Akron Phy sics Club
Meeting Announcement: MONDAY, January 28, 2002 - TANGIER, 6:00 PM
For the first meeting of the last palindromic year in this century, we will hear from our own Joe Walter — otherwise Dr. Joseph D. Walter, Adjunct Professor, Depts. of Civil & Mechanical Engineering, University of Akron — since retiring as Managing Director of Bridgestone/Firestone's Tech Center Europe in Rome [1994-1999] and Director of the company’s Central Research Laboratories in Akron [1990-1994]). Joe will speak on:
VEHICLE ROLLOVER: DO WE NEED A FEDERAL REGULATION?
Minutes, January 28, 2002
Present for our club’s first meeting of the year were David Brown, Vic Burke, Dan Galehouse, Alan Gent, Jack Gieck, Bob Hirst, John Kirszenberg, Bill Jenkin, Leon Marker, Lyle Pauer, Pad Pillai, Darrell Reneker, Gary Roberts, Jack Strang, Ernst von Meerwaal, Joe Walter, and Charlie Wilson. Joe’s Guest, Bryson Allen, is now on our list (with his names in the correct order) and he is cordially invited to future meetings.
Treasurer Dan Galehouse, discovering that our treasury had crept up to an astounding $139.50, announced a not atypical Galehouse innovation: Since, as we discovered in 1990, no bank will accept an account having a balance as paltry as ours, and because that’s too much to carry around in a tin (Tupperware) box, Dan has decreased the dinner charge from $15 to $14, thereby saving the club the cost of an armed guard, and netting out our balance for the evening at $130.50. His aim is to get our total riches back to two digits. We, thus, remain the cheapest club in Akron, our last dues assessment (in the amount of $5) having been two years ago. Which constitutes an invitation for itinerant browsers who (happily) happen to land on this site.
And speaking of that attractive website, our webmaster, John Kirszenberg, brought us up to date on his recent inclusion of our Bylaws, as well as Archives that now permit our programs for the last eleven years to be searched by speaker, by subject, or by date. When fully loaded, they will also contain all of the Newsletter text, including summaries of papers given, for the same period. They are presently complete from November, 1998 to date.
Chairman Ernst then invited Program chairman Vic Burke to fill us in on what to expect for the balance of his (sadly!) remaining term. Vic reminded us that four years ago (January, 1998), in a talk entitled “When Large Particles Collide,” nuclear physicist Decklan Keane, who, after reviewing the history of particle collision experiments, showed us instrumentation that was being assembled at Brookhaven National Laboratory to study ion collisions. For April, Vic has scheduled a friend and colleague of Dr. Keane, Spiros Margetis (KSU) who has agreed to bring us up date on the results of these experiments.
For May, Vic has been successful in scheduling Joe Walter’s friend, Dr. David Quinn, to speak on Chaos Theory. Which, for the moment, leaves a hole for March — one that Vic hopes to mine with the aid of his many contacts at Case Western Reserve University.
Which brought us to our much-anticipated, topical topic for the evening, Vehicle Rollover: Do We Need a Federal Standard? Our own Dr. Joe Walter, currently Adjunct Professor of Mechanical Engineering at the University of Akron (but whose background includes five years as Managing Director of Bridgestone/Firestone's Tech Center Europe in Rome and four years as Director of the company’s Central Research Laboratories in Akron), delivered a detailed, completely objective, technical analysis of the problem — with no effort at faultfinding in the recent sensationalized industrial family feud. We were, in fact, treated to same lecture Joe has been giving to tire-wheel safety seminars for the Society of Automotive Engineers and to his mechanical engineering classes — albeit (happily) without differential equations.
Dr. Walter began by listing the basic tripping mechanisms for vehicle rollover:
Aggressive lane change
Soft soil, e.g., road shoulder
Sudden tire air loss
But Joe’s talk pointed up other significant factors that grossly aggravate the problem. Steering, in some cases (e.g. on the Explorer) becomes counterintuitive for the driver. These include loss of a tire tread, or a rear tire flat, either of which drastically change cornering characteristics (even if the tire does not lose air). Then there is (unfortunately very prevalent) low tire pressure, tire wear, cornering stiffness, and tread grip — the less the better so far as rollover is concerned (although one may end up at an unintended destination). And this summary is by no means complete.
Beginning with a free body diagram examining a refrigerator’s tippiness on a carpet, our speaker showed us a simplified static relationship between a vehicle’s center of gravity, its tire track width, and lateral acceleration, the result expressed as “rollover threshold.” The following is likely to become the basis of a federal rulemaking standard:
Ay/g = t/2h
To show how these factors vary with the class of vehicle, Joe presented the following table. It is apparent that a fully loaded airport van is, by far, the most dangerous passenger vehicle in which to risk a ride. And the bigger the truck, the scarier it is!
|Vehicle||Ctr Gravity Ht||Track Width||Rollover Threshold|
|Sports Car||18 – 20 in||50 – 60 in||1.2 – 1.7 g|
|Compact||20 – 23||50 – 60||1.1 – 1.5|
|Luxury Car||20 – 24||60 – 65||1.2 – 1.6|
|Pickup||30 – 35||65 – 70||0.9 – 1.1|
|Passenger Van||30 – 40||65 – 70||0.8 – 1.1|
|Medium Truck||45 – 55||65 – 75||0.6 – 0.8|
|Heavy Truck||60 – 85||70 – 72||0.4 – 0.6|
Obviously, a way to reduce the likelihood of rollover in designing a vehicle is to increase the static equilibrium (the rollover threshold) by lowering the center of gravity and/or increasing the lateral track width between the tires. But since vehicles are mounted on suspensions (including pneumatic tires), these values change dynamically while driving. In rounding a curve, for example, the effective center of gravity is raised; and as the inside tire is squashed, it reduces the effective track width. Thus, once the vehicle starts to roll, it is very hard to recover.
