Section Tw o AERONAUTICS Areas of Study and The...

AERONAUTICS

The Guggenheim Aeronautical Laboratory, the KarmanLaboratory of Fluid Mechanics and Jet Propulsion, and theFirestone Flight Sciences Laboratory form the GraduateAeronautical Laboratories, widely known as GALCIT. In thiscomplex are housed the applied and computational mathematicsgroup and the hydrodynamics and solid and structural mechanicslaboratories, as well as the various disciplines making up the broadfield known as aeronautics.

Areas of ResearchAeronautics has evolved at Caltech from a field of basic researchand engineering, primarily related to the development of the air-plane, into a wide discipline encompassing a broad spectrum ofbasic as well as applied problems in fluid dynamics and mechanicsof solids and materials. Research at GALCIT has traditionally pio-neered exploration of new areas that have anticipated subsequenttechnological demands. This tradition places a high premium onan in-depth understanding of fields both closely and remotelyrelated to the behavior of fluids, solids, and structures, such asphysics, applied and computational mathematics, geophysics, mate-rials science, electronics, and even astrophysics. As a consequence,GALCIT students are known and sought after for their broad yetintense education and for their ability to deal with new and chal-lenging problems.

Major areas of study and research currently pursued by aero-nautics students at Caltech are briefly described below.■ Physics of Fluids. Fluid dynamics as a discipline is as much a part

of physics as of engineering. Physics of fluids refers to researchin areas closer to applied physics than to direct technical appli-cations. Present active research includes studies in gasdynamicsand hypervelocity flows, diffraction of shock waves, detonationwaves, shock-induced Rayleigh-Taylor instability, and transientsupersonic jets, the development of laser scattering diagnostictechniques for fluid-flow measurements, study of structures andmechanics in transition and turbulence, and studies of two-phase flows and turbulent mixing.

■ Computational Fluid Dynamics. Many of the subjects studiedexperimentally at GALCIT are also being investigated bynumerical simulation. Present active research areas in computa-tional techniques include direct numerical simulation, particlemethods for flow simulation, subgrid-scale models for com-pressible and incompressible flows, large-eddy simulation meth-ods, flows with shocks, high-explosive interactions withdeformable boundaries, and detailed chemical reaction kineticsin flames and detonations.

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S e c t i o n Tw o

Areas of Study andResearch

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Areas of Study and Research

work in the propulsion area has centered on the fluid dynamicproblems associated with combustion, solid propellant rocketmotor instabilities, fluid dynamics of scramjets, and pulse deto-nation engines.

■ Aerospace Technology. The industrial utilization and explorationof space must address a wide range of engineering problems.Examples of research activities include light-weight structuresfor large aperture systems, material and structural behavior inextreme temperature and radiation environments, spacecraftshielding against hypervelocity impact threats, the mechanicsof sample containment for planetary protection, low-g biome-chanics, biomimetics of locomotion in planetary atmospheres,hypersonic re-entry into planetary atmospheres, spacecraftpropulsion, guidance, navigation and control, and launch vehi-cle performance and safety. Opportunities exist for research incollaboration with the Jet Propulsion Laboratory.

Physical FacilitiesThe Graduate Aeronautical Laboratories contain a diversity ofexperimental facilities in support of the programs described above.Low-speed wind tunnels include the John W. Lucas Adaptive WallTunnel, the Merrill Wind Tunnel, which can be operated by a sin-gle person, and special-purpose flow facilities. Both a high-speedwater tunnel (100 feet per second) and a free-surface water tunnelare housed in the hydrodynamics laboratory; they are used forstudies of acoustics, laminar-turbulent flow transition, and thestructure of turbulent shear flows. Smaller water channels and atow tank for studies of wave motion and flow visualization are alsoavailable. For investigations of high-speed flows there is a Ludwiegtube, a supersonic shear layer facility, and the T5 shock tunnel forstudying hypervelocity gas flows up to 7 km/s. Shock tubes andother special facilities are available for the study of extreme tem-peratures, shock waves, deflagrations, detonations, acoustics, andcombustion at variable pressure conditions.

The solid mechanics laboratories contain standard as well asspecial testing facilities for research related to aircraft, spacecraftstructures, and failure/fracture behavior of materials under staticand dynamic loads, including three servohydraulic facilities, two ofwhich operate on a “tension/torsion’’ mode. A range of digital andfilm high-speed cameras offering recording at rates from still to 2million frames per second are available for the study of fast phe-nomena, such as wave propagation, dynamic buckling, and themechanics of static and dynamic fracture. Dynamic testing facilitiesinclude specialized electromagnetic loading devices (stored energy~120 KJ), a drop weight tower, split Hopkinson bars (axial/torsion-al), and plate impact apparatus. Diagnostic devices include full-field interferometric and temperature measurements, both for stat-ic and dynamic applications. State-of-the-art facilities are available

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Aeronautics

■ Technical Fluid Mechanics.These areas are related to a variety ofmodern technological problems and, in addition, to the tradi-tional aeronautical problems of drag, wing stall, and shear flowmixing. Additional areas of activity include bluff-body aerody-namics, fluid-structure interaction, turbulent combustion, lami-nar diffusion flames and their instabilities, explosions, hydrody-namics and two-phase flows, interaction of vorticity with free-surface, cardiac flows, swimming and flying, and active and pas-sive control of transition and turbulence. Acoustics problemsstudied include jet noise, combustion noise, and instabilitiessuch as the generation of organ pipe oscillations in large burn-ers of electric generating plants.

■ Mechanics of Materials. Mechanics of materials research involvesboth the quasi-static and dynamic characterization of solids. Inorder to understand materials for applications in a wide rangeof structures germane to aeronautics as well as other engineer-ing disciplines, both the physical foundations of that behavior aswell as the mathematical or numerical representation of suchbehavior needs to be understood. Accordingly, studies involvematerial response at both the macroscopic (continuum) scalesand the micro- and nanoscales. Of interest are the typical engi-neering metals, multiphase (composite) materials, polymers andceramics, as well as active materials used in structural actuationand controls.

■ Computational Solid Mechanics. Computational solid mechanicsaddresses phenomena ranging from the atomistic scale, e.g.,nanoindentation, to the structural scale, e.g., fracture of aircraftcomponents. It provides an indispensable tool for understand-ing the relation between structure and mechanical properties ofmaterials, for predicting the efficiency of such industrialprocesses as machining and metal forming, and for assessing thesafety of such structures as airplanes, automobiles, and bridges.The goals and objectives of this activity are to provide a state-of-the-art environment for the development of numerical meth-ods in solid mechanics, to provide the computational resourcesrequired for medium-scale simulations in solid mechanics, andto serve as an instructional facility for advanced courses.

■ Mechanics of Fracture. An active effort is being made to under-stand mechanisms in a wide range of fracture problems. Aspectsthat are studied include quasi-static and dynamic crack growthphenomena in brittle and plastically deforming solids, polymersand advanced composites, as well as fatigue and failure of adhe-sive bonds. Research areas adjunct to fracture studies in poly-mers are the nonlinearly viscoelastic behavior of polymericsolids and issues of durability in advanced aerospace structures.

■ Aeronautical Engineering and Propulsion. Research in the aero-nautical engineering area includes studies of airplane trailingvortices and separated flows at high angles of attack. Research

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The group primarily interested in applied and computationalmathematics currently consists of approximately 25 students andfive professors. Also, each year many distinguished visitors comeeither to present lectures or remain in residence for large parts ofthe academic year.

Areas of ResearchResearch is particularly strong in theoretical and computationalfluid mechanics, theoretical and computational materials science,numerical analysis, ordinary and partial differential equations,integral equations, linear and nonlinear wave propagation, waterwaves, bifurcation theory, perturbation and asymptotic methods,stability theory, variational methods, approximation theory, statisti-cal estimation, computational harmonic analysis, stochasticprocesses, signal and imaging processing, inverse problems, mathe-matical biology, large-scale scientific computing, and relatedbranches of analysis.

APPLIED MECHANICS

Areas of ResearchAdvanced instruction and research leading to degrees of Master ofScience and Doctor of Philosophy in applied mechanics are offeredin such fields as elasticity; plasticity; wave propagation in solidmedia; mechanics of quasi-static and dynamic fracture; dynamicsand vibrations; finite element analysis; and stability, control, andsystem identification of mechanical and structural systems.

Research studies in these areas that illustrate current interestsinclude linear and nonlinear random vibrations of uncertaindynamical systems; structural dynamics and control for earthquakeand wind loads; linear and nonlinear problems in static and dynam-ic elasticity, plasticity, and viscoelasticity; computational mechanics;mechanics of time-dependent fracture; chaotic behavior of dynami-cal systems; and material instabilities and phase transformations insolids.

