT
I've recently found my self in a situation where the power output of
some lasers must be measured.  Some probes have been located, but
can't seem to find  reliable DC instrumentation amps  to boost the
probe signals to a usable level.  AC amps don't drift like the DC
kind, but distorts the pulses enough to be a problem.    Anybody out
there have any experience with this?
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Subject: Re: I need help right away...
From: jxw654@anu.edu.au (J Wu)
Date: Mon, 20 Jan 1997 22:33:03 +1000
Your question is unclear. 
In article <01bbfe90$dc8e9c60$672818ce@consolidated.ccinet.net>, "Ryan
Vacca"  wrote:
> I'm sorry about the short notice, but if you are reading this post, and
> know anything at all about the subject please e-mail me right away.
> I need to know how and/or why an electromagnet works.  I have made one with
> 2-C batteries, about 3 feet of copper wire, and a 2 inch nail.  It works
> but I have to write a report about why and how it works. 
> So if you know anything about this, please e-mail me right away.
> 
> Thanks a lot,
> Ryan Vacca
> daves@ccinet.net
-----------------------------------------
J Wu
Email:jxw654@anu.edu.au
http://aerodec.anu.edu.au/~jxw654/h/ (Home Page)
http://aerodec.anu.edu.au/~jxw654/h/wyt.htm (Wanying Tea)
http://aerodec.anu.edu.au/~jxw654/h/book.htm (Cheap Physics Books)
-----------------------------------------
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Subject: Re: ABOLISH ACADEMIC TENURE
From: Dettol
Date: Tue, 21 Jan 1997 20:24:40 -1000
Troy Shinbrot wrote:
> 
> In article <32E44E4A.6BEF@gold.chem.hawaii.edu>, Dettol
>  wrote:
> 
> > DOES ACADEMIC TENURE HAVE ANY PLACE IN THE MODERN WORLD?
> >
> 
> 
> I am removing your copious cross-postings.
I'm putting them back.
> 
> Two remarks.
> 
> First, it is a shame that anything branded with the S- word is condemned
> in your philosophy.  S- in this case is Socialist, but it could be
> anything.  Rational analysis makes somewhat more sense than doctrinaire
> name-calling.
> 
> Second, I do not disagree in principle with some of what you have said,
> however there is one rather obvious and important point which you have
> overlooked.  I will speak as a scientist rather than an academic in
> another field, although the arguments apply just as well to other
> disciplines.
> 
> Let us imagine that you are a scientist, and you have an idea that
> requires more than 6 months to execute.  Into this category fits a great
> plurality, at least, of important work being carried out in any of the
> sciences.  How, without tenure, would you support yourself while this work
> is being done? 
The same way untenured faculty members currently support
themselves!!!????
The current system expects members to deliver the goods prior to being
given tenure.  Your scenario is paradoxical since if it was not possible
to do worthwile research without tenure then tenure could never be
obtained!
 Would you tell your dean, please sir or madam, I know I
> have produced nothing for the past 6, 12, 18, 24 months, and I know I have
> used umpteen gazillion units of various resources, but believe me it will
> pay off in another few years?  I think not. 
Well not if you phrase it like that anyway!!!  Reverse roles.  Would
give give anybody any money that said that?  Would you even give them
the time of day?
 I think under the scheme that
> you would promote that no work with a payoff beyond the next quarter would
> be carried out.  
Hello, is anyone home?  I don't recall advocating quarterly contracts. 
Five year contracts would be reasonable.  Do you mean economic payoff or
publishable payoff.  I think economic really only enters the equation if
the research is funded or co-funded by private enterprise.  Otherwise if
one were to use economic criteria we'd never do any basic research and
that would be a disaster.
If you mean publishable payoff I'm not aware of any journal that will
publish inside 3 months (well not the ones in my field anyway).
This is the system which has been adopted by US industry,
do you mean only looking toward the next quarter?