Tire pressure affects many things, including cornering force, the tendency for a tire to hydroplane, heat build-up leading to tire failure, and critical steering characteristics. Indeed, as Joe demonstrated, when a flat occurs on the rear, the vehicle changes abruptly from understeer to oversteer (and the higher the speed the worse it gets) confusing the driver as his attempted corrections are counterintuitive. Yet, as we learned, most people don’t check their tire pressure once a year! A national study in the U.S. revealed that one in four tires checked in the study was seriously underinflated; moreover, 50% of drivers didn’t know — or even know where to find — the recommended pressure for the tires on their cars. This, Walter emphasized, is in sharp contrast to European drivers, for whom tire pressure “is a religion.”
So: recognizing that many vehicles on the road are unsafe due to low tire pressure, our government is now prepared to require an automatic tire pressure monitoring system that will warn the driver in the event a tire is losing air. The system offered on some cars today, operating off the ABS system (sensing when opposite tires are turning at different speeds) is apparently not considered adequate. There are two competing systems, Joe said. The tire companies favor the $75 solution; the OEM car manufacturers prefer the $5 solution. No surprises there (this writer spent 11 years in Detroit). So we are destined to have new government standards for tires, to be published under the perfectly awful acronym of “TREAD,” whose component words are such a reach that no one, including our speaker, can remember them. And finally, in answer to the title question, it is likely that we will also have (and probably need) a federal rollover standard.
Nota Bene: Although they didn’t seem to fit above, we can’t end this account without documenting several fascinating intellectual nuggets dropped by our speaker:
1) Joe presented a historical summary of tire pressures over the years: Tire pressures have steadily dropped from 80 psi when tires were made of square-woven fabric at the beginning of the century, to 60 psi in the 1920s to 30 psi in the 1930s, to 24 psi in the 50s; becoming 30-36 psi from the 1980s to the present.
2) Surplus Jeeps were not sold after the end of World War II because of rollover worries.
3) Radio Shack offers a very convenient, deadly accurate, digital tire gauge for $10.
4) After the Ford-Firestone divorce precipitated by the Explorer problem, when Michelin was offered a contract, Michelin refused to sell their tires for this application if they were to be operated at only 26 psi.
Meeting Announcement: MONDAY, February 25, 2002 - TANGIER, 6:00 PM
For our February program, our own Prof. David Speer, University of Akron Department of Geology, will speak on:
GEOPHYSICAL RESEARCH FOR THE EFFECTIVE MONITORING OF the COMPREHENSIVE NUCLEAR-TESTBAN TREATY (CTBT)
... a program designed to accurately locate, calibrate and evaluate seismic events in Central Russia and elsewhere, distinguishing anomalous events from natural earthquakes — in cooperation, interestingly enough, with The Federal State Unitary Geophysical Enterprise Bazhenov Geophysical Expedition located in Central Russia.
Minutes, February 25. 2002
With part of our membership basking in the Florida sun (and the Cincinnati sun, and the Canadian sun!), the remainder of the membership available for our club’s February meeting included Dan Galehouse, Jack Gieck, Bob Hirst, John Kirszenberg, Bill Jenkin, Dan Livingston, Leon Marker, Lyle Pauer, Pad Pillai, Gerry Potts, Darrell Reneker, Jack Strang, Ernst von Meerwall, Charlie Wilson, Casey Wynn, and our speaker, Dr. David Steer.
Called upon by Club Chairman Ernst von Meerwall, Treasurer Dan Galehouse — having arrested the worrisome inflation of our treasury balance (as a result of his reducing our dinner price by a dollar) reported a new treasury balance at the close of the evening amounting to $132.50, compared to $130.50 last month — an increase no longer characterized as meteoric. [Actually, nothing that rises should be ever characterized as “meteoric!”]
There followed a brief discussion of our new APC website, during which webmaster John Kirszenberg and your secretary were gratified to learn that members were actually downloading and reading the Newsletter. When this writer asked Webmaster John whether he had noticed the reduced resolution and typographic neatness of our pages, Chairman Ernst announced the good news that our website’s sponsor, the University of Akron, is getting a new server in about a week — which will fix problems like the ones observed, but may confuse browsers until the new server settles down and its handlers learn to cope with any idiosyncratic nuances.
Turning to the business of the evening, Chairman Ernst introduced our speaker, Geophysicist Dr. David Speer, valued member of our club, who turns out to have an interesting background: After doing his undergraduate work at West Point Military Academy (civil engineering), he served the next ten years in the Army (final rank major), during which he was ordered by the Army to study nuclear physics at Cornell. This seems to have been the initial thrust aiming him in a direction which more than qualified him to speak to us (and others) about Geophysical Research for the Effective Monitoring of the Comprehensive Nuclear-Test Ban Treaty.
It was while doing post-doc research at Cornell, working on a related project then funded by the Department of Energy (later by the Department of Defense’s Threat Reduction Agency, and finally laid off to members of the United Nations [etc.?] as treaty negotiations ensued), that Dave got to know geophysical icon Jack Oliver. Oliver is a well-known expert in plate tektonics and a pioneer in the detection of nuclear explosions — which career began accidentally: While looking at a series of seismograms in the 1950s in connection with a paper he was doing, Oliver found one that showed outward compression in all directions. His further research located the source in Nevada — an area that has never been famous for earthquakes. Nuclear testing had been going on (in more than one part of the world) since 1945, and it was megaton blasts at the U.S. Nevada Test Site, of course, that were the source of his seismic events. He later wrote a paper about using seismographs to detect nuclear weapons testing, and was suddenly the world’s expert on the subject.
Our speaker explained the general provisions of the Nuclear-Test Ban Treaty, and how the earth has been instrumented with a multitude of instruments to monitor enforcement, and how these data are processed. His talk was illustrated by a stunning series of animated images projected by his laptop-driven liquid-crystal projector: motion pictures of exploding nuclear devices in combination with colorful stills, tektonic waves propagating merrily around an animated 3-D image of the earth’s sphere, while simultaneously plotting the continuous advance of four parallel seismic sine wave traces (compression waves, shear, impressive, reflections) — a show all by itself worth the price of admission [using a technology destined, this filmmaker opines, to put an end to 35mm slide shows if the capital cost is reduced by an order of magnitude]. Geophysicist Speer also showed us cross sections of the earth, together with plots of depth vs. density, going down through the crust, the mantle, and the iron core. One such section, through the Ural Mountains, contained one million pieces of data on one page. And we saw spectacular aerial views of the Nevada Test Site and the Russian test site on Bikini.