Physical FacilitiesIn addition to the regular facilities in the Division of Engineeringand Applied Science, which include extensive computing facilities,certain special facilities have been developed in connection withapplied mechanics activities. The vibration laboratory is equippedwith a good selection of modern laboratory apparatus and instru-mentation for experimental research in shock and vibration, andthe earthquake engineering research laboratory contains special-ized equipment for vibration tests of buildings, dams, and otherstructures, and for the recording and analysis of strong-motionearthquakes. The solid mechanics laboratory located in the

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for scanning microscopy (AFM, STM) and electromechanical char-acterization of materials.

State-of-the-art electronic instrumentation is being developedand used. Extensive use is made of computer systems for real-timecontrol of experiments, for data acquisition, processing, and stor-age, and for digital image processing. Computational facilitiesinclude powerful workstations, on-campus parallel processingmachines, and remote supercomputers such as those generallyavailable at NSF, NASA, and DOE centers. Graphics workstationsare available to support research in computational fluid dynamicsand solid mechanics.

APPLIED AND COMPUTATIONAL MATHEMATICS

An interdisciplinary program of study in applied and computation-al mathematics that leads to the Ph.D. degree is offered by theInstitute. In addition to various basic and advanced courses taughtby the applied and computational mathematics faculty, broad selec-tions are available in mathematics, physics, engineering, and otherareas. Students are expected to become proficient in some specialphysical or nonmathematical field. A subject minor in applied com-putation is offered jointly with the computer science option.

In addition to the applied and computational mathematics fac-ulty, professors from other disciplines such as mathematics,physics, engineering, biology, etc., supervise research and offercourses of special interest. Close contact is maintained with experi-mental programs in fluid and solid mechanics and with researchgroups in parallel computation. The applied and computationalmathematics group has access to supercomputers and concurrentcomputers, and has a variety of its own computers, graphics termi-nals, and other equipment. Library facilities are excellent, compris-ing all the journals, a complete general library, and a specialresearch library in engineering and applied science.

The present graduate program is one leading mainly to thePh.D. degree. The curriculum consists of two types of courses:those that survey the methods used in applied and computationalmathematics, and those that have a special applied and computa-tional mathematics flavor and represent active research interests ofthe members of the faculty. Among the latter have been wavemotion, perturbation theory, fluid mechanics, stochastic processes,wavelet analysis, signal processing, numerical analysis, and compu-tational fluid dynamics. Through study outside of applied andcomputational mathematics, each student is expected to becomecompetent in some special physical or nonmathematical field. Inthis way, subjects for research appear naturally, and a broad educa-tional program is provided.

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Areas of Research and Physical FacilitiesResearch in applied physics covers a broad spectrum of activities,ranging from nanostructured materials, solid state devices, andphotonics to biophysics and plasma physics. There is research inprogress in single-molecule biophysics, microfluidics, nanostruc-ture fabrication and application in photonics and electronics, ultra-high-speed fiber optic devices and communications systems, com-pound semiconductor materials and device physics, spin-dependenttransport, photovoltaics, chemical vapor deposition processes, andfluid dynamics. The research program is centered in the Thomas J.Watson, Sr., Laboratories of Applied Physics. This 40,000-square-foot building contains research laboratories including a centralmicro/nano fabrication facility as well as offices, conference rooms,and a classroom, nestled around an attractive courtyard.

ASTROPHYSICS

The astronomical observatories at Palomar and Mauna Kea,and the Owens Valley Radio Observatory and the CaltechSubmillimeter Observatory, together constitute a unique andunprecedented concentration of ground-based facilities inastronomy.

Access to satellite-based infrared observations is provided byCaltech’s Infrared Processing and Analysis Center (IPAC) and theSpitzer Science Center (SSC). For example, IPAC currently sup-ports a number of NASA missions: 2MASS, an all-sky survey at 2microns, and the Infrared Space Observatory (a mission of theEuropean Space Agency). The SSC will conduct the science opera-tions of the Spitzer Space Telescope—one of the great space obser-vatories. The GALEX mission, an upcoming space UV survey ofthe sky, is also used by Caltech.

The Division of Physics, Mathematics and Astronomy also con-ducts work in theoretical astrophysics, laboratory astrophysics,gravitational-wave physics, and infrared and submillimeter astrono-my, as well as studies of the cosmic microwave background(CMBR).The radio astronomy group works in close collaborationwith the optical astronomers in Pasadena. There is close coopera-tion between these groups and the students and astronomersinterested in planetary physics and space science. Caltech is alsoamong the leaders in the development of the National VirtualObservatory.

As a result of the cooperation possible over a broad range ofastronomy and theoretical astrophysics, unsurpassed opportunitiesexist at Caltech for advanced study and research. Courses of studydepend upon a broad and thorough preparation in physics, mathe-matics, and other relevant subjects; the faculty offers advanced

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Astrophysics

Graduate Aeronautical Laboratories contains extensive testingequipment for the study of fracture and structural failure. Excellentcomputing facilities are available through the campus computingnetwork and in the specialized centers of various research groups.

APPLIED PHYSICS

An interdivisional program in applied physics for both undergradu-ate and graduate study was initiated in 1970. Applied physics atCaltech is in a fortunate position: The comparatively small size ofCaltech coupled with its great strength in both the pure sciencesand engineering make it possible to have a faculty with a wideinterest in the application of modern physics to technology, with-out losing close interaction with “pure subjects.” At present, mem-bers of four divisions—Engineering and Applied Science; Physics,Mathematics and Astronomy; Chemistry and ChemicalEngineering; and Geological and Planetary Sciences—participatein instruction and research in applied physics leading to a B.S.degree as well as to M.S. and Ph.D. degrees.

The program is designed for students who are deeply interestedin physics but at the same time are fascinated by the interrelationof physical problems and technological development; i.e., studentswho like to work with problems in physics that originate from orresult in applications. A sharp division between “pure” and“applied” physics or between applied physics and engineering can-not be drawn, and the option of applied physics should be consid-ered a bridge rather than a divider. A student is expected to have athorough background in physics, as well as a broad background inrelated fields of technology.

Members of the faculty involved with the educational andresearch activities in applied physics remain members of theirrespective divisions. Graduate students who choose the appliedphysics option will do research in one of the cooperating divisions.

In setting up the undergraduate curriculum, every effort hasbeen made to facilitate the transition into and out of the option. Ingeneral an undergraduate student in applied physics will devotesomewhat more time to the study of condensed matter than willthe “pure’’ physicist. Since it is expected that most students will beinterested in experimental research, a special effort has been madeto set up challenging laboratory courses and to provide an oppor-tunity to do a senior thesis.

For first-year graduate students and adventurous seniors, a setof basic courses covering broad areas in applied physics is available,supplemented by a set of more specialized courses often closelyrelated to a specific research effort.

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area make possible investigations of the fine structure of the solaratmosphere. Emphasis is on high-resolution spectroscopy, magne-tography, and cinematography. A major effort is the study of solaroscillations.

The Owens Valley Radio Observatory is in a radio-quiet loca-tion 400 km north of Pasadena, near Big Pine, California. Its facili-ties include a 40-meter telescope, a six-element millimeter-wavesynthesis interferometer array, a five-element interferometer forsolar studies, and a 5.5-meter telescope dedicated to observationsof the microwave background radiation. The high-precision 10-meter telescopes of the millimeter array are used at wavelengths of1.3 to 4 mm to map the distribution of interstellar gas and dust instar-forming regions of our own and other galaxies. The array alsoenables detailed studies of the sun, planetary atmospheres, and theenvelopes around evolved stars. These telescopes, which areequipped with very sensitive cryogenically cooled receivers andsophisticated signal-processing and data-recording systems, giveCaltech staff and students the widest range of observing opportuni-ties available at any university-related radio observatory in theworld.

The Caltech 10-meter Submillimeter Observatory, located onMauna Kea, Hawaii, was completed in 1986 for the study of thechemistry and physics of planets and cool regions of the interstellarmedium.

A special purpose instrument for imaging the microwave back-ground, located in Chile, is now operational.

The Keck Foundation funded the construction of two 10-meteroptical-infrared telescopes, operated jointly with the University ofCalifornia as part of an interferometer. Each Keck Telescope hasfour times the power of the Palomar 200-inch. They can be com-bined as an interferometer of unprecedented power. These are thetwo largest optical-infrared telescopes in the world, equipped withadaptive optics and state-of-the-art optical and infrared instrumen-tation, and they have made numerous fundamental advances inastronomy and cosmology.

BIOCHEMISTRY AND MOLECULAR BIOPHYSICS

Biochemistry and molecular biophysics has been established as aninterdisciplinary program, at the interface of biology, chemistry,and physics, that seeks to understand the chemistry of life. Thus,biochemists and molecular biophysicists study the atomic structureand folding of biopolymers; their interactions with each other andwith small molecules; and the roles of particular biopolymers andbiopolymer assemblies in cellular physiology. The basic buildingblock of life is the cell; the intellectual focus of modern biochem-

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Biochemistry and Molecular Biophysics

instruction in astronomy, astrophysics, solar physics, planetaryphysics, and astronomical instrumentation and techniques.

