Holographic Protection of Chronology in Universes of the Godel Type (open access)

Holographic Protection of Chronology in Universes of the Godel Type

We analyze the structure of supersymmetric Godel-like cosmological solutions of string theory. Just as the original four-dimensional Godel universe, these solutions represent rotating, topologically trivial cosmologies with a homogeneous metric and closed timelike curves. First we focus on"phenomenological" aspects of holography, and identify the preferred holographic screens associated with inertial comoving observers in Godel universes. We find that holography can serve as a chronology protection agency: The closed timelike curves are either hidden behind the holographic screen, or broken by it into causal pieces. In fact, holography in Godel universes has many features in common with de Sitter space, suggesting that Godel universes could represent a supersymmetric laboratory for addressing the conceptual puzzles of de Sitter holography. Then we initiate the investigation of"microscopic" aspects of holography of Godel universes in string theory. We show that Godel universes are T-dual to pp-waves, and use this fact to generate new Godel-like solutions of string and M-theory by T-dualizing known supersymmetric pp-wave solutions.
Date: December 7, 2002
Creator: Boyda, Edward; Ganguli, Surya; Horava, Petr & Varadarajan, Uday
Object Type: Article
System: The UNT Digital Library
Agricultural Trade Issues in the 107th Congress (open access)

Agricultural Trade Issues in the 107th Congress

The 107th Congress is considering trade issues with implications for the U.S. agricultural sector. Trade in agricultural commodities and food products affects farm income and rural employment, and it also generates economic activity beyond the farm gate. With agricultural export sales the equivalent of one-quarter of farm income, some policymakers view U.S. efforts to develop market opportunities overseas as vital to the sector’s financial health. Decisions taken by the Bush Administration, and actions taken by Congress, thus will affect the outlook for agricultural trade.
Date: November 7, 2002
Creator: Hanrahan, Charles E.; Becker, Geoffrey S. & Jurenas, Remy
Object Type: Report
System: The UNT Digital Library
Agriculture and Fast Track or Trade Promotion Authority (open access)

Agriculture and Fast Track or Trade Promotion Authority

This report considers the issue of new "fast track" or trade promotion authority (APA) legislation in the 107th Congress. Moreover, the report summarizes the agricultural debates on the issue.
Date: November 7, 2002
Creator: Becker, Geoffrey S. & Hanrahan, Charles E.
Object Type: Report
System: The UNT Digital Library
Agriculture and Fast Track or Trade Promotion Authority (open access)

Agriculture and Fast Track or Trade Promotion Authority

New “fast track,” or trade promotion, authority (TPA) cleared the 107th Congress, and was signed into law (P.L. 107-210) on August 6, 2002. Such authority enables the Administration to submit negotiated foreign trade agreements to Congress for consideration under expedited procedures. Many agricultural and food industry interests were among the export-oriented enterprises that supported TPA, arguing that foreign trading partners would not seriously negotiate with an Administration that lacked it. However, some farm groups argued that fast track ultimately will lead to new agreements that have adverse effects on U.S. producers, at least of some commodities.
Date: November 7, 2002
Creator: Becker, Geoffrey S. & Hanrahan, Charles E.
Object Type: Report
System: The UNT Digital Library
Agriculture and Fast Track or Trade Promotion Authority (open access)

Agriculture and Fast Track or Trade Promotion Authority

New “fast track,” or trade promotion, authority (TPA) cleared the 107th Congress, and was signed into law (P.L. 107-210) on August 6, 2002. Such authority enables the Administration to submit negotiated foreign trade agreements to Congress for consideration under expedited procedures. Many agricultural and food industry interests were among the export-oriented enterprises that supported TPA, arguing that foreign trading partners would not seriously negotiate with an Administration that lacked it. However, some farm groups argued that fast track ultimately will lead to new agreements that have adverse effects on U.S. producers, at least of some commodities.
Date: November 7, 2002
Creator: Becker, Geoffrey S. & Hanrahan, Charles E.
Object Type: Report
System: The UNT Digital Library
An alkyne metathesis-based route toortho-dehydrobenzannulenes (open access)

An alkyne metathesis-based route toortho-dehydrobenzannulenes

An application of alkyne metathesis to 1,2-di(prop-1-ynyl)arenes, producing dehydrobenzannulenes, is described. An efficient method for selective Sonogashira couplings of bromoiodoarenes under conditions of microwave irradiation is also reported.
Date: November 7, 2002
Creator: Miljanic, Ognjen S.; Vollhardt, Peter C. & Whitener, Glenn D.
Object Type: Article
System: The UNT Digital Library
Central Asia's New States: Political Developments and Implications for U.S. Interests (open access)

Central Asia's New States: Political Developments and Implications for U.S. Interests