> and you may just notice that our cars, televisions, VCRs, radios,
> microwaves ovens, etc., etc., etc. are imported from countries with
> alternative systems.  Shall we import our science as well?
> 
> -Troy
Well I've noticed quite a few chryslers, fords and general motors cars
around but maybe Hawaii is different.  Yes the US imports and it also
exports.  Currently it imports more than it exports but I fail to see
what this has to do with academic accountability and tenure.
Science (other than corporate and military) does not belong to a
particular country by the way.
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Subject: Tonality/Emotiveness
From: Mark Hardie
Date: Tue, 21 Jan 1997 22:17:36 -0800
Isn't the real issue whether a particular tone produces an emotive
response from the listener?  In other words, there is nothing inherently
correct or incorrect about a particular tone as it relates to classical
music.  It is only important that the tone produce an emotive response
from the audience.
     What makes Sibelius' Finlandia great is not an objective tonality
standard; rather it is great because of the emotiveness produced by the
tonality.  Since classical music is an art rather than a science, is it
not pointless to look for some quasi-scientific measure of the music's
tonality.  It seems to me that this thread is importing science into
the realm of art.
     Let the tone move our hearts.
     Mark Charles Hardie
University of California,
Hastings College of the Law
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Subject: Re: ABOLISH ACADEMIC TENURE
From: Dettol
Date: Tue, 21 Jan 1997 20:26:52 -1000
Rebecca M. Chamberlin wrote:
> 
> Troy Shinbrot wrote:
> >
> > Let us imagine that you are a scientist, and you have an idea that
> > requires more than 6 months to execute.  Into this category fits a great
> > plurality, at least, of important work being carried out in any of the
> > sciences.  How, without tenure, would you support yourself while this work
> > is being done?  Would you tell your dean, please sir or madam, I know I
> > have produced nothing for the past 6, 12, 18, 24 months, and I know I have
> > used umpteen gazillion units of various resources, but believe me it will
> > pay off in another few years?  I think not.
> 
> You've produced literally *nothing* for 2 years?   Not even a partially
> completed experimental apparatus?  A failed test run?  Some theoretical
> evidence that your grandiose experiment will work?  What on earth are
> you reporting to your funding agency? (And why are they still sending
> you money?)  Have you noticed your graduate students getting a little
> testy?  Maybe even switching advisors?
> 
> If you've "produced nothing" and "used umpteen gazillion units of
> various resources" for 2 years, you sure as hell ought to be fired.  Now
> get to work!!!
> 
> Becky
Ditto
Mike
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Subject: Re: The "force" of gravity? Please explain.
From: kfischer@iglou.com (Ken Fischer)
Date: Wed, 22 Jan 1997 05:57:40 GMT
Dan Yertzell (Dan-Yertzell@worldnet.att.net) wrote:
: Ken Fischer  wrote in article ...
: > : Occam's Razor applies here.  
: > 
: >         Ok, great, Divergent Matter is the least complicated,
: > requiring nothing other than for quarks to not have enough
: > binding energy to maintain constant size.
: >         Newtonian gravitation requires magic to "pull" things
: > toward each other, and computers to specify how hard to pull.
: >         General Relativity requires spacetime to have some
: > unknown property that causes the inertial coordinate system
: > to have an affinity for massive objects. 
: But where are the computers to specify how fast each object must be
: expanding, so as to maintain the same relative sizes?  
        This is the underlying physics of matter, and the
relative sizes are the result of the acceleration-velocity
combination.    I would like to study this in relation to
the periodic table and density of the elements, but I'm
too busy answering questions. :-)
: Where does the magical "residual velocity" come from, and how is it
: *exactly* the right velocity to maintain the relative size (ie lead ball 
: inside a plastic ball)?
: TANSTAAFL.
       Why would velocity resulting from acceleration be magical,
At t_0 there was the Big Bang, t_0.5 was about ten minutes ago,
t_1 is now.    In about ten minutes, things will double in size,
but we will only observe the acceleration part and call it gravity.
