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Pelted by paint, downed by debris
In: Bulletin of the atomic scientists, Band 58, Heft 5, S. 24-25
ISSN: 1938-3282
Pelted by paint, downed by debris
In: Bulletin of the Atomic Scientists, Band 58, Heft 5, S. 24-25
Opinions - Pelted by paint, downed by debris
In: The bulletin of the atomic scientists: a magazine of science and public affairs, Band 58, Heft 5, S. 24
ISSN: 0096-3402, 0096-5243, 0742-3829
Human rights in the Southern Cone
In: Bulletin of the atomic scientists, Band 37, Heft 2, S. 24-29
ISSN: 1938-3282
Human rights in the southern cone
In: The bulletin of the atomic scientists: a magazine of science and public affairs, Band 37, Heft 2, S. 24-29
ISSN: 0096-3402, 0096-5243, 0742-3829
World Affairs Online
An introduction to the issues
In: Bulletin of the atomic scientists, Band 31, Heft 7, S. 15-19
ISSN: 1938-3282
Nuclear Reactor Safety: The origins and issues of a vital debate
In: Bulletin of the atomic scientists, Band 30, Heft 8, S. 5-12
ISSN: 1938-3282
Scientists, Politics and SST: A Critical Review
In: Bulletin of the atomic scientists, Band 28, Heft 4, S. 24-30
ISSN: 1938-3282
The public and technological decisions
In: Bulletin of the atomic scientists, Band 36, Heft 6, S. 44-48
ISSN: 1938-3282
Detection of space reactors by their gamma‐ray and positron emissions
In: Science & global security: the technical basis for arms control, disarmament, and nonproliferation initiatives, Band 1, Heft 1-2, S. 129-146
ISSN: 1547-7800
Clustering and halo abundances in early dark energy cosmological models
Cold Dark Matter with cosmological constant (ΛCDM) cosmological models with early dark energy (EDE) have been proposed to resolve tensions between the Hubble constant H 0=100, h km -1pc-1 measured locally, giving h ≈ 0.73, and H0 deduced from Planck cosmic microwave background (CMB) and other early-Universe measurements plus ΛCDM, giving h ≈ 0.67. EDE models do this by adding a scalar field that temporarily adds dark energy equal to about 10 per cent of the cosmological energy density at the end of the radiation-dominated era at redshift z ∼3500. Here, we compare linear and non-linear predictions of a Planck-normalized ΛCDM model including EDE giving h = 0.728 with those of standard Planck-normalized ΛCDM with h = 0.678. We find that non-linear evolution reduces the differences between power spectra of fluctuations at low redshifts. As a result, at z = 0 the halo mass functions on galactic scales are nearly the same, with differences only 1-2 per cent. However, the differences dramatically increase at high redshifts. The EDE model predicts 50 per cent more massive clusters at z = 1 and twice more galaxy-mass haloes at z = 4. Even greater increases in abundances of galaxy-mass haloes at higher redshifts may make it easier to reionize the universe with EDE. Predicted galaxy abundances and clustering will soon be tested by the James Webb Space Telescope (JWST) observations. Positions of baryonic acoustic oscillations (BAOs) and correlation functions differ by about 2 per cent between the models-an effect that is not washed out by non-linearities. Both standard ΛCDM and the EDE model studied here agree well with presently available acoustic-scale observations, but the Dark Energy Spectroscopic Instrument and Euclid measurements will provide stringent new tests. © 2021 The Author(s). ; AK and FP thank the support of the Spanish Ministry of Science funding grant PGC2018-101931-B-I00. This work used the skun6@IAA facility managed by the Instituto de Astrofísica de Andalucía (CSIC). The equipment was funded by the Spanish Ministry of Science EU-FEDER infrastructure grantEQC2018-004366-P. MK acknowledges the support of NSF Grant No. 1519353, NASA NNX17AK38G, and the Simons Foundation. TLS acknowledges support from NASA (through grant 80NSSC18K0728) and the Research Corporation. We thank Alexie Leauthaud and Johannes Lange for a helpful discussion about weak lensing results. ; With funding from the Spanish government through the Severo Ochoa Centre of Excellence accreditation SEV-2017-0709. ; Peer reviewed
BASE
Overview
In: Science & global security: the technical basis for arms control, disarmament, and nonproliferation initiatives, Band 1, Heft 1-2, S. 59-82
ISSN: 1547-7800
The Politics of Technical Advice
In: Administrative Science Quarterly, Band 22, Heft 3, S. 526
Letters
In: Bulletin of the atomic scientists, Band 32, Heft 2, S. 2-4
ISSN: 1938-3282