Subject: Re: Whale strandings->earthquakes? Was: (Re: ...earthquake references)
From: gentryd@pipeline.com (Dennis Gentry)
Date: Mon, 13 Jan 1997 22:18:49 -0300
In article <5bd76q$7bn@miranda.gmrc.gecm.com>, richard.herring@gecm.com wrote:
>I suspect that what he meant to say was that the *fluctuations* in the field
>were 600 times their "normal" level. Whatever that is.
>Without an identifiable citation it's difficult to establish what he
>really said. What kind of fluctuations? Were they periodic, and if so,
>what was their period? Any correlation with increased solar activity?
>How often was this pattern of magnetic activity observed *without*
>earthquakes?
Good questions and I'll have to try and find the paper on it as I've
been quoting from an LA Times article.
From what I understand, this paper was presented at an AGU conference
in San Francisco in December of '95.
Al, saw your question and according to the article it was 600 times.
Regards,
Dennis
Subject: Re: Whale strandings->earthquakes? Was: (Re: ...earthquake references)
From: gentryd@pipeline.com (Dennis Gentry)
Date: Mon, 13 Jan 1997 22:19:21 -0300
In article <32DA0324.51AD@pacbell.net>, bilsmith@pacbell.net wrote:
>Dennis Gentry wrote:
>>
>> In article <32D7D7A4.3D30@pacbell.net>, bilsmith@pacbell.net wrote:
>
>> The burden of proving something false rests on the
>> person(s) not making the claim. How can the person
>> making the claim say his/her own theory is false?
>
>I didn't mention anything about falsifying a statement; you
>are introducing a new subject here. Your original statement
>suggests that every coincience may be related.
Exactly. It has to be proven that it isn't related.
>> BTW, the "clear means" that you used above is ambiguous
>
>I used the statement in the context that an assertion is
>arguable with information to back it up. I believe that
>is common usage.
And that is also exactly what I've been trying to say. Now
that were on the same wavelength. :-)
>> >There are elements in this reality that are NOT
>> >related. Blindly assuming that everything is related
>> >until proved otherwise is a long futile path to nowhere.
>>
>> I agree.
>That is not what you imply when you state "But it also
>doesn't mean that they aren't related." Seems like
>a contradiction to me.
No. Until a person delves into finding out whether
something correlates or not, it will never be know whether
it does or doesn't. But just because the data hasn't been
accumulated to back a proposal up doesn't mean that the
correlation isn't there.
>> My intent was to dispell any notion that just because....
>
>Sounds like nonsense to me. "Well, maybe it is related, but
>maybe it isn't. But just because it isn't means that maybe it is."
>What is left to dispell?
>>
>> And don't get me wrong, I'm NOT dispelling plate tectonics. Just
>> that all quakes aren't explained by that "theory".
>It is widely recognized by everyone except phychics that there is
>much to be learned about earthquake mechanisms. Plate tectonics
>is less than 25 years old (we have discussed this before!) as
>a popular model, and the learning curve is very steep. What
>are you complaining about, that we don't know enough yet? Sorry!
I wasn't complaining about not enough being known. But I am
trying to get acrossed that all *isn't* known. The way some
people out here talk, you'd think everything about everything
was known.
>> But, as I said above, the data should be collected to support
>> that claim.
>What claim?
Any claim that anybody makes.
But in this case it was an observation that a particular
person wanted to do a little research on.
Is their a problem with somebody making an observation, posting
a little about what they are thinking, and then asking where to
find the data in order to do a little research on it?
>> And if the data *is* collected to support the claim,
>> then its up to somebody else to disprove it.
>This sounds like sliding away from nonsense and toward
>a tautologically obvious path to nowhere.
Sorry, but I don't see it as that. I just don't believe that
people should stop looking for precursors because some people
think it won't go anywhere.
Science felt the same way about Alfred Wegener and about the
world not being round.
Let the data be collected and then see where we stand.
Regards,
Dennis
Subject: Re: The "force" of gravity? Please explain.
From: savainl@pacificnet.net (Louis Savain)
Date: Tue, 14 Jan 1997 07:48:46 GMT
In article <5bf5va$7k1@juliana.sprynet.com>, 745532603@compuserve.com
(Michael Ramsey) wrote:
>In article <32da9f3d.24890090@news.pacificnet.net>, savainl@pacificnet.net
>says...
>> [snip]
>>>How do you explain something moving along a space axis? If you have a
>>>calendar, how do you explain the flipping of pages, or the movement of
>>>the hands of a clock?
>>
>> It is just a change in position, that's all. Only the change is
>>real. Time is just the inverse of change, an abstract notion. To
>>insist that motion must be explained in terms of time is just as
>>absurd as insisting that the mass of an object must be explained in
>>terms of its inverse, 1/mass. As far as the intuitive notion of the
>>passage of time is concerned, it too, must be accompanied by motion,
>>as time cannot be divorced from motion. Check out the thread "Time
>>and its existance" where I explain this in more detail.
>
>Louis, let me try to make sure that I understand you. The Newtonian
>description of motion starts off with the concept of motion along a
>straight path. You measure a position x1 at time t1 and position x2 at
>time at t2. Time is measured by a clock, or by counting the beats in a
>musical instrument.
If time is by definition what clocks measure then we can stop right
here because I can assure you that clocks measure a lot more than
time. The changes taking place within the clock are part of a process
that involves d/v. Only d and v are observed. From that we obtain t.
For all practical purposes one can assume that d is constant. v on
the other hand depends on the clock's mechanism and the conversion of
potential energy into motive energy. Therefore, you are not using an
independent time to measure motion; you are merely comparing the
velocity of the internal mechanism of the clock with the velocity of
whatever moving body whose motion you're trying to measure.
> delta_x = x2 - x1 delta_t = t2 - t1
> v_avg = delta_x / delta_t
>
> v = lim as delta_t -> 0 = dx/dt
>
>Acceleration is the change in velocity with respect to time.
> a_avg = (v2 - v1) / (t2 - t1)
> a = lim as delta_t -> 0 = dv/dt
>
>The instantaneous acceleration is the derivative of the instantaneous
>velocity with respect to time:
> a = d(dx/dt)/dt
>
>You state "t = d/v." I assume that d=x2-x1. I assume that your t=t2-t1.
>I have no idea how you define velocity since you eschew v=dx/dt. This is
>why I say that your position is a mystery.
OK. I understand now why you see a mystery whereas I don't. I do
not eschew v=dx/dt at all. The problem has to do with the notion that
clocks measure time. Clocks, IMO, are velocity standards rather than
time standards. To say that they represent time is to ignore the
nature of clocks. the 'dt' in the equation v = dx/dt was not measured
independently from motion. It was obtained from motion, that of the
internal mechanism of the clock. 'dt' is mathematical trick that
makes it easy to calibrate the clock and easier to compare the two
motions. There was never an independent time involved. All along it
was *comparing motion with motion*.