Areas of ResearchBoth observational and theoretical astrophysics are actively pur-sued. Topics of current interest in optical and infrared astronomyinclude observational cosmology; spectroscopic and spectrophoto-metric studies of quasars and galaxies; studies of the dynamics andcomposition of galaxies and clusters, nebulae, and interstellar mat-ter; planet and star formation; statistical studies pertinent to thestructure of the galaxy; globular clusters; gamma-ray bursts; neu-tron stars; digital sky surveys; the physics of solar phenomena; andmany others.

Research in planetary and solar system astronomy is pursuedin cooperation with groups in the Division of Geological andPlanetary Sciences.

The research in radio astronomy covers cosmology, via observa-tions of the microwave background radiation, and the physicalproperties of galactic and extragalactic radio sources, includingquasars, pulsars, radio galaxies, stellar envelopes, and the planets.The properties of the interstellar medium in our own and othernearby galaxies are investigated in spectroscopic studies of variousatomic and molecular spectral lines.

Theoretical astrophysics is pursued not only in the astrophysicsdepartment, but in physics and geology as well, and at Caltechincludes work on supernovae, pulsars, stellar structure and evolu-tion, stellar and planetary atmospheres, interstellar and intergalac-tic matter, the physics of radio sources, nucleosynthesis, relativity,and cosmology.

Physical FacilitiesThe Rockefeller Boards provided, in 1928, for the construction bythe Institute of an astronomical observatory on Palomar Mountain,equipped with a 200-inch reflecting telescope, 48-inch SamuelOschin and 18-inch Schmidt wide-angle telescopes, and other aux-iliary instruments, together with an astrophysical laboratory on theInstitute campus. The 48-inch Samuel Oschin Telescope has madepossible complete surveys of the northern sky. It is now beingequipped with a major new digital camera, which will lead to a newgeneration of sky surveys. The Palomar telescopes have moderninstrumentation and detectors designed for both optical andinfrared wavelengths. The 200-inch Hale Telescope has been usedto make many historical, fundamental discoveries ever since itscommissioning in 1948, and through the present day. It is now alsoused for pioneering advances in adaptive optics.

A multipurpose solar equatorial telescope at an observing sta-tion at Big Bear Lake is now run jointly with the New JerseyInstitute of Technology. The unique atmospheric conditions in this

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BIOENGINEERING

The bioengineering option at Caltech is concerned with theenhanced analysis and understanding of complex biological sys-tems. Researchers in this option also seek to apply engineeringprinciples to the synthesis of novel biological and biomimetic sys-tems. While the bioengineering option operates within theDivision of Engineering and Applied Science, it is a full collabora-tion between the Divisions of Engineering and Applied Science,Biology, and Chemistry and Chemical Engineering.

At a variety of levels of organization, from the molecular to thecellular to the organismal levels, biology is becoming more accessi-ble to approaches that are commonly used in engineering—mathe-matical modeling, system theory, computation, and abstractapproaches to synthesis. Conversely, the accelerating pace of dis-covery in biological science is suggesting new design principles thatmay have important practical applications in man-made systemdesign. Synergism created at the interface of biology, engineering,and chemistry offers unprecedented opportunities to meet chal-lenges in these areas. The educational goal of this option is to traingraduate students in both engineering and biological science,thereby allowing them to integrate theses approaches. Such stu-dents should have or acquire a strong background in mathematicsand physical sciences, biology and chemistry. As biologists, bio-engineers will study existing biological systems to deduce and applydesign and system principles, whereas as engineers, they can createnew biological structures and new types of man-made systems.

Areas of ResearchTwo major research themes of this option are “synthesis”and“analysis.” The notion of synthesis includes the synthesis of novelbiomaterials and biosystems, as well as biologically inspired man-made systems. The analysis theme seeks to exploit the concept of“reverse engineering” of biological systems; that is, to understandthe physical and engineering principles used by nature in biologicalsystems. To achieve this goal, a significant component of the pro-gram involves system theory, informatics, mathematical modeling,optics, microfabrication, and biochemical analysis techniques as isnecessary to “reverse engineer” and understand complex biologicalsystems. Research in this option focuses on the development ofnew instrumentation for research and clinical applications.

The main active areas of research in bioengineering by theassociated faculty include

■ Biomaterial engineering;■ Tissue engineering;■ Cardiovascular fluid dynamics;■ Microfluidic devices;

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Bioengineering

istry and molecular biophysics is to understand how individualparts interact to give cells their wide spectrum of functions. In par-ticular, biochemistry and molecular biophysics addresses the prin-ciples through which the individual components of cells combinein an orderly self-association to produce their form, their function,and their dynamic behavior.

Areas of ResearchGeneral areas of research represented within the option includesignal transduction, cell cycle, DNA and RNA structure andmetabolism, control of gene transcription during development,electron transport proteins and bioenergetics, biological catalysis,macromolecular structure, membrane proteins, and biotechnologyand biomolecular engineering. More specific examples of biologi-cal phenomena currently under study include the transduction ofsignals received by cell surface receptors into an appropriateresponse, as in chemotaxis or transmission of signals across synap-ses in the nervous system; the replication of DNA; the biochemicalnetworks that control initiation and termination of cell division;the controlled transcription of DNA sequences in the genome intoRNA and the processing of this RNA into mRNA and the subse-quent translation into protein; the molecular mechanisms control-ling the differentiation of precursor cells into specialized cells suchas neurons, lymphocytes, and muscle cells; the mechanisms bywhich synaptic transmission in the brain is regulated during think-ing and the formation of memories; the processes, driven by funda-mental principles of chemical bonding and molecular energetics,by which a given linear sequence of amino acids folds into a specif-ic three-dimensional structure in the appropriate cellular environ-ment; how electrons move within a cell to accomplish the manyredox reactions necessary for life; how light is harvested by pho-topigments and is perceived in vision; the function of integralmembrane proteins in energy and signal transduction processes;and the mechanisms by which enzymes both efficiently and specifi-cally catalyze biochemical interconversions. This fundamentalunderstanding of the molecular basis of biological processes pro-vides a powerful base for the development of applications in medi-cine, including biotechnology and rational drug design, and in thechemical industry, where nucleic acids, proteins, and their analogsare now being used in the development of chemical systems fornovel applications, and where mutagenesis and selection systemsare used to produce novel materials.

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within the Division of Biology. A comprehensive program ofresearch and instruction in neurobiology has been formulated tospan from molecular and cellular neurobiology to the study of ani-mal and human behavior including the computational modeling ofneural processes.

A new geobiology option is described in the Geological andPlanetary Sciences section.

Physical FacilitiesThe campus biological laboratories are housed in six buildings: theWilliam G. Kerckhoff Laboratories of the Biological Sciences, theGordon A. Alles Laboratory for Molecular Biology, the NormanW. Church Laboratory for Chemical Biology, the Mabel andArnold Beckman Laboratories of Behavioral Biology, the BraunLaboratories in Memory of Carl F and Winifred H Braun, theBeckman Institute, and the Broad Center for the BiologicalSciences. They contain classrooms and undergraduate laboratories,as well as research laboratories where both undergraduate andgraduate students work in collaboration with faculty members.Special facilities include rooms for the culturing of mutant types ofDrosophila, a monoclonal antibody production facility, a fluores-cence-activated cell sorter, scanning and transmission electronmicroscopes, a confocal microscope facility, a magnetic resonanceimaging center, a transgenic mouse facility, a state-of-the-artmicrochemical facility for sequencing and synthesizing biologicallyimportant macromolecules, and a protein expression and purifica-tion center.

About 50 miles from Pasadena, in Corona del Mar, is theWilliam G. Kerckhoff Marine Laboratory. This laboratory pro-vides facilities for research in cellular and molecular biology usingmarine animals, and for collecting and maintaining these animals.

BIOTECHNOLOGY

Biotechnology is a growing area of interdisciplinary research with along tradition at Caltech. It includes a wide range of researchopportunities in the Divisions of Biology, Chemistry and ChemicalEngineering, and Engineering and Applied Science. Areas ofemphasis include the development and application of new methodsand instruments for studying a spectrum of biological problemsranging from the structure, function, and chemistry of key macro-molecules such as proteins and DNA to the imaging of cellularprocesses or the complex problems of neural systems. Other pro-grams focus on the creation, study, and use of novel microorgan-isms and proteins, combining classical and molecular geneticapproaches with modern chemistry and engineering science. Newchallenges in data analysis and molecular modeling bring together

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■ Microsensors for clinical and research applications;■ Biological and biomedical imaging;■ Metabolic and protein design and engineering;■ Principles of evolutionary design;■ Neural prostheses;■ Optical trapping and manipulation of molecules

and particles;■ Biomechanics of the musculoskeletal system;■ Biomimetics (mechanophysiology of swimming,

walking, undulating, and flying);■ Transport phenomena in biological systems;■ Robotic technology for minimally invasive surgery;■ Systems biology;■ Modeling of regulatory networks.

