**Akron Phy ****sics Club**

Archive 2014

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Newsletter

Meeting Announcement: MONDAY, January 24, 2014 - TANGIER, 6:00 PM

**Dr. Matthew Shawkey**, University of Akron

will be speaking on:

**Optics and evolution of plumage color in birds and other dinosaurs**

**Abstract: **

Birds have a tremendous diversity of colors, many of which are produced not by pigment deposition but by light interference and scattering effects from nanometer-scaled, highly organized tissues within feathers. Some of the most famous examples include the brilliant blues and "eye spot" tails of peacocks and the flashy reds and greens of hummingbirds. Our lab group explores how these colors are produced, how they grow in the developing feather and how they change over evolutionary time. I will discuss these topics, as well as recent evidence for their presence very early in the evolution of birds from meat-eating dinosaurs in the same group as T. rex and Velociraptor.

The Speaker:

Dr. Shawkey grew up in Northern Virginia, received his undergraduate degree in Neurobiology at Wesleyan University, Master's in conservation biology at University of South Florida, then became fascinated with animal colors as a Ph.D. student at Auburn. He continued work as a post-doc at Berkeley, then joined the University of Akron faculty in the Biology/Integrated Bioscience Department in

Minutes, January 24, 2014

Chair von Meerwall called the meeting to order. Bill Dunn introduced Arnetta Stover and his son Steve Dunn.

Dr. Dan Galehouse, Treasurer reported that we had 19 paid dinners, for a gain of $2, resulting in a balance of $351.45 in our treasury.

Dr. Charles Lavan reviewed our upcoming meetings. After the February meeting, Dr. Peter Hoekje from Baldwin Wallace University will be speaking on the topic of Music, Flutes and Physics on March 25. On the 22nd of April, Dr. Peifang Tian of John Carroll University will speak on Imaging 3-D Spatiotemporal Hemodynamics, and at our 'May meeting' on June 3, Dr. Jay Reynolds will speak on the DAWN Mission to Asteroid VESTA.

Erdman thanked those of the group who judged the Akron Science Fair last Saturday, and mentioned that he is working on a venue to recognize the recipients of the Charles W. Wilson Scholarship in Physics, with the university of Akron and Charlie's family. See last meeting's minutes, or contact Erdman if you are interested in donating to this Scholarship Fund.

Chair von Meerwall announced that the Physics Department at the University of Akron is thinking of starting an Advancement Council. If anyone or any local company is interested in perhaps participating in this effort, contact Erdman at This email address is being protected from spambots. You need JavaScript enabled to view it.; the input will be forwarded. This advisory council will consist of local organizations and STEM individuals who will advise the Department of Physics on how to conduct their operations better, interface with students and faculty, help determine how the Department can provide better service to the community, etc.

The Chair introduced Dr. Matthew Shawkey: He is an Associate Professor at the University of Akron. His undergraduate degree was in Neurobiology at Wesleyan University, his Master's in conservation biology at University of South Florida, then he became fascinated with animal colors as a Ph.D. student at Auburn. He continued work as a post-doc at Berkeley, then joined the University of Akron faculty in the Biology/Integrated Biosciences Department in 2008.

NOTES ON THE PRESENTATION by Dr. Shawkey:

Color can affect human's moods and state of mind. In animals, it can help certain species blend into their background or stand out in an attempt to mate. These colors have been studied, but there is not a lot of work on the mechanisms that produce colors in non-human animals. The two primary mechanisms for color production are pigmentation, which typically involves reflections of wavelengths within the visible region, and structural colors, which are produced by constructive interference of light by materials having periodically varying refractive indices. Their work focuses on the latter, which has a much wider spectrum of "colors", from ultraviolet to near infrared wavelengths. Using a Mallard as an example, a plumage patch contains certain kinds of feathers, which are visible to the naked eye. The feathers contain barbs on the order of 1mm size, which in turn consist of barbules on the scale of hundreds of microns. Inside of these are keratin and nanostructures consisting of nanoscale stacks of melanosomes which have an associated pigment color. The melanosomes are developed in melanocytes.

As light travels into a bird feather, it passes through air [Refractive Index 1.0], then through the keratin layer [Refractive Index 1.54] in the barbules, and then into the melanin layer [Refractive Index 2.0] formed by the melanosomes. At each interface, due to the difference in Refractive Index, some light is reflected and some proceeds to the next layer at a different angle of incidence [that is, it is "bent" or refracted], where a portion of it is again reflected and another portion again refracted. The reflections are again refracted as they return to the medium from which they came, causing constructive and destructive interference among the light waves, amplifying some colors, attenuating others. This is the same effect that makes oil sheens and soap bubbles appear in rainbow colors. The above is a description of a 1-dimensionsal structural colors, as in a bird of paradise. In a Peacock, and other animals, this happens in two dimensions, creating a checkerboard pattern of different materials in a plane. If the checkerboard varies with location in the 3rd dimension, a 3-D checkerboard pattern is created, as in the [local] bluebird colors.

Using the 1-D nanostructure as a model, the impact of radius and spacing [wide spacing is called more open] can be determined. Tightly packed structures [less open] exhibit duller colors, open structures are brighter. Some melanosomes evolved into hollow structures. These can be close packed but also exhibit bright colors. Others evolved into flattened melanosomes that are rectangular in shape. Some are hollow, some solid. As the species evolved, it was found that they evolve toward more complexity [hollow, rectangular, solid, etc.]. There is no evolution back toward the simpler structures. So the more evolved species have a wider variety of colors. They also developed into a wider variety of anatomical structures and species, including dinosaurs.

A commonality of micron-sized structures was observed in various species of birds up to 60 million years old, and squid ink. This led to comparison of melanosomes, and ultimately to predicted colors of early bird species, based on similarities of melanosomes. In the Archaeopteryx, melanosomes were analyzed as being primarily black and white colors. It was also found that certain melanosomes were associated with stronger structures in the wings. This led to a more complete picture of bird evolution.

We thanked the speaker, and he answered a few questions, including how chameleons change their color: Physiologically, the spacing of chameleon melanosomes can be changed, giving them an ability to adapt color to their surroundings. Squids can do this very rapidly. He also mentioned that in order to be able to examine feathers on dinosaurs, the feathers had to be covered in dirt very soon after death. If they are, melanosomes can be can be examined millennia later.