Let us suppose for the sake of argument, that I had been in charge
of standards of measurement. I would not have created a special unit
of measurement for time (the second) since time is never observed
directly. Rather, I would have created a unit of measurement for
velocity, say a zeno, (I like to use 'zeno' as an example although
'knot' would do just fine). Since t = d/v, instead of measuring time
in 'seconds' or 'hours', I would measure it in 'meters per zeno' or
'miles per knot'. It sounds awkward but only because we are used to
the other way of doing things. Hopefully then, the confusion over
time would have come to an end. It is amazing what a simple choice of
units can do to color our perception of things. Nothing changed as
far as the math is concerned, only the psychological perception of
what is real and what is derived. Change is real. Time is derived
mathematically. Time cannot be divorced from change. It is the
inverse of change.
>Velocity associated with mass is not invariant under
>transformation from one inertial frame to another. Therefore physicist
>argue that velocity is not a fundamental quantity.
I don't understand that. If velocity varies under transformation,
so does time, as time is always obtained from velocity. This cannot
be denied. At any rate I don't see how invariance can have a bearing
on what is fundamental or not. Furthermore I am not saying that
motion is more fundamental than time. The two are inseparable. I am
saying that only motion exists and because time is a mere abstract
ratio, it cannot be divorced from motion and reified, i.e., given an
independent existence as is done in relativity.
>Now c is invariant under transformations from one inertial frame to another,
>but I do not see the speed of light entering into your discourse.
c has no bearing on the question of the illogic of time reification
that I can see.
>> [snip]
>> Well, I may have mistaken you for one of those "arrogant snot nosed
>>physicists" as Dr. Michio Kaku (of superstring fame) have described
>>them.
>
>People are people. We are tribal in how we deal with each other. To be
>successful in life you have to deal with cultural resistance to change.
>Bemoaning this fact is pointless; deal with it.
Good advice. I'll think about it.
>>>You have me the wrong way around. I am not trying to tell you
>>>how things work; rather I am trying to figure this stuff out myself.
>>
>> It seemed more like you had already accepted the party line and were
>>defending it at all costs.
>
>How did you come to that conclusion? When shopping for books (and theories)
>heed Daniel Webster's admonishment and don't be "like those who ask for what
>is new, instead of for what is good".
OK. In that case heed this. Time reification is bad.
>>> [snip]
>>>A motion picture film is a good model of what GR takes to be space-time.
>>>[snip]
>> This picture of reality as a historical map or record is indeed
>>powerful as an analysis tool. It is not however a model of reality.
>>It could not reflect reality because, as I've written elsewhere, it
>>reifies time into a dimension and *that* is illogical. Why? Because
>>as soon as you reify time into a physical dimension as required by the
>>model, you must give a logical explanation of how objects can move
>>along the reified time dimension. In order to move in time, objects
>>must obey the velocity equation v = t/t, a nonsensical equation that
>>says nothing about motion at all, let alone motion in time. So to
>>squarely contradict your conclusion above, the spacetime continuum is
>>a *very bad* model of reality. GR does not explain the flow of time
>>because the spacetime continuum model of GR forbids it. Can you
>>reconcile that with reality and still hold on to a reified time
>>dimension? I don't think so.
>
>Nothing wrong with that. Discovering nature's film projector is an
>exciting challenge. I can talk about film in the absence of knowing the
>details of the projector. GR says interesting things about how non-inertial
>motion can affect the speed of that projector. Interesting.
>
You cannot talk about a film projector if there are really no frames
on the film. The spacetime model requires the existence of an
infinity of frames all from a single predetermined and preplayed
script. That is not possible as seen above. In reality there is but
one frame, albeit a magical frame called the 'now', one which changes
in unexpected directions and twists. That makes for a much more
interesting movie.
GR is a *descriptive* theory which will be used as a gage with which
to measure other *explanatory* theories of gravity as they are
created. It does not give a local explanation for gravity, which is
needed to replace the Newtonian action at a distance as the
relativists have claimed for so long. It does not give an explanation
for anything. It is merely a more accurate mathematical theory than
its predecessor. GR is not *the* cause and effect theory which it has
been billed to be by overzealous fundamentalists. This undeserved
billing did much more harm than good in our search for a fundamental
understanding of reality. Especially in connection with the rampant
use of the spacetime "model" as an "accurate" model. Not.
Best regards,
Louis Savain
Subject: Re: circuit diagram for bathtub electrocution?
From: jvgorp@vnet3.vub.ac.be (Jurgen Van Gorp)
Date: Tue, 14 Jan 1997 08:59:49 +0100
In article <5as2o1$bk6@dfw-ixnews4.ix.netcom.com>, sppoulos@ix.netcom.com
(S.P.Poulos) wrote:
[...]
> So.......what really does happen when that radio or hair drier falls
> in? The notes here clearly indicate that it won't cause death. Will
> it cause anything? Tingling? A hearty zap? Nothing? Would love to
> know the answers to add this to my notes.
[...]
A few ciphers:
* Resistance of human body (approx. values)
- normal skin 2500 ohms
- wet skin 1000 ohms
- in water 500 ohms
Values are voltage dependent. These ones are given for 25 V
* Effects of current through the human body (approx. values)
- 1 mA : sense limit, you start feeling the current
- 10 mA : break limit, the muscles don`t listen to brain
commands anymore, you can`t loose contact,
you can`t move.
- 60 mA : heart fibrilation, your heart stops pumping,
it only vibrates at net frequency
- 3 Amps : most of the current now follows a path
through your skin instead of through the body.
Danger of dissection of the fat and burn
damage. (tasty, huh ? :o)
* Most dangerous paths : from hand to opposite foot (through
the heart) and from one hand to the other (through the lungs)
What would happen if an electrical device falls into your bath tube ? Of
course the currents are extremely difficult to calculate, so let`s just
say that only 10% to 30% of the current follows a path through the bathing
water. This is still enough for 22 mA to 66 mA through your body (Europe:
44 to 132 mA). Best scenario : you lay in the water, fried, one inch from
drowning, and your muscles slowly deteriorate.
Not my cup of tea.
Two side-remarks: 1) Fuses (main heat fuse of the house) most probably
won`t go off as the current in the water doesn`t exceed 10 Amps. 2) Very
likely the 30mA differential protection switch (obliged by law here in
Belgium) won`t go off either since most bathing tubes are not (or badly)
grounded to earth and there is no current path to ground.
--
Jurgen Van Gorp
e-mail : jvgorp@vnet3.vub.ac.be
Voice: +(32 2) 629 28 69
http://wwwtw.vub.ac.be/ond/elec
Subject: Re: How does an armored tank move?