BIOLOGY

Recent dramatic progress in our understanding of the nature of lifehas revolutionized the science of biology. Applications of the meth-ods, concepts, and approaches of modern mathematics, physics,chemistry, and information science are providing deep insight intobasic biological problems such as the manner in which genes andviruses replicate themselves; the control of gene expression in cells;the regulation of cellular activity; the mechanisms of growth anddevelopment; and the nature and interactions of nerve activity,brain function, and behavior. Qualified experimental and computa-tional biologists will find opportunities for challenging work inbasic research as well as in medicine and in biotechnology.

Because of the eminent position of the California Institute ofTechnology in both the physical and biological sciences, students atthe Institute have an unusual opportunity to be introduced to mod-ern biology.

Areas of ResearchResearch (and graduate work leading to the Ph.D. degree) ischiefly in the following fields: biochemistry, biophysics, cell biolo-gy, developmental biology, genetics, immunology, molecular biolo-gy, structural biology, neurobiology, and virology. Biochemicalmethodology plays an important role in many of these fields, andthere is extensive interaction with related programs in biochem-istry within the Division of Chemistry and Chemical Engineering,notably the new biochemistry and molecular biophysics option.

The programs in cellular, molecular, and developmental biologyare based upon approaches derived from biochemistry, biophysics,and genetics that offer new possibilities for expanded insight intolong-standing problems. Neurobiology is a major area of emphasis

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■ Cellular Engineering. Quantitative analysis and redesign ofmolecular events governing cell behavior.

■ Catalysis and Biocatalysis. Synthesis of molecular sieves andorganic-inorganic hybrid materials. Synthesis of inorganicmembranes for gas separations and catalysis. Biologicalroutes to the synthesis of chemicals.

■ Ceramics and Electronic Materials. Aerosol formation ofceramic and semiconductor nanoparticles and nanoparticle-based devices. Synthesis of inorganic materials and ceramics.Synthesis and characterization of quantum dots and nanostruc-tural materials.

■ Plasma Processing of Semiconductors. Pattern etching and deposi-tion. Modeling and simulation of pattern-dependent effects.Chemical reaction dynamics of plasma-surface interactions.

■ Microplasmas. Sources of reactive radicals and ions at high pres-sures. Microreactors for gas conversion/pollutant destruction.Synthesis of nanocrystals. VUV-excimer radiation emitters.

■ Environmental Chemical Engineering. Physics and chemistry ofatmospheric gases and aerosols.

■ Aerosols and Colloids. Nucleation and growth of particles. Particleformation and reactions. Structure and properties of colloidaldispersions.

■ Applied Mathematics and Computational Physics. Supercomputerapplications in fluid mechanics and environmental modeling.Concurrent computing. Asymptotic analyses of transportprocesses.

■ Physics of Complex Fluids. Structures, phase transitions, anddynamics of polymers, liquid crystals, surfactant solutions,and suspensions.

Physical FacilitiesThe chemical engineering laboratories, mainly housed in theEudora Hull Spalding Laboratory of Engineering, are wellequipped. The facilities include experimental reactors, computa-tional facilities, NMR spectrometers, and numerous specialresearch equipment for molecular simulations, DNA synthesis,and electronic, optical, and chemical measurements.

CHEMISTRY

Caltech’s chemistry program offers exciting opportunities for studyand research in many areas of chemical science. Eminent facultyand strong programs are available in chemical synthesis, chemicaldynamics and reaction mechanisms, theoretical chemistry, bio-chemistry, bioinorganic, bioorganic, and biophysical chemistry,materials chemistry, and molecular engineering. Active interaction

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research in biology and chemistry with computer science andapplied and computational mathematics. Research in these areasleading to the Ph.D. may be pursued by entry into one of the rele-vant graduate options in the divisions listed above. The interdisci-plinary nature of biotechnology often includes course work andresearch collaborations that embrace more than one division. Eachgraduate option specifies the emphasis of the educational programand its degree requirements.

Excellent facilities for biotechnology research are available ineach of the participating divisions. For example, the BeckmanInstitute provides extraordinary resources for development andapplication of new instruments and methods.

CHEMICAL ENGINEERING

The chemical engineering faculty teach and conduct research onfundamental chemical, biological, and transport processes and theirapplication in understanding, designing, and controlling a broadspectrum of complex chemical, biochemical, and environmentalprocesses. The faculty and students utilize their analytical skills andlaboratory resources to study diverse processes and to synthesizenew materials. The combination of engineering principles, chem-istry, biology, physics, and mathematics that characterizes chemicalengineering at Caltech enables students and faculty to contributeto the solution of a wide range of critical problems and to aid increating new areas of science and technology.

Areas of ResearchMany different research areas are offered to students seeking thedegrees of Master of Science or Doctor of Philosophy in chemicalengineering. Particular research fields emphasized in the depart-ment include■ Biological Design and Engineering. Engineering of proteins,

metabolic pathways, genetic regulatory networks, and syntheticecosystems by computational and laboratory evolutionapproaches.

■ Fluid Mechanics and Transport Processes. Mechanics of polymericliquids, microstructured fluids, colloidal dispersions, and sus-pensions and granular media. Transport in heterogeneousmedia.

■ Polymer Physics and Chemistry. Molecular understanding ofpolymer melt rheology. Optical properties of polymer blends.Dynamic modeling of polymer structure and rheology. Syn-thesis of tailored polymers by chemical and biological means.

■ Biomaterials. Synthesis and properties of organic materialscompatible for use in living systems.

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als. In these studies, theoretical techniques are being developed toprovide detailed understanding of electron transfer processes, pro-ton transfer reactions, energy randomization processes within mol-ecules, and the dynamics of reacting systems. Computer simula-tions are addressing even more complicated systems, from solid-state materials to complex biomolecules.

Research in biochemistry and molecular biology within thechemistry division exists within the larger framework of biochemi-cal studies at Caltech, and includes crystallographic and spectro-scopic analyses of macromolecule structures; studies on the design,folding, and stability of macromolecules; the mechanisms ofenzyme catalysis and allosteric transitions; interactions betweenproteins and nucleic acids; macromolecular assemblies mediatingreplication and transcription; the role of protein glycosylation inneurobiology; and mechanisms of ion and electron transport inbiological membranes.

Physical FacilitiesThe laboratories of chemistry consist of seven units providingspace for about 25 research groups, including 300 graduate stu-dents and postdoctoral research fellows. Crellin and GatesLaboratories house several research groups, the divisional instru-mentation facilities, and the divisional administrative offices.Synthetic research groups occupy the Arnold and Mabel BeckmanLaboratory of Chemical Synthesis and Church Laboratories. TheBraun Laboratories and the Broad Center house biochemicalgroups and are shared with the Division of Biology. The ArthurAmos Noyes Laboratory of Chemical Physics, one of the majorresearch facilities for chemical physics and inorganic chemistry, isadjoined by the Clifford S. and Ruth A. Mead MemorialUndergraduate Chemistry Laboratory. A number of resource cen-ters serving researchers of the division are located in the BeckmanInstitute.

CIVIL ENGINEERING

Civil engineering includes the research, development, planning,design, and construction associated with urban development, watersupply, energy generation and transmission, water treatment anddisposal, transportation, and space development. Dealing with thefunction and safety of such facilities as buildings, bridges, pipelines,dams, rivers, power plants, and harbors, it is concerned with theprotection of the public against natural hazards such as earth-quakes, winds, floods, landslides, water waves, and fires.

Recent advances in technology, the escalation of urban prob-lems, and the exploration of space have broadened the applications

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Civil Engineering

exists between chemistry and other disciplines at Caltech, especial-ly applied physics, biology, chemical engineering, environmentalengineering, geological and planetary sciences, and materials sci-ence. There is strong interest on the part of the faculty in bothteaching and research, and the undergraduate and graduate pro-grams are designed to encourage the greatest possible amount offreedom, creativity, and flexibility.

Areas of ResearchCaltech has a long and continuing reputation for excellence inchemistry in the areas of molecular structure and the nature ofchemical bonding. Much of the current research in chemistry isdirected at establishing and manipulating the mechanisms of reac-tions of fundamental chemical and biological significance.

Programs in chemical physics emphasize studies of moleculardynamics and structure using techniques that include femtosecondlasers, molecular beams, single-molecule spectroscopy, and ioncyclotron resonance, while novel methods such as ultrafast electrondiffraction and force-detected magnetic resonance are being devel-oped and applied to systems of increasing complexity. In chemicalbiology, research focuses on fundamental issues relevant to biologi-cal electron transfer processes; the chemical basis of synaptic trans-mission by ion channels; analysis of the kinetics, thermodynamics,and mechanism of the sequence-specific ligand binding to DNA;the mechanism of glycosylation in biological systems; and mecha-nistic enzymology. Catalysis by transition metals represents a cen-tral area of research in the inorganic and organometallic areas.Current research interests include the uses of transition metalcomplexes as homogeneous and heterogeneous catalysts for poly-mer synthesis, solar energy conversion and storage, and methaneand water oxidation. Reactions of molecules on surfaces are animportant focus, especially on semiconductors.

