27 research outputs found

    Do Rotations Beyond the Cosmological Horizon Affect the Local Inertial Frame?

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    If perturbations beyond the horizon have the velocities prescribed everywhere then the dragging of inertial frames near the origin is suppressed by an exponential factor. However if perturbations are prescribed in terms of their angular momenta there is no such suppression. We resolve this paradox and in doing so give new explicit results on the dragging of inertial frames in closed, flat and open universe with and without a cosmological constant.Comment: 12 page

    Pharmacokinetics in patients of an anti-carcinoembryonic antigen antibody radiolabeled with indium-111 using a novel diethylenetriamine pentaacetic acid chelator

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    The pharmacokinetics of the C110 anti-carcinoembryonic antigen antibody radiolabeled with 111In via a novel benzylisothiocyanate derivative of diethylenetriamine pentaacetic acid have been determined in 12 patients. The chelator was attached to the protein via a thiourea bond and in such a way that all 5 carboxymethyl arms were presumably able to participate in chelation. Patients with known or suspected colorectal carcinoma received between 5 and 20 mg of the IgG antibody labeled with 5 mCi of 111In. Individual organ radioactivity levels were quantitated, and serum and urine samples were analyzed, principally by size exclusion high-performance liquid chromatography (HPLC). Total urinary excretion averaged 0.18% of the injected dose/h with large patient to patient variation. At early times postadministration (less than 8 h) the predominant radiolabeled species in urine was free diethylenetriamine pentaacetic acid most probably administered as a small radiocontaminant in the injectate. Thereafter, radioactivity in urine was primarily present as a low molecular weight catabolic product. Analysis of serum by size exclusion HPLC occasionally showed 3 radioactivity peaks, 2 of which are due to circulating immune complexes and labeled antibody. The third peak is of low molecular weight and is due to one or more products of antibody catabolism. Transchelation of 111In to circulating transferrin was observed but at modest levels. Quantitation of organ radioactivity showed that 18 +/- 4 (SD)% of the injected dose was in the liver at 1 day postadministration and 1.4 +/- 1.1 and 1.2 +/- 0.9% was in the spleen and in both kidneys, respectively, at this time. The mean half-life for clearance of total injected radioactivity was fitted to a single exponential and was found to be 34 h (SD, 14 h; N = 13) and that for antibody alone, assessed by size exclusion HPLC analysis of serum samples, was calculated to be 22 h (SD, 8 h; N = 10). Neither of these values nor organ radioactivity levels were affected by antibody-loading dose

    Nonexistence of marginally trapped surfaces and geons in 2+1 gravity

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    We use existence results for Jang's equation and marginally outer trapped surfaces (MOTSs) in 2+1 gravity to obtain nonexistence of geons in 2+1 gravity. In particular, our results show that any 2+1 initial data set, which obeys the dominant energy condition with cosmological constant \Lambda \geq 0 and which satisfies a mild asymptotic condition, must have trivial topology. Moreover, any data set obeying these conditions cannot contain a MOTS. The asymptotic condition involves a cutoff at a finite boundary at which a null mean convexity condition is assumed to hold; this null mean convexity condition is satisfied by all the standard asymptotic boundary conditions. The results presented here strengthen various aspects of previous related results in the literature. These results not only have implications for classical 2+1 gravity but also apply to quantum 2+1 gravity when formulated using Witten's solution space quantization.Comment: v3: Elements from the original two proofs of the main result have been combined to give a single proof, thereby circumventing an issue with the second proof associated with potential blow-ups of solutions to Jang's equation. To appear in Commun. Math. Phy

    Black Holes and Instabilities of Negative Tension Branes

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    We consider the collision in 2+1 dimensions of a black hole and a negative tension brane on an orbifold. Because there is no gravitational radiation in 2+1 dimensions, the horizon area shrinks when part of the brane falls through. This provides a potential violation of the generalized second law of thermodynamics. However, tracing the details of the dynamical evolution one finds that it does not proceed from equilibrium configuration to equilibrium configuration. Instead, a catastrophic space-time singularity develops similar to the `big crunch' of Ω>1\Omega >1 FRW space-times. In the context of classical general relativity, our result demonstrates a new instability of constructions with negative tension branes.Comment: 18 pages, 3 figures, uses RevTeX. Minor typos fixed. References and one footnote adde

    Single-exterior black holes and the AdS-CFT conjecture

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    In the context of the conjectured AdS-CFT correspondence of string theory, we consider a class of asymptotically Anti-de Sitter black holes whose conformal boundary consists of a single connected component, identical to the conformal boundary of Anti-de Sitter space. In a simplified model of the boundary theory, we find that the boundary state to which the black hole corresponds is pure, but this state involves correlations that produce thermal expectation values at the usual Hawking temperature for suitably restricted classes of operators. The energy of the state is finite and agrees in the semiclassical limit with the black hole mass. We discuss the relationship between the black hole topology and the correlations in the boundary state, and speculate on generalizations of the results beyond the simplified model theory.Comment: 27 pages, LaTeX, using REVTeX v3.1 with amsfonts and epsf, with two eps figures. (v3: references updated

    Neurophysiology

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    Contains research objectives and summary of research.National Institutes of Health (Grant 1 RO1 EY01149-01)National Institutes of Health (Grant 5 P01 GM14940-07)Bell Telephone Laboratories, Inc. (Grant)National Institutes of Health (Grant 5 TO1 GM01555-07)M. I. T. Sloan Fund for Basic Researc

    Neurophysiology

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    Contains research objectives and summary of research on sixteen research projects.National Institutes of Health (Grant 5 TO1 EY00090-03)National Institutes of Health (Grant 3 RO1 EY01149-03S1)Bell Laboratories (Grant)National Institutes of Health (Grant 5 RO1 NS12307-02)National Institutes of Health (Grant K04 NS00010

    Neurophysiology

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    Contains research objectives and summary of research on ten research projects.National Institutes of Health (Grant 5 R01 EY01149-02)National Institutes of Health (Grant 1 T01 EY00090-01)Bell Telephone Laboratories, Inc. (Grant)National Institutes of Health (Grant 5 TO1 GM00778-19)National Institutes of Health (Grant 5 TO1 GM01555-08

    Geons with spin and charge

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    We construct new geon-type black holes in D>3 dimensions for Einstein's theory coupled to gauge fields. A static nondegenerate vacuum black hole has a geon quotient provided the spatial section admits a suitable discrete isometry, and an antisymmetric tensor field of rank 2 or D-2 with a pure F^2 action can be included by an appropriate (and in most cases nontrivial) choice of the field strength bundle. We find rotating geons as quotients of the Myers-Perry(-AdS) solution when D is odd and not equal to 7. For other D we show that such rotating geons, if they exist at all, cannot be continuously deformed to zero angular momentum. With a negative cosmological constant, we construct geons with angular momenta on a torus at the infinity. As an example of a nonabelian gauge field, we show that the D=4 spherically symmetric SU(2) black hole admits a geon version with a trivial gauge bundle. Various generalisations, including both black-brane geons and Yang-Mills theories with Chern-Simons terms, are briefly discussed.Comment: 26 pages, 1 figure. LaTeX with amssymb, amsmath. (v2: References and a figure added.

    Panel Discussion on Textile Recycling

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