From: erg@panix.com (Edward Green)
Date: 14 Jan 1997 03:10:34 -0500
Anthony Potts wrote:
>basically, I am saying this. If you disconnect the track just below the
>idler wheel, put it over your shoulder and walk forward exerting a force
>of 1000N, for two metres, the tank will be pulled forward only one metre,
>and will therefore be being pulled by a force of 2000N.
I think you mean the "below the _sprocket_ wheel", but continue.
>The reason this woks is that the track only moves for one half of the time
>(the other half, when it is in contact with the ground, it is stationary
>with respect to the ground).
>
>So, the driving wheel's circumference has a linear velocity twice that of
>the tank's velocity, and the force pulling the tank forward is therefore
>twice the force measured at the circumference of the driving wheel.
>
>
>You have a tension T in the tank tracks. You have tice this acting on the
>idler wheel, as it has two pieces of track pulling it, the bit below it,
>and the bit in fromnt of it.
Yes, agree with all analysis. We might point out though, that the
tension T in the track is pulling *back* on the sprocket wheel, so
the net force pushing the tank forward is in fact T, not 2T. Perhaps
you said this earlier. So actually there is no net mechanical
advantage; the force at the circumference of the sprocket wheel is
the force available to move the tank.
In your detach-the-track picture the man is now standing on the front
of the tank, and if he pulls the track with force N his shoes exert
an equal and opposite force on the tank body, canceling half the
force 2N developed at the idler wheel.
Again, I apologize if you said this already -- there is a hole in my
newsfeed. :-(
Subject: Re: question about motion/inertia
From: "A.J. Tolland"
Date: Mon, 13 Jan 1997 21:57:38 -0500
I'd say you should be asking a question about aerodynamics, not motion and
inertia.
Sorry. That was vague. (bad physicist!! WHACK!!!)
Let me try again.
Chances are good that you did not accelerate fast enough to knock
the keys off of the car.
That leaves the force the "wind" creates on the keys as it flows
over your car. I don't know the specifics of the problem but I would
guess that your car is shaped in such a way that the air doesn't blow very
hard over the car. BTW, what you've experienced is not terrifically
uncommon. I once drove fifteen miles, most of it at more than 55 mph,
with my daily paper on the room of my station wagon.
good day,
A.J. Tolland
"Do I LOOK like I know what I'm doing?"
ajt@wpi.edu
http://www.wpi.edu/~ajt
moderator: wpi.massacademy
Subject: Re: how do gyroscopes work??
From: lbsys@aol.com
Date: 14 Jan 1997 09:02:13 GMT
Im Artikel <5bee1b$9am$1@news.be.innet.net>, root@power7200.ping.be
(Operator) schreibt:
>>If you had infinitely rigid materials
>>constraining it to move only in a vertical plane, and infinitely
>>slippery lubricants to allow the joint to move despite having
>>gigantic torque act perpendicularly to it, then the Earth
>>would be turned by the gyro mounting in such a way that no
>>difference from a "normal" fall would be detectable. But in
>
[...]
>The only thing you need to destroy the "gyroscopic effect"
>is strong enough and finely tuned enough mechanics to
>counteract the small nutation motions of the gyro axis.
>Once that is accomplished, [...] the "constrained gyro"
>isn't a gyro anymore and the non-precessing motion
>is an acceptable solution of the equations of motion
...
I want my fish back ;-)
Patrick, you're in a big lab, aren't you? Why not give it a try? This is
my prediction: the constraint gyro will 'fall' just as slow as the non
constraint one (which does fall in the end, doesn't it). Whilst doing this
it will work its rotational energy up against friction (just like the
other one)....
BTW: Weren't you the one ranting against your boss, b/c he would argue
that his sink drain spins in direction of the Coriolis force - and not
accepting the reality of a real sink doing otherwise? Well, I constrained
a toy gyro - and it *seemed* to fall slower when spinning....
Cheerio
The most dangerous untruths are truths slightly deformed.
Lichtenberg, Sudelbuecher
__________________________________
Lorenz Borsche
Per the FCA: this eMail adress is not to
be added to any commercial mailing list.
Uncalled for eMail maybe treated as public.
Subject: Re: Astrology: statistically proven now!
From: lbsys@aol.com
Date: 14 Jan 1997 09:02:15 GMT
Im Artikel , trivedi@yukawa.uchicago.edu
(Anil Trivedi) schreibt:
>Interesting, but it really does not show anything more than
>people believe in astrology and may have married accordingly.
No. That would put much too much weight on astrological believe in the
public. It would suggest that some 7% of certain couples in love do NOT
marry, b/c they fear, that their starsign don't match - highly unlikely.
Much more likely, that they do not marry b/c they initially do not fall in
love.... but why?
>I think we will find the partners' racial, religous, financial,
>and educational backgrounds correlated even more strongly. :)
Yes indeed. And quite logically. But why shouldn't I marry my beloved one,
only b/c I was born in July, whereas I don't care at all about it (no
aberration from the statistical mean), b/c I was born in June?
Cheerio
The most dangerous untruths are truths slightly deformed.
Lichtenberg, Sudelbuecher
__________________________________
Lorenz Borsche
Per the FCA: this eMail adress is not to
be added to any commercial mailing list.
Uncalled for eMail maybe treated as public.
Subject: to keep an ice cube from melting
From: ben
Date: Mon, 13 Jan 1997 09:38:34 -0500
Hi people,
My name is Ben, and I have a friend in elementary school who
needs some help for a science project. Using materials available around
the home, she must keep a single regular-sized ice-cube from melting for
5 hours. Nothing commercial such as igloo ice packs, or iceboxes are
permitted.
She's tried stuff like saran wrap, styrofoam bowls and wood
chips, but the cube is completely melted by the end of the 5 hours.
If anyone has any tips or suggestions, they would be greatly
appreciated.
Thanks in advance :)
bensayo@ibm.net
Subject: Re: Rolling wheels and forces
From: lbsys@aol.com
Date: 14 Jan 1997 09:02:12 GMT
Im Artikel <19970113101100.FAA23593@ladder01.news.aol.com>, lbsys@aol.com
schreibt:
>Well, but what would Newtons bucket say to that :-?
Following up my own post..... I should rather sign off and go for a
holiday.....
Stirring my coffee in a train is the obvious answer, and the intuitive
result is, that it doesn't make a difference if the train is in the
station or moving at a constant speed.... :-(((
The most dangerous untruths are truths slightly deformed.
Lichtenberg, Sudelbuecher
__________________________________
Lorenz Borsche
Per the FCA: this eMail adress is not to
be added to any commercial mailing list.
Uncalled for eMail maybe treated as public.
Subject: Re: IS THERE A CASE FOR THE ELECTRIC CAR?
