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Nonlinear Evolution of the Bispectrum of Cosmological Perturbations
The bispectrum B(k1, k2, k3), the three-point function of density fluctuations in Fourier space, is the lowest order statistic that carries information about the spatial coherence of large-scaleExpand
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Gamma-Ray Bursts and the Earth: Exploration of Atmospheric, Biological, Climatic, and Biogeochemical Effects
Gamma-ray bursts (GRBs) are likely to have made a number of significant impacts on the Earth during the last billion years. The gamma radiation from a burst within a few kiloparsecs would quicklyExpand
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The Sponge-like Topology of Large-Scale Structure in the Universe
We describe and apply a quantitative measure of the topology of large scale structure: the genus of density contours in a smoothed density distribution. For random phase (gaussian) density fields,Expand
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Terrestrial effects of possible astrophysical sources of an AD 774-775 increase in 14C production
We examine possible sources of a substantial increase in tree ring 14C measurements for the years AD 774-775. Contrary to claims regarding a coronal mass ejection (CME), the required CME energy isExpand
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Modeling atmospheric effects of the September 1859 solar flare
[1] We have modeled atmospheric effects, especially ozone depletion, due to a solar proton event which probably accompanied the extreme magnetic storm of 1–2 September 1859. We use an inferred protonExpand
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Terrestrial Ozone Depletion Due to a Milky Way Gamma-Ray Burst
Based on cosmological rates, it is probable that at least once in the last gigayear the Earth has been irradiated by a gamma-ray burst (GRB) in our Galaxy from within 2 kpc. We have performed theExpand
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Astrophysical ionizing radiation and Earth: a brief review and census of intermittent intense sources.
Cosmic radiation backgrounds are a constraint on life, and their distribution will affect the Galactic Habitable Zone. Life on Earth has developed in the context of these backgrounds, andExpand
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DO EXTRAGALACTIC COSMIC RAYS INDUCE CYCLES IN FOSSIL DIVERSITY
Recent work has revealed a 62 ± 3 Myr cycle in fossil diversity in the past 542 Myr; however, no plausible mechanism has been found. We propose that the cycle may be caused by modulation ofExpand
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Did a Gamma-Ray Burst Initiate the Late Ordovician Mass Extinction
Gamma-ray bursts (GRBs) produce a flux of radiation detectable across the observable Universe. A GRB within our own galaxy could do considerable damage to the Earth's biosphere; rate estimatesExpand
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Causes of an ad 774–775 14C increase
Arising from F. Miyake, K. Nagaya, K. Masuda & T. Nakamura 486, 240–242 (2012)10.1038/nature11123Atmospheric 14C production is a potential window into the energy of solar proton and other cosmic rayExpand
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