Other graphics included color-coded maps showing areas in which seismic activities are common, as well as the locations of global monitoring stations. These include about 120 seismic sensors detecting north-south, east-west, and vertical waves in the lithosphere (the solid earth), 11 acoustic sensors for the hydrosphere (the oceans), 80 chemical detectors in the atmosphere, capable of sensing nuclear byproducts, and 60 infrasound stations (not all of which are connected at this time). There is/are also something called “rays,” which are created from data received simultaneously from multiple stations. The resulting mass of numbers is recorded by an international monitoring system, which redistributes it, transmitting the data to member countries to make of it what they will. The facility does not analyze the data, nor does it set off alarms.
All of which is a significant part of what David Speer does with his time — having now returned from three months in Russia and Siberia (and lots of other spots) where monitoring stations have been installed. He showed us some of the techniques that are used to achieve the treaty’s objective of zero-testing enforcement, beginning with the process of screening out and rejecting natural events that might otherwise be misinterpreted. Easy discards include events occurring at greater than 20 kilometers in depth, in over 100 meters of water, having an unlikely wave amplitude ratio (in the three perpendicular directions), or in frequency content or other disqualifying integrated analytical wave phase results. For more sophisticated analyses, Dave and his colleagues plug the globally collected data into a (computerized, of course) earth model. Our speaker is currently working on the development and refinement of 3-D algorithms that fit the model, zeroing in to create regional modeling to more precisely locate detonation sites.
The treaty and the process of enforcement have lots of political overtones, it turns out, not the least of which was the U.S. Congress’s refusal to ratify the treaty in October, 1999, primarily to embarrass Bill Clinton[!], which objective they accomplished — without doing much for the nation or the objectives of the project — or world peace for that matter. [Not that any of our recent presidents has needed much assistance at generating embarrassment (Editor’s Note)]. Although neither the new Administration nor the Congress seems eager to move forward on this issue, 9-11 has increased interest in it.
Nuggets we picked up during later discussion with our speaker:
1. Shades of the Cold War, the Russians are uncooperative at releasing any of their data.
2. The biggest nuclear explosion ever was the Soviet Union’s 1000 megaton bomb on Bikini.
3. When that one went off, being close to a natural fault, it set off two earthquakes of about Magnitude 5 on the (logarithmic) Richter Scale.
4. The U.S. Army has developed the smallest device produced to date. It will fit in a soldier’s [or anybody else’s!] backpack.
5. Comparing natural events to nuclear ones, the energy released by a 100 megaton bomb is roughly equal to that released by a Magnitude 5 earthquake.
6. Our speaker found his glorious graphics of exploding nuclear bombs on the Internet!
Meeting Announcement: MONDAY, March 25, 2002 - TANGIER, 6:00 PM
At our March program, we will be privileged to hear Dr. Alper Buldum, who hails from Turkey, but received his graduate training in the U.S., and has been Assistant Professor of Physics, at The University of Akron, since Fall, 2001. Dr. Buldum will substantially enlarge our knowledge about:
NEW MATERIALS FOR FUTURE APPLICATIONS
These structures have extraordinary physical properties. They have attracted a great deal of interest in recent years because of their astonishing strength — which exceeds that of any other fiber.
Minutes, March 25, 2002
Valiantly attending this meeting, despite the snowstorm that had passed through Akron only hours before, were our speaker Alper Buldum and his wife Asli; Victor Burke; Daniel Galehouse; Robert Hirst; John Kirszenberg; Bill Jenkins; Leon Marker; Lyle Pauer; Darrell Reneker; Ernst von Meerwall; Charles Wilson; Casey Winn; David Wynn; and Joe Angeles.
The brief business meeting attested to the continued solvency of the organization and the existence of confirmed speakers not only for the two remaining meetings this season but also for the September meeting. Program chair Victor proposed that the Club be polled about the desirability of conducting a trip sometime this summer to take in a presentation by the new planetarium at Cleveland’s Museum of Natural History. Webmaster John agreed to solicit input via the website, on this issue as well as on the more general question, which arises at regular intervals, whether Club meetings might be held during some or all of summer. Chair Ernst reminded the Club that election season will soon be upon us, and Assistant Secretary Charlie agreed to accept nominations for next year’s officers. According to our bylaws the slate needs to be in place by the April meeting, with elections completed by the May meeting.
The evening’s speaker, Prof. Alper Buldum of UA’s Physics Department, had kindly agreed on relatively short notice to speak to us, for which favor Club members expressed their gratitude. He provided us with a fascinating and polished PowerPoint presentation on the subject of carbon nanotubes, in which he is a theoretical and computational expert. These materials have attracted much interest in recent years as possible candidates for diverse technical applications in space technology, engineering, energy storage, sensors, interfaces, and in a variety of nanoelectronic devices. These molecular gadgets were first synthesized and characterized in 1991, being created either by arc discharge (as are buckyballs) or by laser ablation. They are generally between 7 and 300 Angstroms in diameter (the single-shell norm being 14 Angstroms, with concentric multi-shell assemblies correspondingly larger), and several micrometers in length. They are enormously strong – Young’s moduli are on the order of one Terapascal -- but at the same time very tough: they recover elastically even if they are bent enough to kink, thus making excellent tips for AFM probes. Two main variants are the armchair and the zigzag arrangement of the hexagonal carbon assemblies with respect to the tube axis and diameter.
