Repository of works by Caltech published authors.
Type = Report or Paper
Mostrando recursos 1 - 20 de 2.300
Research on Pricing in a Gas Transportation Network - Plott, Charles R.
This report is focused upon regulatory institutions that organize prices within a network of
commodity flows. The network has economic properties of the natural gas pipeline industry and
the regulatory institutions have properties similar to those that arc being considered as alternatives
for the current rate hearing process. The questions posed at this stage of research are somewhat
basic about the technical details of the institutions and how markets perfonn when they are in place.
In order to isolate the independent effects of the institutions and separate them from many
complicating economic activities that can occur in networks, it is best to begin with a study...
Revealing topological superconductivity in extended quantum spin Hall Josephson junctions - Lee, Shu-Ping; Michaeli, Karen; Alicea, Jason; Yacoby, Amir
Quantum spin Hall-superconductor hybrids are promising sources of topological superconductivity and Majorana modes, particularly given recent progress on HgTe and InAs/GaSb. We propose a new method of revealing topological superconductivity in extended quantum spin Hall Josephson junctions supporting ‘fractional Josephson currents’. Specifically, we show that as one threads magnetic flux between the superconductors, the critical current traces an interference pattern featuring sharp fingerprints of topological superconductivity—even when noise spoils parity conservation.
Reconfigurable random bit storage using polymer-dispersed liquid crystal - Horstmeyer, Roarke; Assawaworrarit, Sid; Yang, Changhuei
We present an optical method of storing random cryptographic keys, at high densities, within an electronically reconfigurable volume of polymer-dispersed liquid crystal (PDLC) film. We demonstrate how temporary application of a voltage above PDLC's saturation threshold can completely randomize (i.e., decorrelate) its optical scattering potential in less than a second. A unique optical setup is built around this resettable PDLC film to non-electronically save many random cryptographic bits, with minimal error, over a period of one day. These random bits, stored at an unprecedented density (10 Gb/mm^3), can then be erased and transformed into a new random key space in...
Crack point stress singularities at a bi-material interface - Williams, M. L.; Zak, A. R.
The mathematical procedure for analyzing stress singularities in infinite wedges has been developed in References (1) and (2) and has been successfully applied to the analysis of stress distribution in the vicinity of a tip of a crack (3) (4). As a continuation of this study, the results presented in this note relate to the symmetrical stress field about a crack point perpendicular to a bi-material interface, and hence complement earlier results (4) wherein the crack lay along the interface.
Crack point stress singularities at a bi-material interface - Zak, A. R.; Williams, M. L.
A continuing study of plane stress singularities at
corners and cracks has been extended to the case of a crack in.
a hard (soft) material ending normal to a continuous interface
with a soft (hard) material. The increase (decrease) in stress
singularity over the homogeneous material case. which is of the
characteristic inverse square root of distance from the crack
point, is given for all relative rigidities between zero and
infinity. Associated changes in the principal stress and
distortion strain energy density distribution are also discussed,
along with indications of application to such situations as
microcrack growth near grain boundaries and earth faults in
Thermalization properties at mK temperatures of a nanoscale optomechanical resonator with acoustic-bandgap shield - Meenehan, Seán M.; Cohen, Justin D.; Gröblacher, Simon; Hill, Jeff T.; Safavi-Naeini, Amir H.; Aspelmeyer, Markus; Painter, Oskar
Optical measurements of a nanoscale silicon optomechanical crystal cavity with a mechanical resonance
frequency of 3.6 GHz are performed at sub-kelvin temperatures. We infer optical-absorption-induced
heating and damping of the mechanical resonator from measurements of phonon occupancy and motional sideband asymmetry. At the lowest probe power and lowest fridge temperature(T_f = 10 mK), the localized mechanical resonance is found to couple at a rate of γ_i/2π = 400 Hz
(Q_m = 9 x 10^6) to a thermal bath of temperature T_b ≈ 270 mK. These measurements indicate that silicon optomechanical crystals cooled to millikelvin temperatures should be suitable for a variety of experiments...
