A preliminary analysis of the vertical heat flux at five meters over water

Originally issued as Reference No. 51-70The members of the Marine Meteorology Project of the Woods Hole Oceanographic Institution have designed equipment for the measurement or the vertical heat flux. This consists of a small vertical vane, a heated thermistor anemometer, and a bead thermistor thermometer, all mounted within about 20 centimeters or each other. The instruments were described in detail by Parson and Bunker. The anemometer was not temperature compensated, so that, the wind speed itself is possibly not very accurate; however, the wind speed enters the computation or the heat flux only through the vertical velocity, which is not sensitive to errors in the horizontal speed.Office of Naval Research Under Contract N6onr-27702 (NR-082-021

Testing Lorentz invariance by use of vacuum and matter filled cavity resonators

We consider tests of Lorentz invariance for the photon and fermion sector that use vacuum and matter-filled cavities. Assumptions on the wave-function of the electrons in crystals are eliminated from the underlying theory and accurate sensitivity coefficients (including some exceptionally large ones) are calculated for various materials. We derive the Lorentz-violating shift in the index of refraction n, which leads to additional sensitivity for matter-filled cavities ; and to birefringence in initially isotropic media. Using published experimental data, we obtain improved bounds on Lorentz violation for photons and electrons at levels of 10^-15 and below. We discuss implications for future experiments and propose a new Michelson-Morley type experiment based on birefringence in matter.Comment: 15 pages, 8 table

Between physics and politics - observations and experiences of an involved physicist

Dieser Band dokumentiert die Reden, welche am 7. Juli 2006 in Hamburg anlässlich der feierlichen Eröffnung des Carl Friedrich von Weizsäcker-Zentrum für Naturwissenschaft und Friedensforschung, gehalten wurden. Als Hauptredner waren Alyson J. K. Bailes, die Leiterin des Stockholmer Friedensforschungsinstitutes (SIPRI), Staatsminister a.D., Prof. Egon Bahr, ehemaliger Leiter des Hamburger Friedensforschungsinstituts (IFSH), Prof. Ernst Ulrich von Weizsäcker, ein Sohn des Namensgebers des ZNF, und Prof. Wolfgang Panofsky aus Stanford, USA geladen. Mit der Gründung des Zentrums an der Universität Hamburg, dessen Leitung Prof. Dr. Martin Kalinowski obliegt, hat die naturwissenschaftliche Friedensforschung eine bundesweit einmalige institutionelle Verankerung erhalten. Zusammen mit dem Institut für Friedensforschung und Sicherheitspolitik (IFSH) in Hamburg entsteht ein inter- und multidisziplinär ausgerichteter Forschungsverbund, durch den neue Möglichkeiten eröffnet werden, die Wechselwirkung von Naturwissenschaften, Konflikten und internationaler Sicherheit vor dem Hintergrund der Leitbilder Frieden und Nachhaltigkeit zu erforschen und diese auch in die Ausbildung von Naturwissenschaftlern zu integrieren.This volume documents the speeches given on July 7, 2006 in Hamburg on the occasion of the ceremonial opening of the Carl Friedrich von Weizsäcker Center for Science and Peace Research (Zentrum für Naturwissenschaft und Friedensforschung, ZNF). The keynote speakers were Alyson J. K. Bailes, Head of the Stockholm Peace Research Institute (SIPRI), former Minister of State, Prof. Egon Bahr, former Head of the Hamburg Peace Research Institute (scientific peace research has gained a unique institutional foothold in Germany. Together with the Institut für Friedensforschung und Sicherheitpolitik, IFSH), Prof. Ernst Ulrich von Weizsäcker, a son of the namesake of the ZNF, and Prof. Wolfgang Panofsky from Stanford, USA. With the founding of the Centre at the University of Hamburg, headed by Prof. Dr. Martin Kalinowski, scientific peace research has gained a unique institutional foothold in Germany. Together with the IFSH in Hamburg an inter- and multidisciplinary research network is being established which will open up new opportunities to explore the interaction of natural sciences, conflicts and international security against the background of the guiding principles of peace and sustainability and to integrate them into the training of natural scientists

Rising Level of Public Exposure to Mobile Phones: Accumulation through Additivity and Reflectivity

A dramatic development occurring in our daily life is the increasing use of mobile equipment including mobile phones and wireless access to the Internet. They enable us to access several types of information more easily than in the past. Simultaneously, the density of mobile users is rapidly increasing. When hundreds of mobile phones emit radiation, their total power is found to be comparable to that of a microwave oven or a satellite broadcasting station. Thus, the question arises: what is the public exposure level in an area with many sources of electromagnetic wave emission? We show that this level can reach the reference level for general public exposure (ICNIRP Guideline) in daily life. This is caused by the fundamental properties of electromagnetic field, namely, reflection and additivity. The level of exposure is found to be much higher than that estimated by the conventional framework of analysis that assumes that the level rapidly decreases with the inverse square distance between the source and the affected person. A simple formula for the exposure level is derived by applying energetics to the electromagnetic field. The formula reveals a potential risk of intensive exposure.Comment: 5 pages, 1 fugure; to appear in J. Phys. Soc. Jpn. Vol.71 No.2 in Feb 200

