California Institute of Technology Division of Physics, Mathematics and Astronomy
Overview
Works: 
1,871
works in
2,090
publications in
1
language and
2,261
library holdings

Genres: 
Academic theses
Observations

Classifications: 
QC179,
523.844 
Most widely held works about
California Institute of Technology
Most widely held works by
California Institute of Technology
Magnetohydrodynamic turbulence by Jason Maron (
Archival Material
)
2
editions published
in
2001
in
English
and held by
3
libraries
worldwide
We simulate incompressible, MHD turbulence using a pseudospectral code
Controlling quantum information by Andrew J Landahl (
Archival Material
)
2
editions published
in
2002
in
English
and held by
3
libraries
worldwide
"Quantum information science explores ways in which quantum physical laws can be harnessed to control the acquisition, transmission, protection, and processing of information. This field has seen explosive growth in the past several years from progress on both theoretical and experimental fronts. Essential to this endeavor are methods for controlling quantum information. In this thesis, I present three new approaches for controlling quantum information. First, I present a new protocol for continuously protecting unknown quantum states from noise. This protocol combines and expands ideas from the theories of quantum error correction and quantum feedback control. The result can outperform either approach by itself. I generalize this protocol to all known quantum stabilizer codes, and study its application to the threequbit repetition code in detail via Monte Carlo simulations. Next, I present several new protocols for controlling quantum information that are faulttolerant. These protocols require only local quantum processing due to the topological properties of the quantum error correcting codes upon which they are built. I show that each protocol's faultdependence behavior exhibits an orderdisorder phase transition when mapped onto an associated statisticalmechanical model. I review the critical error rates of these protocols found by numerical study of the associated models, and I present new analytic bounds for them using a selfavoiding random walk argument. Moreover, I discuss faulttolerant procedures for encoding, errorcorrection, computing, and decoding quantum information using these protocols, and calculate the accuracy threshold of faulttolerant quantum memory for protocols using them. I end by presenting a new class of quantum algorithms that solve combinatorial optimization problems solely by measurement. I compute the running times of these algorithms by establishing an explicit dynamical model for the measurement process. This model, the digitized version of von Neumann's measurement model, is recognized as Kitaev's phase estimation algorithm. I show that the running times of these algorithms are closely related to the running times of adiabatic quantum algorithms. Finally, I present a twomeasurement algorithm that achieves a quadratic speedup for Grover's unstructured search problem."
Ultrahigh and microwave frequency nanomechanical systems by Xue Ming Henry Huang (
Book
)
1
edition published
in
2004
in
English
and held by
3
libraries
worldwide
Nanodevices that operate with fundamental frequencies in the previously inaccessible microwave range (greater than 1 gigahertz) have been constructed. Two advances have been crucial to breaking the 1GHz barrier in nanoelectromechanical systems (NEMS): the use of 3Csilicon carbide epilayers, and the development of balanced, high frequency displacement transducers. This achievement represents a significant advance in the quest for extremely high frequency nanoelectromechanical systems
Brane models and the hierarchy problem by Walter D Goldberger (
Archival Material
)
2
editions published
in
2001
in
English
and held by
3
libraries
worldwide
"It has been recently proposed that higherdimensional field theory models in the presence of extended defects ("branes") may play a role in addressing the gauge hierarchy problem. In this thesis we consider several aspects of such field theories. First we perform the KaluzaKlein reduction of a bulk scalar field propagating in the scenario of Randall and Sundrum, which consists of a region of fivedimensional antideSitter space bounded by two threebranes. We then propose a simple mechanism, based on the dynamics of a bulk scalar field, for stabilizing the modulus field (the "radion") corresponding to the size of the compact dimension in the RandallSundrum scenario. Some implications of this stabilization mechanism for lowenergy phenomenology are described. Next, we investigate the oneloop quantum corrections to the radion effective potential. We show that for large brane separation, the quantum effects are power suppressed and therefore have a negligible effect on the bulk dynamics once a classical stabilization mechanism is in place. Finally, we study the ultraviolet divergence structure of field theory in the presence of branes and find that branelocalized divergences arise both at the classical and quantum level. We show how to interpret the classical divergences by the usual regularization and renormalization procedure of quantum field theory."
The arithmetic and geometry of a class of algebraic surfaces of general type and geometric genus one by Christopher M Lyons (
Archival Material
)
2
editions published
in
2010
in
English
and held by
3
libraries
worldwide
Bridging the gap elusive explosions in the local universe by Mansi M Kasliwal (
file
)
2
editions published
in
2011
in
English
and held by
3
libraries
worldwide
"For centuries, we have known that our dynamic universe is adorned by cosmic fireworks: energetic and ephemeral beacons of light from a single star that are a million (nova) to a billion (supernova) times brighter than our sun. However, it had been an ageold conundrum that the brightest nova is approximately 1000 times fainter than the faintest supernova; why should nature leave such a wide "gap"? In search of an answer, I undertook three systematic surveys for my thesis. Since I was looking for transients fainter, faster and rarer than supernovae, I focused my search on galaxies in the local universe. We now have convincing evidence of multiple, distinct populations of rare transients bridging this "gap". Perhaps, we are witnessing new stellar physics  shell detonations in ultracompact white dwarf binaries, electroncapture supernovae, white dwarfs collapsing into neutron stars and birth of blackholes. A small number of intensively followedup discoveries of elusive transients sets the stage for population studies with the upcoming "Large Synoptic Survey Telescope". This effort works towards building a complete inventory of transients in the local universe (d <200 Mpc). It better prepares us for the search for potential electromagnetic counterparts to events in the emerging fields of gravitational wave, neutrino and ultra high energy cosmic ray astronomy as these experiments are also limited to the local universe."
The radio variability of gammaray blazars by Joseph Lee Richards (
file
)
2
editions published
in
2012
in
English
and held by
3
libraries
worldwide
The energetics and environments of Swift gammaray bursts by Stephen Bradley Cenko (