From: glhansen@copper.ucs.indiana.edu (Gregory Loren Hansen)
Date: 13 Jan 1997 15:52:02 GMT
In article <32D9CCCA.2212@vtiscan.com>,
Samuel Kass wrote:
>It seems like the only way an electric car can be viable is if, at
>"electricity stations", the entire battery is switched. Recharging
>doesn't seem to be getting significantly faster, and it's hard to
>imaging it happening in under 5 minutes. If, however, these stations
>had an entire rack of batteries recharging, and what you paid was the
>potential difference in energy between the battery you're turning in and
>the one that you're getting, plus some extra based on the difference in
>age between the two batteries, and overhead. Then the station starts
>charging the battery you traded to them, and you get a new one that
>should plug in easily.
One interesting idea I read is at the station, you change electrolytes.
Like some liquid chemical that gives you the electrical power in a battery
and breaks down with use.
Chrysler had a good idea. Fuel cells give you better energy density than
batteries, but storying the hydrogen is expensive and heavy. Chrysler is
developing a fuel cell that will break down gasoline into hydrogen and
waste products like water and carbon dioxide, and use that in a fuel cell.
And it's supposed to be twice as efficient per gallon than conventional
cars.
You could also use a hybrid gasoline-electric car. It runs on batteries
for as long as the batteries hold out, then an engine turns on to start
recharging the batteries. You only use gas if you go too far.
--
"But you can't let the package hide the pudding; evil is just
plain bad. You don't cotton to it. You've got to hit it in the nose
with the rolled-up newspaper of goodness. Bad Dog! BAD! DOG!"
- The Tick
Subject: Re: Hypothetical Universal Theory
From: robert.koss@mail.snet.net
Date: 14 Jan 1997 06:09:30 GMT
On 1997-01-13 whatever said:
>Well, off the top of my head, if the gravity acts on all matter,
>including light, any explosion will be contained in a closed system
>and the contraction will continue until all the matter is a at a
>single point. Sounds like this universe.
This is asuming the explosion doesn't give the matter escape velocity.
The current popular big-bang theory is not an explosion, but an expansion
of space-time..
..and for all we know, we are viewing it all backwards.
--: sqrt(x) = exp(log(x)/2)
Net-Tamer V 1.08 Beta - Test Drive
Subject: Re: More Mars Rock Crock!
From: lamontg@nospam.washington.edu
Date: 14 Jan 1997 05:50:18 GMT
Simon Read writes:
>fcrary@rintintin.Colorado.EDU (Frank Crary) wrote:
>>No. S/L-9 was a very unusual exception. It was captured by Jupiter,
>
>"Captured" means it stopped being in sun-orbit and started being in
>Jupiter-orbit. This simply didn't happen. Compare Shoemaker-Levy's
>approach speed with the speed of Jupiter's satellites relative to the
>collision. S-L 9 was travelling MUCH faster, hence couldn't have
>been in orbit round Jupiter.
>
>What may be confusing you is that S-L 9 orbited the sun and its orbit
>went past Jupiter a few times. Just because it went past Jupiter a
>few times doesn't mean it was in orbit round Juipter. It was in
>orbit round the sun, and it took many years before its orbit took it
>near Jupiter again. Its sun-orbit certainly went close enough to
>Jupiter from time to time that Jupiter's gravity could _disturb_ its
>orbit, but that's not the same at all as Jupiter _capturing_ it.
What's confusing me is the seminar I went afterwards to where I could swear
that computer simulations were suggesting that the comet got captured by
Jupiter appx. on the order of 100 or so years ago (undetermined due to chaotic
effects -- this was just a monte carlo statistical average). Of course, it
wasn't in anything resembling the orbit of a jovian satellite...
--
Lamont Granquist (lamontg at u dot washington dot edu) ->note spamfilter<-
"First consider a spherical chicken..." ICBM: 47 39'23"N 122 18'19"W
unsolicited commercial e-mail->contacting your ISP to remove your net.access
Subject: Re: Mars Rock Crock!
From: JohnAcadInt
Date: Tue, 14 Jan 1997 09:23:43 +0000
angus wrote:
.> > Science only documents how the 'world' works. (well, the Universe, or the
.> > atom, or whatever that particular branch of science studies).
.> Where I don't have my encyclopedia handy, this description of science
.> just dos'nt fit into the niche you seem to want to place it. Medical
.> doctors, and the science of medicene are refered to as science and often
.> "scientists. They document how medical science works and have a working
.> product that thet research also
There is always that feeling, isn't there, that now we have cured one thing or
another, or made something run faster or work better, we have done something
extra which ought to be called 'science'. It is, you know, a very dangerous idea.
Soon, you will find 'science' invoked in support of this or that 'desirable'
goal - as happened variously in Nazi Germany or Stalin's Russia. I doubt very
much whether you or I would wish to have the 'responsibility' that Hitler or
Stalin bore. Don't you see that? [This is where they opt for an 'objective'
solution. Ed.] 'Science' is only a method, I fear. You must look elsewhere
for your values. From where will you derive your values - if not from
'science'?
.> > ENGINEERING is the process of taking science and making something quicker
.> > or better.
.> Again, this just not seem quite right. Some of the places I traveled in
.> the service involved working near engineers, and I know one or two
.> locally. They spend a great deal of time and effort researching
.> theoretical fields related to engineering. Would'nt that be in a
.> scientists job resume???
Improving their understanding and technological skills. But why
should they bother? Think a little, please!
.> > As you hint, Engineering may have some moral dilemnas.
[ Ballocks! Ed.]
[ Engineering has no moral dilemmas! An engineer might! Ed.]
> Not really. Science and enginnering themselves are but just
> tools for us to use. The dilemnas might be in the application.
There are *no* dilemmas:
>A good example would be nuclear weapons. I deplore there
>idea and existance, but I do not hold the Los Almos
>scientists responsible for their existance. I hold the
>governments of the world responsible for their mis-use.
And what do you intend to do about it?
> > However, generally speaking Engineers are not totally responsible for what
> > they build; it's the politicians, the consumers, and the investors that
> > share quite a lot of the moral dilemna. Just as the Military never attacks
> > anyone; they do what the President and Congress tell them to do.
> I sorta half and half on this one. Scientists and engineers are'nt
> responsible for the results of their building and research, but I spent
> sufficent time with the military overseas to know that theres more
> shinanigans going on their at any given time that they should be made
> more accountable for their actions.
>
> > Pure Science itself, is simply understanding the mind of God in a more
> > concrete way.
>
> Really is'nt anything such as pure science, as theirs always an agenda
> for someone, and if God is the sum total of the natural world, then I
> could buy this last line.
>
> Regards
>
> Angus
> > == John ==
Apologies to s.a.a, but there seems to be some interest in that quarter!
Yrs evr
JohnM
Subject: Re: CROSSPOSTING (Was: Re: Mars Rock Crock!)
From: "David W. Knisely"
Date: Sun, 12 Jan 1997 19:59:03 -0800
Unless these posting have something to do with the hobby of amateur
astronomy, please remove sci.astro.amateur from your headings.