: What about tidal forces in the Earth - Moon system.  How would a simple
: expansion explain that, with no "action at a distance", for lack of a
: better term?  
       All particles in moving bodies try to follow their own
geodesic, the higher the orbit, the slower they move, so there
is a natural relative motion between particles.
       But spacetime can not be Euclidean, and Mach should not
be mentioned, the geometry of geodesic motion is determined
by the kinematics of moving bodies.
: How is the moon "gravitationally locked", so the same side is
: always facing the earth?
       There is a large volume of denser matter within the
side of the Moon facing Earth.   I suppose this wasn't known
until spacecraft started orbiting the Moon.
       So this waters down the "gravitationally locked"
thing, it is really "gravity stabilized", a tidal effect.
       (Thanks for reminding me of this in relation to
Divergent Matter).
: And finally, can my waistline's residual velocity be slowed down, so it
: expands at the same rate as everything else?   :-)  Sorry, couldn't resist
: that one!
        Sure, if you eat less, exercise more. :-)
: You know, up until a year or maybe 18 months ago, I still had alot of the
: posts from the old FidoNet science echo, between you and the denizens of
: that echo.  They made for fascinating reading.  I wish I still had them.
: Dan
        I still have (probably all of) them, plus those from
a couple of other nets, GT and RIME.    I should make hard
copies to assure I don't lose them.    
        At the moment I am looking for my copy of Stephen
Hawking's 1971 Gravity Research Foundation $1,000 prize 
winning essay on black holes.
        I would like to buy any material published or
distributed by Gravity Research Foundation, I have just
the winning essays from 1949 to 1971.
        Incidentally, I entered the 1972 competition,
and was an also ran, and an honorable mention went to
a _Clifford Will_ that year. :-)
        There is a vast quantity of literature about
gravitation theory, but very little of it is available
anyplace.
Kenneth Edmund Fischer - Inventor of Stealth Shapes - U.S. Pat. 5,488,372 
Who's Who of American Inventors  Fourth Edition  1996-1997
Divergent Matter GUT of Gravitation http://www.iglou.com/members/kfischer 
Return to Top
Subject: Re: Does Apple (Apple) = Apple?
From: Rebecca Harris
Date: Wed, 22 Jan 1997 06:29:52 +0000
In article , Nick Sexton
 writes
>In article , Goddess
> writes
>>In article , Nick Sexton
>> writes
>>>In article <5as1hf$7jm@news.fsu.edu>, Jim Carr 
>>>writes
>>>>Rebecca Harris  writes
>>>>}STARGRINDER  writes
>>>>}>
>>>>}>get a life!
>>>>} 
>>>>} Hear Hear!
>>>>
>>>>Goddess  writes:
>>>>>
>>>>>Yeah! I don't see why they bother with these posts on here. Why don't they 
>>>post
>>>>>it on some maths chat group?
>>>>
>>>> To those of us reading the crosspost in sci.physics or sci.math, the 
>>>> concern is that completely misleading junk such as 
>>>>
>>>>: Comment: Note that atoms (atoms) = atoms
>>>>:
>>>>:       It seems that squaring an item (not a unit of
>>>>: measurement) equals the item.  What do you think?
>>>>
>>>> is being posted in k12 groups where it could confuse impressionable 
>>>> children.  If Kaufman was only talking to teachers, who should have 
>>>> the sense to ignore him, it would not be quite so bad. 
>>>>
>>>
>>>I'd just like to make a point. To whoever posts the educational stuff.
>>>Listen up.
>>>
>>>k12.chat.junior is a chat group. People talk and stuff. What really
>>>annoys people here is the educational stuff that gets posted. I don't
>>>think many people read it, anyway. (And those who do are probably on
>>>k12.ed.math anyway) So if you want to make us happy, then _please_ don't
>>>send stuff to this group. s'just a thought.
>>
>>Don't write 'it's just a thought'! Sweetie, nobody's goin' to listen to ya if 
>ya
>>say that! You gotta tell em out right. Just like that! It's not just a 
>thought,
>>cause everybodys thinkin' it, so SPEAK OUT!