In addition to the significant amount of synthetic chemistryinvolved in the above projects, several groups have chemical syn-thesis as a primary research goal. This research includes projectsaimed at the synthesis of complex organic molecules of importancein biology and human medicine. These efforts include develop-ment of new and synthetically useful chemical transformationsmediated by novel organic and transition metal-based catalysts.The division has an exceptional program in polymer science, withemphasis on the development of strategies and methodologies forthe synthesis of designed polymers using chemical and biological-based approaches. On even larger molecular scales, powerfulapproaches are being pursued to fabricate, assemble, and utilizenanometer-scale structures.

The theoretical chemistry program ranges from fundamentalstudies of electron transfer to excited states and reaction dynamicsof small molecules, to simulations of biological systems and materi-

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al brain imaging of subjects engaging in a range of tasks (fromvisual perception to moral decision-making and gambling), andpowerful analytical and numerical methods to model and under-stand complex networks, from protein regulatory networks to thebrain, as well as data flooding in from genomic analysis. Faculty inthe program belong to the Divisions of Biology; Engineering andApplied Science; and Humanities and Social Sciences. They havean interest in developing conceptual frameworks and analyticalapproaches for tackling seemingly disparate problems that share acommon deep structure at the computational level. Students in theprogram will partake of a wide-ranging curriculum that will pro-mote a broad understanding of neurobiology, sensory psychology,cognitive science, computational hardware and software, and infor-mation theory.

Areas of ResearchAreas of research include experimental and modeling studies ofvision and the visual system on the basis of electrophysiology, psy-chophysics, and functional imaging techniques; cognitive psycholo-gy; the analysis of olfactory coding in insects and mammals; thetheory of collective neural circuits for biological and machine com-putations; modeling and representation of physical objects for thegeneral analysis of images; the neuron as a computational device;computational modeling and analysis of information processing inbiochemical and neural networks; the design and use of syntheticmacromolecules as computational devices; the study of evolution innatural and artificial systems; the study of the auditory system ofbirds; learning and plasticity in rodent and human medial temporallobe; memory-related activity in the human hippocampus; visualmotion perception, movement planning, attention, awareness, andconsciousness in the primate brain using a combination of neuro-physiological, psychophysical, and computer modeling techniques;multiunit recordings in behaving animals; neuroprosthetic devicesand recording methods in humans; light and magnetic resonanceimaging of cell lineages, cell migrations, and axonal connections inthe forming nervous system; functional MRI imaging of corticalareas in humans and other primates; design and implementation ofnovel algorithms and architectures that enable efficient fault-toler-ant parallel and distributed computing; and learning theory andsystems, pattern recognition, information theory, and computa-tional complexity.

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Computation and Neural Systems

of civil engineering, increasing the scope of research. New prob-lems have presented special challenges to the civil engineer well-trained in the fundamentals of his or her profession. For this rea-son, in the advanced study of civil engineering at the Institute, theapplication of basic scientific principles and mathematics is empha-sized for the solution of engineering problems.

Areas of ResearchGraduate work leading to advanced degrees lies chiefly in the fol-lowing fields: structural engineering and structural dynamics;applied mechanics; earthquake engineering; soil mechanics andfoundation engineering; finite element analysis; and environmentalengineering (see also environmental science and engineering). Inthe past few years, graduate students and members of the facultyhave pursued a variety of research programs, including the analysisof structures subjected to earthquakes and other dynamic loadings;optimal performance-based structural design; system identificationand control of structures; structural health monitoring; the use offinite element methods for structural analysis; and seismic risk andstructural reliability.

Students whose interests are in environmental problems mayenroll for graduate degrees in either civil engineering or environ-mental science and engineering.

Physical FacilitiesCivil engineering activities are housed in two buildings: theFranklin Thomas Laboratory, which contains the soil mechanicslaboratory and centrifuge, the earthquake engineering researchlaboratory and library, and the vibration laboratory; and the W. M.Keck Engineering Laboratories, which contains the environmentalscience and engineering laboratories. Excellent computing facilitiesare available through the campus computing network and in thespecialized computing centers of various research groups.

COMPUTATION AND NEURAL SYSTEMS

CNS is an interdisciplinary option that studies problems arising atthe interface between molecular, cellular, neural and systems biolo-gy, electrical engineering, computer science, psychology, and cog-nition. The unifying theme of the program is the relationshipbetween the physical structure of a computational system (synthet-ic or natural hardware), the dynamics of its operation, and thecomputational problems that it can efficiently solve. The creationof this multidisciplinary program stems from continuing progresson several fronts: the analysis of neuronal networks using single-and multi-unit recording techniques in behaving animals, function-

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understand quantum, biomolecular, and molecular electronicsubstrates as possible media for future computing machines. Aswas the case with semiconductor electronics, Caltech comput-ing can draw on the world-class expertise of its biology, physics,and chemistry departments as it tackles the many challengingopportunities that these new substrates present.

■ Systematic Design. A key theme in the Caltech computer sciencedepartment is systematic design of systems at all levels. Thisshows up in the design of numerical algorithms for physicalsimulation and computer graphics, design of concurrent anddistributed systems, abstractions for physical computing sub-strates, design of learning systems, the design of programminglanguages, the automated optimization of computations forboth software and hardware implementation, and the controland optimization of networks. The success of computer systemshas allowed the building of systems of unprecedented scale andcomplexity. These systems can only be understood and man-aged if we are careful to contain the complexity involved. Wecan only hope to create and optimize efficient computing arti-facts by systematically defining and exploring their design space.This does not say that system design is not a creative endeavor,but rather that careful design allows us to expose the placeswhere creativity is most needed, and to carefully assess theimpact of new ideas and techniques.

■ Concurrency. The physical world is highly parallel. Caltech com-puter science has embraced concurrency as a fundamental fea-ture of computing systems from its inception. Within thedepartment, parallelism is a theme at all levels, from physicalcircuits, through tightly coupled, concurrent multiprocessors,through distributed systems, up to Internet-wide computingsystems and beyond. Disciplines and systematic design fordefining and managing the potentially complex interactions inparallel systems is a key focus.

■ Robust Modeling of Physical Systems. Caltech computer sciencealso has a unique focus in developing rigorous and robust mod-els of the physical world. These models are mathematically andphysically sound, and serve as a basis for computer graphics andvision research, as well as the simulation of mechanical, optical,and biological systems.

■ Theory. A key component of systematic design is a strong theo-retical understanding, which provides a basis for synthesis,analysis, and verification. The theory of computation focuses ondeep mathematical problems, many of which have substantialtechnological impact. Theory is not relegated to a single groupat Caltech, but rather forms an integral part of all disciplines(learning, VLSI, systems, graphics, programming languages,cryptography, etc.). As such, it has a strong connection to actualpractice in each domain. Theory in computer science at Caltech

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Computer Science

COMPUTER SCIENCE

Although computing is a ubiquitous tool in all areas of study andresearch at Caltech, computer science is directed at the theory andtechnology of computation itself. Computer science is the study ofinformation, and of the structures that communicate, store, andprocess information. Whether these structures are expressed inhardware and called machines, in software and called programs, orin nature or society, the fundamental concepts are similar. The stu-dent of computer science at Caltech does not specialize along tra-ditional lines that divide hardware and software, systems and appli-cations, or theory and experiment. Rather, a unified approach tothe design and analysis of computing structures is taken both incourses and in research.

Unlike the study of physical and natural sciences, the objectsof study by computer scientists are artificial systems; that is, struc-tures that are purposefully designed, taking into account con-straints imposed by our building blocks in the physical world andfundamental requirements of the computation itself. Thus, designassumes a role equal in importance to analysis, and is a term foundfrequently in the curriculum and research. Design is not only acreative activity but is also formal and systematic. Managing thegreat complexity of useful systems requires that one representcomputations in a way that is amenable to mathematical treatment,as well as to implementation.

Areas of ResearchResearch and advanced courses leading to the Ph.D. degree incomputer science are concentrated in the following areas: VLSIsystems; quantum and molecular computation; computer architec-ture; parallel and distributed computation; theory of computation;programming languages; semantics; programming methods andcorrectness; information theory; machine learning and computa-tional finance; computer vision; computer graphics; computer-aided design; and networking. Research projects frequently involvework in several of these areas, with both the theoretical and experi-mental aspects, as well as connections with such fields as mathe-matics, physics, biology, economics, and electrical engineering.■ Physical Implementation of Computations. Computations must ulti-

mately be implemented in some physical medium (e.g., semi-conductor electronics, DNA self-assembly, quantum states ofelementary particles, molecular electronics). Developing robustdisciplines, abstractions, and methodologies that allow thedesign of reliable computing substrates has been a focus of thedepartment since its inception. Caltech has been a leader in thedevelopment, engineering, and design of very large scale inte-grated (VLSI) circuits, and this remains a core part of theresearch and education. Beyond VLSI, efforts are under way to

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meet the challenge of educating students both in the mathematicalmethods of control and dynamical systems theory and their appli-cations to engineering problems.