--
David W. Knisely, KA0CZC email: dk84538@navix.net
Prairie Astronomy Club, Inc. http://www.4w.com/pac/
Attend the 4th annual NEBRASKA STAR PARTY, AUGUST 2-9th, 1997
BABYLON 5: Our last best hope for QUALITY science fiction.
Subject: Re: Mars Rock Crock!
From: lamontg@nospam.washington.edu
Date: 14 Jan 1997 05:40:50 GMT
Anthony Potts writes:
>On 11 Jan 1997, Simon Read wrote:
>> Well, you may work for CERN and hence glow in the dark, but that isn't
>> everyone's experience.
>
>You don't actually understand what is done at CERN, do you?
You all sit around and sip tea all day in front of the beam dump, don't you?
--
Lamont Granquist (lamontg at u dot washington dot edu) ->note spamfilter<-
"First consider a spherical chicken..." ICBM: 47 39'23"N 122 18'19"W
unsolicited commercial e-mail->contacting your ISP to remove your net.access
Subject: Re: The "force" of gravity? Please explain.
From: schmelze@fermi.wias-berlin.de (Ilja Schmelzer)
Date: 14 Jan 1997 10:24:09 GMT
In article <32dc01bc.22852501@news.pacificnet.net> savainl@pacificnet.net (Louis Savain) writes:
> I'll pass on the "causality can't be proved" assertion as this is
>not germane to the discussion. What is important here is that GR
>physicists claim that certain things about gravity having to do with
>it being *caused* by the curvature of spacetime. They hold this as
>*the* explanation for gravity, meaning that there is no need to look
>elsewhere because they've already figured out how gravity works. The
>arrogance of a having little knowledge notwithstanding, this is plain
>hogwash.
At some moments it is reasonable to restrict yourself, because further
attempts to guess are only speculation without base. For example, I
propose that there is an ether, which probably has an atomic
structure, but I reject to develop a theory of this atomic structure.
Because I think there are hundreds of them and I have no reasons to
prefer one of them. GR places the restriction a little bit earlier,
and does not create models of the metric. That's all, no reason for
flames.
> One of those events is the constraining of moving body to a curved
>path. Logic tells me that, in order to constrain, one must have a
>constrainer and a constrainee. We know what the *constrainees* are,
>physical objects. Are you saying that the *constrainer* is the
>spacetime metric? If you are, then you and I disagree strongly.
>An abstract metric could not possibly have a constraining effect on
>matter, even if Mr. Einstein himself said it. That was my point in
>asking question 2.
Spacetime metric is only a name for a field g_ij(x) which not only
defines what we measure with clocks and rulers (the reason for the
name "metric") but also has a constraining effect on matter. What this
field, which replaces the Newtonian gravitational potential V(x),
really is, is not explained by general relativity, but this is no
reason for disagreement.
>> GR physicists define accelerated movement as the feeling of a force.
>>If you don't feel the force in your inertial frame, then the motion is
>>considered inertial.
> It seems that a lot of basic notions had to be redefined in order to
>fit the GR "explanation". What ever happened to the time tested and
>much simpler definition of acceleration being a velocity change in 3-D
>space?
It has happened that our distance measurements seem to be distorted,
we can measure only distorted relative distances. In such a world, we
have also no possibility to measure also absolute changes in velocity.
Unfortunate, but no way to avoid it.
And, please remark that my usage of different words to explain you
what happens does not mean that the usual words are wrong. Words have
a certain definition in the theory which may not coinside with the
common sense or philosophical usage of the same words. This may cause
misunderstandings if laymen try to understand them, but doesn't make
these statements wrong.
>>> GR physicists
>>>say that the curved spacetime inertial path (geodesic) is the only
>>>explanation for the known fact that the falling objects do not "feel"
>>>their own accelerations. Poppycock! What is wrong with the obvious
>>>and simple explanation that the gravitational force is applied to
>>>every part of a falling object equally? To the falling object this
>>>would be indistinguishable from inertial motion, even though the two
>>>are not at all equivalent. How's that for a super simple alternative
>>>to the equivalence principle?
The only problem is that you claim that there is a difference without
having a physical observation which is able to prove that there really
is a difference.
Of course, this is not a counterargument. But you also have no
counterargument to the positivistic position which claims "if we
cannot observe any difference, it makes no sense to distinguish the
two possibilities in the theory".
I think it is possible to detect that there is a difference using the
quantum principles. But, as long as we restrict ourself to classical
theory, there is no proof that the other, positivistic argumentation
is wrong.
> I agree that acceleration by itself is not force. But acceleration
>of a mass certainly involves force and that is too bad for the GR
>physicists because Sir Isaac Newton had already defined it as such
>with 'f = ma'.
It is too bad for your criticism that GR has not to bother about
Newton. It has to make the experimental predictions better than
Newton, that's all.
>Physics by redefinition to fit a flawed interpretation
>is not my cup of tea. Inertial path through a non-existent/abstract
>spacetime is not going to change that. GR's distorted definitions
>notwithstanding, the cause of gravity remains a mystery.
GR explains gravity by a tensor field g_ij(x) instead of a Newtonian
potential V(x) and obtains better agreement with experiments. The
cause of g_ij(x) remains unexplained, but every theory can explain
only in terms of other, unexplained notions.
> Having said that, let me add that I am not sure whether you are
>merely repeating the standard GR explanations or whether you are
>agreeing with them. If the latter, then we disagree. GR should be
>seen as a clever mathematical system for the prediction of motion. It
>is not a physical explanation of the causal mechanisms at play,
>something that GR experts have been teaching for more than a quarter
>of a century. Too bad. A correct explanation awaits a new theory.
If you criticize certain people for making metaphysical and
philosophical conclusions like a mystical "explanation of the causal
mechanisms", claiming they are consequences of GR, feel free to
criticize these people. If you criticize that people use notions for
explaining science to laymen which are misleading, like "spacetime", I
agree with you, explaining GR for laymen is not an easy job to do.
But this is not a problem of GR. Having developed an own, alternative
theory of gravity, I nonetheless defend GR from unjustified criticism.
If you name such misleading for laymen but correct in some certain
sense terms "wrong", I have to protest. GR - as a theory - is correct,
makes correct predictions.
Ilja
Subject: Re: THE WORLD OF CHEMISTRY; 2nd law of thermodynamics a fake
From: Malcolm Walters
Date: Tue, 14 Jan 1997 10:21:10 +0000
Archimedes Plutonium wrote:
>
> The 2nd law of thermodynamics needs readjusting. It is not true. And
> the analogy to put with it is to think of radioactivity.
>
> That in the case of most radioactivity, it is a decay process into a
> heavy element into lighter elements. This is the entropy part of the
> 2nd law of thermodynamics.
>
> However, not all is to a more disordered state. There are a few
> elements that are created not from radioactive decay, but from
> radioactive growth. One process that I can speak of which occurs
> naturally in nature is the case of a sample of uranium ore and that a
> few of those uranium atoms radioactively grow into a neptunium atom and
> some grow into plutonium.