Most of the unique properties of carbon nanotubes are direct consequences of their two main structural attributes, i. e., their perfect graphite/diamond crystalline order, and the relatively small number of atoms involved. Both of these attributes, of course, enable or at least considerably aid the application of standard solid-state quantum theory to this class of objects. The remainder of the talk provided the most satisfying conceivable set of illustrations of the dominance of structure in the properties of a material. For example, the modest change from zigzag to armchair structure affects the electronic band structure by so greatly changing the gap between valence and conduction electron bands as to turn the excellent conductor into an intrinsic semiconductor. In either, step-like non-Ohmic behavior is the norm. Rolling nanotubes over “flat” surfaces results in a highly regular stick-slip behavior; the energy of orientation with respect to the substrate’s atomic structure is affected by incommensurability and imperfections.
Electronic junctions between crossed tubes display a variety of useful attributes. Alignment and orientation have strong effects on junction resistance, producing periodicities in I vs. V curves, including regions of negative differential resistance. Such effects are of interest for applications in amplifiers and switches as well as sensors and transducers, leading, for example, to atomic-scale switching by mechanical motion. The intercalation of ions within nanotubes, and between their stacks, has been observed to confer sizeable advantages over the use of graphite in battery applications, simply by virtue of the increased filling fraction made possible by the tubes’ thin walls. In the same vein, nanotubes are envisioned for use as chemical sensors, changing their electrical conductivity in the presence of intercalated or adsorbed donor or acceptor molecules.
Conductive nanotubes with their narrow points make excellent electric field emitters, permitting extremely high current densities even as net currents are kept low. A pentagonal shape of tube end caps is particularly advantageous when minimal angular dispersion of field lines is desired. Beyond use in STM/AFM microscopy and spectroscopy, applications include low-voltage flat-panel displays, for which crude prototypes have been demonstrated.
This writer was most impressed by the relatively complete theoretical understanding of carbon nanotubes, and by the consequent mature state of agreement among theory, computation, and the extensive experimental evidence in hand. As the recent multitude of carbon nanotube sessions at the March APS meeting indicates, the great promise of these materials has inspired the material science professions to explore both their properties and their possible applications.
Faithfully recorded for the Secretary,
Ernst von Meerwall
AND NOW — as if you hadn’t guessed — PLEASE let me hear from you (ideally without prompting!) confirming (or sadly denying) your reservation for next Monday, April 22nd, by Thursday evening, April 18th, for Dr. Maretis program. See you there!
Meeting Announcement: MONDAY, April 22, 2002 - TANGIER, 6:00 PM
Our club having last heard about “When Large Particles Collide,” from Dr. Decklan Keane’s in January, 1988, Dr. Spiros Margetis of Kent State University Department of Physics, whose current research involves collisions of heavy nuclei at ultra-relativistic energies (as they offer unique opportunities to study the behavior of nuclear matter under extreme conditions of temperature and density) has consented speak to us about the latest at Brookhaven’s
RELATIVISTIC HEAVY ION COLLIDER (RHIC)
Minutes, April 22, 2002
Present for our first meeting with the weather now hinting at spring, were regulars David Brown, Tom and Marie Brooker, Vic Burke; Dan Galehouse; Jack Gieck; John Kirszenberg; Bill Jenkin, Leon Marker; Lyle Pauer, Pad Pillai, Darrell Reneker; Jack Strang, Ernst von Meerwall, and Charlie Wilson.
Called upon by Chairman Ernst, Program Chairman Vic Burke reminded us of the April speaker announced above — and , as a last program to be scheduled on his watch (L), told us we would be treated to a tour of the Liquid Crystal Institute for our first meeting in September! Then, as an extra added attraction, he proposed that we rent a bus or pool cars for a trip this summer to the brand new, state-of-the-art planetarium of the Cleveland Museum of Natural History. Going out with the kind of multicolored five star cluster we have come to expect, Vic is giving up his outstanding trusteeship as our Program Chairman to devote a year (anyway) to travelling and to slipping more diligently into his grandfatherly role — taking with him a positively viscous round of thanks, affection, and good wishes from the grateful members of this club. And we’ll let it go at that for now, since we’ll still be seeing him when he can make an occasional meeting next year.
Whereupon Treasurer Dan Galehouse, successfully fulfilling his continuing objective to keep our treasury in check, was obviously pleased to announce that our cash assets had grown from $93.50 last month to an underwhelming $94.50 by the end of the evening. At which point Secretary Jack Gieck assured the membership that Tom Dudek, whom we have missed, is just fine, but confesses to having accepted an assignment teaching chemistry on Monday and Wednesday evenings. And he promises not to do it again.
It now having become feature attraction time, after some extended (albeit fruitless) efforts to achieve compatibility between computer and video raster formats, Vic Burke introduced our speaker, “newly minted Tenured Associate Professor of Physics, Kent State University” Dr. Spiros Margetis, whose research, at both CERN and Brookhaven National Laboratory, has involved collisions of heavy nuclei at ultra-relativistic energies, as they offer unique opportunities to study the behavior of nuclear matter under extreme conditions of temperature and density. Dr. Margetis delivered on his promise to update us on the latest at Brookhaven’s Relativistic Heavy Ion Collider.
The Relativistic Heavy Ion Collider (RHIC) at the Brookhaven site is a world-class scientific research facility that began operation in 2000, following 10 years of development and construction. Hundreds of physicists from around the world use RHIC to study what the universe may have looked like in the first few moments after its creation. RHIC drives two intersecting beams of gold ions head-on, in a subatomic collision. What physicists learn from these collisions may help us understand more about why the physical world works the way it does, from the smallest subatomic particles, to the largest stars.
Here, as Dr. Margetis explained, one works for ten years preparing for an experiment before getting his (her?) turn at the machine — at which time he beholds some truly remarkable things happening: Streams of gold nuclei, accelerated by sequential electrostatic impulses and focused by electromagnetic fields (using 1740 superconducting magnets if you must know), careen around an evacuated circular track several kilometers in diameter — a track whose interior is kept at a temperature of + 4.5° Absolute. The nuclear nuggets are driven by 100 GeV, reaching velocities of 99.99% the speed of light — increasing 200 times in mass as a result of relativistic effects! Was Einstein right on or what? RHIC consumes 15 megawatts of power(!) and operates continuously for months at a time.
