23,078 research outputs found
Soft gamma repeaters outside the Local group
We propose that the best sites to search for SGRs outside the Local group are
galaxies with active massive star formation. Different possibilities to observe
SGR activity from these sites are discussed. In particular we searched for
giant flares from nearby galaxies ( -- 4 Mpc) M82,
M83, NGC 253, and NGC 4945 in the BATSE data. No candidates alike giant SGR
flares were found. The absence of such detections implies that the rate of
giant flares with energy release in the initial spike above
erg is less then 1/25 yr in our Galaxy. However, hyperflares similar to
the one of 27 December 2004 can be observed from larger distances.
Nevertheless, we do not see any significant excess of short GRBs from the Virgo
galaxy cluster and from galaxies Arp 299 and NGC 3256 with extremely high star
formation rate. This implies that the galactic rate of hyperflares with energy
release erg is less than yr. With this
constraint the fraction of possible extragalactic SGR hyperflares among BATSE
short GRBs should not exceed few percents. We present a list of short GRBs
coincident with galaxies mentioned above, and discuss the possibility that some
of them are SGR giant flares. We propose that the best target for observations
of extragalactic SGR flares by {\it Swift} is the Virgo cluster.Comment: 14 pages with 3 figures; accepted to MNRAS (final version
Growing Hair on the extremal black hole
We show that the nonlinear model in an asymptotically
space-time admits a novel local symmetry. The field action is assumed to be
quartic in the nonlinear model fields and minimally coupled to
gravity. The local symmetry transformation simultaneously twists the nonlinear
model fields and changes the space-time metric, and it can be used to
map an extremal black hole to infinitely many hairy black hole solutions.Comment: 11 pages, 1 figure, minor corrections include
How Politically Diverse Are the Social Sciences and Humanities? Survey Evidence from Six Fields
In Spring 2003, a large-scale survey of American academics was conducted using academic association membership lists from six fields: Anthropology, Economics, History, Philosophy (political and legal), Political Science, and Sociology. This paper focuses on one question: To which political party have the candidates you’ve voted for in the past ten years mostly belonged? The question was answered by 96.4 percent of academic respondents. The results show that the faculty is heavily skewed towards voting Democratic. The most lopsided fields surveyed are Anthropology with a D to R ratio of 30.2 to 1, and Sociology with 28.0 to 1. The least lopsided is Economics with 3.0 to 1. After Economics, the least lopsided is Political Science with 6.7 to 1. The average of the six ratios by field is about 15 to 1. Our analysis and related research suggest that for the the social sciences and humanities overall, a “one-big-pool” ratio of 7 to 1 is a safe lower-bound estimate, and 8 to 1 or 9 to 1 are reasonable point estimates. Thus, the social sciences and humanities are dominated by Democrats. There is little ideological diversity. We discuss Stephen Balch’s “property rights” proposal to help remedy the situation.academia; diversity; Democratic; Republican; voting; political parties
The Ideological Profile of Faculty in the Humanities and Social Sciences: A Reply to Zipp and Fenwick
ABSTRACT: In a recent Public Opinion Quarterly article “Is the Academy a Liberal Hegemony?,” John Zipp and Rudy Fenwick pit themselves against “right-wing activists and scholars,” citing our scholarship (Klein and Stern 2005a; Klein and Western 2005). Here we analyze Zipp and Fenwick’s characterization of our research and find it faulty in three important respects. We then turn to their “liberal v. conservative” findings and show they concord with our analysis. If one feels that it is a problem that humanities and social science faculty at four-year colleges and universities are vastly predominantly Democratic voters, mostly with what may called establishment-left or progressive views, then such concerns should not be allayed by Zipp and Fenwick’s article. This Reply was submitted to Public Opinion Quarterly on October 16, 2006, except that the submission did not include the Summary and without Appendix 1 that appear here at the end of the paper.-
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