Dank

Am 6. Juli 2006 wurde Professor Wolfgang K. H. Panofsky aus Stanford (USA) die Ehrensenatorwürde der Universität Hamburg in einer Sondersitzung des Akademischen Senats verliehen. Die dabei gehaltenen Ansprachen sind in diesem Band dokumentiert. Der Band wird ergänzt durch ein Interview, das Professor Panofsky am 6. Juli 2006 in Hamburg gegeben hat sowie durch eine tabellarische Übersicht über seinen Werdegang, seine öffentlichen Funktionen und Ehrungen. Wolfgang K. H. Panofsky, geboren 1919 in Berlin, verbrachte den größten Teil seiner Kindheit und seiner Jugendjahre in Hamburg. Von den Nazis zur Emigration gezwungen, kam er 1934 in die USA. Nach dem Studium der Physik in Princeton und am California Institute of Technology erwarb er sich schnell einen großen Ruf in der Forschung zur Elementarteilchenphysik. Er war einer der Initiatoren des Baus eines großen Elektronen-Linearbeschleunigers, der 1972 am Stanford Linear Accelerator Center (SLAC) seinen Betrieb aufnahm. Von 1961 bis zu seiner Emeritierung 1984 war Professor Panofsky dann Direktor dieses Instituts. Durch seine große fachliche Autorität, seine persönliche Integrität und sein an Frieden und Humanismus orientiertes Engagement wurde er zum Vorbild für viele jüngere Wissenschaftler. Sein Vorbild war einer der prägenden Einflüsse, die zur Gründung des Carl Friedrich von Weizsäcker-Zentrums für Naturwissenschaft und Friedensforschung in der Universität Hamburg beigetragen haben.On July 6, 2006, Professor Wolfgang K. H. Panofsky from Stanford (USA) was awarded the honorary senator status of the University of Hamburg in a special session of the Academic Senate. The speeches given are documented in this volume. The volume is supplemented by an interview given by Professor Panofsky on July 6, 2006 in Hamburg, and a tabular overview of his career, his public functions and honours. Wolfgang K. H. Panofsky, born in Berlin in 1919, spent most of his childhood and adolescence in Hamburg. Forced to emigrate by the Nazis, he came to the USA in 1934. After studying physics in Princeton and at the California Institute of Technology, he quickly gained a great reputation in elementary particle physics research. He was one of the initiators of the construction of a large electron linear accelerator, which began operation at the Stanford Linear Accelerator Center (SLAC) in 1972. From 1961 until his retirement in 1984, Professor Panofsky was director of this institute. Through his great professional authority, his personal integrity and his commitment to peace and humanism, he became a role model for many young scientists. His role model was one of the formative influences that contributed to the founding of the Carl Friedrich von Weizsäcker Center for Science and Peace Research at the University of Hamburg

Linear Momentum Density in Quasistatic Electromagnetic Systems

We discuss a couple of simple quasistatic electromagnetic systems in which the density of electromagnetic linear momentum can be easily computed. The examples are also used to illustrate how the total electromagnetic linear momentum, which may also be calculated by using the vector potential, can be understood as a consequence of the violation of the action-reaction principle, because a non-null external force is required to maintain constant the mechanical linear momentum. We show how one can avoid the divergence in the interaction linear electromagnetic momentum of a system composed by an idealization often used in textbooks (an infinite straight current) and a point charge.Comment: 22 pages, 5 figures, to appear in Eur. J. Phy

Charges, Monopoles and Duality Relations

A charge-monopole theory is derived from simple and self-evident postulates. Charges and monopoles take an analogous theoretical structure. It is proved that charges interact with free waves emitted from monopoles but not with the corresponding velocity fields. Analogous relations hold for monopole equations of motion. The system's equations of motion can be derived from a regular Lagrangian function.Comment: 17 pages + 3 figures

Absence of a consistent classical equation of motion for a mass-renormalized point charge

The restrictions of analyticity, relativistic (Born) rigidity, and negligible O(a) terms involved in the evaluation of the self electromagnetic force on an extended charged sphere of radius "a" are explicitly revealed and taken into account in order to obtain a classical equation of motion of the extended charge that is both causal and conserves momentum-energy. Because the power-series expansion used in the evaluation of the self force becomes invalid during transition time intervals immediately following the application and termination of an otherwise analytic externally applied force, transition forces must be included during these transition time intervals to remove the noncausal pre-acceleration and pre-deceleration from the solutions to the equation of motion without the transition forces. For the extended charged sphere, the transition forces can be chosen to maintain conservation of momentum-energy in the causal solutions to the equation of motion within the restrictions of relativistic rigidity and negligible O(a) terms under which the equation of motion is derived. However, it is shown that renormalization of the electrostatic mass to a finite value as the radius of the charge approaches zero introduces a violation of momentum-energy conservation into the causal solutions to the equation of motion of the point charge if the magnitude of the external force becomes too large. That is, the causal classical equation of motion of a point charge with renormalized mass experiences a high acceleration catastrophe.Comment: 13 pages, No figure