>
>I just write "It's just a thought" so that it doesn't offend anyone if
>they disagree with it. Not that it works, or anything.
That's sooo thoughtful!!!
-- 
R33BOX
http://www.tharris.demon.co.uk/rebecca/
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Subject: Re: Tired light?
From: "Peter Diehr"
Date: 21 Jan 1997 17:49:55 GMT
Esa Sakkinen  wrote in article
<01bc07b9$d4627de0$c80e42c1@idesan.pp.fi>...
> Peter Diehr  wrote in article
> <01bc07b0$5f047f20$0963a098@ic.net.ic.net>...
> > Matter does not exist as points ... a photon can be scattered by
> > a close passage to an atom or molecule.   This scattering is the
> > cause of reflection and refraction, and the slowing of the
effective
> > speed of light through transparent media.
> 
> But, in fact, matter do exist as points at last as more or
> less possible points. I think that every individual 'particle'
exist 
> as a point and as whole universe. There can't be any space without
> points.
> 
But the points that correspond to quantum particles are not in
spacetime ...
they are in some Hilbert space (configuration space).  But I will
certainly
grant that the electron is point-like, when you conduct the correct
experiments.
> Interpretation of QED allows the idea I put forward.
> 
But the interactions between particles are not point-like ... that
also comes
from QED.  So I'll stick with the idea of scattering.  For some
further 
information, try Feynman's "QED: The Strange Theory of Light and
Matter".
Best Regards, Peter
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Subject: g=8pi*t...what is it?
From: archie t.
Date: 22 Jan 1997 06:45:10 GMT
Can someone explain the G=8pi*T means funcionally, 
and if it can give some light on, say, mercurys precession around the
 sun? (pun intended) Thank you in advance, the other archie.
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Subject: Re: This is impossible
From: drake.79@osu.edu (Macarthur Drake)
Date: 22 Jan 1997 06:40:19 GMT
>
>"Lighten up" from someone who said "I beg to differ with both of these
>ridiculus statments."  Go figure.
>
>-- 
>D.
>
>mentock@mindSpring.com
>http://www.mindspring.com/~mentock/index.htm
excuse me, but aren't you the one who thinks that 2000 years after 1/1/1 Ad 
is 1/1/2000 AD instead of the obvious answer 1/1/2001? perhaps you should 
'Go figure' and arrive at the correct conclusion.
Return to Top
Subject: Re: This is impossible
From: drake.79@osu.edu (Macarthur Drake)
Date: 22 Jan 1997 06:47:47 GMT
Excelent point. I never thought about that. No as far as the UFOs and Aliens 
that one is unprovable by scientific theories, currently at least
>
>Besides, don't knock confirming theories, even the ones that we're sure
>about.  That's how science works.
>
>--
Return to Top
Subject: Re: slingshot effect
From: "John DeHaven"
Date: 22 Jan 1997 06:47:20 GMT
Paul F. Dietz  wrote in article
<5c3ofn$649@nntp.interaccess.com>...
> "John DeHaven"  wrote:
> 
> >Not helpful yet. I don't see that the smaller ball would gain any net
speed
> >from any such collision. Indeed if I bounce a tennis ball off the earth,
it
> >never rebounds at a higher speed. Nor would any perfectly elastic ball
in
> >some lossless bounce.
> 
> It would not gain net speed *in the frame of the earth.*  It would in
> some other reference frame (for example, that of the sun.)
> 
> The usual example is: toss the tennis ball in front of an oncoming
> truck.  After the bounce it is travelling faster (w.r.t. you) than it
> was before the bounce.
> 
> For gravitational slingshots, substitute a planet for the truck and
> a spacecraft for the tennis ball.