[Editor’s note: It is apparent that our language needs a stronger punctuation mark for occasions like this — perhaps an exclamation point raised to the 23rd power. I remember how impressive it was when, on the board of another Long Island facility in the 1970s, I learned that Radiation Dynamics, with a polymer-crosslinking machine operating at one MeV, could accelerate electrons to 80% of the velocity of light, increasing their mass by a detectable amount. Their neighbors at Brookhaven are now using 100 GeV and achieving a mass increase of two orders of magnitude!]
So when these two particle beams confront each other, their relative velocity inching even closer to c, the probability of their hitting head-on is actually relatively small. But using some beautiful computer graphics, Dr. Margetis showed us how the totality of these collisions can be assessed: by measuring energy density (which can be considerable), statistical particle distribution, mass vs. slope parameters of plotted functions, and other increasingly arcane and/or abstruse (from this writer’s perspective) techniques.
The Au nuclei that hit squarely enough (and it happens about five times per second!) soar to temperatures of the order of 1012 degrees. And when things get this hot, we don’t have to specify a scale — adding or subtracting 32° (or 273° for that matter) doesn’t matter much. The objective is to achieve a density ten times that of a proton. At such densities it no longer makes sense to speak of individual nuclei — or even individual quarks, mesons, pions, Higgs bosons, or whatever. As Vic Burke puts it:
“The goals are (1) to create a primordial state of matter (for 10–23 seconds) — a hot soup of quarks and gluons, a condition where the quarks 'forget' where they came from and so are free to recombine as the hot soup evaporates sending out streams of elementary particles; (2) to collect a complete set of data for each collision; (3) to analyze the data for new and surprising results.”
And, indeed, new and surprising results have been achieved. There is evidence of explosive behavior within the plasma, and indeed the existence of “a new state of matter” as was forecast in some journals when the work was commenced (beginning with Pb-Pb instead of Au-Au). Best of all, the experimenters did not manage to produce a mini black hole as predicted by some — a singularity into whose massive tiny maw the earth would be drawn — perhaps along with the moon, and then maybe the rest of the solar system . . . Would it bring the universe to a lower energy state?
All of which is reminiscent of a similar conversation at the Trinity Site on July 16, 1945.
SO THEN: Since we’re all still here despite those doomsayers, to celebrate that event and to get together one last time before summer, please let me hear from you confirming (or denying) your reservation for next Monday, May 20th — that’s a week early because of Memorial Day, by Thursday evening, May 16th. See you there!
Meeting Announcement: May 20, 2002 - TANGIER, 6:00 PM
For our last meeting before our summer hiatus (and before the Autumnal Equinox!), Program Chairman Vic Burke has successfully booked a knowledgeable speaker on a much-requested subject. Dr. Dane Quinn, Associate Professor of (perhaps surprisingly) Mechanical Engineering, The University of Akron, will clarify our thinking about:
Minutes, May 20, 2002
Present for our last meeting of the season were David Brown, Tom and Marie Brooker, Vic Burke, Stu Clary, Jack Gieck, Bob Hirst, John Kirszenberg, Bill Jenkin, Leon Marker, Pad Pillai, Darrell Reneker, Dick Sharp, Jack Strang, Ernst von Meerwall, and Joe Walter.
Switching roles from that of treasurer pro tem (in Treasurer Dan Galehouse’s absence), our intrepid Chairman Ernst von Meerwall called upon Program Chairman Vic Burke, who, after announcing the above September meeting as his final act, made a brief commencement address proclaiming his freedom to travel extensively with his wife for the next year or so. His graduation to free agent precipitated an ovation for the three years of outstanding programs Vic has arranged for the club — frequently in cooperation with other members. He leaves office with our thanks (but we’ll see him when he’s in town).
Whereupon, in accordance with Chairman-Emeritus Charlie Wilson’s by-laws, Chairman Ernst launched our annual (perfunctory) election of officers. Since, as he said, “There has been no armed resistance to the present officers remaining in their respective positions for another year — except, of course, for our Program Chairman, who, naturally, needs two people to substitute for him,” the following became the proposed slate of officers for the coming year:
|Chair||Ernst von Meerwall|
|Assistant Secretary||Charlie Wilson|
|Program Co-chairmen||Bob Hirst & John Kirszenberg|
|Program Vice-Chair||Leon Marker|
|Volunteer! Webmaster||John Kirszenberg|
(Come to think of it, all of them volunteered by agreeing to serve — thanks gentlemen!)
Following a (duly seconded) motion by the secretary, the lucky fellows above were waved into office by a show of right hands, including (it is herewith recorded) their own. Ernst reminded this group that the resulting Executive Committee will “do lunch” during the summer to plan the coming season.
At which point, Vic Burke introduced our speaker, Dr. Dane Quinn, who, with a Bachelor’s degree from Georgia Tech and a PhD from Cornell, couldn’t have better credentials to have been tenured this year as Associate Professor of Mechanical Engineering, The University of Akron — where he has been teaching for eight years. His subject, as promised, was Chaos Theory.
Dr. Quinn suggested that if we looked up “chaos” on the Internet we would find more hits than one could read in a lifetime. [I did; he’s right. Typical Entry (Page 19): Chaos Theory and Causality: An Overview of the Transformation of Causality as Bifurcations of Key Parameters Affect the Ability to Predict with Certainty.] He observed that although the subject of chaos or chaotic systems has appeared in many different kinds of literature for fifteen years, there is no generally accepted agreement on its meaning. So our speaker began by giving us a practical-sounding one of his own.
From a physics and an engineering perspective, Dane explained, a system is chaotic if one has an irregular unpredictable motion, or dynamics of a system, that arises from a very predictable and regular set of equations. Such chaotic systems are non-linear, recurrent and have a very sensitive dependence on initial conditions. Being non-linear, they are not particularly amenable to analysis.— although some ground-breaking work on analysis was started as long as a hundred years ago by Poincaré. Although they are recurrent, unlike a periodic motion, for example, non-linear systems never repeat themselves in exactly the same way. And because initial conditions are almost never known exactly, there is always some uncertainty (even noise in the system) that leads to uncertainty in the results — an uncertainty that grows with each iteration. Real-world examples cited by Dr. Quinn included the unpredictable vortices left in the wake of jet aircraft.
