PSN-L Email List Message

Subject: ageing, baking, and creep
From: Randall Peters PETERS_RD@..........
Date: Fri, 28 Sep 2012 13:03:00 -0400


This message has nearly 'grown without bounds', and so you may want to go s=
traight to the last three paragraphs (if you have any interest whatsoever).

Brett,     I am glad to hear of how you bake the spring to hasten stability=
..  In some of my  experiments performed in vacuum it was necessary to bake =
the entire chamber, as is common practice by those who do high vacuum studi=
es.  Otherwise, diffusion pumping that follows mechanical pumping will neve=
r allow one to attain the pressures being sought.   These real world frustr=
ations, that are well known to members of 'vacuum societies', point vividly=
 to the fact that the physics is even more complicated than just defects/di=
slocations in an otherwise perfect material that we envision (erroneously) =
as existing in no other state than that which we call 'solid'.  In other wo=
rds, what has been the focus of our discussion (a spring) is also influence=
d at the 'defect' level even by the gases of the atmosphere in which it ope=
rates!  (And incidentally, the surface of a solid is the 'quintessential' d=
efect that cannot be avoided, since the 'perfect' solid must be of infinite=
 extent.)
         If one altogether doubts that gases don't probably always play som=
e role, at least at some level (perhaps insignificant, but how can such a c=
laim be made without experimental proof) consider an experiment involving a=
 shape memory alloy that I performed several years ago, which produced the =
article titled "Study of friction at the mesoscale using Nitinol shape memo=
ry alloy" http://arxiv.org/html/physics/0308077
You will see from this work what is indisputable evidence that gases can si=
gnificantly influence mechanical properties in ways that are not commonly k=
nown.  The quality factor differences for the oscillations that are themsel=
ves of different Q, according to whether the material is in the martensitic=
 phase or the austenitic phase-are responsible for a profound 'declaration'=
 about the importance of defects/dislocations to a spring type oscillator. =
 And the manner in which significant phase noise was found to be present, a=
long with 'Brownian motion', means that the low-level fluctuations are exce=
edingly complicated and never completely reproducible.  I have facetiously =
said to colleagues through the years:  "Guess I will have to report my find=
ings in the journal of non-reproducible results".   If such a journal actua=
lly exists, no bonafide scientist would go read anything published there, b=
ecause the very 'heart and soul' of science is reproducibility   Consequent=
ly, most of my research publications have been 'open access'; and the Googl=
e search engine seems to have become my greatest ally.  I was denied promot=
ion years ago in Texas and the dean who sealed that decision wrote in her l=
etter, "I hope Professor Peters will eventually be able to say I told you s=
o"--concerning my studies of the mesodynamics of mechanical systems.   Just=
 as I was retiring this past spring, one of the most significant publicatio=
ns of my career was about to be published in Physical Review E (highly este=
emed refereed journal that is the antithesis of open access publishing).  L=
ess than a year before this, two distinguished French (nonlinear) math/phys=
ics experts had found one of my papers dealing with catastrophes.  I had pu=
blished that article only in one place (Mercer physics personal homepage) b=
elieving (based on painful experiences with referees) that it had about a '=
snow ball's  chance in hell' of ever getting published 'conventionally'.  F=
ollowing the request by my later-to-be co-authors, I performed an experimen=
t that resulted in our article "Prediction of catastrophes-an experimental =
model".  As it was coming together I made a claim to colleagues that proved=
 to be 'right on target figuratively'-"there's not a referee in hell who wi=
ll dare reject this paper, because of the outstanding reputation of my co-a=
uthors".  (You can readily read the abstract of our article by simply typin=
g 'prediction of catastrophes' into Google without the tick marks of a lite=
ral search. You should be able also to easily with Google find the complete=
 preliminary article that was open source published on arxiv.)  I mention t=
his to you list-serve readers for another reason-which if it should ever pr=
ove to be profound-remains yet (only after a long time, if ever) to be seen=
..  If you will look at the following paper:  http://physics.mercer.edu/hpag=
e/accelerometer/accelerometer.html
You will see what is an event that preceded an earthquake.  It is of the ty=
pe that I have seen (in a related context, also by Michael Phillips in Aust=
ralia; who calls one type the "Randall effect') quite frequently as tantali=
zing evidence for 'precursors' to earthquakes.  At this point in time, anyb=
ody making a claim for the possibility of meaningful 'early warning predict=
ors' of an earthquake (that could save lives) is viewed as either a (i) mys=
tical quack, or an (ii) ignoramus masquerading as a scientist.  The basis f=
or such a position is not without justification, since true earthquake pred=
iction is  a 'holy grail' type of quest, afflicted with the greatest of sci=
entific challenges.  I personally believe, however, that professional seism=
ologists have not been 'asking the right questions' relative to the matter.=
  Just like Nobel Laureate Charles Townes has said the same thing about tho=
se who are life science specialists.  It is easy to 'fold one's hands' and =
say "the problem will never be solved".   Certainly more physics has been b=
rought meaningfully into cutting edge biology of late, and the same is sore=
ly needed in seismology.  I have had little success in my efforts to relate=