Excellent! Settles that, then. How's my grok now:
You can't pull the slingshot trick any old whichaway, but only (to make a
profit) in such a way that it steals some of the orbital energy of the
massive body. This also means you can't do it with just any old relatively
massive body at any time, but only with one that is moving in such a way
that you can get a profit out of it. (If you want balls to go east faster,
bouncing them off of trucks going north isn't going to help you.)
The energetics are like if you bounce the ball off the front of the truck,
not only does the ball rebound more quickly, but the truck is slowed down
slightly. And if you bounce it off the rear of the truck, the ball rebounds
more slowly and you've pushed the truck along slightly. 
So in respect to (the frame of reference of) travel within the solar
system, you could pull the trick with planets or large moons, but not with
the sun itself. 
And as to extrasolar travel, we _already_ share the proper motion of the
sun in respect to some extrasolar frame of reference, but aliens from
starsystem X on their way to starsystem Y might find a slingshot around the
sun helpful for their trip if it's moving in the direction they want to go,
in their perspective.
This gives some feeling for the limits also: each slingshot trick drains
off a tad of orbital energy from the planet or moon. So keep doing that, or
do it with bigger spaceships, and eventually there would not be any more
useful (to you) orbital energy left. (And the orbit will have decayed,
probably badly enough for it to have spiraled into its primary.) Like if
you kept up a barrage of tennis balls long enough, you would stop the
truck, and you would stop it with fewer balls if you threw bowling balls
(at the same speed).
-- 
My header has been modified to attempt to foil junk-mail robots.
johnd@mozart.inet.co.th
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Subject: Re: This is impossible
From: R Mentock
Date: Wed, 22 Jan 1997 03:05:52 -0500
Macarthur Drake wrote:
> excuse me, but aren't you the one who thinks that 2000 years after 1/1/1 Ad
> is 1/1/2000 AD instead of the obvious answer 1/1/2001? perhaps you should
> 'Go figure' and arrive at the correct conclusion.
Nope, never said it, never thought it.  You've misinterpreted what I
did say.  
-- 
D.
mentock@mindSpring.com
http://www.mindspring.com/~mentock/index.htm
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Subject: Re: This is impossible
From: R Mentock
Date: Wed, 22 Jan 1997 03:06:59 -0500
Macarthur Drake wrote:
> 
> >He was wrong,
> >and they were right, but he was lucky that there was a previously
> >unknown (except to the Vikings) continent between Europe and Asia to
> >the east.
> >Evanston Illinois
> 
>         I am sorry, but you are wrong. The continent of America was
> enhabited by a variety of people, so of which produced very advanced
> civilization (Mayans for example) and presumably those people knew about the
> continent they live on. Sorry to nit pick you, but you did just discount a
> few million people who lived here BEFORE Columbus.
He mentioned this in his original post.
-- 
D.
mentock@mindSpring.com
http://www.mindspring.com/~mentock/index.htm
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Subject: Re: Mars Rock Crock!
From: Barry Adams
Date: Tue, 21 Jan 1997 15:44:17 +0000
»Word Warrior« wrote:
> >>*someone* wrote:
> >>* >>People properly nourished in clean surroundings won't
> >>* >>get cancer at all.
> >>Where does _this_ assertation come from?
> >It's an idea she has. She has provided no evidence in support.
> 
> Inaccurate/inapplicable; fallacious regardless.
> 
> >I
> >suspect it's a "New Age" thing.
> 
> Irrelevant.
> 
> Carcinogenic pollutants are a reality should
> you decide to familiarize yourself with some
> serious science on the subject.
  Carcinogenic pollutants aren`t the only causes of cancer.
Cancer can already exist in the Genome of the victim (e.g. 
oncoMouse (TM) ), or cancer can be caused by radiation
(ManMade or naturally occuring in cosmic rays or natural
radionuclides) or even by cell damage due to
impacts. (e.g. Testicular cancer can be caused by a kick in
the balls).
Apart from this Carcinogenic pollutants included superoxide
radials that are natural produced from the air. The incidents
of colon and stomach cancer have actually fallen in the last
fifty years due to the increased usage of antioxidant additives
in food (which destroy superoxide radials).