For clarification of what we were thinking about, Dane offered us a running joke in the community that studies such things: Defining a non-linear function, or a non-linear equation as “any equation that is not linear” is like defining zoology as “any animal that is non-elephant” (since almost all animals are not elephants; and almost all equations are not non-linear). [Which, if you’ll pardon another interruption, reminds this writer of theologian Dr. Martin Marty’s not entirely facetious definition of “spirituality” (which stumps most dictionaries): “Spirituality is what you have left when you take out everything you don’t like about religion.”]
Poincaré and other pioneers never really had a chance, it seems, because analysis of chaotic systems was impossible before the development of modern high-speed computers. Which led directly into a delightful series of demonstrations piped from our speaker’s laptop computer into a digital projector, in which he began with colorful plots of non-linear exponential equations beginning with answers to the question, “What are the zeros of z3 + 1 = 0 ?”
The equations got stickier after that, but the audience was obviously with the speaker (since members continually interrupted with questions) as we watched the superimposed slightly-wandering, drifting curves resulting from successive iterations, eventually filling the entire page; however, demonstrating that in all this seemingly random activity, there is structure— as became apparent with the gradual appearance of the strange attractor, a pattern defining a more heavily trampled path of the accumulating plots. We even saw some “live” calculations in response to questions from the audience — one calculation reiterating a thousand times as the resulting worm of its plotted curve oozed across the projected grid.
Had the audience let our speaker get on to the practical applications he planned to speak about, your editor is guessing that they probably would have included the continuously-shifting planetary orbits in our Solar System (which, if I'm interpreting what I learned correctly, have a sufficiently consistent strange attractor that they haven't collided in 4.6 million years. . . . And then, zooming back and widening out, there's the revolution of stars around the galactic center of the immense cosmic carousel that is our Milky Way.
As he revealed the wonders of his remarkable field of study, it was apparent that our speaker was genuinely moved by the noumenal experience of finding structure in what might otherwise might be perceived as random activity — more than once calling it “beautiful!” And it is. In 1936, Dr. William Sheldon wrote that “the mind that cannot feel what it knows becomes spiritually impoverished.” Dane Quinn’s isn’t.
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WE WELCOME VISITORS!
Meeting Announcement: MONDAY, September 23, 2002 - TANGIER, 6:00 PM
IT IS THAT TIME OF YEAR! On the very day when the collision of the Ecliptic with the Celestial Sphere echoes silently across the land (as the sun heads south with our summer weather), we will celebrate the Autumnal Equinox with our first meeting of our new season, NOT at the Tangier this time, but at Henry Wahner's German restaurant. 1609 E. Main Street, Kent, gathering at 6:00 P.M, dinner at 6:30. From “Henry’s” we will repair to Kent State’s famous LIQUID CRYSTAL INSTITUTE, where Prof. Philip Bos, Associate Director of the Institute as well as Associate Professor of Chemical Physics, will speak to us about the:
BASIC PHYSICS OF LIQUID CRYSTAL DISPLAYS
And Dr. Bos will treat us to a TOUR OF THE LIQUID CRYSTAL INSTITUTE!
Minutes, September 23, 2002
Present for our first meeting of our fall schedule (at Henry Wahner's German Restaurant in Kent) were David Brown, Tom Brooker, Sam Fielding-Russell, Dan Galehouse, Jack Gieck, John Kirszenberg, Bill Jenkin, Leon Marker, Pad Pillai, Darrell Reneker, Gary Roberts, Jack Strang, Ernst von Meerwall, Charlie Wilson, and a delegation of Wynns: regulars David and Casey, plus a bevy of lady Wynns, Dave’s wife, Susan and Casey’s sister, Carly. And for his first visit, we had Steve Kraus, brother-in-law of Stu Clary (if you are keeping track of the relationships). We hope we’ll see more of those who graced us with their presence for the first time (you’re on our e-mailing list, Steve).
While waiting for the obviously daunting administrative task of getting our dinner checks, Chairman Ernst von Meerwall dwelled briefly on an obligatory business meeting — during which Treasurer Dan Galehouse advised that the treasury of the club hovered comfortably at $100.38; and Secretary Jack Gieck announced that, thanks to the efforts of Webmaster John Kirszenberg, the Akron Physics Club Archives in the club’s website are now complete, and that papers we have heard (or given) during the last 11 years may now be called up in search mode by topic, speaker, or date. After which Program Co-chairman Bob Hirst gave us some Previews of Coming Attractions.
When we were finally sprung from the restaurant, we repaired to the Liquid Crystal Institute on the Kent State campus, domain of our host and speaker, Dr. Philip Bos, Associate Director of LCI, Associate Professor of Chemical Physics, who led us to a seminar conference room. Here he presented selected samples from three of his beautifully illustrated (by means a laptop-driven Proxima projector in combination with an overhead) lectures on the Basic Physics of Liquid Crystal Displays, as well as some of the work of the Liquid Crystal Institute and the personnel who carry it out.
Liquid crystals, “nature's delicate phase of matter,” our host explained, are birefringent fluids — organic molecules whose physical form (we later saw a bottle containing a small sample) is that of a viscous, translucent liquid. (The white translucence we saw disappears and the contents look and behave like water, it seems, when the temperature is raised to about 80° C.)
Although they are non-polar and are constantly thermally fluctuating, the molecules in the liquid crystal do have a local order, an aggregate general direction whose alignment is easily encouraged — especially by an electric field that induces a dipole moment in the individual molecules. The effect of turning this field on or off is instantaneous, blocking or unblocking the polarized light traveling through the layer of crystal. Our speaker also introduced us to some of the mathematics used to quantify the degree of nematic order, the angular deviation from that of the “director’ — the controlled common direction of the long, parallel molecules — as well as the “energy density” involved as variations occur within the crystal.