 meaningfully with professional seismologists, which is part of my reason f=
or coming to your amateur world several years ago.  One of my 'successes' w=
ith the  pro's was nevertheless realized a few years ago with my BSSA publi=
cation titled "Tutorial on gravitational pendulum theory applied to seismic=
 sensing of translation and rotation".  This article would never have happe=
ned had I not met the great John Lahr, who like myself had a burning passio=
n for science education.   And that passion of his 'spilled naturally' into=
 your world, which is the place where I first learned of John and his legac=
y.  I was greatly pleased to learn how the genesis of his passion was undou=
btedly part of his earliest university degree (B.S. in Physics from Renssel=
aer in 1966).
      The way my tutorial materialized is an example of  how the butterfly =
effect of Ed Lorenz suggests meaningful extrapolation beyond his original s=
tatement ("Can a butterfly flap its wings in Brazil and cause a tornado in =
Texas", article presented in the early '60's at a Washington D.C. meteorolo=
gy conference-about his serendipitous discovery of the 'sensitive dependenc=
e on initial conditions that is the foundational part of chaos).  In the br=
oader social sense, I see it (involving systems even more complex than atmo=
spheric convection) to describe how "little events of life can unexpectedly=
 take on unforeseeable monumental proportions".  Early after my use of the =
first fully differential capacitive sensors I became enamored with the pend=
ulum, one of the oldest instruments of science.  Few people know the full e=
xtent to which the gravitational pendulum in its 'simplest' form has impact=
ed our world.  Even the foundation theories of fluid mechanics (Navier-Stok=
es equations) derive from studies of the pendulum that were performed by th=
e legendary George Gabriel Stokes.  Those in turn influenced even the world=
 of meteorology where Lorenz is considered the father of chaos theory.  Sto=
kes famous-to-physicists theorem, that derived from his pendulum studies, d=
escribes the manner in which only small rain droplets in clouds have a smal=
l enough Reynolds number to remain part of the cloud, while under the influ=
ence of the earth's field of gravity type (little g).  In his paper generat=
ed in 1850  ("On the effect of the internal friction of fluids on the motio=
n of pendulums") Stokes rightly predicted that his conclusions would have s=
ignificant impact on the world of meteorology.
         Another of my experiences involving butterfly effects of social ty=
pe (that involved the sequential outworking of more than just one)  'revolv=
ed' around the article that I wrote for the 10th edition of the McGraw Hill=
 Encyclopedia of Science and Technology.  My article accompanies one that w=
as written by Lorenz before his death, and another piece written by a physi=
cs theorist who was at Georgia Tech (quantum mechanics expert named Joseph =
Ford.   Ford was the theorist who singularly laid the theoretical foundatio=
n for my experimental dissertation work at Oak Ridge National Laboratory in=
 the 1960's.  And my major professor (Mack Breazeale) who worked with Ford,=
 was associated in his research with the one who became my  on-site mentor =
at ORNL,  named Victor Pare' (now 84 years of age).  Because Dr Pare' is an=
 expert in material properties, through his training for the PhD at Cornell=
 University-I was circumstantially exposed to valuable concepts involving d=
efects that are not well known the way they should be.  Who could imagine s=
uch a chain of butterfly effect events, occurring in two widely separated-i=
n-time parts of my life, yet having such synergetic influence on my practic=
e of physics.
        By the way, when I was working with single crystalline copper, it w=
as not useable before being work hardened by fast neutrons from the 'swimmi=
ng pool' reactor at the x-10 plant, to pin dislocations.  Had our crystals =
not been so expensive, we envisioned a 'party prank' in which we would give=
 one of our long (right circular) cylindrically shaped specimens to a 'weak=
est' female present at our party and have her with both hands (easily) bend=
 it into a horse-shoe shape.  We would then ask the 'strongest' male presen=
t to come up and restore it to its original configuration.  Of course there=
 would have been great laughter at his futile attempt to correct what would=
 have been so easy for the woman.  The crystal would have been for her, not=
 quite as soft as butter.  But for him, though it would not have been stron=
g as steel,  it would have been a heck of a lot tougher than anybody other =
than ourselves could ever have imagined.  The reason is because of the enta=
nglement of dislocations that would have resulted from the woman's bending-=
dislocations that start at the end surfaces and work their  way inwardly to=
 interact and result in work hardening.
    I say all this, without hopefully boring the majority of list-serve rea=
ders-because I would love to see more of you change your thinking about the=
 abiding great value of the 'simple' pendulum.   Some of the pro's have alr=
eady begun to change their thinking about the pendulum.  Better part of a c=
entury ago they began to divorce themselves in their thinking from it, but =
there is a 'remnant' that is coming back.  The California PhD work of Orteg=
o, under the supervision of Berger, Zumberge, and Wielandt speaks to the ma=
tter.  (And Brett, I think I saw a webpage of yours that references the wor=
k??)  Their state of the art instrument uses optical (interferometric) sens=
ing, but my expectation is that it could just as well have used a capacitiv=
e sensor (yielding a comparable performance level) if it had employed a ful=
ly differential form.  Wielandt still refers to R. V. Jones as the 'ultimat=
e authority' when it comes to sensing of seismic inertial mass motion-wheth=