Automatic control is an enormously successful field that affectsevery aspect of our lives. A combination of technological develop-ments, economic pressures, and research advances has promotedcontrol into a central position in technology, and over the nextseveral decades, the impact of automatic control systems willcontinue to grow. The applications we have seen so far—such ascheap and fast computer disk drives, active vehicle suspension con-trol, fly-by-wire aircraft, highly integrated manufacturing facilities,and manned and unmanned space systems—are only the beginningof this trend.

The rapid development of dynamical systems theory as an intel-lectual discipline over the past 10 years has been equally striking.Stimulated by the discovery of the phenomenon of “deterministicchaos,” the “dynamical systems approach” has been adopted in avariety of diverse engineering disciplines (e.g., chemical, mechani-cal, electrical, civil, and aeronautics), as well as the physical, biolog-ical, and social sciences. At the same time, dynamical systems con-tinues to enjoy strong links with pure and applied and computa-tional mathematics.

While research in both control and dynamical systems is inher-ently interdisciplinary and crosses many traditional engineeringand scientific boundaries, their relationship is much deeper. Astheoretical disciplines, they are moving together rapidly. Themathematical background required to do research in either controlor dynamical systems is nearly identical and can be difficult toobtain within traditional curricula in engineering and mathematics.The CDS option provides a coherent and complete graduate cur-riculum with corresponding research opportunities, both theoreti-cal and applied.

Areas of ResearchTheoretical research is conducted in all aspects of control, withemphasis on robustness; multivariable and nonlinear systems; opti-mal control; decentralized control; modeling and system identifica-tion for robust control; control of Hamiltonian and Lagrangiansystems; and control of nonholonomic mechanical systems.Techniques from operator theory, differential geometry, dynamicalsystems, and computer science are combined to study controlproblems in a wide variety of areas. A central theme is the roleof uncertainty and robustness, and the development of a unifiedtheory for modeling, system identification, analysis, and synthesisof nonlinear control systems.

The CDS research program in nonlinear dynamics has twocomponents: one mathematical and the other driven by specificareas of applications in science and engineering. The main thrustof the mathematical research is to develop mathematical methods

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Control and Dynamical Systems

includes traditional fields such as complexity analysis andsemantics, and also theories of numerical computation, opti-mization, probability, and game theory.

■ Interdisciplinary Research. Computation enables better controland understanding of the physical world. These are ubiquitousthemes at Caltech. We’ve already noted the intimate way inwhich computer science interacts with the physical sciences tophysically build computations. Computer simulations, model-ing, and analysis are now key enablers, allowing all fields of sci-ence to advance rapidly. Modern mechanical and aeronauticalsystems are enabled by vast computational processing for sens-ing and control. Further, insights into computational manage-ment of information helps us understand information process-ing issues in natural systems (e.g., cells and neurons) and buildhypothetical models that advance our understanding of naturalcognition. Economic analyses play an important role in thedesign of computing systems and, in addition, research oninformation systems impacts business and economics. Theserelations provide many opportunities for scholars in computerscience to work closely with colleagues throughout Caltech.The centers for information science and technology facilitateinterdisciplinary research (see http://www.ist.caltech.edu).

Physical FacilitiesThe computer science department has excellent computing facili-ties ranging from high-performance workstations to multiproces-sors and supercomputers. The inventory of computers is upgradedfrequently, and students have easy access to state-of-the-art equip-ment. The department has two semi-immersive 3-D displays andnumerous graphics workstations, and it maintains VLSI laborato-ries equipped with complete facilities for the construction and test-ing of experimental systems. The department maintains severallaboratories open to students and has a wide collection of softwarefor a range of applications. The Institute libraries maintain a largecollection of journals in computer science and related fields.

CONTROL AND DYNAMICAL SYSTEMS

Some of the most exciting interactions between mathematics andengineering are occurring in the area of analysis and control ofuncertain, multivariable, and nonlinear dynamical systems. Whilechanging technology has made control and dynamical systems the-ory increasingly relevant to a much broader class of problems, theinterdisciplinary nature of this area means that it no longer has anatural home exclusively or even primarily within any one of thetraditional engineering disciplines. The CDS option is designed to

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electronics and electronics, ultrafast (

forms. Digital filter banks, digital communication systems,multidimensional multirate signal processing. Image process-ing, digital halftoning, and denoising.

10. Computational Vision (Perona)—Theoretical and experimentalresearch on the computational principles underlying visionprocesses. Psychophysics and modeling of the human visualsystem. Theory and applications of computer vision. Currentemphasis on visual object recognition; vision-based human-computer interfaces; perception and modeling of humanmotion and activities; 3-D photography, perception, and mod-eling of shapes. Areas of collaboration include learning theory,computer graphics, neurophysiology, psychology, applied prob-ability, robotics, geometry, and signal processing.

11. Nanofabrication and Design of Ultrasmall Devices (Scherer)—High-resolution lithography and dry etching allow the minia-turization of structures to below 10 nanometers. Using thesetechniques, ultrasmall optical, magnetic, and fluidic structurescan be constructed. Current research includes the design andfabrication of nanocavity lasers; photonic-crystal waveguidesand modulators; nanomagnet arrays; nonmechanical oscillators;and microfluidic pumps, valves, and networks on biochips.

12. Distributed Information Systems (Bruck)—Theoretical and exper-imental research on a number of fundamental issues related tonovel algorithms, protocols, and architectures that enable thecreation of reliable and scalable distributed computing, com-munications, and storage systems. Past projects include RAIN(Reliable Array of Independent Nodes) that focused on cre-ation of reliable space-borne systems in collaboration withNASA/JPL. The RAIN technology resulted in a spin-off,called Rainfinity (www.rainfinity.com) that is focusing on creat-ing software for Internet reliability. The current key project inthe lab focuses on fundamental issues associated with the infra-structure for wireless Internet. The project called MANGO(Mobile Array of Network Gateways) is part of the Caltech’sLee Center for Advanced Networking. More information canbe found at http://paradise.caltech.edu.

13. Data Compression (Effros)—Theoretical analysis and practicaldesign of algorithms for efficiently representing informationfor communication, storage, and processing. Current workfocuses on the special challenges introduced by emergingapplications such as network communication systems. Exam-ples of areas of investigation include the theory and practice ofoptimal data compression for systems containing multipleencoders, multiple decoders, or both, and adaptive or universalcompression systems. Results range from theoretical perfor-mance bounds to practical coding algorithms. Tools useful tothese investigations include information theory, probabilitytheory, graph theory, optimization, and signal processing.Possible areas of collaboration include networking, distributed

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Electrical Engineering

5. Wireless Engineering (Hajimiri, Rutledge)—Circuits and systemdesign for wireless communication using integrated circuittechnology, including analysis and design of communicationbuilding blocks, such as monolithic low-noise amplifiers(LNA), active and passive mixers, local oscillators and frequen-cy synthesizers, frequency dividers and multipliers, poweramplifiers, integrated filters, intermediate frequency amplifiers,and baseband digital signal processing. These building blocksare used in the design of complete transceiver circuits with newarchitectures for various applications. The group also has inter-ests in devices for radar, remote sensing, broadcasting, andindustrial power from 1MHz to 1THz. Current projectsinclude phased-array radars, quasi-optical amplifiers and oscil-lators for millimeter-waves, multiplier grids for 1THz andhigh-frequency Class-E amplifiers. For more information seehttp://mmic.caltech.edu.

6. Learning Systems and Computational Finance (Abu-Mostafa)—The Learning Systems Group at Caltech studies the theory,algorithms, and applications of automated learning. The theoryof learning uses mathematical and statistical tools to estimatethe information (data and hints) needed to learn a given task,and the computational aspects of learning. The algorithms dealwith learning mechanisms in different models, such as neuralnetworks, and different learning protocols. The applications oflearning are very diverse. The group has emphasized computa-tional finance applications, where learning is used in financialforecasting, risk analysis, and derivative pricing. Other recentapplications include pattern recognition and medical diagnosis.

7. Optical Information Processing (Psaltis)—Research to developoptical techniques and devices for information processing.Current areas of interest include holography, optical networks,optical memories, optical sensors, image processing, and pho-torefractive materials.

8. Microsensors and Microactuators (Tai)—Silicon micromachiningtechnology is used to fabricate miniature solid-state micro-electromechanical devices. Current research includes pressuresensors, flow sensors, IR sensors, accelerometers, microphones,micromotors, microvalves and micropumps, neuro-probes, andmicrosurgical tools. Device research requires broad exercisecovering physics, design, fabrication, and testing. Hands-ontraining is especially emphasized in the MicromachiningLaboratory.