Cosmological Spectral Deconvolution - de Putter, Roland; Holder, Gilbert P.; Chang, Tzu-Ching; Doré, Olivier
One of the main goals of modern observational cosmology is to map the large scale structure of
the Universe. A potentially powerful approach for doing this would be to exploit three-dimensional
spectral maps, i.e. the specific intensity of extragalactic light as a function of wavelength and direction
on the sky, to measure spatial variations in the total extragalactic light emission and use these as a
tracer of the clustering of matter. A main challenge is that the observed intensity as a function
of wavelength is a convolution of the source luminosity density with the rest-frame spectral energy
distribution. In this paper, we introduce the method of...
Disorder-induced Floquet Topological Insulators - Titum, Paraj; Lindner, Netanel H.; Rechtsman, Mikael C.; Refael, Gil
We investigate the possibility of realizing a disorder-induced topological Floquet spectrum in two-dimensional periodically-driven systems. Such a state would be a dynamical realization of the topological Anderson insulator. We establish that a disorder-induced trivial-to-topological transition indeed occurs, and characterize it by computing the disorder averaged Bott index, suitably defined for the time-dependent system. The presence of edge states in the topological state is confirmed by exact numerical time-evolution of wavepackets on the edge of the system. We consider the optimal driving regime for experimentally observing the Floquet-Anderson topological insulator, and discuss its possible realization in photonic lattices.
Widespread rotationally-hot hydronium ion in the galactic interstellar medium - Lis, D. C.; Schilke, P.; Bergin, E. A.; Gerin, M.; Black, J. H.; Comito, C.; De Luca, M.; Godard, B.; Higgins, R.; Le Petit, F.; Pearson, J. C.; Pellegrini, E. W.; Phillips, T. G.; Yu, S.
We present new observations of the (6,6) and (9,9) inversion transitions of the hydronium ion toward Sagittarius B2(N) and W31C. Sensitive observations toward Sagittarius B2(N) show that the high, ~ 500 K, rotational temperatures characterizing the population of the highly-excited metastable H3O+ rotational levels are present over a wide range of velocities corresponding to the Sagittarius B2 envelope, as well as the foreground gas clouds between the Sun and the source. Observations of the same lines toward W31C, a line of sight that does not intersect the Central Molecular Zone, but instead traces quiescent gas in the Galactic disk, also...
An Experimental Analysis of the Structure of Legal Fees: American Rule vs. English Rule - Coughlan, Peter; Plott, Charles R.
The expanding volume of lawsuits and the ballooning of legal expenditures in recent years has attached the interest, concern, and even anger of the American public and politicians. These developments have led lawmakers to consider alternative legal fee allocation rules as methods of administering justice more efficiently. Under the traditional American rule, parties to a a lawsuit mush each pay theory own legal fees in addition to her own expenses. To evaluate the different effects of these two rules on litigant behavior and legal outcomes, we conduct a theoretical and experimental analysis of environments which can be interpreted as legal...
From Non Market Attitudes to Market Behavior: Laboratory Market Experiments in Moscow, and the Hvatat Property of Human Behavior - Menshikov, Ivan; Menshikova, Olga; Myagkov, Mikhail; Plott, Charles R.
This paper reports on laboratory market experiments that were conducted in Moscow
during the fall of 1992. Two broad concerns guided the design of the experiments. The
first concern is the obvious cultural differences between people in Russia and those in the
west where traditional laboratory market experiments have been conducted. Most
economists who have conducted experiments would assume that cultural background
would not play a major part in the equilibration process, and that the law of supply and
demand would operate essentially the same in all cultures and at all times. As Russia is
undergoing a dramatic social change and before an orientation to market attitudes
Electronic BushBroker exchange: Designing a combinatorial double auction for native vegetation offets - Nemes, Veronika; Plott, Charles R.; Stoneham, Gary
In Victoria, Australia individuals or firms wishing to proceed with development that involves the clearing of native vegetation are required to obtain an offset to replace the vegetation destroyed. This paper focuses on the design and testing of the electronic BushBroker exchange and the evaluation of alternative market institutions, while briefly
describing the metric, trading rules and contracts used in the Victorian native vegetation offset scheme. The purpose
of the design is to facilitate efficient trades of offsets between developers and landowners and to overcome the
complexities inherent in the native vegetation market. Four different types of policy and economic complexities
were identified: policy,...
Local Telephone Exchanges, Regulation, and Entry - Plott, Charles R.; Wilkie, Simon
This paper explores the relationship between technology and the policies that govern competition in the local telephone business. Analysis of competition policies requires a "long run" modeling perspective in which not only the entry and exit of firms are allowed but also allowed in changes in the nature of the investment in the underlying network technology such as network backbone and it s topology. This long run perspective requires a focus on the sources and conditions of joint production and public goods that exist in the production process and how they are influenced by the finance of the business and...
Asset Bubbles and Rationality: Additional Evidence from Capital Gains Tax Experiments - Lei, Vivian; Noussair, Charles; Plott, Charles R.
[Introduction] The remarkable phenomenon of bubbles and crashes in laboratory asset markets was first
discovered and reported in Smith et al (1988). Subsequent research inquired about the robustness
of the phenomenon and how it might be explained. One interpretation of the data is that public
knowledge of rationality is lacking in the subjects, which leads to a type of individually rational,
bubble creating speculation as part of an attempt to acquire capital gains. A different
interpretation is that subjects begin with a type of confusion or mistaken understanding about this
particular environment and that such “irrationality” at the individual level initiates the bubble,
which could be sustained...
Principles of Continuous Price Determination In An Experimental Environment With Flows Of Random Arrivals And Departures - Plott, Charles R.; Alton, Michael R.
A new experimental market environment is developed. Continuously arriving incentives replace the traditional period structure. The issue posed is whether classical principles of market behavior apply when the environment is constantly changing. Three broad results emerge. (1) Natural “flow” generalizations of the laws of demand and supply exist and dictate much of the market behavior. (2) Two different classes of laws operate: the “temporal equilibrium”, which is based on the parameters that exist in the market at a moment and the “flow competitive equilibrium,” which reflects the probabilistic structure of the parameters. (3) The markets exhibit extraordinarily high levels of...
Information Aggregation Mechanisms: Concept, Design and Implementation for a Sales Forecasting Problem - Plott, Charles R.; Chen, Kay-Yut
Information Aggregation Mechanisms are economics mechanisms designed explicitly for the purpose of collecting and aggregating information. The modern theory of rational expectations, together with the techniques and results of experimental economics, suggest that a set of properly designed markets can be a good information aggregation mechanism. The paper reports on the deployment of such an information aggregation mechanism inside Hewlett-Packard Corporation for the purpose of makings sales forecasts. Results who that IAMs performed better than traditional methods employed inside Hewlett-Packard. The structure of the mechanism, the methodology and the results are reported.
Information Aggregation in Experimental Asset Markets: Traps and Misaligned Beliefs - Plott, Charles R.; Camerer, Colin F.; Noeth, Marcus; Webber, Martin
The capacity of markets to aggregate information has been conclusively demonstrated but he limitations of that capacity have still not been fully explored. In this paper, we demonstrate the existence of "information traps". These traps appear to be a sort of equilibrium in which information existing in the market does not become revealed in prices. The foundation for the equilibrium is a pattern of misaligned beliefs in which each person's actions are based upon mistaken beliefs about the information held by others. The mistakes, themselves, have a type of mutual compatibility and cannot become revealed by the price discovery process...
The FCC Rules for the 700MHZ Auction: A Potential Disaster - Plott, Charles R.
In July 2000 the FCC issued the rules to govern the upcoming 700MHz auction. The rules are a
departure from the auction architectures previously used by the FCC. Rather than all bidding
only on individual licenses, the auction participants will be able to bid on combinations or
packages of licenses. Several combinatorial auction processes exist in the literature and testing
demonstrates that such processes have a potential for substantially increasing the efficiency of
the auction. While combinatorial auction systems have been studied in various forms, indeed a
particular auction architecture was developed and studied extensively for the FCC, the rules that
emerged from the FCC deliberations are...
Private R&D and Second Sourcing in Procurement: An Experimental Study - Plott, Charles R.; Guler, Kemal
This study focuses on two topics in government procurement problems: second sourcing, and private research and development investment procurement. A simple theoretical framework is developed to analyze the likely effects on private R&D and procurement prices of recent proposals regarding competition in procurement and the associated data0rights policy. The framework is also used to demonstrate a major flaw in the current methodology used in the evaluation of the benefits of sourcing. IN procurement environments where private R&D is an important factor and potential sellers have commercial markets which may be adversely affected, second sourcing may reduce competition in the initial...