er for purpose of an error signal based on force feedback, or as is done in=
 my VolksMeter which uses a 'simple' pendulum that is not influenced by an =
actuator.  Just another example of the butterfly effect involves my creatio=
n of the first fully differential capacitive sensor types.  My attempt to g=
et a paper published was met with incredible resistance from some ignoramus=
 referees.  Eventually the editor at Rev. of Sci. Instr.  (Tom Braid) sent =
my paper to Jones, who gave it a positive endorsement, saying that if I wer=
e 'first', then I should be so recognized.  Jones in his report stated that=
 it clearly had twice the sensitivity (of conventional 'differential capaci=
tive' sensors of comparable electrode dimensions) and he 'liked the symmetr=
y', but had 'become too old' to give himself to a math analysis of my devic=
es.  With his death in the late '90's the world lost one of the great pione=
ers of science.  Jones was even honored in this country for his WWII work t=
hat helped to save England from destruction by the Nazi's and which also fa=
cilitated U.S. contributions to the war effort.
        Should you believe that journal referees (and even editors) must be=
 so wise and well trained they surely couldn't be sometimes guilty of incom=
petence (even gross form), listen now to one of the most outrageous example=
s of foolishness in the history of science, involving the laser and the wor=
k of Ted Maiman at Hughes Research Laboratories in 1960.    My knowledge of=
 what happened is another example of 'butterfly effects' taking place in th=
e social events of one's  life.   I first learned about Maiman's treatment =
'at the hands of' an editor of Physical Review Letters while I was at lunch=
 with a famous physicist named  Arthur Schawlow.   Dr. Schawlow (deceased N=
obel Laureate, who was the brother-in-law of the better known Nobel Laureat=
e Charles Townes, with whom I have also had close fellowship-another exampl=
e of the butterfly effect) told me to 'consider it a compliment' that my ar=
ticle that had been submitted to Physical Review Letters had been rejected.=
  On the 50th anniversary of the creation of the first (ruby) laser, Nature=
 chose to engage in a celebration of their publications over the preceding =
century.  In one of the pieces that honored  Maiman, http://www.press.uchic=
ago.edu/Misc/Chicago/284158_townes.html
Townes said of Maiman's paper that was finally published in Nature:  "I bel=
ieve it might be considered the most important per word of any of the wonde=
rful papers in Nature over the past century".
          I just received an email from a horologist who is quite familiar =
with issues of material limitations-how their desire for  a perfect clock w=
ill never be realized, any more than our desire for a perfect seismometer. =
   I do believe, however, that the 'simple' pendulum could be configured to=
 minimize some of the 'show-stopper' features of defects, as they have all =
too often impacted  some instruments.  I may be altogether wrong, but at le=
ast I've done a lot of studies that suggest, why not finally find out from =
experimentation, in just what category to place my claims; i.e., good, bad,=
 or ugly.  In particular, Brett, I would 'sing the hallelujah chorus' if yo=
u and Dave should choose to make the first ever 'force feedback gravitation=
al pendulum' to function as a first of its kind horizontal seismometer/tilt=
meter.  Yes, you have been using something also called by many a pendulum, =
but Galileo who studied the first 'true' (gravitational, 'simple') pendulum=
 would have recommended that you use a different 'descriptor'; just as I pr=
efer to label the torsion instrument that was used by Cavendish to measure =
the universal constant ('big') G due to Newton, by the word 'balance' rathe=
r than 'pendulum'.  The so called torsion 'pendulum' of Cavendish works in =
a radically different way than the gravitational pendulum studied by Galile=
o and Newton.  I believe that the gravitational pendulum, operating with ra=
dically different physics than what describes vertical seismometers-might a=
llow for some important developments.  The key to earthquake predictability=
, should it ever be possible-I view as involving calculations of frequency =
domain type, using measurements at longer periods than are accessible by th=
e vast majority of instruments.  One of the very few instruments that easil=
y operates there (at least without feedback) is the gravitational pendulum,=
 as shown not only in my many experiments and a commercial product as well,=
 but also  in the dissertation of Ortego.  His work was encouraged by Wiela=
ndt, who has said (in effect) that it was time for seismologists to stop ig=
noring some of its important capabilities.  The gravitational pendulum is n=
ot prone to 'displacement to the rails' (whether mechanical or electronic),=
 which was a major factor in the employment of force feedback to begin with=
, for its use in vertical instruments.  Nevertheless, force balance operati=
ng with such a pendulum might open new insights, by providing a first ever =
horizontal instrument of that type.
     My conclusions are influenced by the following line of thinking.  As y=
ou point out, Brett, the sensor does not represent a 'piece de resistance';=
 rather the culprit will always be the components that are most subject to =
the  large 'load bearing forces' of most instruments.  Incidentally there i=
s physics first recognized by the great Richard Feynman (in his article "th=
ere's plenty of room at the bottom" that explains why MEMS seismometers are=
 likely never to perform at the level early builders thought were contempla=
ting.  I could easily at this time get into a detailed discussion of Browni=
an motion (based in the equipartition theorem with which every physics grad=
 student is thoroughly versed) to prove (if my claims concerning defects ha=