Bob Erdman, Secretary

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Newsletter

Meeting Announcement: MONDAY, February 24, 2014 - TANGIER, 6:00 PM

**Dr. Nathan Ida**, Distinguished Professor of Electrical and Computer Engineering, University of Akron

will be speaking on:

**Computational Electromagnetics - Models and Applications**

**Abstract: **

The talk focuses on large-scale computation of electromagnetic fields with particular application to models in eddy current test in nuclear power plants. The accuracy needed requires a volumetric model – finite elements in this case – in conjunction with surface impedance boundary conditions to reduce the model to a manageable size. Results from work on the French system of nuclear power plant steam generators highlighting needs and available solutions are given as well some as other related results in modeling for corrosion research.

**The Speaker: **

Dr. Nathan Ida is currently a Distinguished Professor of Electrical and Computer Engineering at the University of Akron, Akron, OH. He teaches electromagnetics, antenna theory, electromagnetic compatibility, sensing and actuation, and computational methods. His current research interests include numerical modeling of electromagnetic fields, electromagnetic wave propagation, theoretical issues in computation, nondestructive testing of materials at low and microwave frequencies as well as in communications, especially in low-power remote control and wireless sensing. He has published extensively on electromagnetic field computation, parallel, and vector algorithms and computation, nondestructive testing of materials, surface impedance boundary conditions, and others. He is the author or coauthor of six books.

Dr. Ida is a Fellow of the IEEE, of the American Society of Nondestructive Testing and of the Applied Computational Electromagnetics Society.

Join us for this meeting on an interesting application of computational modeling to an important set of problems.

Minutes, February 24, 2014

Mark Murad, a visiting student at the University Akron was introduced by Chair von Meerwall. Jonah Kiszenberg has been unable to attend the last few meetings due to long hours at work, but sends his regards and hopes to attend some meetings in the future. Jack Gieck was planning to come, but had to stay at home to assist his wife with some medical issues.

Last month's meeting was cancelled, and we hope everyone got word that the meeting was cancelled, the first such cancellation in the Club’s 22-year history, basically due to weather conditions causing multiple problems. We plan to issue an email indicating cancellation should this situation arise again, counting on everyone to read their email. Please let the Secretary know if you would like a telephone call in addition. Chair von Meerwall presented this policy and asked for comments or suggestions. No one had objection to the policy, so we will operate in this manner.

Dan Galehouse presented the Treasurer's Report: We had $28 revenues at this meeting less $36 expenses for dinners for a student and the speaker, for a net $8 loss, reducing the treasury from $487.45 to $479.17. Cash on hand agrees with this number.

Secretary Erdman reviewed the remaining programs for this year, in the absence of Program Chair Lavan, who is out of town: After the March meeting in this announcement, Toni Colozza of NASA Glenn will discuss planetary exploration using buoyant flight vehicles [balloons] on April 28, and on June 2 Mark Taylor of Hiram College will present a discussion on statistical mechanics. Melana Espanol, who was to talk on Deblurring Images with Mathematical Models in January, is discussing a schedule on which to present this on the club's 2014-2015 season with Program Director Lavan.

Chair von Meerwall introduced our speaker for the evening: Dr. Nathan Ida got his BSEE and MSEE at Ben Gurion University in Israel, and his doctorate from Colorado State University. He is currently a Distinguished Professor of Electrical and Computer Engineering at the University of Akron, Akron, OH. He teaches electromagnetics, antenna theory, electromagnetic compatibility, sensing and actuation, and computational methods. Dr. Ida is a Fellow of the IEEE, of the American Society of Nondestructive Testing and of the Applied Computational Electromagnetics Society.

NOTES Dr. IDA'S PRESENTATION [with correction]:

The talk will focus on finite element analysis and the ideas involved in applying this technique to electromagnetics and related testing. The process is to start with a physical problem, simplify it so it can be modeled on computer, then apply boundary conditions. This discussion will be limited to frequency domain. The basic method is to divide a space into finite elements, develop a numerical model corresponding to the physical model using one of many numerical methods, solve the problem within each element, the re-assemble and display the complete system.

A finite element is a small surface [if 2-dimensional space] or volume [if 3-dimensional space] with scalar values assigned to nodes, and vector values assigned to edges. A solution is formulated within the element – usually in simple polynomial form in terms of the nodes and vectors for edge values. Edge/node values then become the degrees of freedom to solve for. A formulation of the physical problem is formed (usually in terms of energy using either a variational method or a least squares method). The function obtained in the formulation is minimized over each element for each variable. The assembly of all elements results in a system of equations, which are solved using a convenient method for the unknowns.

Dr. Ida gave an example of a formulation of the problem based on Maxwell's equations, in a general solution domain which includes conducting and non-conducting media, magnetic and non-magnetic media. He showed how the elemental matrices are obtained either through variational means or weighted residuals, and how boundary conditions are applied. The contributions from each element are entered into the system of equations, resulting in a driving function, for example charge in the example used, but it could be current or another parameter. In answer to a question, Dr. Ida pointed out that this is solution under a set of assumptions. If the assumptions are suspect, smaller elements or adaptive equations can be used to accommodate a wider set of assumptions.

Dr. Ida illustrated this by describing some work he did in France a few years ago. The problem was to develop a formulation called Code Caramel for the French power company. A variational means was used to describe the energy function. This was a 3-dimensional problem, using tetrahedral functions, with scalars for the nodes, vectors for the edges. This was a low-frequency model, thus no radiation is involved. In setting the boundary conditions for the system of equations it was important to keep the total matrix small enough to be calculated. This was done by introducing a surface impedance boundary condition, which reduces the equations at the conductor surface to one dimension, essentially the skin effect parameter.

In France, about 80% of power is generated by nuclear power plants. The primary fluid is at a high temperature [600C, 1200psi] and is radioactive. The secondary fluid is non-radioactive water which is to be turned into steam. The structure consists of hundreds of 19mm diameter stainless steel tubes supported by 25-30mm carbon steel plates. There is a 0.04mm gap between the hole in the plates and the outside of the tube. Corrosive materials build up in the gap and can crush the tubes, creating a radioactive leak. Eddy-current probes are used to measure the amount of material built up and any tube deformation. Since there is high cost to shut down the plant and monitor the amount of build-up, a predictive modeling process was to be developed, so that shut-down was only done when needed. The composition of the buildup had to be modeled: About 100,000 degrees of freedom were involved; Calculation time exceeded one week. The program was discontinued, due to the time to model. Years later, a more sophisticated reactor design and modeling was again tried. The initial design had 1,000,000 elements, 30-80 points are required on each eddy current curve, and each point required 21 minutes hours to solve. By reducing the size of the lattice and using the simplifying surface impedance boundary conditions, these can be reduced to 400,000 elements, and each curve could be done in about 3 minutes.