These unique materials (first studied in the 1930s) need just a “hint,” our speaker explained, to restore the forces that try to keep the director field uniform. To this end, when they are sandwiched between the surfaces of glass plates (which are only 5 microns apart), the underside of the “alignment layer” coating is usually brushed with a (precisely emplaced) velvet cloth to establish the direction of the parallel molecules(!). A deflection of 100 microns of the fine velvet fibers in a nap perhaps 3 mm long, is sufficient to invisibly “score” the surface — thus aligning the top molecular fragments in the liquid crystal film. The finished sandwich in the display has five layers, the top and bottom “bread” layers being crossed-axis polarizing filters. LCD components are the operating essence of applications ranging from digital wristwatches to flat monitors for computers and television screens — the latter two being lit from behind by fluorescent tubes. Dr. Bos took us on a tour of the Institute, including his laboratory, whose primary purpose, he explained, is to verify the conclusions that are the output of the teamed components of his remarkable computer — a cluster of 16 stacked dual processors capable of direct numerical solutions in Maxwell-equation calculations.
We also saw some fascinating LCD applications, including a welder’s helmet whose filter acts as a shutter, automatically dropping in microseconds from essentially transparent to many stops darker when an arc is struck. Nearby was a reflector application, a framed, “permanent storage” display of an incredibly high-resolution map. But the most dramatic demonstration for this visitor was looking through the tall glass wall that enclosed a roomful of prototype machinery when our host invited one of our number to flip what appeared to be a light switch on the wall — instantly opaquing about a hundred square feet of picture window.
Our collective thanks have been dispatched to our thoughtful host -- who not only provided us with handouts of his beautiful graphics (loved by the writer of minutes!), but he even provided us with parking stickers(!). He has been added to our e-mailing list, and has been cordially invited to our future meetings. We hope he will find some of them sufficiently intriguing to lure him over to the Tangier.
And speaking of the next one of those, you have the breaking news of our next one at the top of this (early this time!) Newsletter.
Meeting Announcement: MONDAY, October 28, 2002 - TANGIER, 6:00 PM
Police academies, the FBI, military services and criminal justice classes across the U.S., Canada, and even China have all heard from our October speaker, forensic scientist Peter McDonald, who has become the nemesis of more than a dozen now-convicted felons who made the mistake of leaving tire tracks at the scenes of their crimes — nailing themselves as surely as if they had left their fingerprints on a murder weapon. McDonald will be explaining some of the intricacies of his specialty:
TIRE FOOTPRINT EVIDENCE
Minutes, October 28, 2002
A near-record attendance for our October meeting included Bill Arnold, who brought Goodyear colleagues Richard Deneen and Seth Ankrah with him (we hope to see any part of this trio at future meetings — they are cordially invited herewith). Also present for excellent Tangier Shishkabob (although the servings arrived at such a languid pace that our speaker had to forego his dessert so that some of the following could get their entrée — during his presentation!) were David Brown, Dan Galehouse, Alan Gent, Jack Gieck, Bob Hirst, Bill Jenkin, Steve Kraus, Dan Livingston, Leon Marker; Pad Pillai, Darrell Reneker; Gary Roberts and son John, Sam Fielding-Russell, Jack Strang, Ernst von Meerwall, Joe Walter, Charlie Wilson, and Casey Wynn, who subsequently introduced his mother, Susan — whom we first welcomed last month at our Liquid Crystal Institute meeting.
After Chairman Ernst von Meerwall had all of our guests introduced, he called upon Treasurer Dan Galehouse for a report on our wealth — which, it turned out, now amounts to $160.38, an amount so adequately adequate for anticipated needs that Dan “would rather not augment the treasury above its preset value,” even though the Tangier has increased our meal fee by a dollar. So, in the absence of any disrupting public protest, our meal charge will continue to be $15 for the balance of the year (which is to say for the remaining November meeting).
Called upon for Previews of Coming Attractions, Program Chairman Bob Hirst announced that in January we will hear from Prof. Gustavo Carri of the University of Akron’s Department of Polymer Science, whose topic (with a title of impressive length) couldn’t be more appropriate for Rubber City physicists, engineers and chemists who, during their careers, have been charged with making things out of elastomers and other polymers. To wit: Polymer Architecture and the Influence of External Forces on the Statistical Properties of Semi-Flexible Polymers.
Whereupon (with some of those present having not yet received their entree!) your Secretary turned on a 5-minute video piece hosted by Leon Bibb describing Forensic Scientist Peter McDonald, whose degree is in architecture (in which field he still works occasionally), but who elected early retirement as Firestone’s Director of Tire Design — and, depending upon the venue, is also a well-known artist whose media include painting (sometimes on a derelict boat-hull substrate!), sculpture, and stained glass windows. But Pete is best known for his ability to study a tire track (or a photograph of same with any reliable indication of scale in the picture), and then identify the tire size, the tire model, what company made it, when it was probably made, and what kind of a vehicle it is likely to be on. If a suspect has such a vehicle, he literally uses fingerprint ink to achieve a positive identification — not only by local “accidental characteristics,” e.g., cuts or minute scars left by sharp stones, but by more subtle clues, including deceleration marks., uneven tread wear, skid depth, the appearance of wear indicators, and the slight discontinuities in the pitch of the tread deliberately introduced into the tire mold for noise treatment — to name some of the abstruse tools used by forensic scientists of our speaker’s persuasion.
Instead of dwelling on these arcanities, our speaker opted for telling us about some of his recent adventures in helping police catch some singularly bad guys — beginning with a serial killer in Largo, Florida, who had dispatched half a dozen prostitutes. By the time McDonald was called into the case, materials of forensic interest found on some of the nude bodies included a few carpet fibers, a dog hair, and a cigarette butt. The police had already photographed what Pete described as an excellent series of extended tire tracks “photographed vertically, with oblique lighting, and a tape measure running the length of the track.” But, apparently believing that their consultation with McDonald wouldn’t lead to much (since the FBI had been of little help and had, in fact, misidentified the tire), they sent Pete only a little Polaroid photo.