After the collapse of the Soviet Union in 1991, the United States recognized the independence of all the former Central Asian republics and established diplomatic relations with each by mid-March 1992. This report provides an overview of U.S. policy concerns after the Soviet collapse. The report presents the U.S. policy attention and aid to support conflict amelioration, humanitarian needs, economic development, transport (including energy pipelines) and communications, border controls, democracy, and the creation of civil societies in the South Caucasian and Central Asian states. The United States has some economic and business interests in Central Asia, particularly in oil and natural gas development in Kazakhstan, Turkmenistan, and Uzbekistan.
Date: November 7, 2002
Creator: Nichol, Jim
Object Type: Report
System: The UNT Digital Library
Extrapolation of supersymmetry-breaking parameters to high energy scales (open access)

Extrapolation of supersymmetry-breaking parameters to high energy scales

The author studies how well one can extrapolate the values of supersymmetry-breaking parameters to very high energy scales using future data from the Large Hadron Collider and an e{sup +}e{sup -} linear collider. He considers tests of the unification of squark and slepton masses in supergravity-inspired models. In gauge-mediated supersymmetry breaking models, he assess the ability to measure the mass scales associated with supersymmetry breaking. He also shows that it is possible to get good constraints on a scalar cubic stop-stop-Higgs couplings near the high scale. Different assumptions with varying levels of optimism about the accuracy of input parameter measurements are made, and their impact on the extrapolated results is documented.
Date: November 7, 2002
Creator: Martin, Stephen P
Object Type: Article
System: The UNT Digital Library
Frequency chirp and pulse shape effects in self-modulated laser wakefield accelerators (open access)

Frequency chirp and pulse shape effects in self-modulated laser wakefield accelerators

The effect of asymmetric laser pulses on plasma wave excitation in a self-modulated laser wakefield accelerator is examined. Laser pulse shape and frequency chirp asymmetries, controlled experimentally in the laser system through a grating pair compressor, are shown to strongly enhance measured electron yields for certain asymmetries. It is shown analytically that a positive (negative) frequency chirp enhances (suppresses) the growth rate of the Raman forward scattering and near-forward Raman sidescatter instabilities, but is of minimal importance for the experimental parameters. Temporal laser pulse shapes with fast rise times (< plasma period) are shown to generate larger wakes (compared to slow rise time pulses) which seed the growth of the plasma wave, resulting in enhanced electron yield.
Date: November 7, 2002
Creator: Schroeder, C. B.; Esarey, E.; Geddes, C. G. R.; Toth, Cs.; Shadwick, B. A.; van Tilborg, J. et al.
Object Type: Article
System: The UNT Digital Library
Health Insurance Coverage: Characteristics of the Insured and Uninsured Populations in 2001 (open access)

Health Insurance Coverage: Characteristics of the Insured and Uninsured Populations in 2001

The number of Americans without health insurance rose in 2001 to 41.2 million Americans - an increase of 1.4 million people from 2000. This reverses a two-year trend of falling numbers of uninsured. This report examines the characteristics of both the insured and the uninsured populations in the United States.
Date: November 7, 2002
Creator: Peterson, Chris L.
Object Type: Report
System: The UNT Digital Library
Health Insurance Coverage: Characteristics of the Insured and Uninsured Populations in 2001. November 2002 (open access)

Health Insurance Coverage: Characteristics of the Insured and Uninsured Populations in 2001. November 2002

This report examines characteristics of both the insured and the uninsured populations in the United States.
Date: November 7, 2002
Creator: Peterson, Chris L.
Object Type: Report
System: The UNT Digital Library
India-U.S. Relations (open access)

India-U.S. Relations

This report briefs the context of India - U.S relations and also discusses the bilateral issues.
Date: November 7, 2002
Creator: Kronstadt, K. Alan
Object Type: Report
System: The UNT Digital Library
Korea: U.S.-Korean Relations - Issues for Congress (open access)

Korea: U.S.-Korean Relations - Issues for Congress

None
Date: November 7, 2002
Creator: Niksch, Larry A.
Object Type: Report
System: The UNT Digital Library
Lithium: Measurement of Young's Modulus and Yield Strength (open access)

Lithium: Measurement of Young's Modulus and Yield Strength

The Lithium Collection Lens is used for anti-proton collection. In analyzing the structural behavior during operation, various material properties of lithium are often needed. properties such as density, coefficient of thermal expansion, thermal conductivity, specific heat, compressability, etc.; are well known. However, to the authors knowledge there is only one published source for Young's Modulus. This paper reviews the results from the testing of Young's Modulus and the yield strength of lithium at room temperature.
Date: November 7, 2002
Creator: Schultz, Ryan P
Object Type: Report
System: The UNT Digital Library
National and Community Service: Reauthorization of the National and Community Service Act of 1990 and the Domestic Volunteer Service Act of 1973 (open access)
Nuclear Arms Control: The U.S.-Russian Agenda (open access)