>
> If the 2nd Law of Thermodynamics were correct then all
> radioactivities in the universe would be radioactive decay. And the
> universe should not have plutonium atoms in uranium ore samples.
>
> In fact, the scarce proportion of plutonium and neptunium found in a
> fabricated 100% uranium ore sample after x number of years is just the
> proportion of what ails the 2nd Law of Thermodynamics.
>
Surely you are misunderstanding the law, it says nothing about atomic
numbers. Ok there is some plutonium in uranium and so what. Surely the
presence of plutonium is disorder, entropy has increased. Order can be
produced but it leads to more disorder elsewhere. Solutions can settle,
this leads to order, things crystallise. However somewhere else in the
universe things have become more disordered, and it is this total that
you need to look at.
> And in the movie series THE WORLD OF CHEMISTRY showing Dr Don
> Shonwater (spelling) where he drops some dye into pure water and it
> mixes. But later shows tossing a salad, adding cucumbers and tomatoes
> etc and then tossing the salad. And Don makes the remark that those
> items in the tossed salad will never come back into its original state.
>
> However, if you limit your experiment, instead of the say 20 pieces
> of lettuce and 5 tomatoes and 6 cucumbers, etc. If instead you had but
> 1 tomato and 1 cucumber, then the original state comes back again with
> just a few tosses.
>
> So, what I am saying is that like in radioactive decay, the
> preponderant numbers are decay but a few are growth ( U to Np to Pu).
> And what makes the dye mix and unable to mix is that you have such a
> large number. And the same with the salad, only the salad is of such a
> smaller number. That when you bring the numbers down low, say one
> cucumber and one tomato that it is quite easy to get back to the
> original state.
>
Yes, statistical mechanics is all about this sort of think. 2 atoms yes
they can only be arranged in two ways 12 and 21. 3 objects could be done
as 123,132,213,231,312,321. A total of 6 or 3! ways. 1 mole can be
arranged in 6.022e23! ways. Thats a lot. Read a textbook on the subject,
disorder comes because it is more likely than order.
> I would think that there is a math quantization here. That if we
> consider a cucumber as a die face with a number and a piece of lettuce
> another die face and a tomato another face. Or each dye molecule as a
> die face. That we can say roll a number of die and relate that
> mathematically to a tossed salad. And so you can visualize that the
> chances of rolling the same die has a slim chance, and the die for the
> dye in pure water would be astronomically slim of recurring. However,
> as you make the numbers small-- one cucumber and one tomato tossed
> salad, that the chance of getting back to the original state (rolling
> the same die numbers) is highly likely.
>
> This is not the first time I have posted my misgivings of the 2nd
> law. In an Atom Totality theory, the 2nd law is a fakery because it
> cannot explain the 100% uranium block creating atoms of neptunium and
> plutonium. But the 2nd law is correct for the most part because it is a
> law that bespeaks of the process of radioactive decay, that most
> radioactivity is one of decay and not of growth. Here a gedanken
> experiment would suffice. If the entire universe were just a block of
> 100% pure uranium, and if the 2nd law were true, then there would not
> exist neptunium or plutonium atoms.
Subject: Re: Why do Black Holes Form at all?
From: hillman@math.washington.edu (Christopher Hillman)
Date: 14 Jan 1997 10:34:06 GMT
In article <32DB0B90.3A6F@quadrant.net>,
"Bruce C. Fielder" writes:
|> If the gravitation of a black hole is such that anything falling into a
|> black hole will have its "time" slowed the closer it comes to the event
|> horizon, how does the thing form in the first place? Surely as the
|> original mass contracts, it should slow (from our point of view) until
|> the original mass remains "waiting" (sorry about all the quotation
|> marks) at the event horizon?
|>
|> As far as I can see, the same should hold true with the mass inside the
|> (soon to be) event horizon; the acceleration and gravity increases and
|> slows the time to infinity. So how does the thing ever form in our
|> universe?
The "picture" of a black hole you probably have in mind (really a sort of
map of a particular closed space-time, in the same sense that a Mercator
projection is a particular map of a certain curved surface) are the
Scharwzchild coordinates, in which the "event" horizon appears as
a cylindrical coordinate singularity. Geometrically, this cylinder
(in the map) is really a circle (i.e. a two-sphere). There are other
coordinate systems in which this coordinate singularity is removed.
The best is a conformal map (preserving small shapes, like the Mercator
projection does for the surface of the earth) called the Kruskal-Szekeres
coordinates.
It is true that an exterior observer (usually assumed to be stationary
wrt to the black hole) observes nothing of the history of a particle
after it passes through the event horizon. Moreover, as a particle
approaches the horizon, signals from it back to more distant observers
are extremely redshifted and also fade in intensity (exponentially in the
time of a distant observer, in fact, contrary to the impression left
by the Schwarzchild coordinates that a distant observer will observe
particles "hanging" suspended near the event horizon.
Nonetheless, a particle falling into the BH (or the matter of the star
itself as the hole is being formed) experiences nothing strange as it passes
through the event horizon. The event horizon is an artificial mental construction
(like the international date line) which has a GLOBAL significance (this is
the point of no return) but no LOCAL (physical) meaning. Indeed, by
a remarkable coincidence, it turns out that you can obtain the correct
experience according to gtr by a simple Newtonian analysis. Specifically:
Consider two particles falling straight into a gravitational source of mass M.
Suppose one is at radius R and the other at radius R+L (L small wrt R).
Then they accelerate apart relative to one another as
-GM/R^2 + GM/(R+L)^2 ~ 2GML/R^3
(where we expand in a power series in L, neglecting all but the first order term).
If we have two particles both at radius R and seperated tangentially by L,
they accelerate toward one another as
-GM/R^2 (L/R) = -GML/R^3
(by similar triangles). That is, the curvature coefficients are 2GM/R^3 radially
and -GM/R^2 tangentially. Someone falling into a black hole is therefore
compressed tangentially and expanded radially by the force of gravity, this effect
increasing smoothly as R^(-3) right through the event horizon and down to
the true singularity at R=0.
It is not obvious but true that these Newtonian values are in fact correct
according to standard gtr for a non-rotating non-charged black hole.
I have modeled this discussion on the first few pages of the beautiful
book Gravitation, by Misner, Thorne, and Wheeler, Freeman 1970, which
also contains a thorough discussion of many coordinate systems for
black holes including the Kruskal-Szekeres coordinates, and various
techniques for calculating the curvatures and verifying that the values
given here are correct.
Another way to visualize the situation is to consider a sphere of particles
"at infinity". They begin to fall slowly into the hole, carving a three
dimensional surface out in the four dimensional space-time as they do so.