Another example was explored in monitoring latex thickness on fabric using strip line simulation. Modeling was useful to minimize disruption where a splice was made to a new sheet of material.

Bob Erdman, Secretary

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Newsletter

Meeting Announcement: MONDAY, March 24, 2014 - TANGIER, 6:00 PM

**Dr. Stefan Forcey**, Professor of Mathematics, University of Akron

will be speaking on:

**Seeing in Four dimensions**

**Abstract:**

We have just been hearing lots about the gravity-wave signature of early inflation of the universe. The mental picture of a small early universe that is (maybe) a 3-dimensional sphere is usually achieved by making analogies to the surface of a 2-dimensional sphere. In this talk I’ll show a series of pictures and models of things happening in 3d with different connectivity than we are used to, in 2d but embedded in 4d, and if time permits in 4d versions of polyhedrons.

**The Speaker: **

Currently professor of math at University of Akron. PhD. from Va Tech. Lived in VA and Tennessee until we moved to Akron in 2010, but I have roots in upstate NY and lots of family in Central PA. I research mostly in combinatorics and topology: the first is about how we can build complicated structure by using simple blocks with simple rules; the second is about the shape of space.

Join us for this interesting meeting.

Minutes, March 24, 2014

Leah Forcey, the Speaker's wife, was introduced by Chair von Meerwall.

Dan Galehouse, Treasurer reported that tonight 14 paid meals brought in $28; two meals for guests cost $36, and our annual dues to ACESS cost $10, for a net loss of $18. Thus our balance was reduced from $479.45 to $461.45.

Program Chair Lavan thanked Dr. Forcey for agreeing to speak on very short notice. Dr. Tolley, who was to speak at this meeting was still in Toronto and could not get away. He is now scheduled to speak in October 2014. Chair Lavan was on an interesting trip to Clary Peak north of Fairbanks Alaska. Hans Christian Nielson gave Dr. Lavan a copy of slides depicting various aurora effects. He will consider presenting these as a program in November. In September Dr. Espanola, who was to speak in January will present her original talk.

The club is looking for volunteer officers for the coming year. If you enjoy attending the meetings and can attend often, or know of someone who may be interested, please contact Chair von Meerwall, or the email address listed above. This could be a full position, or an understudy for a position, working with the person now in that position at first. We will vote on officers at our next meeting.

The Chair von Meerwall introduced the speaker: Dr. Stefan Forcey was trained in mathematics and computer science at Virginia Tech and got his Masters and Doctorate in both areas from there. He was at the Tennessee State University, and then came to the University of Akron in the Mathematics Department in 2010, where he is an Assistant Professor. He is a topologist, numerical analyst and simulator and wrote his thesis on Loop Spaces in Higher-dimensional Iterated Enrichment.

NOTES ON DR. FORCEY'S PRESENTATION:

The title of his Talk is Seeing in Four Dimensions. The disclaimer is that people cannot do this. This will be about "tricks" that help us envision a 4th spatial dimension. He started with a solid sphere. The boundary of a solid sphere is an empty sphere, represented by the equation x^2+y^2+z^2=K which can be inscribed in a cube. If we place a dot in the center of each of the 6 faces of a cube and connect these dots, a tetrahedron is formed by the dots. Subtracting one dimension from a cube yields a square, which is one square surface [edge, boundary] of a cube. Subtracting one more dimension yields a line, which is the edge or boundary of a square.

Schlegel diagrams are formed by looking through one face of a polyhedron and viewing the other faces and edges as seen "through" the first, such as looking at cube through the top face, wherein you would see the bottom face as a smaller square, connected by 4 lines to each corner of the larger [top face] square. In a similar manner, the Schlegel diagram of a 4-dimensional cube would be a smaller cube inside a larger one, with all 8 corners connected. Also the boundary of a 4-dimensional sphere [x^{2}+y^{2}+z^{2}+t^{2}=K] would be a 3-dimensional solid sphere.

Dr. Forcey then related this thinking to a mobius strip, a 2-dimensional strip which is formed into a 3-dimensional object. One higher-order extrapolation of this would be a torus [think inner tube] which forms a "Klein bottle" in 4 dimensions. Like the mobius strip, if you follow one side of the tube, you pass the starting point on the opposite side, and then if you keep on going, end up at the original starting point; thus it only has one boundary. He passed around a glass model of a Klein bottle.

Another way to view a 4th dimension is to consider "gluing boundaries": For example, if the long edges of a long rectangular sheet of paper are glued together, it forms a long tube. If the ends of the tube are glued together, a torus is formed. Using this thinking one can think about gluing boundaries of 3-dimensional objects. It is interesting to note that above 4 dimensions, things collapse, so that 4 dimensions has the most 3-dimensional boundaries, thus can be considered the most interesting space.

Discussion questions involved the question of are we familiar with 3 physical dimensions thus it seems the most natural--is that peculiar to human orientation? Also what happens if the edges of a mobius strip are glued together? [the Klein bottle is one result], and the relationship between multi-dimensional tensors and multi-dimensional space [they are mathematically similar, but as hard to envision multi-dimensional tensors as it is to envision multi-dimensional space]. We thanked the speaker with a round of applause.

Annotated complete slides of Dr. Forcey's talk, including representations of Klein bottles, can be seen at http://www.math.uakron.edu/~sf34/#perm. Click on Seeing in 4 Dimensions. These notes only cover the main points of his talk.

Bob Erdman

Akron Physics Club Secretary

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Newsletter

Meeting Announcement: MONDAY, April 28, 2014 - TANGIER, 6:00 PM

**Dr. Anthony Colozza**, NASA Glen Research Center

will be speaking on:

**Planetary Exploration with Buoyant Flight Vehicles**

**Abstract:**

This presentation addresses the history, challenges and future concepts of robotic flight vehicles to operate within the atmospheres of other planets. The science value of flight vehicles and their unique capabilities as compared to satellites and landers/rovers is also addressed. The majority of the past and present designs focus on Mars, Venus and Titan as locations that would be suitable for atmospheric flight vehicles both aircraft and airships.