Nuclear Arms Control: The U.S.-Russian Agenda

None
Date: November 7, 2002
Creator: Woolf, Amy F.
Object Type: Report
System: The UNT Digital Library
Precise predictions for slepton pair production (open access)

Precise predictions for slepton pair production

At a future linear collider, the masses and couplings of scalar leptons can be measured with high accuracy, thus requiring precise theoretical predictions for the relevant processes. In this work, after a discussion of the expected experimental precision, the complete one-loop corrections to smuon and selectron pair production in the MSSM are presented and the effect of different contributions in the result is analyzed.
Date: November 7, 2002
Creator: Freitas, Ayres & Manteuffel, Andreas von
Object Type: Article
System: The UNT Digital Library
Slovakia: 2002 Elections (open access)

Slovakia: 2002 Elections

None
Date: November 7, 2002
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Superfund and Brownfields in the 107th Congress (open access)

Superfund and Brownfields in the 107th Congress

None
Date: November 7, 2002
Creator: Reisch, Mark
Object Type: Report
System: The UNT Digital Library
Taiwan: Recent Developments and U.S. Policy Choices (open access)

Taiwan: Recent Developments and U.S. Policy Choices

None
Date: November 7, 2002
Creator: Dumbaugh, Kerry
Object Type: Report
System: The UNT Digital Library
Thermodynamic Study of UO3(g), UO2(OH)2(g), UO2Cl2(g), and UO2F2(g) (open access)

Thermodynamic Study of UO3(g), UO2(OH)2(g), UO2Cl2(g), and UO2F2(g)

Using the transpiration method, the volatility of uranium oxide in the presence of oxygen and water vapor has been measured at temperatures ranging from 1173 to 1573 K and the volatility of uranium oxide in the presence of oxygen and chlorine has been measured at 1175 K. The major vapor species in the presence of oxygen and water vapor are found to be UO{sub 3}(g) and UO{sub 2}(0H){sub 2}(g). Third law treatment of the vaporization data yields {Delta}H{sub f}{sup o}(298) values of -790.52 {+-} 7.32 and -1199.94 {+-} 10.25 kJ/mol, respectively. The major vapor species in the presence of oxygen and chlorine is found to be UO{sub 2}Cl{sub 2}(g). Third law treatment of the vaporization data yields a {Delta}H{sub f}{sup o}(298) value of -1002.04 {+-} 3.26 kJ/mol. From an assessment of all the thermodynamic data available for UO{sub 3}(g), UO{sub 2}(OH){sub 2}(g), UO{sub 2}Cl{sub 2}(g), and UO{sub 2}F{sub 2}(g), the best {Delta}H{sub f{sup o}}(298) values for each of these species are calculated to be -796.74 {+-} 3.52, -1199.94 {+-} 10.25, -999.64 {+-} 2.40, and -1369.22 {+-} 2.87 kJ/mol, respectively. From these, the {Delta}H{sub f{sup o}} (298) values for UO{sub 2}ClOH(g), UO{sub 2}FOH(g), and UO{sub 2}FCl(g) are estimated to be -1099.79, …
Date: November 7, 2002
Creator: Ebbinghaus, B. B.; Krikorian, O. H. & Fleming, D. L.
Object Type: Report
System: The UNT Digital Library
Unemployment Benefits: Legislative Issues in the 107th Congress (open access)

Unemployment Benefits: Legislative Issues in the 107th Congress

None
Date: November 7, 2002
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Unemployment Benefits: Legislative Issues in the 107th Congress (open access)

Unemployment Benefits: Legislative Issues in the 107th Congress

None
Date: November 7, 2002
Creator: Franco, Celinda
Object Type: Report
System: The UNT Digital Library
Annual Report - Remotely Operated NDE System for Inspection of Hanford's Waste Tank Knuckle Regions and Development of a Small Roving Annulus Inspection Vehicle T-SAFT Scanning Bridge for Savannah River Site Applications (open access)

Annual Report - Remotely Operated NDE System for Inspection of Hanford's Waste Tank Knuckle Regions and Development of a Small Roving Annulus Inspection Vehicle T-SAFT Scanning Bridge for Savannah River Site Applications

The design, development, and performance testing of a prototype system known as the Remotely Operated Nondestructive Examination (RONDE)system to examine the knuckle region of a Hanford DST have been completed. The design and fabrication of a scanning bridge to support the Savannah River Site utilizing similar technology was also completed.
Date: October 7, 2002
Creator: Pardini, Allan F.; Crawford, Susan L.; Harris, Robert V.; Samuel, Todd J.; Roberts, Ron A.; Alzheimer, James M. et al.
Object Type: Report
System: The UNT Digital Library