ve any measure of truth) that seismometer performance cannot be properly ga=
uged on the basis of the widespread (overly) simplistic calculation of thre=
shold noise determined by atmospheric molecular motion.  It is another one =
of those cases like my previous "let us assume a spherical egg'.  It is abs=
olutely amazing to me, the tendency (toward which we are all prone) to make=
 assumptions for which the  'baby gets thrown out with the wash'.
       Consider the following:  can we employ an axis in which the mechanic=
al part of the force that supports our inertial mass (the bob) is made sign=
ificantly smaller than what is typical, without at the same time introducin=
g something new by our 'cure' that is worth than the 'disease' (brought on =
by defect 'antibodies').  Chris Chapman has pointed out (rightfully) that w=
e don't want to place any strong magnet anywhere on an instrument other tha=
n where it is guaranteed to be stationary.  And though I have not seen here=
 extensive discussions of why ferrous materials should also not be part of =
the moving members; I think it is rather obvious we should not use them und=
er most circumstances.   But I think the 'Chapman constraint' (which he has=
 in times past eloquently described to you folks) can be relaxed for the fo=
llowing.  Consider the axis that is pictured in figure 2 of the following p=
aper, titled "Pendulum sensor using an optical mouse" http://arxiv.org/html=
/0904.3070v1
     Most of the weight of the pendulum is supported by the magnetic field =
gradient of the rare earth magnet shown.  Thus the force of mechanical type=
 involving defects at the contact between the ball-point pen(s) and the low=
er magnet surface is small; i.e., the load bearing force is dramatically re=
duced as compared to what one finds with typical roller type bearings in a =
Lehman, or with 'knife edges' of type found in old analytic chemistry type =
balances to measure mass (they were a compound gravitational pendulum).  Of=
 course it has been well known for years the important requirement for 'edg=
es' --that they be of very hard material, such as agates in the old balance=
s.  The experience of the old master builders of such balances should not b=
e summarily  ignored as we contemplate the business of defect influence.  T=
o measure a mass at a level of a microgram is no small matter.  And if you =
tried to do so with a 'soft' material for the 'edges' of your very best oth=
erwise old instrument you would not be successful, because of the defect pr=
operties of those edges.   Thus it is important that both parts of the axis=
 are hard material-tungsten carbide of the pen point and the alloy type of =
the rare earth.  I also am aware of the fact that there could be some adver=
se features of the surface coating of the rare earth magnet; how it might d=
egrade with time (both chemical and mechanical) and thus impact performance=
..  But isn't it worth some tests?  Note that not every ball point pen type =
will work in this way.  The part that holds the end ball must be ferrous.  =
Many of the inexpensive ball point pens that the Brits like Chris call 'bir=
o' I have found to work.  Simply place the writing point of the instrument =
(as purchased) up against a powerful magnet and find out if it will 'stick'=
 there.  I discovered this quite by accident several years ago while teachi=
ng an undergraduate physics laboratory.  With a little free time away from =
the usual student assistance that was needed, I casually 'tested the streng=
th' of a small rare earth magnet by placing it on the upper frame of one of=
 the steel doors to the room.  Finding it quite hard to then pull away the =
frame, I wondered two things:  (i) would it attract my ball point pen?, and=
 (ii) if so, just how strong would the attraction be?  I was astonished at =
how much weight could be supported by this means, and additionally by what =
resulted after the pen was left swinging.  The Q of the free decay of that =
single-point conical pendulum was so great that it was still moving by a vi=
sually perceptible amount many minutes after I had gone back to help my stu=
dents.  Some of that motion that I later saw was probably due to air curren=
t disturbances; however, subsequent study has shown that it has the very pr=
operties that I'm encouraging you to explore and hopefully exploit.
        So Chris, what about your thoughts on this setup?  Can it avoid a '=
show-stopper' consequence of unavoidable environmental field changes?  If t=
he ferrous holder of the tungsten carbide of the pen points (required for t=
he force of attraction) were at a place of  great motion, then the answer i=
s probably no.  But consider its placement that yields very small oscillato=
ry motion, and the realm of our interest (low and slow, and even 'virtually=
 stopped' if  force feedback were employed).  Might such an axis be used wi=
th a gravitational pendulum to help avoid 'latching tendencies' of the type=
  maverick Peters has in times past suggested (and thus been more than once=
 labeled 'crazy'-and  encouraged by a select few (like outstanding Emeritus=
 Professor of Physics Tom Erber at Illinois Tech) to 'keep on keeping on' a=
nd hope by the grace of God that there might eventually come a time in whic=
h to say I told you so.  Incidentally, Tom told me years ago:  "Randall, wh=
en your work finally becomes mainstream, watch out for the 'steam-rollers'.=
  He recognized the remarkable (dog eat dog) tendency of far too many  in t=
he world of science who try to claim credit for something that was the semi=
nal contribution of another and over which its creator may have labored for=
 decades with nobody other than a select few ever paying attention and prov=
iding him encouragement.
      If you've read everything this far, I commend you (not knowing whethe=
r I should apologize),
Randall