9. Digital Signal Processing (Hassibi, Vaidyanathan)—Theoreticaland computer oriented work on a wide variety of problems indigital signal processing. Multirate systems and filter banks,wavelets, filter design, quantization in signal processors, adap-tive signal processing, statistical signal processing, robust filter-ing, multidimensional multirate systems, and wavelet trans-

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interactions and synchronizations. The other major researchfocus is on the development of the next generation of opticalcoherence tomography systems that will have contrast agentimaging capability, greater sensitivity, and improved acquisi-tion rates.

ENVIRONMENTAL SCIENCE AND ENGINEERING

This interdisciplinary graduate program is concerned with earthsystem science and engineering. Complete information is availableat http://www.ese.caltech.edu.

At the heart of the ESE program are three core areas ofresearch expertise: environmental physics, environmental chem-istry, and environmental biology. Research and instruction empha-size basic scientific studies that underlie new solutions to challeng-ing environmental problems from atomic to global scale. Theseinclude urban, regional, and global air quality; water supply andwater quality control; hazardous waste treatment; microbial ecolo-gy; and global environmental and climate change.

Among the academic disciplines central to the program areatmospheric and aquatic chemistry; environmental fluid mechanics;environmental and geochemical microbiology; dynamic meteorolo-gy; oceanography and hydrology; aerosol physics and chemistry,chemical reaction engineering, and chemical kinetics and photo-chemistry. Courses are offered in the environmental science andengineering program and in other related programs of theInstitute. Faculty members participating in this interdisciplinaryprogram are from the Divisions of Engineering and AppliedScience, Chemistry and Chemical Engineering, and Geologicaland Planetary Sciences.

Areas of ResearchExamples of recent and current research are theoretical and experi-mental studies on trace elements and individual chemical com-pounds in the environment; chemistry of the mineral-water inter-face; coagulation and filtration of particles; advanced oxidationprocesses for water treatment; biogeochemical cycling of arsenic;disinfection of water; aerosol chemistry and physics; cloud chem-istry and global climate change; measurement of free radicalspecies in the stratosphere and upper troposphere; photochemistryof important trace gases; novel treatment processes for hazardousmaterials; e.g., ultrasound, pulsed-power plasmas, semiconductorphotochemistry; environmental photochemistry; oxidation process-es in aqueous systems; pollutant and particle transport in alluvialstreams and groundwaters; studies of the emissions sources andfate of organic chemicals in the atmosphere; regional air pollution

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Environmental Science and Engineering

computing, communications, wireless communications, con-trols, digital signal processing, and computational vision.

14. Integrated Circuits (Hajimiri)—Analysis, design, simulation,verification, and testing of integrated circuits for variousapplications, such as high-speed and wireless communications,wireless local-area networks, highly stable frequency sources,distributed integrated circuit design techniques for ultrahigh-speed silicon-based circuits, system and circuit design formultiband systems, single-chip spectrum analyzers, perfor-mance limitation of A/D and D/A data converters, and robustcircuit design techniques. Projects also include modeling of theeffect of substrate and supply noise in large integrated circuitsand design techniques to minimize their effect, examination ofintegrated passive structures and their fundamental perfor-mance limits, and noise modeling in amplifiers, mixers, andoscillators. More information can be found at http://www.chic.caltech.edu.

15. Networking (Low)—Modeling, analysis, control, optimization,simulation, and implementation of networks and protocolsand networked computing. Current research focuses oncongestion control, active queue management, multicast, webperformance, resource allocation, and fundamental issues innetworked computing, control, and communication. Moreinformation at http://netlab.caltech.edu.

16. Wireless Communications (Hassibi)—Theoretical research onlink, system, and network aspects of wireless communications.Current areas of interest include time-varying channel model-ing; capacity computations for wireless channels; channel esti-mation, identification, and equalization; multiple-antennasystems and diversity techniques; space-time codes; modulationtechniques; channel access and spectral sharing through variousTDMA, FDMA, CDMA, and hybrid techniques; multiuserdetection and interference cancellation; dynamic channel allo-cation; models and performance analysis of wireless networks;ad hoc networks; signal processing for wireless. The researchencompasses various areas of information theory, coding theo-ry, stochastic processes, statistical and adaptive signal process-ing, and network theory.

17. Biophotonics (C. Yang)—Experimental research on optical imag-ing and extraction of information from biological targets byexploiting the different interaction mechanisms of light withbiological materials. Primary research interest focuses on theapplication of novel interferometric and nonlinear opticalprocesses for nondestructive biomedical imaging. One presentobjective research is to use low-coherence interferometricphase technique to probe the small (nanometer-scale) andslow (nanometer/second) dynamics of living cells, and tostudy the physical response of cells to subtle changes in theirenvironment and the physical manifestation of cell-to-cell

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The environmental chemistry and aquatic chemistry laborato-ries and the Environmental Analysis Center are equipped forchemical analysis by electrochemistry, plasma emission mass spec-trophotometry, gas chromatography, high-performance liquidchromatography, fluorescence spectroscopy, infrared spectrometry,gas chromatography–mass spectrometry (GC-MS), liquidchromatography–mass spectrometry (LC-MS), high-resolutionMS/MS/MS, ATR-FTIR, electrospray mass spectrometry, super-critical fluid extraction (SCF/MS), multicomponent UV-visiblespectrophotometry, electrophoresis chromatography, gradient-elution ion chromatography, gel permeation chromatography, totalorganic carbon analysis, and, for physical characterization of aque-ous particles by light scattering, electrophoresis and electrical par-ticle size analysis. The Environmental Analysis Center operates 14mass spectrometry systems.

The atmospheric photochemistry laboratory has a numberof lightsources and detectors for investigation of atmosphericchemistry. Instrumentation development activities include designof optical and mass spectrometers for environmental analyticalchemistry.

The environmental microbiology laboratory includes a facilityfor the preparation of bacterial media, as well as equipment for theisolation, cultivation, and physiological characterization of fastidi-ous and anaerobic microbes, DNA isolation and manipulation,DNA sequence data manipulation and analysis, protein purificationand enzyme assays, and culture field analyses. In addition, access isavailable to several electron microscope facilities on campus, aswell as the oligonucleotide probe synthesizer and the microproteinsequenator.

The option provides students with access to scientific comput-ing and word processing through various departmental and person-al computers and advanced supercomputers operated by theInstitute.

GEOLOGICAL AND PLANETARY SCIENCES

Students and faculty in the Division of Geological and PlanetarySciences study the earth and planets to understand their origin,constitution, and development, and the effect of the resulting phys-ical and chemical environments on the history of life, and onhumanity. The approach to these problems relies strongly on thebasic sciences. Programs of study and research are pursued in envi-ronmental science and engineering, geology, geobiology, geochem-istry, geophysics, and planetary science. The curriculum is flexibleso that students with degrees in biology, chemistry, engineering, orphysics may carry out graduate work within the division. Inter-disciplinary studies are encouraged and students may carry out

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Geological and Planetary Sciences

modeling and control; global-scale modeling of troposphericchemistry and the carbon cycle; marine geochemistry; geochemicalstudies of paleo ocean circulation; trace-gas geochemistry; microbi-ology of arsenic in natural waters; microbiology of iron-reducingorganisms; termite-microbe symbiosis and its impact on trace-gasdynamics; cultivation of novel microbes with novel properties;antagonistic interactions among competing soil microbes.

Physical FacilitiesThe laboratory experimental work in environmental science andengineering is carried out across the Caltech campus with a widevariety of modern instrumentation in the various laboratoriesdescribed below.

The atmospheric chemistry and aerosol laboratory includes astate-of-the-art facility located on the roof of the Keck Laboratorythat has been specially designed for studies of the photochemicalreactions of gaseous and particulate pollutants. Dual 28 m3 indoorirradiated reaction chambers are used for direct simulations ofatmospheric conditions using carefully prepared mixtures of hydro-carbons, nitrogen oxides, and aerosols. Both gas-phase chemistryand the formation of aerosol particles are probed with this system.

Analytical instrumentation includes monitors for major gas-phase trace gases, gas chromatography, gas chromatography withmass spectrometry, and the resources of the EnvironmentalAnalysis Center for detailed chemical analysis of gas and aerosolsamples. Measurements of aerosol particle formation and growthin the smog chamber experiments and in field studies are per-formed using the scanning electrical mobility spectrometer, a fast-response, high-resolution particle-sizing instrument developed atCaltech, along with more conventional particle measurement tech-niques (optical particle counters, cascade impactors, condensationnuclei counters, and filter samplers). A novel aerosol mass spec-trometer is used for molecular speciation of aerosols.

Flow reactors are used for controlled studies of nucleationprocesses, and to probe the dynamics of agglomerate aerosols.Equipment is available sufficient to conduct field experimentsinvolving the measurement of atmospheric particulate matter con-centration, chemical composition and size distribution, and gaseouspollutant concentration, simultaneously at up to 10 monitoringsites.