ManMade Mutagens/Carcinogens included Sulphur dioxide from
burning coal. (They form SO3- ions which reduce base nucleotides in
cells.) And Benzene (the molecule is flat so it can slip
through cell walls and slice up DNA like a knife) often found in
high octane lead free petrol.
For someone called `word warrior` you don`t tend to use many
words at a time. Short of ammunation are we?
Barry Adams
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Subject: Re: New Bad Astronomy Addition (1/7/97)
From: mmd@zuaxp0.star.ucl.ac.uk (Michael Dworetsky)
Date: Wed, 22 Jan 1997 10:11:11 GMT
In article  pcp2g@karma.astro.Virginia.EDU (Twisted STISter) writes:
>In article <32E026F6.F40@quadrant.net>, Bruce C. Fielder  wrote:
>>Purely psychological.  Anything that big looks larger when we have
>>something to compare it to.  When the sun or moon are close to the
>>horizen our eyes also take in the surronding scenery, and we notice just
>>how big these things are.
>
>As has been said here before, and as I outline on the Bad Astro page,
>this is incorrect. You can look at the Moon when it is high in the sky,
>*but still near foreground objects like trees*, and it still looks
>smaller than on the horizon. 
>
>>In the day, we look up to see them (the moon, at least!) and there is
>>nothing to compare them to.  The same type of thing happens with the
>>speed at which the sun moves; compare the speed of the sun across the
>>sky with how fast it rises or sets.
>
>Note that the light from the setting Sun or Moon is going through thicker
>and thicker parts of the atmosphere, which bends the light upwards. This
>effect means that you can actually see the Sun/Moon after it is physically below
>the horizon, because the light has been bent up to your eyes. This also means
>that it appears that the setting Sun/Moon slows down as it gets nearer the
>horizon. The distance it travels appears compressed, so the angular velocity
>slows down.
>-- 
>* Phil Plait, Pee Aytch Dee       pcp2g@virginia.edu 
>* My home page-- http://www.astro.virginia.edu/~pcp2g/home.html
>*      -->  Humor, supernovae, Bad Astronomy, Mad Science
>*           and my daughter Zoe.
There is an excellent article on the Moon Illusion in Quarterly Journal of
the Royal Astronomical Society, v27, pp205-211, 1986, by W. G. Rees.  His
conclusion, based on a comparison of all the common theories with
experiment, is that the illusion is caused by the perception of the
celestial vault (the sky) being much closer overhead than on the horizon.
Rather than our minds conceiving of the sky as a hemisphere, we seem
instinctively to regard it as a very flattened vault.  Thus, a Moon
overhead 'feels' twice as close as one seen near the horizon, so we
mentally assign it a smaller diameter.  This explains why it seems to make
no difference whether or not one has comparison objects in the line of
sight.  Refraction effects apparently play no role whatsoever.
-- 
Mike Dworetsky, Department of Physics  | Bismarck's law: The less people
& Astronomy, University College London | know about how sausages and laws
Gower Street, London WC1E 6BT  UK      | are made, the better they'll
   email: mmd@star.ucl.ac.uk           | sleep at night.
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Subject: Re: Utter Futility of Arguing With Creationites
From: bloore@h-plus-a.com (mARCO bLOORE)
Date: Tue, 21 Jan 1997 19:20:30 -0500
In article , ksjj@fast.net
(ksjj) wrote:
> I wouldn't expect creation to explain gelogical formations. The flood does
> a god job at that.
actually, the flood does a pretty mortal job of that.  things like
folded or diked sedimentary formations don't seem to fit the flood model.
************************************************************
Visit our top-rated children's site, Nikolai's Web Site, at:
http://www.nikolai.com/
mARCO bLOORE
Vice-President, Software Engineering
I. Hoffmann + associates inc.
Email:  bloore@h-plus-a.com    Web: http://www.h-plus-a.com/
************************************************************
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Subject: Re: Science Versus Ethical Truth.