Book
)
1
edition published
in
2009
in
English
and held by
3
libraries
worldwide
Signal extraction and optical design for an advanced gravitational wave interferometer by James E Mason (
Archival Material
)
2
editions published
in
2001
in
English
and held by
3
libraries
worldwide
"The LIGO project is two 4 km baseline interferometers which are currently being constructed in the quest to directly detect gravitational radiation. Concurrent with this effort is research aimed at increasing the strain sensitivity of the initial interferometers to 2.5 x 10⁻²³/[square root]Hz. The optical configuration, which defines the detector gain and bandwidth, is one such area of research. Resonant sideband extraction (RSE) is the configuration which is proposed for advanced LIGO. RSE allows for much more freedom in the optimization of the detector response compared to the initial configuration. The principle of RSE is examined in the context of a three mirror coupled cavity. The effect of optical losses on the design of an RSE interferometer is discussed. Two model optimizations of the interferometer design are done: one for binary inspiral sources and one for periodic sources at 1 kHz. An optical heterodyne signal extraction scheme is proposed to sense the deviation of the mirrors away from their nominal positions, and to read out the gravitational wave signal. The scheme is applied to the two model interferometers previously designed, and its performance is analyzed for each case. Allowable residual deviations of the common mode degrees of freedom are also derived. A tabletop prototype of an RSE interferometer has been constructed to demonstrate both the viability of the proposed signal extraction scheme and the tunability of the RSE interferometer. Good agreement on both counts is found between the measured experimental data and the modeled predictions. The coupling of laser frequency and amplitude noise into the gravitational wave readout port is analyzed for the RSE configuration assuming the proposed gravitational wave signal readout scheme. Specifications for the allowable laser frequency and amplitude noise, as well as allowable residual deviations of the differential mode degrees of freedom, are derived for the two model interferometers."
Experiments with a laser interferometric gravitational wave antenna by Michael Edward Zucker (
Book
)
3
editions published
in
1989
in
English
and held by
3
libraries
worldwide
Nuclear reactions with a proton magnetic spectrograph by Cheng Wu Li (
Book
)
3
editions published
in
1951
in
English
and held by
3
libraries
worldwide
Diffusion in amorphous media by Mihail S Iotov (
Book
)
2
editions published
in
1998
in
English
and held by
3
libraries
worldwide
Nonlinear, coupled, and parametric nanoelectromechanical systems by Inna Kozinsky (
Book
)
3
editions published
between
2007
and
2008
in
English
and held by
3
libraries
worldwide
Special Frobenius traces in Galois representations by Liubomir Chiriac (
Archival Material
)
2
editions published
in
2015
in
English
and held by
2
libraries
worldwide
This thesis studies Frobenius traces in Galois representations from two different directions. In the first problem we explore how often they vanish in Artintype representations. We give an upper bound for the density of the set of vanishing Frobenius traces in terms of the multiplicities of the irreducible components of the adjoint representation. Towards that, we construct an infinite family of representations of finite groups with an irreducible adjoint action. In the second problem we partially extend for Hilbert modular forms a result of Coleman and Edixhoven that the Hecke eigenvalues ap of classical elliptical modular newforms f of weight 2 are never extremal, i.e., ap is strictly less than 2[square root]p. The generalization currently applies only to prime ideals p of degree one, though we expect it to hold for p of any odd degree. However, an even degree prime can be extremal for f. We prove our result in each of the following instances: when one can move to a Shimura curve defined by a quaternion algebra, when f is a CM form, when the crystalline Frobenius is semisimple, and when the strong Tate conjecture holds for a product of two Hilbert modular surfaces (or quaternionic Shimura surfaces) over a finite field
Topological quantum field theory and the geometric Langlands correspondence by Kevin Setter (
Book
)
2
editions published
in
2013
in
English
and held by
2
libraries
worldwide
Biophysical and network mechanisms of high frequency extracellular potentials in the rat hippocampus by Erik W Schomburg (
Archival Material
)
2
editions published
in
2014
in
English
and held by
2
libraries
worldwide
A fundamental question in neuroscience is how distributed networks of neurons communicate and coordinate dynamically and specifically. Several models propose that oscillating local networks can transiently couple to each other through phaselocked firing. Coherent local field potentials (LFP) between synaptically connected regions is often presented as evidence for such coupling. The physiological correlates of LFP signals depend on many anatomical and physiological factors, however, and how the underlying neural processes collectively generate features of different spatiotemporal scales is poorly understood. High frequency oscillations in the hippocampus, including gamma rhythms (30100 Hz) that are organized by the theta oscillations (510 Hz) during active exploration and REM sleep, as well as sharp waveripples (SWRs, 140200 Hz) during immobility or slow wave sleep, have each been associated with various aspects of learning and memory. Deciphering their physiology and functional consequences is crucial to understanding the operation of the hippocampal network. We investigated the origins and coordination of high frequency LFPs in the hippocampoentorhinal network using both biophysical models and analyses of largescale recordings in behaving and sleeping rats. We found that the synchronization of pyramidal cell spikes substantially shapes, or even dominates, the electrical signature of SWRs in area CA1 of the hippocampus. The precise mechanisms coordinating this synchrony are still unresolved, but they appear to also affect CA1 activity during theta oscillations. The input to CA1, which often arrives in the form of gammafrequency waves of activity from area CA3 and layer 3 of entorhinal cortex (EC3), did not strongly influence the timing of CA1 pyramidal cells. Rather, our data are more consistent with local network interactions governing pyramidal cells' spike timing during the integration of their inputs. Furthermore, the relative timing of input from EC3 and CA3 during the theta cycle matched that found in previous work to engage mechanisms for synapse modification and active dendritic processes. Our work demonstrates how local networks interact with upstream inputs to generate a coordinated hippocampal output during behavior and sleep, in the form of thetagamma coupling and SWRs
Experimental and analytical studies of merging plasma loops on the Caltech solar loop experiment by Rory James Perkins (
Book
)
2
editions published
in
2011
in
English
and held by
2
libraries
worldwide
more
fewer
Related Identities

