Publications associées à Vie extraterrestre

Technosignatures Longevity and Lindy's Law

The probability of detecting technosignatures (i.e., evidence of technological activity beyond Earth) increases with their longevity, or the time interval over which they manifest. Therefore, the assumed distribution of longevities has some bearing on the ...

Iop Publishing Ltd2024

Upper bounds on technoemission rates from 60 years of "silence"

Claudio Grimaldi

The lack of detection to date of electromagnetic technosignatures implies either that we have been unable to detect them due to incomplete sampling of the search space or that we cannot detect them because the Earth has been located during the entire histo ...

PERGAMON-ELSEVIER SCIENCE LTD2023

Inferring the Rate of Technosignatures from 60 yr of Nondetection

Claudio Grimaldi

For about the last 60 yr the search for extraterrestrial intelligence has been monitoring the sky for evidence of remotely detectable technological life beyond Earth, with no positive results to date. While the lack of detection can be attributed to the hi ...

IOP Publishing Ltd2023

Active lithoautotrophic and methane-oxidizing microbial community in an anoxic, sub-zero, and hypersaline High Arctic spring

Ianina Altshuler

Lost Hammer Spring, located in the High Arctic of Nunavut, Canada, is one of the coldest and saltiest terrestrial springs discovered to date. It perennially discharges anoxic (

2022

Modeling non-covalent interactions in condensed phase

Veronika Juraskova

The modeling of non-covalent interactions, solvation effects, and chemical reactions in complex molecular environment is a challenging task. Current state-of-the-art approaches often rely on static computations using implicit solvent models and harmonic ap ...

EPFL2022

A birth-death-migration model for life in astrophysical environments

Claudio Grimaldi

To assess the number of life-bearing worlds in astrophysical environments, it is necessary to take the intertwined processes of abiogenesis (birth), extinction (death), and transfer of life (migration) into account. We construct a mathematical model that i ...

OXFORD UNIV PRESS2021

Copper-Catalyzed Cyanoalkylative Aziridination of N-Sulfonyl Allylamines

Qian Wang, Jieping Zhu, Minh Tu Ha, Weisi Guo

Reaction of N-arylsulfonyl allylamines with alkyl nitriles in the presence of di-tert-butyl peroxide (DTBP) and a catalytic amount of copper salt afforded homologated aziridines in 43-86% yield. A sequence involving addition of the in situ generated cyanom ...

Wiley2020

Trait-specific dispersal of bacteria in heterogeneous porous environments: from pore to porous medium scale

Tom Ian Battin, Hannes Markus Peter, David Scheidweiler, Filippo Miele

The dispersal of organisms controls the structure and dynamics of populations and communities, and can regulate ecosystem functioning. Predicting dispersal patterns across scales is important to understand microbial life in heterogeneous porous environment ...

2020

Palladium-Catalyzed Synthesis of Ketenimines from Isocyanides and Synthetic Studies Towards the Total Synthesis of Mersilongine

Mathias Mamboury

In the first chapter of this thesis, the development of two new reactions for the synthesis of vinyl ketenimines and alpha-oxo-ketenimines from isocyanides is presented. These palladium-catalyzed transformations both feature an isocyanide insertion / beta- ...

EPFL2019

Bayesian approach to SETI

Claudio Grimaldi

The search for technosignatures from hypothetical galactic civilizations is going through a new phase of intense activity. For the first time, a significant fraction of the vast search space is expected to be sampled in the foreseeable future, potentially ...

National Academy of Sciences2018

Signal coverage approach to the detection probability of hypothetical extraterrestrial emitters in the Milky Way

Claudio Grimaldi

The lack of evidence for the existence of extraterrestrial life, even the simplest forms of animal life, makes it is difficult to decide whether the search for extraterrestrial intelligence (SETI) is more a high-risk, high-payoff endeavor than a futile att ...

Nature Research2017

α-Oxo-Ketenimines from Isocyanides and α-Haloketones: Synthesis and Divergent Reactivity

Qian Wang, Jieping Zhu, Mathias Mamboury

The palladium-catalyzed reaction of a-haloketones with isocyanides afforded -oxo-ketenimines through alpha-hydride elimination of the beta-oxo-imidoyl palladium intermediates. Reaction of these relatively stable alpha-oxo ketenimines with nucleophiles suc ...

Wiley-Blackwell2017

Detecting nanoscale vibrations as signature of life

Giovanni Dietler, Sandor Kasas, Giovanni Longo, Francesco Simone Ruggeri, Petar Stupar

The existence of life in extreme conditions, in particular in extraterrestrial environments, is certainly one of the most intriguing scientific questions of our time. In this report, we demonstrate the use of an innovative nanoscale motion sensor in life-s ...

National Academy of Sciences2015

Partitioning of Si and platinum group elements between liquid and solid Fe-Si alloys

James Badro

Crystallization of the Earth's inner core fractionates major and minor elements between the solid and liquid metal, leaving physical and geochemical imprints on the Earth's core. For example, the density jump observed at the Inner Core Boundary (ICB) is re ...

Pergamon-Elsevier Science Ltd2014

NanoSIMS: Technical Aspects and Applications in Cosmochemistry and Biological Geochemistry

Anders Meibom, Shirit Cohen, Stéphanie Kéren Cohen

The NanoSIMS ion probe is a new-generation SIMS instrument, characterised by superior spatial resolution, high sensitivity and multi-collection capability. Isotope studies of certain elements can be conducted with 50-100nm resolution, making the NanoSIMS a ...

Wiley-Blackwell2013

Evidence for High-Energy Extraterrestrial Neutrinos at the IceCube Detector

Shirit Cohen, Mathieu Ribordy, Matthias Wolf

We report on results of an all-sky search for high-energy neutrino events interacting within the IceCube neutrino detector conducted between May 2010 and May 2012. The search follows up on the previous detection of two PeV neutrino events, with improved se ...

American Association for the Advancement of Science2013