“As I told them on the phone, I immediately recognized it as a tire I had designed a few years earlier when I was at Firestone,” our speaker recalled, thereby earning the title among the Largo police officers as “the father of the Firestone.” Noting that some subtle changes he had subsequently made in the tire design were absent, thereby fixing he tire’s “code,” he traced the tire back to the Florida dealer from which the tire had been purchased — from which he eventually was able to get the name of the purchaser. But this was hardly enough to assure a conviction.
So, as Pete explained, “we cooked up a ‘tire recall’ …” The abbreviated version of the Pete’s very entertaining story is that the felon and his current girlfriend were given four new replacement tires so McDonald could create professional-quality tire footprints for analysis and comparison with photographs of the tracks found at the crime scene(s). Thus inspired, remembering the other scraps of forensic evidence listed above, the police also invented a “new dog-grooming service” (staffed by female police officers) that offered the couple a free shampoo and grooming for the woman’s somewhat rare breed — whose hair sample matched the single strand found on one of the bodies. And, yes, under another microscope, fibers from the living room carpeting in the couple’s home also matched those clinging to the skin of one of the other victims. (The cigarette butt led to a fourth positive identification.)
Interestingly, the girlfriend person (who might well have become the next victim!), had not only given up prostitution, but was studying at a nearby Florida university majoring in marketing. Grateful for the free services her pet had received, she provided the friendly ladies of the new grooming services with some gratuitous marketing advice.
By the time everyone (else) had been served his/her dessert, McDonald showed us some of the graphics he generates in the course of his work, including a printed tire track several yards long when unfolded. It turned out to have come from the vehicle driven by Oklahoma City bomber Timothy McVeigh! Brought into the case by the defense, tire expert McDonald had provided determinate information the defense lawyers didn’t want to hear, and certainly didn’t want disclosed in court — putting Pete into an ethical conflict of interest that was solved when McVeigh was convicted on other evidence.
Meeting Announcement: MONDAY, November 25, 2002 - TANGIER, 6:00 PM
For the last meeting of the only palindromic year in this century, we will hear more about a pair of currently hot topics in nanotechnology.
Prof. Liming Dai of the University of Akron’s Department of Polymer Engineering will speak to us on
ALIGNED CARBON NANOTUBES
Minutes, November 25, 2002
In contrast to the Tangier’s overwhelming kitchen/server problem in October, our top-of-the-line waitress, Megen, swiftly served a delicious concoction of “Beuarre Blanc” (chicken breast in wine and butter) to Dave Brown, Dan Galehouse, Tom Dudek (welcome back, Tom!), Sam Fielding-Russell, Jack Gieck, Bob Hirst, Bill Jenkin, John Kirszenberg, Leon Marker, Robert Mallik (and the same to you, too, Robert!), Darrell Reneker, Dick Sharp, Jack Strang, Ernst von Meerwall, and Charlie Wilson.
Called upon by Chairman Ernst von Meerwall, Treasurer Dan Galehouse declared that the Club was still in the black(!). Recognizing Lord Kelvin’s admonition to measure what we are talking about, he later quantified our net wealth at $145.38.
When asked for Previews of Coming Attractions, Program Chairman Bob Hirst told us about the program announced at the top of this page — one that couldn’t be more appropriate for Rubber City physicists, engineers and chemists who, during their careers, have been charged with making things from elastomers and other polymers.
Whereupon Chairman Ernst introduced our, Prof. Liming Dai of the UA’s Department of Polymer Engineering, who treated us to a beautifully-illustrated (Power-Point) presentation on: Optoelectronic polymers and Aligned Carbon Nanotubes.. Dr. Dai received his engineering degree in China, earning his PhD in Australia, where he spent the next ten years as a research scientist.
Polymers, our speaker pointed out, have long been used as electrical insulators. For as long as most people remember, metal wires have been coated with plastics of various kinds to insulate them (displacing the layers of braided natural fibers that some of us knew in our youth). But now, as Dr. Dai explained, a variety of polymers having a conjugated backbone (with alternating single and double bonds) have been synthesized with remarkable, electrically-conductive, magnetic, and optical properties of their own.
These polymers even include polyisoprene, made of what most of us have long known as the natural rubber molecule. The polymers that work all have charge carriers and what amounts to overlapping electron clouds. Their unusual properties, our speaker said, are due to “substantial π-electron delocalization along the polymer backbone.”
Dr. Dai showed us the structural changes involved in creating these unusual materials, as well as their color changes. “We have elucidated the mechanism through which the conductivity of ‘I2-doped’ [I for induced] non-conjugated polydiene rubbers arises” he added, “and we have demonstrated photo-lithographic generation of conducting patterns for opto-electronic applications.”
Our speaker explained that he has developed a number of light-emitting diodes with novel features for multi-color displays. And these are capable of operating on garden-variety household AC current. These light-emitting polymers are very bright, and have color tunability — obviously a useful property when assembled as pixels to form images. There are, moreover, no viewing-angle problems as with liquid crystals. Other applications include UV lithography; and some polymers make great stealth antennas. They can basically do the same things as silicone semiconductors. And yes, transistors can be made from them; so can photovoltaic cells.
The relatively recent discovery of carbon nanotubes (a development about which we have had two previous programs) has created a whole new field of opportunities in material science and nanotechnology. These tiny bits of micro-macaroni have twenty times the strength of steel with a density half that of aluminum (1.33 SpG). They could, for example, become miniscule gas cylinders. But when subjected to the kind of alignment and micropatterning described above they can become chemical/ biosensors, field emitters for panel displays, or even miniscule circuitry that could serve as memory corpuscles for very compact computer packages. Dr. Dai has also worked out techniques for depositing concentric multi-layers of conducting polymers on individual nanotube surfaces, or chemically grafting polymer chains onto these surfaces. Wow!
Finally, for the first time in 2003, PLEASE ZAP your RESERVATIONS (or regrets) by Thursday PM, January 23: