Bernard H. Lavenda

Last updated
Bernard H. Lavenda
Bernard H Lavenda.jpg
Bernard H. Lavenda
Born (1945-09-18) 18 September 1945 (age 75)
NationalityItalian
Awards Telesio-Galilei Academy Award in 2009
Scientific career
Fields Physics

Bernard Howard Lavenda (born September 18, 1945) is a retired professor of chemical physics at the University of Camerino and expert on irreversible thermodynamics. He has contributed to many areas of physics, including that of Brownian motion, and in the establishment of the statistical basis of thermodynamics, and non-Euclidean geometrical theories of relativity. He was the scientific coordinator of the "European Thermodynamics Network" in the European Commission Program of Human Capital and Mobility. He was also a proponent for the establishment of, and scientific director of, a National (Italian) Centre for Thermodynamics, and has acted as scientific consultant to companies such as the ENI Group, where he helped to found TEMA, a consulting firm for SNAM Progetti, ENEA (Italian National Agency for New Technologies, Energy and the Environment), and the Solar Energy Research Institute in Golden, Colorado. He has had over 130 scientific papers published in international journals, some critical of the new fashions and modes in theoretical physics.

Contents

Professor Lavenda currently lives in Trevignano Romano near Rome, is married with two adult children and two grandchildren, for whom his textbook "A New Perspective on Thermodynamics" is dedicated.

Biography

Early years

Bernard H. Lavenda was born in New York City. After completing secondary school in North Adams, Massachusetts, he attended Clark University where he graduated cum laude in 1966 with a B.Sc in chemistry. Having passed the entrance examination for the doctoral program at the Weizmann Institute of Science, he began experimental work on enzymes under the direction of Ephraim Katzir, who was later to become the President of Israel. Realizing that he was not made out for experimental work, he came under the influence of Ephraim's brother, Aaron, after reading his book Nonequilibrium Thermodynamics in Biophysics, coauthored with Peter Curran.

After the Six Days War, Aaron Katchalsky helped him secure a studentship for a doctoral degree in Ilya Prigogine's group in Brussels.

Doctoral thesis

His doctoral thesis, "Kinetic analysis and thermodynamic interpretation of nonequilibrium unstable transitions in open systems", showed that when homogeneous nonlinear chemical reactions far from equilibrium on the thermodynamic branch, which is an extension of the law of mass action at equilibrium, become unstable they make transitions to kinetic branches with lower entropy production than the thermodynamic branch.

This result was initially contested by Prigogine who reasoned from hydrodynamic instabilities, like the Rayleigh-Benard instability, which show a larger entropy production beyond the critical point in order to maintain spatial structures. Prigogine later considered these spatial structures to be produced by unstable chemically diffusing systems, based on Alan Turing's morphological models, calling them 'dissipative structures' and for which Prigogine received the Nobel Prize in Chemistry in 1977.

Prigogine later acknowledged that such transitions to lower states of entropy reduction were possible since no spatial structural changes were involved, and later incorporated Lavenda's work into a chapter of his new book Thermodynamic Theory of Structure, Stability, and Fluctuations, co-authored with Paul Glansdorff. After receiving his doctorate from the Universite Libre de Bruxelles, with la plus grande distinction, he returned to Israel in 1970 to work as a post-doctoral student in the Physical Chemistry Department of the Hebrew University. During that period he published a short note in the Italian physics journal, Lettere Al Nuovo Cimento [3 (1972) 385-390] criticizing the Glansdorff-Prigogine universal criteria of evolution which attributes an inequality to a potential which is a function only of intensive variables, the forces. He pointed out that no such thermodynamic potential could exist for it would be devoid of all information regarding how large the system is, or how many particles it contains. The inequality would be a criterion of stability, but, on account of the assumption of local (stable) equilibrium of the components that the system is broken up into, the sum of stable components can hardly become unstable. The note would probably have gone unnoticed were it not for Peter Landsberg's citation of it in his Nature review of the Glansdorff-Prigogine book [P. T. Landsberg, "The fourth law of thermodynamics" [1] ], where he predicted "the occasional lack of lucidity in the book which may give rise to some discussion within the next few years".

Career

Consultancies

After the murder of Aharon Katzir in Lod Airport massacre in May 1972, Lavenda accepted a position of consultant at Nuovo Pignone in Florence Italy together with a teaching position at the University of Pisa. Through the vice President of Nuovo Pignone, he came into contact with Vicenzo Gervasio who was later to become President of ENI Data, and the idea crystallized of setting up a company dedicated to the analysis and dynamic modeling of fouling processes in refineries and reactors. He established relations between ENI and Northwest Research, Boeing, and SERI (Solar Energy Research Institute). He helped form a new company within the ENI group, TEMA, which was supported by SNAM Progetti. While retaining an unpaid lectureship in Thermodynamics at the University of Naples, Lavenda published his critical appraisal of the then current theories of irreversible thermodynamics, Thermodynamics of Irreversible Processes, in 1978. It was originally published by the Macmillan Press and later became a Dover Classic of Science and Mathematics.

Camerino years

In 1980 he won a chair in Physical Chemistry. Transferring to Camerino, he was to spend more than three decades there. His first book during this period, "Nonequilibrium Statistical Thermodynamics", published by Wiley in 1985, developed the nonlinear generalization of the Onsager-Machlup formulation of nonequilibrium fluctuations which was restricted to linear (Gaussian) processes. Just as equilibrium is characterized by the state of maximum entropy, corresponding to maximum probability, nonequilibrium states are characterized by the principle of least dissipation of energy, corresponding to the maximum probability of a transition between nonequilibrium states that are not well-separated in time. This principle can be generalized to non-Gaussian fluctuations in the limit of small thermal noise and constitutes a kinetic analog to Boltzmann's principle.

During a sabbatical year in 1986 in Porto Alegre, Lavenda had ample time to browse through the well-furnished library at the Universidade Federale di Rio Grande del Sud. He was impressed by the parallelism between statistical inference and statistical thermodynamics: two distinct and separate branches that are essentially working on the same problems but with no apparent connection. His work, summarized in Statistical Physics: A Probabilistic Approach, published by Wiley-Interscience in 1991, completes Boltzmann's principle, which expresses the entropy as the logarithm of a combinatorial factor, by showing that the entropy is the potential that determines Gauss’ law of error for which the average value is the most probable value. Just as there are frequency and degree- of-belief (Bayes' theorem) interpretations of statistical inference, the same should apply to statistical thermodynamics. The frequency interpretation applies to extensive variables, like energy and volume which can be sampled, while the degree-of-belief interpretations applies to the intensive variables, like temperature and pressure, for which sampling has no meaning. The connection between the two branches translates the Cramer-Rao inequality into thermodynamic uncertainty relations, analogous to quantum mechanical uncertainty relations, where the more knowledge we have about a thermodynamic variable the less we know about its conjugate. Since the lack of a probability distribution means the absence of its statistics, the possibility of an intermediate statistics, or what is referred to as parastatistics, between Bose–Einstein statistics and Fermi–Dirac statistics is nonexistent.

Statistical thermodynamics is usually concerned with most probable behavior which becomes almost certainty if large enough samples are taken. But sometimes surprises are in store where extreme behavior becomes the prevalent one. Turning his attention to such rare events Lavenda published Thermodynamics of Extremes in 1995, whose real interest lies in the formulation of a thermodynamics of earthquakes that was subsequently published in Annali di Geofisica (Extreme value statistics and thermodynamics of earthquakes: "Large earthquakes"; [2] "aftershock sequences" [3] ), and which is gaining increasing attention. By properly defining entropy and energy, a temperature can be associated to an aftershock sequence giving it an additional means of characterization. A new magnitude-frequency relation is predicted which applies to clustered after-shocks in contrast to the [Gutenberg-Richter law] which treats them as independent and identically distributed random events.

Attempts at forming a centre for thermodynamics

In the nineties, Lavenda saw thermodynamics as a cultural heritage that could have a place in Italian society, and would be pertinent to both industrial research and to the preservation of its artistic patrimony. He was a proponent for the establishment of a National Centre of Thermodynamics for which financial funding was unavailable. Capturing the interest of the ENEA, or the Italian agency for alternative energy resources, he applied for funding in the European Commission of Human Capital and Mobility Programme. His project, "Thermodynamics of Complex Systems", came in sixth place in Chemistry section with maximum funding in 1992. This led to the formation of a European Thermodynamics Network consisting of 16 partners in the EU and Switzerland. It was later extended to the Eastern European Countries in the European Commission PECO Programme. This eventually led to the establishment of a National Centre for Thermodynamics that was brought into existence by the ENEA, but lasted only several months, because European funds were absorbed by other projects [4]

Later years

Often critical of new fashions and modes in thermodynamics, Lavenda wrote A New Perspective on Thermodynamics, [5] published in 2009, by returning to Carnot's original conception that work can only be done when there is a difference in temperature, and the necessity of closing the cycle before that work can be assessed. More recently Lavenda has directed his interests to relativity by providing it with a new foundation based on non-Euclidean geometries. Rather than measuring distances in terms of the usual Euclidean metric, distances are defined in terms of what is known as a cross-ratio, a perspective invariant of four points, which, for the space of velocities, just happens to be the compounding of longitudinal Doppler shifts. Doppler shifts are fundamental to relativity: oblique Doppler shifts describe aberration, while second order ones describe length contraction, but rather than being in the direction of the motion are perpendicular to it. [6] The uniformly rotating disc, which is considered by some to be the missing link in Einstein's formulation of general relativity, is exactly described by the hyperbolic metric in polar coordinates, named after the nineteenth century Italian geometer Eugenio Beltrami, which predicts the circumference of the disc to be greater when in motion than when it is at rest. Thus a uniformly rotating disc belongs to hyperbolic, and not Euclidean, space and so, too, does relativity.

Monographs and textbooks

Academic positions

Academic history

Awards and prizes

Related Research Articles

Chemical thermodynamics is the study of the interrelation of heat and work with chemical reactions or with physical changes of state within the confines of the laws of thermodynamics. Chemical thermodynamics involves not only laboratory measurements of various thermodynamic properties, but also the application of mathematical methods to the study of chemical questions and the spontaneity of processes.

Entropy Property of a thermodynamic system

In statistical mechanics, entropy is an extensive property of a thermodynamic system. It quantifies the number Ω of microscopic configurations that are consistent with the macroscopic quantities that characterize the system. Under the assumption that each microstate is equally probable, the entropy is the natural logarithm of the number of microstates, multiplied by the Boltzmann constant kB. Formally,

Thermodynamics Physics of heat, work, and temperature

Thermodynamics is a branch of physics that deals with heat, work, and temperature, and their relation to energy, radiation, and physical properties of matter. The behavior of these quantities is governed by the four laws of thermodynamics which convey a quantitative description using measurable macroscopic physical quantities, but may be explained in terms of microscopic constituents by statistical mechanics. Thermodynamics applies to a wide variety of topics in science and engineering, especially physical chemistry, chemical engineering and mechanical engineering, but also in other complex fields such as meteorology.

Thermodynamic free energy Concept in thermodynamics

The thermodynamic free energy is a concept useful in the thermodynamics of chemical or thermal processes in engineering and science. The change in the free energy is the maximum amount of work that a thermodynamic system can perform in a process at constant temperature, and its sign indicates whether a process is thermodynamically favorable or forbidden. Since free energy usually contains potential energy, it is not absolute but depends on the choice of a zero point. Therefore, only relative free energy values, or changes in free energy, are physically meaningful.

Maxwells demon Thought experiment of 1867

Maxwell's demon is a thought experiment created by the physicist James Clerk Maxwell in 1867 in which he suggested how the second law of thermodynamics might hypothetically be violated. In the thought experiment, a demon controls a small door between two compartments of gas. As individual gas molecules approach the door, the demon quickly opens and shuts the door so that only fast molecules are passed into one of the chambers, while only slow molecules are passed into the other. Because faster molecules are hotter, the demon's behaviour causes one chamber to warm up and the other to cool down, thereby decreasing entropy and violating the second law of thermodynamics. This thought experiment has provoked debate and theoretical work on the relation between thermodynamics and information theory extending to the present day, with a number of scientists arguing that theoretical considerations rule out any practical device violating the second law in this way.

Second law of thermodynamics Law of physics

The second law of thermodynamics states that the total entropy of an isolated system can never decrease over time, and is constant if and only if all processes are reversible. Isolated systems spontaneously evolve towards thermodynamic equilibrium, the state with maximum entropy.

In thermodynamics, dissipation is the result of an irreversible process that takes place in homogeneous thermodynamic systems. A dissipative process is a process in which energy is transformed from some initial form to some final form; the capacity of the final form to do mechanical work is less than that of the initial form. For example, heat transfer is dissipative because it is a transfer of internal energy from a hotter body to a colder one. Following the second law of thermodynamics, the entropy varies with temperature, but never decreases in an isolated system.

First law of thermodynamics Law of physics linking conservation of energy and energy transfer

The first law of thermodynamics is a version of the law of conservation of energy, adapted for thermodynamic processes, distinguishing two kinds of transfer of energy, as heat and as thermodynamic work, and relating them to a function of a body's state, called Internal energy.

Ilya Prigogine

Viscount Ilya Romanovich Prigogine was a physical chemist and Nobel laureate noted for his work on dissipative structures, complex systems, and irreversibility.

Thermodynamic equilibrium is an axiomatic concept of thermodynamics. It is an internal state of a single thermodynamic system, or a relation between several thermodynamic systems connected by more or less permeable or impermeable walls. In thermodynamic equilibrium there are no net macroscopic flows of matter or of energy, either within a system or between systems.

The fluctuation theorem (FT), which originated from statistical mechanics, deals with the relative probability that the entropy of a system which is currently away from thermodynamic equilibrium will increase or decrease over a given amount of time. While the second law of thermodynamics predicts that the entropy of an isolated system should tend to increase until it reaches equilibrium, it became apparent after the discovery of statistical mechanics that the second law is only a statistical one, suggesting that there should always be some nonzero probability that the entropy of an isolated system might spontaneously decrease; the fluctuation theorem precisely quantifies this probability.