Caltech, in conjunction with the Naval Postgraduate School inMonterey, California, operates the Center for InterdisciplinaryRemotely Piloted Aircraft Studies. This center operates researchaircraft for atmosphere science studies, including a Twin Otter air-craft instrumented to carry out state-of-the-art measurements ofatmospheric aerosol and cloud properties and composition. Caltechfaculty and graduate students regularly participate in large, interna-tional field programs in atmospheric chemistry and aerosols usingthe aircraft available in the Center.

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Physical FacilitiesThe division is housed in three adjacent buildings, which are wellequipped for modern instruction and laboratory work. They con-tain several comfortable seminar rooms and the library as well asstudent and faculty offices. Numerous computers are distributedthroughout the division, including a facility for geographic infor-mation systems, remote sensing, and 3-D modeling. There is ananalytical facility, which includes an electron microprobe and ascanning electron microscope. Rock and mineral collections andsample preparation areas are available. There are modern laborato-ries for the chemical analysis of solids, liquids, and gases. A varietyof mass spectrometers (electron impact, thermal ionization, laserablation, and inductively coupled plasma) provide analyses at thetrace and ultralow levels. Optical, infrared, and Raman spectro-scopies are available for the characterization and analysis of sam-ples. State-of-the-art tunable laser spectrometers are available forthe study of gas phase and surface processes of importance in cos-mochemical and geochemical environments. This facility is used tostudy the mechanisms of chemical reactions that govern the forma-tion of the protosolar nebula and the earth’s upper atmosphere.Laboratories for experimental petrology contain high-temperaturefurnaces and presses for work up to 25 GPa. In addition, there is alaboratory for the study of the behavior of rocks and minerals andtheir elastic constants in the pressure and temperature environ-ments of planetary interiors. This includes a shock-wave laboratoryfor studying ultrahigh-pressure equations of state and shockeffects. Cooperation with other divisions on campus providesaccess to additional instrumentation for sample preparation andanalysis; see the Catalog sections for materials science and environ-mental science and engineering.

A laboratory for molecular geobiology specializes in the cultur-ing and the biochemical and genetic study of anaerobic bacteria. Asensitive magnetometer facility is designed for the study of bothbiomagnetism and paleomagnetics.

The Seismological Laboratory of the Institute is housed in theSeeley G. Mudd Building. This has excellent computer facilitiesand maintains a seismological observatory, which includes theKresge Laboratory, located about three miles west of the campuson crystalline bedrock, affording a firm foundation for the instru-ment piers and tunnels. The Seismological Laboratory carries on avigorous program of geophysical research and education and isheadquarters for a modern 200-station broadband array calledTriNet. This array provides an excellent research facility for thestudy of earthquakes and earth structure.

The Jet Propulsion Laboratory, NASA’s lead center for plane-tary exploration, is located seven miles from campus and is admin-istered by the Institute. Students and faculty participate in JPLactivities through joint research, instrument development, mission

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Geological and Planetary Sciences

academic and research programs within and between differentdivisions.

The geographical position and geologic setting of the Instituteare favorable for year-round field access to a wide variety of earthproblems and materials. Current advances in understanding thedynamic motions of the earth’s crust and the structure of the inte-rior have opened new opportunities for research into the processesresponsible for the earth’s development and activity. Seismic activi-ty in the Southern California area presents stimulus and researchmaterial for the study of earthquakes, which are of great practicalconcern and are intimately related to the earth’s development on aglobal scale. Human records of seismic activity are put into long-term perspective by studies of surface and bedrock geology, whichreveal the history of motion on fault systems. The dynamics andgeometry of crustal movements are studied by geological and geo-physical methods on both planetary and local scales in order tounderstand the evolution of continents. Major processes and eventsin the chemical and physical evolution of the earth can be identi-fied by studying the structure of rocks formed or modified in theseevents, and their chemical and isotopic compositions. These geo-logical events and conditions have been intimately associated withthe origin and evolution of life on Earth. The field of geobiologyuses both geological and genetic evidence to examine the impact oflife on the earth and the impact of geological conditions on biolo-gy. The absolute chronology can be established by measurementsof radioactive isotopes. A wide variety of studies focuses on the ori-gins of igneous and metamorphic rocks in planetary interiors.These include radiogenic and stable isotopes and experimentalpetrology, in addition to field and petrographic studies. The broad-scale structure of the earth is inferred from isotopic-geochemicalstudies and is inter-related with geophysical studies. Furtherbreadth in our understanding of the earth and its place in the cos-mos is being gained by the comparative study of the other plan-ets—their atmospheres, surfaces, and internal structures. The earlyhistory of the solar system can be approached by studies of lunarsamples and meteorites. The earliest solar and presolar history isbeing studied by seeking the connection between the residual plan-etary materials and the physical-chemical processes within the solarnebula and the precursor interstellar medium.

Conditions for field study and research in the earth sciences inSouthern California are excellent. A great variety of rock types,geologic structures, active geologic processes, physiographic forms,and geologic environments exist within convenient reach of theInstitute. The relatively mild climate permits field studies through-out the year; consequently, year-round field work is an importantpart of both the educational and research programs. There areactive field programs in diverse areas in North America andthroughout the world.

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the neurosciences. Members of the faculty have a variety of otherinterests, including philosophical logic, moral psychology, and thehistory of philosophy. Courses in English, history, and philosophyare given at both introductory and advanced levels.

A variety of courses in classical and modern European lan-guages and in music and art history are available. Art historyclasses make use of the resources of the Huntington Library, ArtCollections, and Botanical Gardens; the Los Angeles CountyMuseum of Art; and other museums in the area.

Areas of ResearchThe English faculty, interested in new approaches to studying theirsubject, engage in research into the relationships between literatureand the pictorial arts, literature and history, and the material pro-duction of literature.

Research in history covers a wide range of historical fields andmethodologies. Topics include an examination of the developmentof racial attitudes and behavior in the 19th-century United States;the history of the physical and biological sciences and of science inrelationship to society; history and film; and political and economicdevelopment in early modern Europe. A number of faculty carryout research and teaching in the interrelated subjects of science,ethics, and public policy.

Research in philosophy includes work in philosophy of science,philosophy of mind, history of philosophy, ethics, and politicalphilosophy.

INDEPENDENT STUDIES PROGRAM

Independent Studies is an educational alternative for undergradu-ates whose goals cannot be satisfied with a normal undergraduateoption. The student gathers a three-person faculty committee,representing at least two divisions of the Institute, and chooses hisor her own scholastic requirements under this committee’s super-vision. Approval must also be obtained from the CurriculumCommittee, a standing committee of the faculty. The independentstudies program has no facilities of its own. Areas of study andresearch may be selected from any part of the Institute. (For acomplete description see page 214.)

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Independent Studies Program

operations, and data analysis. Planetary science minicomputers andimage processing systems are linked, through the campus network,to the Image Processing Laboratory at JPL and to supercomputersacross the country. In addition, Caltech owns and operates severaloptical and radio observatories that are used partly for planetaryresearch. Active programs of planetary studies are pursued at theOwens Valley Radio Observatory, Palomar Mountain, and theKeck Telescopes.

HISTORY AND PHILOSOPHY OF SCIENCE

The program in history and philosophy of science is devoted to thestudy of the historical evolution and philosophical underpinningsof the physical and biological sciences. Work in history and phi-losophy of science may be pursued as an undergraduate option, agraduate minor, or on a course-by-course basis.

Historical research in the program includes the origins ofexperimental practice, the social and institutional contexts of sci-ence, the origins and applications of quantitative methods, specificdevelopments since antiquity in physics, biology, and chemistry, aswell as biographical and comparative studies. Philosophicalresearch in the program deals with issues in causation, explanation,scientific inference, the foundations of probability and decisiontheory, philosophy of mind, psychology and neuroscience, and sci-entific fraud and misconduct.

HUMANITIES

English at Caltech spans the major periods of American and Britishwriting. Students can pursue interests ranging from Shakespeareand a survey of drama to romantic and modern poetry; from earlyfiction to the postmodern novel.

History at Caltech examines the Western and non-Western pastto understand the evolution of culture, science, institutions, andbehavior. Courses span the medieval, Renaissance, and modernperiods; the United States, Europe, and Asia; and special topicssuch as radicalism and demography. In certain courses, quantitativemethods drawn from the social sciences are applied to historicalstudies.

Philosophy is concerned with the most fundamental issuesinvolving the nature of the world and of human knowledge, values,and judgment. At Caltech, particular emphasis is placed on philos-ophy of the natural and social sciences, scientific inference, moraland political philosophy, and philosophy of mind, psychology, and

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MATHEMATICS

Areas of ResearchStudents in mathematics have the opportunity to work in manyfields of current research. The main active areas of research by thefaculty include the following:■ Algebra. Finite group theory, algebraic group theory, represen-

tation theory, symmetric

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