**The Speaker:**

Anthony Colozza, is a research engineer working for Vantage Partners at the NASA Glenn Research Center. This work has primarily centered on the design and analysis of propulsion, power and thermal systems for spacecraft and planetary vehicles. He has over 23 years experience and has published over 90 documents including NASA reports, conference and journal papers and book chapters. He has been part of NASA Glenn’s COMPASS design team for the past 6 years performing the thermal and environmental analysis and design for various spacecraft missions. He was also PI on 2 NIAC phase I and II studies looking at novel flight vehicles for the exploration of Mars and Venus. Additional areas of interest include high altitude aircraft and airship design and planetary atmospheric flight vehicle design.

Join us for this excellent evening on a fascinating subject presented by an expert with many years of experience in the area.

Minutes, April 28, 2014

Chair von Meerwall welcomed Jack Gieck, Co-founder and Mike Piekarski who has been in Florida.

Dan Galehouse, Treasurer reported that there were 22 paid meals plus one IOU; 23 x $20 = $460. The meal charges were 24 x $18 = $432 but being short of change, the Tangier accepted $430. There is a net gain of $460 - $430 = $30 bringing the PP box up from $461.45 to $491.45.

The cash on hand agrees.

Program Chair Lavan talked about the June 2 program [above] and tentative programs for next year: In September Dr. Espanola, who was to speak in January will present her original talk on optical deblurring. Dr. Tolley is now scheduled to speak in October 2014 on cosmology. In November Charles Lavan will make a presentation on auroras that he heard about on his trip to Clary Peak north of Fairbanks Alaska.

The club is looking still looking for volunteer officers for the coming year. Chair von Meerwall indicated this could be a full position, or an understudy for a position, working with the person now in that position at first. If we get no new volunteers, we will be forced to continue with the present officers. We will vote on officers at our next meeting.

The Chair von Meerwall introduced the speaker: Anthony Colozza is a research Engineer at NASA Glenn involved in design of spacecraft vehicles, centering on thermal and propulsion systems. He has been working in this field for 23 years and published over 90 papers. He also has an interest in high-altitude planes and airship design.

NOTES ON THE PRESENTATION:

NASA has designed rovers, landers and satellites. Each has its own niche and purposes and is good at accomplishing its purpose. Satellites have been flown to Jupiter, Venus, Mars, and Saturn, mainly with a mission of remote sensing and global mapping of the body to which they are sent. Landers were sent to Venus, Mars and to Titan. These typically last a short time, explore the very local environment where they land, and some search for evidence of life. Rovers have all been to Mars. They can move around up to a few hundred meters from the landing site. If a vehicle that flies around the planet could be implemented, it would cover a region of the planet or moon that is much larger than the area covered by a rover, and in more detail that a satellite can provide, with the ability to view vertical surface features from different angles.

Two types of cameras on an aircraft could be used; one for context of the region in which more detailed pictures are taken by a second camera, down to the scale of a few cm. An aircraft could sample the atmosphere at various altitudes for gases and characteristics of dust storms. Various wavelengths of light including near infra-red could be used. Magnetic fields can be mapped more precisely than from a satellite.

There are some serious challenges to designing an aircraft for other planets or moons: The atmosphere is seriously different than earth, without free oxygen, at very different atmospheric pressures, from very low on Mars [equivalent to about 100,000 feet on earth] to 92 bars on Venus. Communication cannot be in real time from earth, fuel has to provided, there is no person there to assemble or deploy the aircraft, and of course weight must be minimized. All the data must be obtained and initially transmitted in a few minutes to few hours, the flight duration. Is it often not possible to land and take off again, for example stall speed on Mars is 250 mph, making it virtually impossible to land a plane due to the rocky irregular surface. Very different engines would need to be developed to power the aircraft. NASA has considered a wide variety of engines from modified traditional engines on earth to radical new types, such as burning titanium in the hydrogen atmosphere on Titan. Gliders were also considered, but the low air pressure is difficult to glide in, the glider would descend very rapidly, and it would be difficult to steer.

In 1999, a rocket plane that would fly on Mars was considered. It would have been on the Mars Micro Mission, where the European Space Agency would provide a small free space on a rocket to Mars. NASA explored the possibility of a small plane to fit in the space allotted. Studies showed that it could fly for 20 minutes and cost $60 to $100 million. The program was then cancelled. In 2007 NASA Langley did a serious design of the SCOUT rocket plane. It was proposed as an alternative to the Phoenix Lander ultimately used for the Discovery mission. A drop test was done on the SCOUT from 100,000 feet over the State of Washington. It flew for a few hours.

Analysis was done on possible aircraft for use on Venus. There is a sulfuric acid cloud layer at an altitude of about 40-60km above the surface which has at a temperature of about 455 degrees C. Very high winds exist above this layer; visibility is very low below it. Solar planes were designed for flight above the cloud layer. They had to go faster than the high winds above the clouds. The concept considered was a plane that would communicate with and control a relatively incapable rover vehicle on the surface, and also communicate with a satellite orbiting earth, which would send data back to earth. This analysis will help define what technologies and capabilities would be needed to explore Venus. The rover would require cooling due to the high surface temperature. An airship was also considered for use near the surface of Venus. More information is available on this in NASA document NASA CR-2012-217665.

Titan has a lot of atmosphere, 94% Nitrogen, 6% Methane. Wind speed is low, surface temperature 94K. Airships were considered for use there that would operate near the surface at altitudes of a few km.

The last categories of planets are the gas giants. Little work has been done on these. Only the outer surface can be easily observed. The density of gas in Jupiter is much higher than any pressures on earth, including at the bottom of the ocean. Since there are no surface features, a balloon may be suitable for these even though the direction is not controllable.

Further Ideas: Inflatable craft with very large wing spans, possibly powered by solar cells, could be considered for use in thin atmospheres such as Mars. Using electro-active polymers powered by solar cells, it may be possible to build large aircraft that flap their wings like a bird. The needed materials have been around for about 10 years, and were initially made as a material for artificial muscles. The material can lift about 10 times its weight, and has response up to about 250 Hz. Water is required to make it work. Another idea is a craft that flies like a bug, hovering by means of very fast wing flapping, not requiring forward speed. This is based on vortex shedding. Steering can be done by shedding vortex early or late. Flight time on one load of fuel is about 15 minutes, but they can be refueled from a rover.

The biggest limitation to exploring some of these ideas is the relative priority and potential for wealth creation of space programs. Communications satellites are an example of wealth creation from these technologies.

Many questions related to these topics were asked during the presentation. We thanked the speaker with a round of applause.