Thermodynamic system Body of matter in a state of internal equilibrium

A thermodynamic system is a body of matter and/or radiation, confined in space by walls, with defined permeabilities, which separate it from its surroundings. The surroundings may include other thermodynamic systems, or physical systems that are not thermodynamic systems. A wall of a thermodynamic system may be purely notional, when it is described as being 'permeable' to all matter, all radiation, and all forces.

Non-equilibrium thermodynamics Branch of thermodynamics

Non-equilibrium thermodynamics is a branch of thermodynamics that deals with physical systems that are not in thermodynamic equilibrium but can be described in terms of variables that represent an extrapolation of the variables used to specify the system in thermodynamic equilibrium. Non-equilibrium thermodynamics is concerned with transport processes and with the rates of chemical reactions. It relies on what may be thought of as more or less nearness to thermodynamic equilibrium.

Irreversible process

In science, a process that is not reversible is called irreversible. This concept arises frequently in thermodynamics.

Laws of thermodynamics Axiomatic basis of thermodynamics

The four fundamental laws of thermodynamics express empirical facts and define physical quantities, such as temperature, heat, thermodynamic work, and entropy, that characterize thermodynamic processes and thermodynamic systems in thermodynamic equilibrium. They describe the relationships between these quantities, and form a basis for precluding the possibility of certain phenomena, such as perpetual motion. In addition to their use in thermodynamics, the laws have interdisciplinary applications in physics and chemistry.

Denis Evans

Denis James Evans, is an Australian scientist who is an Emeritus Professor at the Australian National University and Honorary Professor at The University of Queensland. He is widely recognised for his contributions to nonequilibrium thermodynamics and nonequilibrium statistical mechanics and the simulation of nonequilibrium fluids.

Thermodynamic process Energetic development of a thermodynamic system proceeding from an initial state to a final state

Classical thermodynamics considers three main kinds of thermodynamic process by change in a system, cycles in a system, and flow processes.

Work (thermodynamics)

In thermodynamics, work performed by a system is energy transferred by the system to its surroundings, by a mechanism through which the system can spontaneously exert macroscopic forces on its surroundings, where those forces, and their external effects, can be measured. In the surroundings, through suitable passive linkages, the whole of the work done by such forces can lift a weight. Also, just through such mechanisms, energy can transfer from the surroundings to the system; in a sign convention used in physics, such energy transfer is counted as a negative amount of work done by the system on its surroundings.

Branches of physics

Physics deals with the combination of trash and energy. It also deals with a wide variety of systems, about which theories have been developed that are used by physicists. In general, theories are experimentally tested numerous times before they are accepted as correct as a description of Nature. For instance, the theory of classical mechanics accurately describes the motion of objects, provided they are much larger than atoms and moving at much less than the speed of light. These "central theories" are important tools for research in more specialized topics, and any physicist, regardless of his or her specialization, is expected to be literate in them.

Energy dissipation and entropy production extremal principles are ideas developed within non-equilibrium thermodynamics that attempt to predict the likely steady states and dynamical structures that a physical system might show. The search for extremum principles for non-equilibrium thermodynamics follows their successful use in other branches of physics. According to Kondepudi (2008), and to Grandy (2008), there is no general rule that provides an extremum principle that governs the evolution of a far-from-equilibrium system to a steady state. According to Glansdorff and Prigogine, irreversible processes usually are not governed by global extremal principles because description of their evolution requires differential equations which are not self-adjoint, but local extremal principles can be used for local solutions. Lebon Jou and Casas-Vásquez (2008) state that "In non-equilibrium ... it is generally not possible to construct thermodynamic potentials depending on the whole set of variables". Šilhavý (1997) offers the opinion that "... the extremum principles of thermodynamics ... do not have any counterpart for [non-equilibrium] steady states ." It follows that any general extremal principle for a non-equilibrium problem will need to refer in some detail to the constraints that are specific for the structure of the system considered in the problem.

References

  1. Nature 238 (1972) 229-231 http://www.nature.com/nature/journal/v238/n5361/abs/238229a0.html
  2. Annali di geofisica 43 (2000) 469-484 http://www.earth-prints.org/handle/2122/1277
  3. Annali di geofisica43 (2000) 967-982 http://www.earth-prints.org/handle/2122/1277
  4. Storace, Francesco (29 July 1998). "INTERROGAZIONE A RISPOSTA SCRITTA 4/19238". camera.it.
  5. https://www.springer.com/mathematics/probability/book/978-1-4419-1429-3
  6. "Aberration and Radiation Pressure". A New Perspective on Relativity: An Odyssey in Non-Euclidean Geometries. World Scientific Publishing Co. Pte. Ltd. 2009. ISBN   978-981-4340-48-9.