This message has= nearly ‘grown without bounds’, and so you may want to go strai= ght to the last three paragraphs (if you have any interest whatsoever).

  

Brett,     I am glad to hear of how you bake the = spring to hasten stability.  In some of my  experiments performed= in vacuum it was necessary to bake the entire chamber, as is common practi= ce by those who do high vacuum studies.  Otherwise, diffusion pumping = that follows mechanical pumping will never allow one to attain the pressure= s being sought.   These real world frustrations, that are well kn= own to members of ‘vacuum societies’, point vividly to the fact= that the physics is even more complicated than just defects/dislocations i= n an otherwise perfect material that we envision (erroneously) as existing = in no other state than that which we call ‘solid’.  In oth= er words, what has been the focus of our discussion (a spring) is also infl= uenced at the ‘defect’ level even by the gases of the atmospher= e in which it operates!  (And incidentally, the surface of a solid is = the ‘quintessential’ defect that cannot be avoided, since the &= #8216;perfect’ solid must be of infinite extent.) 

        &nbs= p;If one altogether doubts that gases don’t probably always play some= role, at least at some level (perhaps insignificant, but how can such a cl= aim be made without experimental proof) consider an experiment involving a = shape memory alloy that I performed several years ago, which produced the a= rticle titled “Study of friction at the mesoscale using Nitinol shape= memory alloy” http= ://arxiv.org/html/physics/0308077

Yo= u will see from this work what is indisputable evidence that gases can sign= ificantly influence mechanical properties in ways that are not commonly kno= wn.  The quality factor differences for the oscillations that are them= selves of different Q, according to whether the material is in the martensi= tic phase or the austenitic phase—are responsible for a profound R= 16;declaration’ about the importance of defects/dislocations to a spr= ing type oscillator.  And the manner in which significant phase noise = was found to be present, along with ‘Brownian motion’, means th= at the low-level fluctuations are exceedingly complicated and never complet= ely reproducible.  I have facetiously said to colleagues through the y= ears:  “Guess I will have to report my findings in the journal o= f non-reproducible results”.   If such a journal actually e= xists, no bonafide scientist would go read anything published there, becaus= e the very ‘heart and soul’ of science is reproducibility  = ; Consequently, most of my research publications have been ‘open= access’; and the Google search engine seems to have become my greate= st ally.  I was denied promotion years ago in Texas and the dean who s= ealed that decision wrote in her letter, “I hope Professor Peters wil= l eventually be able to say I told you so”--concerning my studies of = the mesodynamics of mechanical systems.   Just as I was retiring = this past spring, one of the most significant publications of my career was= about to be published in Physical Review E (highly esteemed refereed journ= al that is the antithesis of open access publishing).  Less than a yea= r before this, two distinguished French (nonlinear) math/physics experts ha= d found one of my papers dealing with catastrophes.  I had published t= hat article only in one place (Mercer physics personal homepage) believing = (based on painful experiences with referees) that it had about a ‘sno= w ball’s  chance in hell’ of ever getting published ‘= ;conventionally’.  Following the request by my later-to-be co-au= thors, I performed an experiment that resulted in our article “Predic= tion of catastrophes—an experimental model”.  As it was co= ming together I made a claim to colleagues that proved to be ‘right o= n target figuratively’—“there’s not a referee in he= ll who will dare reject this paper, because of the outstanding reputation o= f my co-authors”.  (You can readily read the abstract of our art= icle by simply typing ‘prediction of catastrophes’ into Google = without the tick marks of a literal search. You should be able also to easi= ly with Google find the complete preliminary article that was open source p= ublished on arxiv.)  I mention this to you list-serve readers for anot= her reason—which if it should ever prove to be profound—remains= yet (only after a long time, if ever) to be seen.  If you will look a= t the following paper:  http://physics.mercer.edu/hpage/acceleromete= r/accelerometer.html

You will see wh= at is an event that preceded an earthquake.  It is of the type that I = have seen (in a related context, also by Michael Phillips in Australia; who= calls one type the “Randall effect’) quite frequently as tanta= lizing evidence for ‘precursors’ to earthquakes.  At this = point in time, anybody making a claim for the possibility of meaningful = 216;early warning predictors’ of an earthquake (that could save lives= ) is viewed as either a (i) mystical quack, or an (ii) ignoramus masqueradi= ng as a scientist.  The basis for such a position is not without justi= fication, since true earthquake prediction is  a ‘holy grailR= 17; type of quest, afflicted with the greatest of scientific challenges.&nb= sp; I personally believe, however, that professional seismologists have not= been ‘asking the right questions’ relative to the matter. = ; Just like Nobel Laureate Charles Townes has said the same thing about tho= se who are life science specialists.  It is easy to ‘fold one= 217;s hands’ and say “the problem will never be solved”.&= nbsp;  Certainly more physics has been brought meaningfully into cutti= ng edge biology of late, and the same is sorely needed in seismology. = I have had little success in my efforts to relate meaningfully with profes= sional seismologists, which is part of my reason for coming to your amateur= world several years ago.  One of my ‘successes’ with the =  pro’s was nevertheless realized a few years ago with my BSSA pu= blication titled “Tutorial on gravitational pendulum theory applied t= o seismic sensing of translation and rotation”.  This article wo= uld never have happened had I not met the great John Lahr, who like myself = had a burning passion for science education.   And that passion o= f his ‘spilled naturally’ into your world, which is the place w= here I first learned of John and his legacy.  I was greatly pleased to= learn how the genesis of his passion was undoubtedly part of his earliest = university degree (B.S. in Physics from Rensselaer in 1966). 