Bob Erdman, Secretary

Newsletter

Meeting Announcement: June 22, 2014 - TANGIER, 6:00 PM

**Dr. Mark Taylor**, Hiram College

will be speaking on:

**Statistical Mechanics**

Minutes, June 22, 2014

Dr. Mark Taylor, our Speaker, introduced Students from Hiram who work with him on projects mentioned in the presentation: Samip Basnet from Napal, Ryogo Suzuki from Japan, and Su Latt from Myanmar [formerly known as Burma].

Sergei Lyuksyutov introduced two students from Akron Physics Department: Jeff McCausland and Rasika Dahanayake. [Sajeevi Withanage came later].

Mark Murad brought Thomas Gilbrid to the meeting.

Program Chair Lavan overviewed talks for the first part of next year: In September Dr. Espanola, who was to speak in January will present her original talk. Dr. Tolley, who was to speak earlier, is expected to present a talk on some aspect of cosmology in October. Charles Lavan will present Slides of auroras which he observed north of Fairbanks Alaska.

Dave Sours, kindly substituting for Dan Galehouse, Treasurer, reported that tonight 15 paid meals brought in $300; meal expenses were $378, leaving a balance of about $411 in the treasury.

There were no new volunteers for officers for the coming year. There being no objections, all officers will remain in place. If you enjoy attending the meetings and can attend often, or know of someone who may be interested, please contact Chair von Meerwall, or the email address listed above. This could be a full position, or an understudy for a position, working with the person now in that position at first. In particular, the Webmaster could probably use some help.

The Chair von Meerwall introduced the speaker: Dr. Mark Taylor from Hiram College. He has a Bachelor of Physics from Massachusetts Institute of Technology in 1982, and a Ph.D. from Brandeis University in 1991. He has been at Hiram for 14 years.

NOTES ON DR. TAYLOR'S PRESENTATION:

Dr. Taylor referenced his many collaborators, at Hiram, some of whom are in attendance, University of Akron, and in Halle Germany. Hiram is an undergraduate institution where students are actively involved in research projects. His talk concerns boundaries between phases of single-polymer chains. Transitions between these phases can take many forms, such as coil-globule transitions, or transitions to a small crystals, or absorption-desorption transitions. Some of these transitions can be used to make smart materials, among other uses. The work he does is sufficiently large scale that classical, not quantum mechanics are involved, since the work involves molecules, not individual atoms or sub-atomic particles. The phase transitions take place in a dense solvent. Statistical mechanics and models are used for this work.

Single-polymer chains are a repetitive series of a sequence of atoms. Each group of atoms [monomer] in the sequence can be treated as a "bead"; these are chained together to make a "pearl necklace" [polymer]. The monomers will not overlap, but there is a larger sphere around each in which interactions with other monomers occur. If the polymer configuration is a long chain stretched out, there will be no interactions since no monomers are close enough to another that is not its neighbor in the chain. If this chain folds up on itself into a globular cluster, there are a maximum number of interactions, representing a minimal energy state. A partition function can be generated which describes the system as a function of temperature. For this case, the system has a discrete energy spectrum; the energy levels are determined by the number of interactions between monomers, n, and the energies are n*E where E is the minimum quantum energy. The partition function for this is a polynomial in e^{(-E/kT)}, with the coefficient of each term being the density of states [number of configurations which can occur] at energy level n. In a folded configuration, like a crystal or globular cluster, there are few allowable states, and the density of states is low. In an open structure, there are many configurations with the same energy, and the density of states is high.

Two ways of characterizing polynomials are by their roots y=(X-R1)(X-R2)(..., or by their coefficients y=Co+C1X^{1}+C2X^{2}+.... Coefficients were discussed above. Roots can be real or imaginary [the solution to X^{2}+1=0 is x = + i ]. Complex roots are plotted on the complex plane with the vertical axis being roots involving i [imaginary numbers], and the horizontal axis being real roots. Some polynomials have both real and imaginary roots. Yang and Lee proposed that if there are no phase transitions, there are no real roots. If there are phase transitions, real roots occur at the transitions, and there are no roots in the region of a given phase. This was tested on the Ising Model, a magnetic system with a partition function that can be exactly determined. However, for most systems, the partition function calculation is extremely daunting or impossible. Thus the Yang-Lee method has not been extensively used in practice, but the availability of more powerful computing hardware and software has renewed interest in this theory.

Dr. Taylor uses the Wang-Landau algorithm to solving polynomials related to polymer chains. This is basically a modified monte-carlo "guess and check" method, with non-traditional acceptance criteria. In simulation with n=32 [32 interactions between monomers], by substituting a new end monomer, a variety of configurations can be made; density of states in such a simulation varies by 88 orders of magnitude. Dr. Taylor showed an example of a 16-interaction simulation using Mathematica to determine 34 or the 38 roots in the solution. Using chains of 256 length, he showed specific heat results with very repeatable results clearly indicating phase transitions where the roots approach are on the real axis.

A similar method can be used to determine phase transitions in absorption-desorption phase changes by varying the exponents, again with good correlation between roots approaching the real axis at phase transitions.

Another area of exploration is looking at bonding angles first when monomers are tangent, and then when they are spaced closer than the diameter, forming rigid chains. In this case, the persistent shape that results is a helix. This is an example of the possibility that there are some basic physical properties that are fundamental to various chemical and structural properties. Dr. Taylor's work he noted assumes similar monomers, thus it cannot directly be applied to polymers involving a variety of monomers.

There were a few questions on specific methods used, and future extensions of this work. We thanked the speaker with a round of applause.

WE WILL NEXT MEET ON SEPTEMBER 22. The speaker will Dr. Espanol, as mentioned above. As usual, we will meet at The Tangier. You will receive an announcement in mid-September.

For your information, websites and some events for other ACESS technical societies in the Akron area may be viewed at: http://www/cs/kent.edu/~batcher/ACESS.html.

Societies have limited or no activities in the summer, so this is more useful during the academic year.

Bob Erdman, Secretary

Newsletter

Meeting Announcement: MONDAY, September 22, 2014 - TANGIER, 6:00 PM

**Dr. Malena Ines Espanol**, Applied Math, University of Akron

will be speaking on:

**Deblurring Images with Mathematical Models**

**Abstract: **

When we use a camera, we want the recorded image to be an accurate representation of the scene that we see. However, in some situations such as photographing a moving object, we obtain a blurred image. In image deblurring, we seek to recover the original, sharp image by using a mathematical model of the blurring process. The key issue is that some information on the lost details is indeed present in the blurred image, but this information is hidden and can only be recovered if we know the details of the blurring process. Unfortunately there is no hope that we can recover the original image exactly due to various unavoidable errors in the recorded image. One of the challenges of image deblurring is to develop efficient and reliable algorithms for recovering as much information as possible from the given data. In this talk, we will see a brief introduction to the basic image deblurring problem and some mathematical models that deal with it.

