2,168 research outputs found
Quantum gates via relativistic remote control
We harness general relativistic effects to gain quantum control on a
stationary qubit in an optical cavity by controlling the non-inertial motion of
a different probe atom. Furthermore, we show that by considering relativistic
trajectories of the probe, we enhance the efficiency of the quantum control. We
explore the possible use of these relativistic techniques to build universal
quantum gates.Comment: 4 pages (+ 4 pages Appendix). 4 figures. RevTex 4.
Ground-state 12CO emission and a resolved jet at 115 GHz (rest-frame) in the radio loud quasar 3C318
An analysis of 44 GHz VLA observations of the z = 1.574 radio-loud quasar
3C318 has revealed emission from the redshifted J = 1 - 0 transition of the CO
molecule and spatially resolved the 6.3 kpc radio jet associated with the
quasar at 115 GHz rest-frame. The continuum-subtracted line emitter is
spatially offset from the quasar nucleus by 0.33" (2.82 kpc in projection).
This spatial offset has a significance of >8-sigma and, together with a
previously published -400 km/s velocity offset measured in the J = 2 - 1 CO
line relative to the systemic redshift of the quasar, rules out a circumnuclear
starburst or molecular gas ring and suggests that the quasar host galaxy is
either undergoing a major merger with a gas-rich galaxy or is otherwise a
highly disrupted system. If the merger scenario is correct then the event may
be in its early stages, acting as the trigger for both the young radio jets in
the quasar and a starburst in the merging galaxy. The total molecular gas mass
in the spatially offset line emitter as measured from the ground-state CO line
M_H2 = 3.7 (+/-0.4) x 10^10 (alpha_CO/0.8) M_solar. Assuming that the
line-emitter can be modelled as a rotating disk, an inclination-dependent upper
limit is derived for its dynamical mass M_dyn sin^2(i) < 3.2 x 10^9 M_solar,
suggesting that for M_H2 to remain less than M_dyn the inclination angle must
be i < 16 degrees. The far infrared and CO luminosities of 246 extragalactic
systems are collated from the literature for comparison. The high molecular gas
content of 3C318 is consistent with that of the general population of high
redshift quasars and sub-millimetre galaxies.Comment: 10 pages, 4 figures, 2 tables (additional table to appear online as
supplementary material), accepted for publication in MNRA
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The Climate Imperative and Innovative Behavior: Encouraging Greater Advances in the Production of Energy-Efficient Technologies and Services
This white paper examines why a larger array of innovative institutions, behaviors, technologies, and servicesis needed – specifically in the context of what we call “the climate imperative.” We explore possible mechanisms that can encourage the more robust development of innovative programs and policies within the State of California, with special attention to the activities of the California Public Utilities Commission
Cultural Resources Monitoring for the San Antonio Water Systems Sewer Line Repair Project, San Antonio, Bexar County, Texas
Raba Kistner, Inc. (RKI) was contracted by K-Friese + Associates (CLIENT), on behalf of San Antonio Water Systems (SAWS) to conduct archaeological monitoring for emergency repairs to a collapsed sewer lateral within West Houston Street in downtown San Antonio, Bexar County, Texas. The project involved the excavation of the area around the collapsed portion of the sewer lateral and the replacement of the damaged line. The project is located within the boundaries of a Catholic Cemetery and is between Milam Square (41BX991), which is a historic cemetery, and an area of the Children’s Hospital of San Antonio where the first City Cemeteries have been documented. As such, the City of San Antonio Office of Historic Preservation (COSA OHP) required the monitoring of the excavation activities.
The proposed project is located on lands controlled by the City of San Antonio and work was conducted by SAWS, both entities of the State of Texas. As such, the project falls under the Antiquities Code of Texas (ACT) (Texas Natural Resource Code, Title 9, Chapter 191). Furthermore, the project was also subject to review under Chapter 35 of the City of San Antonio’s Unified Development Code (UDC) (Article VI, Historic Preservation and Urban Design). All work was conducted in accordance with the Archeological Survey Standards for Texas as set forth by the Council of Texas Archeologists (CTA) and the THC under Texas Antiquities Committee Permit Number 9209.
A desktop review was conducted to determine if any previously conducted archaeological investigations or any cultural resources had been documented within the APE. Review of the Texas Archeological Sites Atlas (Atlas), revealed that no previous archaeological surveys have been conducted within the APE and that no previously recorded archaeological sites have been documented within the APE.
Cultural resources monitoring investigations for the project were conducted on December 21 and 22, 2019, and January 14, 2020. Antonio Padilla served as Project Manager and Principal Investigator, and all field work was conducted by Lindy Martinez and Susan Sincerbox. The undertaking involved the excavation of an approximately 34-foot-long (10 meter [m]-) north-south, 2.5–to–9-foot-wide east-west (0.5–to–2.74 m-) trench that extended from the sewer main located near the center of West Houston Street to the clean out located under the sidewalk north of West Houston Street. For archaeological purposes the Area of Potential Effects (APE) consisted of approximately 800 square feet or 0.018 acres. The depths of impacts reached a depth of 6 feet (1.8 m) below surface.
During the investigations, it was discovered that the entire APE has been heavily impacted by previous construction events and the installation of utilities. Throughout the excavations, construction gravels reaching a depth of 6 feet (1.8 m) below surface were observed within the entire APE, and several utilities were encountered. No intact soils were present within the trench. It appears that previous construction events and installation of utilities have removed all intact soils to the depth reached by the trench. Due to the absence of intact soils, no soils were screened. Additionally, no cultural materials or cultural features were observed during the monitoring of the excavations.
RKI has made a reasonable and good faith effort identifying cultural resources within the APE. No significant deposits or features were identified during cultural resource monitoring. As a result, RKI does not recommend further archaeological investigations within the APE. However, should changes be made to the APE, further work may be required. No diagnostic artifacts were collected during the course of the investigations, thus, no artifacts will be curated at the completion of the project. All field records generated during this project will be permanently curated at the Center for Archaeological Research at the University of Texas at San Antonio
Waverider, volume 2
The results of a study concerning a High-Speed Civilian Transport Aircraft are discussed. An evaluation of the viability of four configurations is presented. One design considered in the Waverider configuration. The Waverider creates lift at high speeds through the use of shock waves. This shocklift when combined with conventionally created lift provides high lift/drag values at higher speeds than conventional configurations. The Waverider cruises at Mach 5.5, has a range of 6,500 nautical miles, and seats 250 passengers. The aircraft is operable from existing airfields and does not require any special traffic control considerations when operating in controlled airspace
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