      The way my = tutorial materialized is an example of  how the butterfly effect of Ed= Lorenz suggests meaningful extrapolation beyond his original statement (&#= 8220;Can a butterfly flap its wings in Brazil and cause a tornado in Texas&= #8221;, article presented in the early ‘60’s at a Washington D.= C. meteorology conference—about his serendipitous discovery of the &#= 8216;sensitive dependence on initial conditions that is the foundational pa= rt of chaos).  In the broader social sense, I see it (involving system= s even more complex than atmospheric convection) to describe how “lit= tle events of life can unexpectedly take on unforeseeable monumental propor= tions”.  Early after my use of the first fully differential capa= citive sensors I became enamored with the pendulum, one of the oldest instr= uments of science.  Few people know the full extent to which the gravi= tational pendulum in its ‘simplest’ form has impacted our world= ..  Even the foundation theories of fluid mechanics (Navier-Stokes equa= tions) derive from studies of the pendulum that were performed by the legen= dary George Gabriel Stokes.  Those in turn influenced even the world o= f meteorology where Lorenz is considered the father of chaos theory.  = Stokes famous-to-physicists theorem, that derived from his pendulum studies= , describes the manner in which only small rain droplets in clouds have a s= mall enough Reynolds number to remain part of the cloud, while under the in= fluence of the earth’s field of gravity type (little g).  In his= paper generated in 1850  (“On the effect of the internal fricti= on of fluids on the motion of pendulums”) Stokes rightly predicted th= at his conclusions would have significant impact on the world of meteorolog= y.

      =    Another of my experiences involving butterfly effects of = social type (that involved the sequential outworking of more than just one)=  ‘revolved’ around the article that I wrote for the 10th edition of the McGraw Hill Encyclopedia of Science and Technolog= y.  My article accompanies one that was written by Lorenz before his d= eath, and another piece written by a physics theorist who was at Georgia Te= ch (quantum mechanics expert named Joseph Ford.   Ford was the th= eorist who singularly laid the theoretical foundation for my experimental d= issertation work at Oak Ridge National Laboratory in the 1960’s. = ; And my major professor (Mack Breazeale) who worked with Ford, was associa= ted in his research with the one who became my  on-site mentor at ORNL= ,  named Victor Pare’ (now 84 years of age).  Because Dr Pa= re’ is an expert in material properties, through his training for the= PhD at Cornell University—I was circumstantially exposed to valuable= concepts involving defects that are not well known the way they should be.=   Who could imagine such a chain of butterfly effect events, occurring= in two widely separated-in-time parts of my life, yet having such synerget= ic influence on my practice of physics. 

        By the way, when I w= as working with single crystalline copper, it was not useable before being = work hardened by fast neutrons from the ‘swimming pool’ reactor= at the x-10 plant, to pin dislocations.  Had our crystals not been so= expensive, we envisioned a ‘party prank’ in which we would giv= e one of our long (right circular) cylindrically shaped specimens to a R= 16;weakest’ female present at our party and have her with both hands = (easily) bend it into a horse-shoe shape.  We would then ask the ̵= 6;strongest’ male present to come up and restore it to its original c= onfiguration.  Of course there would have been great laughter at his f= utile attempt to correct what would have been so easy for the woman.  = The crystal would have been for her, not quite as soft as butter.  But= for him, though it would not have been strong as steel,  it would hav= e been a heck of a lot tougher than anybody other than ourselves could ever= have imagined.  The reason is because of the entanglement of dislocat= ions that would have resulted from the woman’s bending—dislocat= ions that start at the end surfaces and work their  way inwardly to in= teract and result in work hardening.   