**The Speaker: **

Dr. Malena Espanol is an assistant professor of applied mathematics at The University of Akron. Prior to joining UA, Dr. Espanol was a postdoctoral scholar at the California Institute of Technology where she was a member of the Computational Solid Mechanics Group. She obtained her M.S. and Ph.D. in Mathematics from Tufts University and her Bachelor degree in Mathematics from the University of Buenos Aires, Argentina. Her research consists of designing and analyzing numerical methods for problems arising in solid mechanics, materials science, and image processing.

Minutes, September 22, 2014

Chair von Meerwall commented that Jack Gieck, Co-founder, and John Kirzensberg, Webmaster, both planned to be here but regrettably could not make it. Joe Gorse and students from Universities of Akron and Kent State were introduced.

Charles Lavan and Chair von Meerwall have initiated some contacts regarding publicity for our meetings. Charles spoke with Jeff St. Clair of WKSU who hosts a science exploration program Monday mornings. He plans to join us for a meeting, interview the speaker and mention the Physics Club on the air.

Charles Lavan reviewed forthcoming programs for the year, which are listed in the attached Program Agenda and cover a wide variety of topics. Updates and changes will be in the notes of our meetings during the year. You may want to keep this list. We thanked Charles for his excellent work in putting together such an interesting program for the year. He will be visiting the Aurora research center in Alaska again in 2015 and hopes to present a talk on this work about a year from now.

Dan Galehouse, Treasurer reported there are 17 paid attendees tonight. We owe $56 net for the student and speaker dinners. When Dan gets the treasury box, which was inadvertently forgotten for tonight's meeting, he will announce the total.

Secretary Erdman mentioned that as part of our support for local high school science fairs, some members may wish to talk with students about their projects at a speed mentoring session on the morning of October 18 at Hudson High School, or judge the STEM Project Fair. More detail is at NEOHSTEM.org. To sign up: https://www.neohstem.org/JudgeSignup.php?signupPage=46

Chair von Meerwall introduced the speaker: Dr. Malena Espanol was to speak last January at a meeting that was cancelled by snow. She did her undergraduate work in mathematics at the University of Buenos Aires, and her Masters and PhD in mathematics at tufts University. She was a Post-Doc at Cal Tech for some years, and is now an Assistant Professor in Mathematics at the University of Akron.

NOTES ON THE DEBLURRING PRESENTATION BY DR. ESPANOL:

This is about deblurring digital images using mathematical models. This can be done with microscope and telescope images, where the lens creates some level of blurring, medical digital images, or photographic digital images. An image may be mathematically considered a large matrix or a long vector. The essential problem is to determine the true image, given a blurred or noisy image, represented by this vector. The blurred image includes the effects of perturbations not present in the true image.

A way of doing this known as regularization is to consider each element of the vector the sum a perturbation and a linear approximation y=Ax. The perturbation is of the form (l^{2})*(Lx) where L is an operator on the vector, such as the identity operator, a derivative operator, or a Laplacian operator. l is a parameter that has a big impact on the resulting data. Examples were given where with a low l the image was virtually undetectable, but with l=1 it was an excellent representation of the image. l can be theoretically calculated empirically to minimize the error or learned from "training data" consisting of a few to a few hundred observations of the blurred image. Since the perturbations are random, more training observations will result in lower errors. Data was shown indicating the errors are low and not reduced greatly beyond observing 10 sets of training data.

Examples were given wherein they looked at 200 images of 5 different MRI pictures [a vector with 1000 elements] to develop l, then tested this value on 200 different images of the same 5 MRI patterns, with the result there was a very little difference between the original and reconstructed images. Data was also shown from applying different operators (L) and a combination of 4 operators. This same multivariable technique was applied to analysis of MRI images to determine whether patients have a disease. Results were that classification was effective by looking at a few parameters of the observed features.

Questions included the application to telescopes, the use of Fourier transforms and relationship of the A vector to transfer functions used in electric engineering, how multiple L operators were chosen, and whether graphical processors would be useful. We thanked the speaker with a round of applause.

Bob Erdman, Secretary

Newsletter

Meeting Announcement: MONDAY, October 27, 2014 - TANGIER, 6:00 PM

**Dr. Mark Manley**, Department of Physics, Kent State University

will be speaking on:

**Partial-Wave Analyses as a Method for Studying Baryon Spectroscopy **

**Abstract: **

A single polymer chain can undergo a series of conformational transitions analogous to the phase transitions exhibited by bulk materials. Our recent work studies such single chain phase transitions using the Wang-Landau (WL) algorithm, a Monte Carlo simulation technique providing a direct computation of the density of states (and thus the partition function) of a many-body system. The partition function encodes all thermodynamic information about a system, and thus, its construction allows for an efficient determination of phase behavior. Here we describe the application of the WL approach to a number of coarse-grained model polymers. We study single chain folding and adsorption transitions in these systems using canonical and micro-canonical thermodynamics and through analysis of partition function zeros. In the latter case, the distribution of these zeros in the complex plane provides distinctive signatures for different transitions. With increasing chain length these zeros pinch down towards the positive real axis, dividing this axis into distinct regions or phases, in accord with the theory of Yang and Lee. Using finite size scaling theory for the leading partition function zeros we can locate phase transition in the thermodynamic limit and determine critical exponents.

**The Speaker: **

Mark Manley earned a B.S. degree in physics from Northeast Louisiana University (now the University of Louisiana at Monroe) in 1975. Afterwards, he began graduate school at the University of Wyoming. His Ph.D. research in medium-energy nuclear physics was performed at Los Alamos National Laboratory, where he resided from 1978 to 1981. After earning his Ph.D. in 1981, he had postdoctoral appointments at Virginia Tech (1981 to 1984) and Lawrence Livermore National Laboratory (1984 to 1986). In 1986, he started his career in the Department of Physics at Kent State University. He has been a full professor there since 1997. For the past 10 years, his experimental research has been performed in Mainz, Germany as part of the Crystal Ball and A2 Collaborations. He currently has about 120 publications in refereed physics journals and has presented over 30 invited talks at scientific meetings worldwide.

