Particles for Justice
www.particlessforjustice.org
A statement "in the strongest possible terms" against Alessandro Strumia, a well known particle theorist, whose talk on 28. Sept. 2018 at CERN argued that the primary explanation for the discrepancies between men and women in theoretical physics is that women are inherently less capable.
1810.04307
Galactic Panspermia
Ginsburg, Lingam, Loeb
Present an analytic model to estimate the total number of rocky or icy objects that could be captured by planetary systems within the MW galaxy and result in panspermia should they harbor life. Estimate the capture rate of objects ejected from planetary systems over the entire phase space as well as time. The final expression for the capture rate depends upon the velocity dispersion as well as the characteristic biological survival time and the size of the captured object. Further take into account the number of stars that an interstellar object traverses, asl well as the scale height and length of the MW's disk. The likelihood of Galactic panspermia is strongly dependent upon the survival lifetime of the putative organisms as well as the velocity of the transporter. Velocities between 10-100 km/s result in the highest probabilities. However, given large enough survival lifetimes, even hypervelocity objects traveling at over 1000 kms have a significant chance of capture, thereby increasing the likelihood of panspermia. Thus, show that panspermia is not exclusively relegated to solar-system sized scales, and the entire MW could potentially be exchanging biotic components across vast distances.
1810.04480
Gravitationally lensed quasars in Gaia: III. 22 new lensed quasars from Gaia Data Release 2
Lemon, Auger, McMahon
Report the discovery and spectroscopic confirmation of 22 new gravitationally lensed quasars found using Gaia DR2. The selection was made using several techniques: multiple Gaia detections around objects in quasars candidate catalogues, modeling of unWISE coadd pixels using Gaia astrometry, and Gaia detections offset from photometric and spectroscopic galaxies. Spectra of 33 candidates were obtained with the William Herschel Telescope, 22 of which are lensed quasars, 2 highly probably lensed quasars, 5 nearly identical quasar pairs, 1 inconclusive system, and 3 contaminants. Of the 3 confirmed quadruply imaged systems, J2145+6345 is a 2.1 arc second separation quad with 4 bright images (G=16.86, 17.26, 18.34, 18.56), making it ideal for time delay monitoring. Analyzing this new sample alongside known lenses in the Pan-STARRS footprint, and comparing to expected numbers of lenses, show that, as expected, there are bias towards systems with bright lensing galaxies and low source redshifts. Discuss possible techniques to remove this bias from future searches. A |b|>20 complete sample of lensed quasars detected by Gaia and with image separations above 1 arc second will provide a valuable statistical sample of around 350 systems. Currently only 96 known lenses satisfy these criteria, yet promisingly, the unWISE modeling technique is able to recover all of these with simple WISE-Gaia color cuts that remove ~80% of previously followed-up contaminants. Finally, provide an online database of known lenses, quasar pairs, and contaminant systems.
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