    I say all this, without hopefully boring = the majority of list-serve readers—because I would love to see more o= f you change your thinking about the abiding great value of the ‘simp= le’ pendulum.   Some of the pro’s have already begun = to change their thinking about the pendulum.  Better part of a century= ago they began to divorce themselves in their thinking from it, but there = is a ‘remnant’ that is coming back.  The California PhD wo= rk of Ortego, under the supervision of Berger, Zumberge, and Wielandt speak= s to the matter.  (And Brett, I think I saw a webpage of yours that re= ferences the work??)  Their state of the art instrument uses optical (= interferometric) sensing, but my expectation is that it could just as well = have used a capacitive sensor (yielding a comparable performance level) if = it had employed a fully differential form.  Wielandt still refers to R= .. V. Jones as the ‘ultimate authority’ when it comes to sensing= of seismic inertial mass motion—whether for purpose of an error sign= al based on force feedback, or as is done in my VolksMeter which uses a = 216;simple’ pendulum that is not influenced by an actuator.  Jus= t another example of the butterfly effect involves my creation of the first= fully differential capacitive sensor types.  My attempt to get a pape= r published was met with incredible resistance from some ignoramus referees= ..  Eventually the editor at Rev. of Sci. Instr.  (Tom Braid) sent= my paper to Jones, who gave it a positive endorsement, saying that if I we= re ‘first’, then I should be so recognized.  Jones in his = report stated that it clearly had twice the sensitivity (of conventional &#= 8216;differential capacitive’ sensors of comparable electrode dimensi= ons) and he ‘liked the symmetry’, but had ‘become too old= ’ to give himself to a math analysis of my devices.  With his de= ath in the late ‘90’s the world lost one of the great pioneers = of science.  Jones was even honored in this country for his WWII work = that helped to save England from destruction by the Nazi’s and which = also facilitated U.S. contributions to the war effort.

        Should you = believe that journal referees (and even editors) must be so wise and well t= rained they surely couldn’t be sometimes guilty of incompetence (even= gross form), listen now to one of the most outrageous examples of foolishn= ess in the history of science, involving the laser and the work of Ted Maim= an at Hughes Research Laboratories in 1960.    My knowledge = of what happened is another example of ‘butterfly effects’ taki= ng place in the social events of one’s  life.   I firs= t learned about Maiman’s treatment ‘at the hands of’ an e= ditor of Physical Review Letters while I was at lunch with a famous physici= st named  Arthur Schawlow.   Dr. Schawlow (deceased Nobel La= ureate, who was the brother-in-law of the better known Nobel Laureate Charl= es Townes, with whom I have also had close fellowship—another example= of the butterfly effect) told me to ‘consider it a compliment’= that my article that had been submitted to Physical Review Letters had bee= n rejected.  On the 50th anniversary of the creation of the= first (ruby) laser, Nature chose to engage in a celebration of their publi= cations over the preceding century.  In one of the pieces that honored=  Maiman, http://www.press.uchicago.edu/Misc/Chicago/284158_townes.html=

Townes said of Maiman’s paper= that was finally published in Nature:  “I believe it might be c= onsidered the most important per word of any of the wonderful papers in = Nature over the past century”.

          I just receiv= ed an email from a horologist who is quite familiar with issues of material= limitations—how their desire for  a perfect clock will never be= realized, any more than our desire for a perfect seismometer.   =  I do believe, however, that the ‘simple’ pendulum could b= e configured to minimize some of the ‘show-stopper’ features of= defects, as they have all too often impacted  some instruments. = I may be altogether wrong, but at least I’ve done a lot of studies t= hat suggest, why not finally find out from experimentation, in just what ca= tegory to place my claims; i.e., good, bad, or ugly.  In particular, B= rett, I would ‘sing the hallelujah chorus’ if you and Dave shou= ld choose to make the first ever ‘force feedback gravitational pendul= um’ to function as a first of its kind horizontal seismometer/tiltmet= er.  Yes, you have been using something also called by many a pendulum= , but Galileo who studied the first ‘true’ (gravitational, R= 16;simple’) pendulum would have recommended that you use a different = ‘descriptor’; just as I prefer to label the torsion instrument = that was used by Cavendish to measure the universal constant (‘big= 217;) G due to Newton, by the word ‘balance’ rather than ‘= ;pendulum’.  The so called torsion ‘pendulum’ of Cav= endish works in a radically different way than the gravitational pendulum s= tudied by Galileo and Newton.  I believe that the gravitational pendul= um, operating with radically different physics than what describes vertical= seismometers—might allow for some important developments.  The = key to earthquake predictability, should it ever be possible—I view a= s involving calculations of frequency domain type, using measurements at lo= nger periods than are accessible by the vast majority of instruments. = One of the very few instruments that easily operates there (at least witho= ut feedback) is the gravitational pendulum, as shown not only in my many ex= periments and a commercial product as well, but also  in the dissertat= ion of Ortego.  His work was encouraged by Wielandt, who has said (in = effect) that it was time for seismologists to stop ignoring some of its imp= ortant capabilities.  The gravitational pendulum is not prone to ̵= 6;displacement to the rails’ (whether mechanical or electronic), whic= h was a major factor in the employment of force feedback to begin with, for= its use in vertical instruments.  Nevertheless, force balance operati= ng with such a pendulum might open new insights, by providing a first ever = horizontal instrument of that type. 