Minutes, October 27, 2014

Chair von Meerwall plans to invite Mr. Dowling from the Akron Beacon Journal to one of our future meetings, possibly the November 24 meeting on Cosmology presented by Dr. Tolley, possibly another meeting. Other talks are as planned. Jeff St. Clair, of WKSU may join us in March, interview Dr. Steinmetz, the speaker, and mention the Club on WKSU.

Treasurer Galehouse reported that he again has the plastic box in his possession, and the contents appear to be in order. For this meeting, we have 12 paid attendees and we have two guests for dinner, for a net loss of $12. The balance is now $343.45.

Secretary Erdman thanked Mr. Aung from our group who attended the brainstorming session for the Hudson Project fair last Saturday. It was well attended and the high school students benefited from the discussions.

Chair von Meerwall introduced the speaker: Prof. Mark Manley earned a B.S. degree in physics from Northeast Louisiana University in 1975. Afterwards, he began graduate work at the University of Wyoming. His Ph.D. research in medium-energy nuclear physics was performed at Los Alamos National Laboratory, where he resided from 1978 to 1981. After earning his Ph.D. in 1981, he had postdoctoral appointments at Virginia Tech (1981 to 1984) and Lawrence Livermore National Laboratory (1984 to 1986). In 1986, he started his career in the Department of Physics at Kent State University. He has been a full professor there since 1997. For the past 10 years, his experimental research has been performed in Mainz, Germany as part of the Crystal Ball and A2 Collaborations. He currently has about 120 publications in refereed physics journals and has presented over 30 invited talks at scientific meetings worldwide. He is an experimentalist and phenomenologist.

NOTES ON THE PRESENTATION BY PROF. MANLEY on BARYON SPECTROSCOPY:

This talk describes at an introductory level a method for baryon spectroscopy, and its application to analysis of certain types of scattering. Hadrons are particles that interact through the strong nuclear force: There two kinds: Baryons, or Fermions which have half-integer quantized angular momenta with spins of 1/2 or 3/2 times h/2*(pi). These are ordinarily bound states of 3 quarks. The other type is a bosonic hadron, or meson which has integer quantized angular momenta (1, 2, etc. times h/(2*pi) ) and are bound states of a quark (q) and an anti-quark (qbar). Quarks can have up spin (u) (charge = +2/3 electronic charge) or down spin (d) (-1/3 electronic charge). Spin units are 1/2 times h/(2*pi). There can also be strange quarks with -1/3 electronic charge and slightly more mass than a down quark which are in hyperons, kaons, and antikaons.

The lightest baryons are protons, which have a unit charge of 1, and neutrons, which have zero charge. A proton consists of an up quark, another up quark, and a down quark (noted as uud). It has a mass of 938 MeV (Million electron Volts). Neutrons consist of ddu quarks and have mass of 940 MeV. In particle physics, masses are usually stated in MeV, a unit of energy. But since E=mc^{2}, where c is speed of light, energy E and mass m are related by the constant c^{2} = 1 in these types of calculations. Since these are nearly the same mass, they are generically called alternate states of nucleons (uud or ddu); this designation is similar to electron spins which can be up or down.

In addition to the spin angular momentum, the vector S, there can be orbital momentum of a particle rotating around the center of mass. In the ground state, the lowest energy state, this momentum is zero. Orbital momentum is also quantized; L=0 representing the ground state or s wave of energy, L=1 represents a p wave of energy, L=2 a d wave, L=3 a g wave, L=4 an h wave, then following an alphabetical sequence. The ground state wave function for a nucleon can be written as (1s)3, indicating that there are 3 quarks, each at the s-wave or ground state of energy. Total angular momentum, the vector J is the vector sum of L and S.

If enough energy is applied to a baryon to change the total quark spin from 1/2 to 3/2, a delta baryon is formed. The lightest of these also has a simplified wave function of (1s)3, and is known as delta 1232, since the mass of it is roughly 1232MeV. These have 4 charge states. Nucleons have isospin of I=1/2, and a delta baryon has isospin of I=3/2. Number of charge states for either is 2I+1. Nucleons are excited by scattering a beam of mesons (pions or kaons), photons or electrons off a surface of liquid hydrogen [all protons] or deuterium [a bound pair of proton and neutron]. The resulting nucleon or delta resonance only lasts for about 10-23 seconds after which it decays to a lighter particle. These are involved in intermediate resonances.

Pions are the lightest type of mesons. They may be positively or negatively charged or neutral. Neutral pions are not used experimentally. Various pion reactions were reviewed. They may be elastic or inelastic. Some have secondary reactions. Some can create strange baryons (hyperons), the lightest of which are lambda baryons (I=0) and sigma baryons (I=1). Others create strange mesons, which can be kaons or antikaons. Hyperons can be formed by scattering antikaons off of nucleons.

Prof. Manley's work, over the last 33 years, has been concerned with comparing predicted results using partial-wave analysis with experimental results for the type of reactions described above. This work determined amplitudes of single-energy hadronic reactions and resonance parameters which provided tests of quark model predictions and lattice gauge theory calculations.

We thanked him with applause and he fielded several well-informed questions on specifics.

Bob Erdman, Secretary

Newsletter

Meeting Announcement: MONDAY, November 24, 2014 - TANGIER, 6:00 PM

**Dr. Andrew Tolley**, Department of Physics, Case Western Reserve University

will be speaking on:

**Cosmic Acceleration and Gravity**

**Abstract: **

In recent years there has been a considerable effort to look for modifications to Einstein's theory of gravity at cosmological scales, motivated by the vexing puzzle of dark energy. One such approach looks into the possibility of giving the graviton, the fundamental exchange particle for the gravitational force, a mass. In the last few years we have seen the development of the first consistent theory of `massive gravity' in four dimensions. I will review how these ideas can be important for cosmology, for addressing the cosmological constant problem, and how to go about constructing such consistent theories of gravity and there observational implications.

**The Speaker: **

From 1995 to 1999, Andrew Tolley attended the Jesus College of Oxford University, graduating with a Masters in Physics, receiving First Class Honours, the highest mark in the university. From 1999 to 2003 he attended the Gonville and Caius College at Cambridge University, receiving his Ph.D. in Theoretical Cosmology from the Department of Applied Mathematics and Theoretical Physics. His Thesis Title was "From Big crunch to Big Bang". From 2006 to 2010 he was a Distinguished Research Fellow at the Perimeter Institute in Toronto, where he still does some work. In 2010 he accepted a tenure-track position as an Assistant Professor in Physics Department at Case Western Reserve University. His research interests include early universe cosmology, dark energy, strings and extra dimensions.