You can readily determine the intrinsic geometry of this section using
methods dicussed in MTW and then it turns out you can embedd this "world-surface"
as a sort of half-football in R^4. Again, the event horizon is simply one of many
spherical "latitude surfaces" on this football, and is not distinguished in any
way from its brethern. Incidently, such "world surfaces" form an entire family
of surfaces carving up the space time. There is a family of "orthogonal" surfaces
defined in the same way that potential curves determine streamlines in the
conformal mapping method of solving hydrodynamical flow problems. These
orthogonal surfaces are flat R^3 planes, flat right down to the singularity!
That is, the Scharzchild universe is a sort of four dimensonal "ruled surface".
A more familiar example of a (two dimensional) ruled surface is obtained by
taking a twisting curve in R^3 and considering the surface carved out by its
tangents. Typically this surface has a sharp cusp along the curve itself;
the true singularity as the center of a black hole arises geometrically
in an analogous fashion.
Hope this helps!
Chris Hillman
Subject: Re: Basic Particles/Waves again!
From: John Murphy
Date: Wed, 15 Jan 1997 00:01:37 +1200
Jim Carr wrote:
>
> Mike Norris wrote:
> }
> } THE TWO SLIT EXPERIMENT.
> }....
> } If this is followed through it gives a good explanation of constructive and
> } destructive interference fringes in the two slit experiment.
>
> John Murphy writes:
> >
> >Who says that the patterns are in fact due to the process of
> >interference.
>
> That was the acceptable explanation for a number of optical effects
> for several centuries. It is sufficiently straightforward that many
> college freshmen can carry out the derivation.
Nobody, not even a college freshman can reconcile the corpuscular nature
of light with the process of interference. There is no representation
for the key processes in any of the mathematics.
I say, with the same college freshman maths, I can demonstrate how
localised
particles can scatter into exactly the pattern that occurs. The model
makes
use of the fact that matter is a quantum structure and that you can
treat
the slits as such. You find, that like an atom, the slit screen can only
exchange momenta/energies with a particular spectrum and that the
spectrum
you get exactly matches the one you see superimposed on the particle
beam.
> >It may look that way, but remeber it also looks as though the sun goes
> >around the earth.
>
> A simple transformation suffices to connect those reference frames.
> Alternative explanations of diffraction patterns would be interesting
> to see worked out. I have not seen one.
Go and look at my Web-Site
http://www.murphy.gen.nz/murphy/sham_idx.htm
It even details a commonly used signal processing device that works on
the same principles I describe.
> } This gives a good explanation of electron diffraction (including two slit)
> } in both wave and particle terms. It explains the different energy
> } disribution produced when one or two slits are used ...
>
> >I say it doesn't give a "good account" as such. Rather, its an absurd
> >conclusion that you are forced to consider if you accept th'at the
> >process that gives rise to the observed pattern is interference.
>
> There is nothing absurd about the pattern on a photographic plate.
I agree, it exactly fits what I describe.
> You are not forced to accept the existence of an image on the plate
> by the theory; the theory predicted the observed fact that the pattern
> produced by electrons and x-rays are the same under given conditions.
What theory, the theory of interference is a facile explanation that
does
not have a full representation in the mathematics of quantum theory.
I've searched Hilbert space high and low and I've never seen any of the
elements of interference.
On the other hand, the patterns do also just exactly fit
the ray-optic scattering that would be obtained from a spectrum that
can be calculated from a simple Fourier transform of the slit layout.
> >Interference presumes that the photons actively posess "wave" properties
> >that actively participate in the interaction with the "passive" slits.
> >
> >In reality, the Slits are a "sea" of quantum excitations. Matter is
> >largely empty space filled with quantum excitations.
>
> This transfers the wave property from the particle to its interaction
> with space, and the non-local effects of the wave function to the
> non-local knowledge this space has about the presence of slits.
Rubbish, Mr Planck's law is quite explicit about the states of motion
present in matter, they are characterised by being periodic with a
frequency
energy/momentum relationship. These are experimenatlly verified - _your_
wave function is not even an object in space-time. It is an infinite
dimensioned
Hilbert space representation that all texts say is isomorphic with sets
of statistical patterns.
All I am saying is that when you consider matter to be constructed of
such
excitations and do some simple sums on their spectra then you find that
they must exhange momenta in a way that matches the observed results.
> It sounds to me like space now has the role of the wavefunction,
> although it is not clear how it treats many-body problems such
> as scattering.
No, I'm saying that the exact same Hilbert space model can be
successfully used to predict a spectrum that occurs in a real
population. Furthermore, this model allows you so set aside
the mystical features of the interference model.
You on the other hand, champion an view in which the elements:
- particles passing through both slits,
- waves occupying all space available to the particle,
- the sudden transformation of the particle to a localised impulse
> It seems easier to me to associate those attributes
> with each particle as appropriate, as is done in classical mechanics.
Why do you think that that would be easier? So that you can keep your
blinkers on?
John
Schroedinger's cat leave you half-dead,
Do you go limp at the thought of conciousness-induced collapse.
Then try "Is Wave/Particle Duality a Sham?"
http://www.murphy.gen.nz/murphy/sham_idx.htm
Want a hint of some EPR magic - coming soon
http://www.murphy.gen.nz/murphy/epr_idx.htm
Subject: Re: PH.D.s are useless
From: David Sepkoski
Date: Tue, 14 Jan 1997 02:07:14 -0800
April wrote:
[snip]
> A person who seeks to aquire a PH.D. has that motivation. For people
> who aspire wealth, a PH.D. is not necessary. One has to have the
> motivation to take big risks in starting their own business. Most
> people I know that are on their second majors in college are blindly
> following the path laid before them by their parents'. Go to college,
> get a PH.D. and you will be successful!! But those who aspire to be
> self employed have the guts to risk, suffer failure, and end up
> successful enough to hire degree holders to be their lawyers,
> accountants, financial advisers......get the picture??
Why do you assume that earning money is the be-all and end-all of human
existence? Sure, making a lot of money has its compensations, but not
everyone cares about that kind of thing. And believe me, most people
who get PhDs aren't out for the money. I think that you are confusing a
JD or an MD (which really isn't the same thing) with a doctorate. You
can get rich and hire all the lawyers you want, but good luck trying to
find a physicist or a historian to keep around the house. And as for
your comment that
>it was infinitly easier to go to college and get good grades, But it did
> not compare to the stress, risk, and enormous amount of motiviation
> required to start a small business!
I don't think you have any idea what getting a PhD is all about. I've
read a lot of posts that seem to indicate that getting a doctorate is a
simple matter of studying hard or memorizing a lot of useless facts.
Its not. It is about intellectual creativity, hard work and as much
stress as you'll find in any other occupation. It ain't about pulling a
B+ average in a bunch of lecture courses in college. So before YOU go
assuming a bunch of things that YOU aren't informed about, I urge you to
heed your own advice. I'd like to see YOU try it, ace.