From: Tani Akio Hosokawa
Date: Wed, 22 Jan 1997 00:17:08 -0800
On Tue, 21 Jan 1997, pharaoh chromium 93 wrote:
> > >  If this is the case, then
> > > an all-powerful being cannot exist without being paradoxical.  Absurd in
> > > fact.  
> Why absurd?
If you accept that an all-powerful being cannot exist without being
paradoxical (just for the sake of argument), then it is absurd to believe
in it, without throwing out the tenets of logic.  If you can accept that
logic is not universally applicable, then I invite you to do so, but you
must then accept that nothing you know right now has any value whatsoever,
because it has no basis in reality.  After all, if logic doesn't apply to
one, then it may not apply to another, or it may not apply to one thing
some of the time, and apply in other times.  Logic is something that
either must work or must not work...
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Subject: Re: how do gyroscopes work??
From: jac@ibms46.scri.fsu.edu (Jim Carr)
Date: 17 Jan 1997 22:25:18 GMT
mfarrington@alpha.ntu.ac.sg restates the problem:
>
>if you hold an axle with a spinning bicycle wheel at it's end
 OK, let's see if I have this right: I am holding an axle in front 
 of me, say at about waist level, pointing out away from my body. 
 The wheel is spinning on this axle so that L is also pointing 
 out away from my body (unspecified but important).  
 A good initial condition would be to have an assistant holding 
 the other end of the axle so we are both supporting the gyro 
 with zero net torque without having to work too hard at it. 
 (It takes strong wrists to provide the torque against gravity 
 with one hand.)  Now, if I am holding it up with just the tip 
 of my finger at the end of the axle (vertical force only), the 
 first demo is easy to do: have the assistant let go. 
 The weight of the gyro generates a torque about the point of 
 support, my hand.  The direction is given by rxF, which is 
 a vector pointing sideways so the change in L will be sideways. 
 Add delta-L to L to see the new direction of L in time delta-t; 
 this will be a horizontal precession (the gyro turns sideways 
 rather than tipping forward as you might expect, and as it would 
 if L was zero initially).  For the situation described above, 
 the natural rotation will be to the experimenter's "left", that 
 is, counterclockwise looking down from the ceiling. 
 The wheel does this without any help from the demonstrator, 
 who merely has to move either body or arms to keep out of 
 the way of the wheel.  So in this case, the demonstrator 
 can turn with the wheel (counterclockwise) about the support 
 point while providing an upward force of mg with the hand. 
>and turn on the spot clockwise, do you experience a different
>vertical force than if you turn counterclockwise??  
 What I do is irrelevant, what matters is what the wheel does. 
 To get the wheel to not turn at all would require that I supply 
 a *torque* (the upward F is the same as before) about the support 
 point that counters the torque from gravity.  Given the short 
 lever arm, this is hard to do (hence use of assistant above). 
 To get the wheel to go the other way would require that the 
 net torque be in the opposite direction (to the "right") which 
 means I need to double the torque gravity supplies.  
 The vertical force is the same; I have to twist the axle about 
 the support point of my hand.  The user might describe this as 
 an extra "force" since the muscles have to work hard to do it. 
 Now, if you thought (erroneously) that you need to twist the 
 axle sideways to make it turn, that torque would make the wheel 
 dip or rise rather than turn sideways and you probably would 
 perceive this as more or less "weight". 
>does the apparent weight of the bicycle wheel and axle change??  
 Not in the strict sense, but you would probably think that since 
 the effect of a large L is to make applied torgues do things a 
 bit differently than you expect.  
-- 
 James A. Carr        |  "The half of knowledge is knowing
    http://www.scri.fsu.edu/~jac/       |  where to find knowledge" - Anon. 
 Supercomputer Computations Res. Inst.  |  Motto over the entrance to Dodd 
 Florida State, Tallahassee FL 32306    |  Hall, former library at FSCW. 
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