Minutes, November 24, 2014

INTRODUCTIONS: Chairman von Meerwall introduced Carol Gould, whose late husband Edwin Gould was a colleague in the Chemistry Department at Kent State University. Anita Kazarian, who became interested in astronomy through Flash Gordon movies, was introduced. Annette Marsolais, a physics student at University of Akron was introduced. David Morley, a "semi-regular" was introduced, as was Lloyd Goettler who retired from University of Akron and his son Robert, a High School Physics Teacher from Santa Barbara.

TREASURER Galehouse reported that the club finances were in reasonable order. He later sent a detailed accounting of the last few months supporting actual balance of $321.45 after this meeting.

PROGRAM CHAIR Lavan reviewed upcoming programs for this club year: In January Dr. Steven Hauck, who spoke to us a few years ago, will return to update us on the Messenger Mission to planet Mercury. In February, Dr. Jeffrey Dyck, Chairman of the Physics Department at John Carroll University will talk on thermoelectrics. Dr. Nicole Steinmetz from Case Western Reserve University will discuss bacteriophages in March. In April, Dr. Nigel Brush from Ashland University will discuss the role of physics in archeology, and our final program on June 1 will be Dr. Jay Reynolds of Cleveland State University updating us on the DAWN spacecraft mission, which has explored one asteroid and is traveling to a second one. A possibility for next year is to have the Provost of the STEM school in Akron tell us about their activities, and Dr. Lavan will present slides of Alaskan auroras, resulting from his visits to an aurora lab in Alaska.

A website where auroras are predicted is: www.gi.alaska.edu/AuroraForecast .

SECRETARY Erdman mentioned there are two high school and middle school science fairs which are interesting and for which technical people, particularly physicists, are needed. Please consider volunteering to judge these events. Both are on January 24, 2015:

Akron Public School science fair, at Akron North High School. Sign up at the following link:

http://www.akronschools.com/departments/ci/teaching-and-learning/science/science-fair/

NEOHSTEM Project fair at KSU Student Union Ballroom. Sign up at www.neohstem.org, click on Project Fair Signup to Mentor & Judge. Contact Sheila King at This email address is being protected from spambots. You need JavaScript enabled to view it. for details.

CHAIR VON MEERWALL INTRODUCED THE SPEAKER: From 1995 to 1999, Andrew Tolley attended the Jesus College of Oxford University, graduating with a Masters in Physics, receiving First Class Honours, the highest mark in the university. From 1999 to 2003 he attended the Gonville and Caius College at Cambridge University, receiving his Ph.D. in Theoretical Cosmology from the Department of Applied Mathematics and Theoretical Physics. His Thesis Title was "From Big crunch to Big Bang". From 2006 to 2010 he was a Distinguished Research Fellow at the Perimeter Institute in Toronto, where he still does some work. In 2010 he accepted a tenure-track position as an Assistant Professor in Physics Department at Case Western Reserve University. His research interests include early universe cosmology, dark energy, strings and extra dimensions.

NOTES ON THE PRESENTATION BY PROF. TOLLEY on

COSMIC ACCELERATION AND GRAVITY:

This is about the origin of cosmic acceleration and gravity. The Pythagorean theorem for 2 dimensions, and the corresponding Cartesian coordinates expression for a distance in 3 dimensions is: s^{2} = x^{2} + y^{2} + z^{2}, where s is the distance between two points x, y, and z apart in the orthogonal 3-dimensional.system.

Einstein's 1905 work treated gravity as a geometrical effect and added a time element, which is subtracted:

s^{2} = - (c^{2})*(t^{2}) + x^{2} + y^{2} + z^{2}, where c is the speed of light, roughly 3*10^{8} meters/second and t is time.

This is called special relativity. Einstein's Professor, Minkowski, pointed out that we need to think of things as being not in space but as being located in a 4-dimensional space-time continuum, per this equation. One implication of this is that if y=z=0, the origin in the space-time continuum corresponds to s=0, or x=ct. Thus travel cannot be greater the speed of light, c. Minkowski visualized this as a "light cone", consisting of two cones on top of each other, joined at their tips, with the junction corresponding to the present time. The lower cone represents past time, the upper represents future time.

In 1915, Einstein described a Metric, a differential equation matrix which describes a curvature of the space-time continuum in the vicinity of a celestial body. This is a fundamental definition of gravity, and is called the general theory of relativity. Lemaitre looked at some early data from Hubbell, and predicted that the universe was continually expanding. He along with Friedmann, Robertson and Walker modified the theory by simply by adding scale factor a(t) which multiplies the Cartesian terms, so the equation now becomes:

s^{2} = - (c^{2})*(t^{2}) + [a(t)^{2}]*(x^{2} + y^{2} + z^{2})

Their work describes the time-varying scale factor a(t) in the above equation; Lemaitre put this together and related it to the Hubble constant (which is not really constant, but time-varying) in 1927. It has recently been shown that a is continually increasing. This has been confirmed by looking at supernovas, the brightest stars in the universe.

Every particle contributes to the cosmological constant, proportional to (mass)^{4}. For example, the electron mass would indicate an energy density contribution to the cosmological constant which is 10^{36} times larger than the observed vacuum energy state. The W boson has more mass, and calculates 10^{56} times the vacuum energy density. This represents a failing of our present understanding of quantum physics. We do not understand the coupling of quantum physics to gravity.

There was discussion of the validity of the General Relativity in all situations. One implication of General Relativity is that the physics is independent of coordinate system [e.g. polar vs. rectangular coordinates]. Also, curvature in space-time appears to be zero (flat, not curved) in a local framework. If the General Relativity Theory is modified, new degrees of freedom are added. These can be described in many ways, and come up often in dark energy theories. Many of these theories are not consistent with more established theories and observations. One of these theories is MASSIVE GRAVITY. One implication of this is that gravitons can have mass. Gravitational waves come from this, in a similar manner to photons and light waves. Part of this is a possible lack of homogeneity in various areas of the universe.

All these theories are expected to yield some consensus on dark energy, the discrepancies described above, and relate them to established theories and observations. Hopefully this will occur soon, and the proliferation of many different theories and the amount of discussion are encouraging.

We thanked Dr. Tolley for his presentation with applause and he discussed several questions on specifics.

Bob Erdman, Secretary