     My conclusions are influenced by the follo= wing line of thinking.  As you point out, Brett, the sensor does not r= epresent a ‘piece de resistance’; rather the culprit will alway= s be the components that are most subject to the  large ‘load be= aring forces’ of most instruments.  Incidentally there is physic= s first recognized by the great Richard Feynman (in his article “ther= e’s plenty of room at the bottom” that explains why MEMS seismo= meters are likely never to perform at the level early builders thought were= contemplating.  I could easily at this time get into a detailed discu= ssion of Brownian motion (based in the equipartition theorem with which eve= ry physics grad student is thoroughly versed) to prove (if my claims concer= ning defects have any measure of truth) that seismometer performance cannot= be properly gauged on the basis of the widespread (overly) simplistic calc= ulation of threshold noise determined by atmospheric molecular motion. = ; It is another one of those cases like my previous “let us assume a = spherical egg’.  It is absolutely amazing to me, the tendency (t= oward which we are all prone) to make assumptions for which the  ̵= 6;baby gets thrown out with the wash’.    <= /p>

       Consider = the following:  can we employ an axis in which the mechanical part of = the force that supports our inertial mass (the bob) is made significantly s= maller than what is typical, without at the same time introducing something= new by our ‘cure’ that is worth than the ‘disease’= (brought on by defect ‘antibodies’).  Chris Chapman has p= ointed out (rightfully) that we don’t want to place any strong magnet= anywhere on an instrument other than where it is guaranteed to be stationa= ry.  And though I have not seen here extensive discussions of why ferr= ous materials should also not be part of the moving members; I think it is = rather obvious we should not use them under most circumstances.   = ;But I think the ‘Chapman constraint’ (which he has in times pa= st eloquently described to you folks) can be relaxed for the following.&nbs= p; Consider the axis that is pictured in figure 2 of the following paper, t= itled “Pendulum sensor using an optical mouse” http://arxiv.org/html/0904.3070v1

     Most of the weight of = the pendulum is supported by the magnetic field gradient of the rare earth = magnet shown.  Thus the force of mechanical type involving defects at = the contact between the ball-point pen(s) and the lower magnet surface is s= mall; i.e., the load bearing force is dramatically reduced as compared to w= hat one finds with typical roller type bearings in a Lehman, or with ‘= ;knife edges’ of type found in old analytic chemistry type balances t= o measure mass (they were a compound gravitational pendulum).  Of cour= se it has been well known for years the important requirement for ‘ed= ges’ --that they be of very hard material, such as agates in the old = balances.  The experience of the old master builders of such balances = should not be summarily  ignored as we contemplate the business of def= ect influence.  To measure a mass at a level of a microgram is no smal= l matter.  And if you tried to do so with a ‘soft’ materia= l for the ‘edges’ of your very best otherwise old instrument yo= u would not be successful, because of the defect properties of those edges.=    Thus it is important that both parts of the axis are hard mate= rial—tungsten carbide of the pen point and the alloy type of the rare= earth.  I also am aware of the fact that there could be some adverse = features of the surface coating of the rare earth magnet; how it might degr= ade with time (both chemical and mechanical) and thus impact performance.&n= bsp; But isn’t it worth some tests?  Note that not every ball po= int pen type will work in this way.  The part that holds the end ball = must be ferrous.  Many of the inexpensive ball point pens that the Bri= ts like Chris call ‘biro’ I have found to work.  Simply pl= ace the writing point of the instrument (as purchased) up against a powerfu= l magnet and find out if it will ‘stick’ there.  I discove= red this quite by accident several years ago while teaching an undergraduat= e physics laboratory.  With a little free time away from the usual stu= dent assistance that was needed, I casually ‘tested the strength̵= 7; of a small rare earth magnet by placing it on the upper frame of one of = the steel doors to the room.  Finding it quite hard to then pull away = the frame, I wondered two things:  (i) would it attract my ball point = pen?, and (ii) if so, just how strong would the attraction be?  I was = astonished at how much weight could be supported by this means, and additio= nally by what resulted after the pen was left swinging.  The Q of the = free decay of that single-point conical pendulum was so great that it was s= till moving by a visually perceptible amount many minutes after I had gone = back to help my students.  Some of that motion that I later saw was pr= obably due to air current disturbances; however, subsequent study has shown= that it has the very properties that I’m encouraging you to explore = and hopefully exploit.

   = ;     So Chris, what about your thoughts on this setup?=   Can it avoid a ‘show-stopper’ consequence of unavoidable= environmental field changes?  If the ferrous holder of the tungsten c= arbide of the pen points (required for the force of attraction) were at a p= lace of  great motion, then the answer is probably no.  But consi= der its placement that yields very small oscillatory motion, and the realm = of our interest (low and slow, and even ‘virtually stopped’ if =  force feedback were employed).  Might such an axis be used with = a gravitational pendulum to help avoid ‘latching tendencies’ of= the type  maverick Peters has in times past suggested (and thus been = more than once labeled ‘crazy’—and  encouraged by a = select few (like outstanding Emeritus Professor of Physics Tom Erber at Ill= inois Tech) to ‘keep on keeping on’ and hope by the grace of Go= d that there might eventually come a time in which to say I told you so.&nb= sp; Incidentally, Tom told me years ago:  “Randall, when your wo= rk finally becomes mainstream, watch out for the ‘steam-rollers’= ;.  He recognized the remarkable (dog eat dog) tendency of far too man= y  in the world of science who try to claim credit for something that = was the seminal contribution of another and over which its creator may have= labored for decades with nobody other than a select few ever paying attent= ion and providing him encouragement. 

      If you’ve read everything thi= s far, I commend you (not knowing whether I should apologize),

Randall

 

=

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