Subject: Re: Mars Rock Crock!
From: angus
Date: Mon, 13 Jan 1997 18:20:49 -0800
Anthony Potts wrote:
>
> On Fri, 10 Jan 1997, >>>--->Word Warrior<---<<< wrote:
>
> >
> > Sunlight is the source of all life on the planet.
> >
> Idiotically wrong. There are creatures who live in deep sea vents whose
> energy and nutrients are not dependent on sunlight in any way shape or
> form.
How bout partially wrong. This Kid got most of it right as life is
dependent on the existance of the sun for life. Even the sea vent life.
Heat from sunlight keeps the inversion layers in the ocean going in
their cycle.
Besides, take the sun away and see how long any life lasts on this
planet.
You picked one example of a type of life that evolved by adapting to the
heat and nutrients being pumped out through volcanic vents. Even then,
solar inversion helps these plants also by circulaing the marine layers.
I suggest that you stay away from biology, it obviously isn't your
strong
> suit.
>
> Anthony Potts
>
> CERN, Geneva
You pal, have no class. He has the right idea, but missed one of the few
adaptations that exist, and you act like a total jerk.
Angus
Subject: Re: Hypothetical Universal Theory regarding Big Bang, gravity, and matter.
From: Ralf Kleineisel
Date: Tue, 14 Jan 1997 12:13:08 +0100
nebula@spacelab.net wrote:
>
> � Due to gravity all matter in the universe will eventually join together
> forming one enormous amount of matter in the universe, thus a very strong
> gravitational pull capable of attracting every mass significant
> particles, light as well.
>
> � Entering Assumption: A reaction happens eventually when all
> matter in the universe is collected and contracted together.
>
> � Entering Sub-assumption: The reaction is an explosion.
>
>
> Theory: Due to enormous explosion, all matter is being distributed
> all over the universe once again causing another big bang.
>
> -----
> I would like some comments on this, bad or good, whether it makes sense
> to you or not. I would like to have discussion on this subject.
>
> Thank you very much.
>
> All e-mails are welcome, if you prefer.
>
> {Sorry for reposting this in alt.sci.physics.new-theories, I simply
> wanted to correct a few text errors.}
The Big Bang wasn't an explosion IN the universe, it was the explosion
OF the
universe. Before the Big Bang, there even wasn't space itself. Because
of the
BB the space itself expands, not the matter within a static space.
Subject: The Universe, a billiard game?
From: Jan Pavek
Date: Tue, 14 Jan 1997 12:35:42 +0100
Why does the Universe work the way we know it? Don't know if that's a
common theory, but it's nice to think about it. The Universe could work
like the balls in a billiard game. One ball hits another one and you
never really know where it will hit the next one. If there was a
beginning of Universe's being it was caused by something like a billiard
ball. When it hit the part where our Universe started, it produced
randomly the Universe with its physical laws and all that things we
know. Therefore there can be anything we ever thought about and more.
All happenings in our Universe are only caused by hitting billiard
balls. You don't know where it really goes and you can't really change
it. Your action is nothing more than a hit of a ball which was hit by
another ball...
Jan
---
I know I'm not a brainy one, but I'm working on it!
I only want to understand!
Jan Pavek \|\*(:-)
mailto:p7003ke@hpmail.lrz-muenchen.de
surfto: http://www.lrz-muenchen.de/~gravilabs
"Why don't we see it as it is? A flower, a tree, a mountain, a bee ..."
"Do you realize the power of the dream?..."
Subject: Re: A case against nuclear energy?
From: zcbag@cnfd.pgh.wec.com (B. Alan Guthrie)
Date: 13 Jan 1997 18:13:48 GMT
In article <5ar8ch$fsi@valhalla.comshare.com>,
Mike Pelletier wrote:
>In article <5a9uga$ia4@news.fsu.edu>, Jim Carr wrote:
>>
>> It was refined, and of course it was not *in* a critical mass or it would
>> no longer be there. Forming it into the proper shape, and assembling
>> same, is the only 'problem' one must solve. But the main issue has to
>> do with the cavalier way this stuff was handled at Rocky Flats.
>
>I was under the impression that plutonium at its normal density could not
>be assembled into a critical mass, which is why they used the implosion
>design to increase the density of the plutonium core to force it to a
>higher, supercritical density.
>
>Is this incorrect?
Yes, it is incorrect. Of course, you can get a critical mass from
plutonium at its normal density (if you think, you will probably
recall a homework problem in reactor physics in which you calculated
the mass). One cannot make a weapon with plutonium at its normal
density, which is what you really meant to say, I think.
--
B. Alan Guthrie, III | When the going gets tough,
| the tough hide under the table.
alan.guthrie@cnfd.pgh.wec.com |
| E. Blackadder
Subject: Re: to keep an ice cube from melting
From: Dave Monroe
Date: Tue, 14 Jan 1997 08:02:56 -0500
ben wrote:
>
> Hi people,
>
> My name is Ben, and I have a friend in elementary school who
> needs some help for a science project. Using materials available around
> the home, she must keep a single regular-sized ice-cube from melting for
> 5 hours. Nothing commercial such as igloo ice packs, or iceboxes are
> permitted.
> She's tried stuff like saran wrap, styrofoam bowls and wood
> chips, but the cube is completely melted by the end of the 5 hours.
> If anyone has any tips or suggestions, they would be greatly
> appreciated.
>
> Thanks in advance :)
> bensayo@ibm.net
I remember Union Carbide used to use layers of foil and paper to keep
liquid nitrogen cold for long-haul rail transport.
Try 5 pieces of aluminum foil and 5 pieces of brown craft paper in
alternating layers.
Good luck.
--
David S. Monroe David.Monroe@cdc.com
Software Engineer
Control Data Systems
2970 Presidential Drive, Suite 200
Fairborn, Ohio 45324
(937) 427-6385
Subject: Re: faster than light travel
From: Ewen Charlton
Date: Tue, 14 Jan 1997 12:26:15 +0000
Dean Povey wrote:
>
> Jos Dingjan writes:
>
> >I vaguely remember seeing some program about this on the tube. They sent
> >Mozarts x'th FTL (or so they claimed). It had a certain vinyl-quality
> >(nothing like that crisp CD sound) but you could still recognise it. Now
> >if I only could remember the program...
>
> >HTH, Jos
>
> A discussion of the "tunnelling" phenomena which gives rise to this FTL
> phenomena is given at http://lal.cs.byu.edu/ketav/issue_3.2/Lumin/lumin.html.
>
> Dean.
I just looked at the above site, and in it it is argued that the bar of
Mozart was only able to go FTL because it was a smoothly varying pulse.
Unfortunately I didn't see the program, and didn't hear the quality of
the transmission, but if the bar of Mozart had had some speech
overdubbed, would this speech have been recognisable after transmission?
And if so, wouldn't this constitute a 'signal'?
Ewen