Preskill, John P. Thesis advisor

Wise, Mark B. 1953 Thesis advisor

Sargent, W. L. W. (Wallace Leslie William) Thesis advisor

Walker, R. L. (Robert Lee) 19192005 Thesis advisor

Thorne, Kip S. Thesis advisor

Schwarz, John H. Thesis advisor

Ramakrishnan, Dinakar Thesis advisor

Kimble, H. Jeff Thesis advisor

Wilson, R. M. (Richard Michael) 1945 Thesis advisor

Ellis, Richard S. (Richard Salisbury) 1950 Thesis advisor
Associated Subjects
Action potentials (Electrophysiology) Algebraic topology Antennas (Electronics) Artificial satellitesTracking Asteroids AstrophysicsStudy and teaching Baade, Walter, BL Lacertae objects California Institute of Technology Cataclysmic variable stars Chandrasekhar, S.(Subrahmanyan), Comets DuBridge, Lee A.(Lee Alvin), Earthwatch (Organization) Field theory (Physics) Gamma ray astronomy Gauge fields (Physics) Gravitational waves Grinding machines Harvard University InterferometersDesign and construction Laser interferometers LensesDesign and construction Magnetohydrodynamic waves Molecular dynamics Monodromy groups Nanoelectromechanical systems Neural circuitry Nuclear reactions Optics Outer space Palomar Observatory Pasadena (Calif.) Plasma astrophysics Proton magnetic resonance spectroscopy RatsAnatomy Satellites ScienceStudy and teaching (Higher) Serendipity in science Shapley, Harlow, StarsAtmospheres Strömgren, Bengt, Supernovae Telescopes Topology Turbulence United States United States.Arms Control and Disarmament Agency Wave functions Yerkes Observatory

Alternative Names
California Institute of Technology. Division of Physics, Mathematics & Astronomy California Institute of Technology, Pasadena. Division of Physics, Mathematics and Astronomy California Institute of Technology. Physics, Mathematics & Astronomy California Institute of Technology. PM&A California Institute of Technology. PMA Division
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