Hvorfor bedrive kritik?

Hvorfor bedrive kritik

Vidnesbyrd og autenticitet

Spørgsmålet om, hvad der definerer det autentiske vidnesbyrd, tages op i Geoffrey Hartmans tekst om “Vidnesbyrd og autenticitet”. Her gennemgår han kritisk Jean-François Lyotards, Giorgio Agambens og Dori Laubs forskellige responser på det paradoks, som Primo Levi formulerer i De druknede og de frelste: De overlevende kan ikke aflægge fyldestgørende vidnesbyrd, dels fordi deres synsvinkel har været indsnævret, og dels fordi de, der har kunnet se mere, har kunnet dette på grund af, at de har befundet sig i det, Levi kalder “gråzonen” af udefra aftvungne, men stadig moralsk tvetydige valg, valg der senere ville kunne virke ind på deres beretninger. De sande vidner er derfor ifølge Levi de, der ikke længere kan vidne: Muselmændene, de druknede, de døde. Derudover gør Hartman, der er grundlægger og leder af Fortunoff Video Archive for Holocaust Testimonies ved Yale University, sig en række mediespecifikke overvejelser i forbindelse med bevidnelsesakten, idet han fremhæver videovidnesbyrdet som en ny kommunikativ genre med et stort potentiale, både hvad angår selve erindringshandlingen og evnen til at nå fremtidens modtagere af vidnesbyrdet

Interview with Caroline Twist

Supporting oral interview conducted for the The Norquest Family: a porción of Edinburg publication.https://scholarworks.utrgv.edu/chapsoralhistories/1031/thumbnail.jp

Orbital Orientations of Exoplanets: HAT-P-4b is Prograde and HAT-14b is Retrograde

We present observations of the Rossiter-McLaughlin effect for two exoplanetary systems, revealing the orientations of their orbits relative to the rotation axes of their parent stars. HAT-P-4b is prograde, with a sky-projected spin-orbit angle of λ = –4.9 ± 11.9 deg. In contrast, HAT-P-14b is retrograde, with λ = 189.1 ± 5.1 deg. These results conform with a previously noted pattern among the stellar hosts of close-in giant planets: hotter stars have a wide range of obliquities and cooler stars have low obliquities. This, in turn, suggests that three-body dynamics and tidal dissipation are responsible for the short-period orbits of many exoplanets. In addition, our data revealed a third body in the HAT-P-4 system, which could be a second planet or a companion star

Central Charges in Extreme Black Hole/CFT Correspondence

The Kerr/CFT correspondence has been recently broadened to the general extremal black holes under the assumption that the central charges from the non-gravitational fields vanish. To confirm this proposal, we derive the expression of the conserved charges in the Einstein-Maxwell-scalar theory with topological terms in four and five dimensions and check that the above assumption was correct. Combining the computed central charge with the expected form of the temperature, the Bekenstein-Hawking entropy of the general extremal black holes in four and five dimensions can be reproduced by using the Cardy formula.Comment: 20 pages, v2:references added, published in JHE

The NASA-UC Eta-Earth Program: III. A Super-Earth orbiting HD 97658 and a Neptune-mass planet orbiting Gl 785

We report the discovery of planets orbiting two bright, nearby early K dwarf stars, HD 97658 and Gl 785. These planets were detected by Keplerian modelling of radial velocities measured with Keck-HIRES for the NASA-UC Eta-Earth Survey. HD 97658 b is a close-in super-Earth with minimum mass Msini = 8.2 +/- 1.2 M_Earth, orbital period P = 9.494 +/- 0.005 d, and an orbit that is consistent with circular. Gl 785 b is a Neptune-mass planet with Msini = 21.6 +/- 2.0 M_Earth, P = 74.39 +/- 0.12 d, and orbital eccentricity 0.30 +/- 0.09. Photometric observations with the T12 0.8 m automatic photometric telescope at Fairborn Observatory show that HD 97658 is photometrically constant at the radial velocity period to 0.09 mmag, supporting the existence of the planet.Comment: Submitted to ApJ, 7 pages, 6 figures, 5 table

Orbital Orientations of Exoplanets: HAT-P-4b is Prograde and HAT-P-14b is Retrograde

We present observations of the Rossiter-McLaughlin effect for two exoplanetary systems, revealing the orientations of their orbits relative to the rotation axes of their parent stars. HAT-P-4b is prograde, with a sky-projected spin-orbit angle of lambda = -4.9 +/- 11.9 degrees. In contrast, HAT-P-14b is retrograde, with lambda = 189.1 +/- 5.1 degrees. These results conform with a previously noted pattern among the stellar hosts of close-in giant planets: hotter stars have a wide range of obliquities and cooler stars have low obliquities. This, in turn, suggests that three-body dynamics and tidal dissipation are responsible for the short-period orbits of many exoplanets. In addition, our data revealed a third body in the HAT-P-4 system, which could be a second planet or a companion star.Comment: AJ, in press [8 pages

Obliquities of Hot Jupiter host stars: Evidence for tidal interactions and primordial misalignments

We provide evidence that the obliquities of stars with close-in giant planets were initially nearly random, and that the low obliquities that are often observed are a consequence of star-planet tidal interactions. The evidence is based on 14 new measurements of the Rossiter-McLaughlin effect (for the systems HAT-P-6, HAT-P-7, HAT-P-16, HAT-P-24, HAT-P-32, HAT-P-34, WASP-12, WASP-16, WASP-18, WASP-19, WASP-26, WASP-31, Gl 436, and Kepler-8), as well as a critical review of previous observations. The low-obliquity (well-aligned) systems are those for which the expected tidal timescale is short, and likewise the high-obliquity (misaligned and retrograde) systems are those for which the expected timescale is long. At face value, this finding indicates that the origin of hot Jupiters involves dynamical interactions like planet-planet interactions or the Kozai effect that tilt their orbits, rather than inspiraling due to interaction with a protoplanetary disk. We discuss the status of this hypothesis and the observations that are needed for a more definitive conclusion.Comment: Accepted for publication in ApJ; typos corrected, 2 broken references fixed, 26 pages, 25 figure

The Stellar Obliquity and the Long-period planet in the HAT-P-17 Exoplanetary System

We present the measured projected obliquity – the sky-projected angle between the stellar spin axis and orbital angular momentum – of the inner planet of the HAT-P-17 multi-planet system. We measure the sky-projected obliquity of the star to be λ = 19^(+14)_( −16) degrees by modeling the Rossiter- McLaughlin (RM) effect in Keck/HIRES radial velocities (RVs). The anomalous RV time series shows an asymmetry relative to the midtransit time, ordinarily suggesting a nonzero obliquity – but in this case at least part of the asymmetry may be due to the convective blueshift, increasing the uncertainty in the determination of λ. We employ the semi-analytical approach of Hirano et al. (2011) that includes the effects of macroturbulence, instrumental broadening, and convective blueshift to accurately model the anomaly in the net RV caused by the planet eclipsing part of the rotating star. Obliquity measurements are an important tool for testing theories of planet formation and migration. To date, the measured obliquities of ∼50 Jovian planets span the full range, from prograde to retrograde, with planets orbiting cool stars preferentially showing alignment of stellar spins and planetary orbits. Our results are consistent with this pattern emerging from tidal interactions in the convective envelopes of cool stars and close-in planets. In addition, our 1.8 years of new RVs for this system show that the orbit of the outer planet is more poorly constrained than previously thought, with an orbital period now in the range of 10–36 years