Physical Sciences and Mathematics Commons^™

Perturbative Unitarity And Nec Violation In Genesis Cosmology, Yong Cai, Ji Xu, Shuai Zhao, Siyi Zhou

Physics Faculty Publications

Explorations of the violation of null energy condition (NEC) in cosmology could enrich our understanding of the very early universe and the related gravity theories. Although a fully stable NEC violation can be realized in the “beyond Horndeski” theory, it remains an open question whether a violation of the NEC is allowed by some fundamental properties of UV-complete theories or the consistency requirements of effective field theory (EFT). We investigate the tree-level perturbative unitarity for stable NEC violations in the contexts of both Galileon and “beyond Horndeski” genesis cosmology, in which the universe is asymptotically Minkowskian in the past. We …

Magnetic Structure And Radiative Captures Of Few-Nucleon Systems: Status And Prospects, Laura Elisa Marcucci, Rocco Schiavilla, Alex Gnech, Michele Viviani

Physics Faculty Publications

We review the main ingredients for an ab-initio study of few-nucleon reactions of astrophysical interest within the chiral effective field theory approach, with particular attention to radiative captures relevant for Big Bang Nucleosynthesis and stellar evolution. We conclude with an outlook for ongoing and future work.

Spectroscopic Needs For Imaging Dark Energy Experiments, Jeffrey A. Newman, Alexandra Abate, Filipe B. Abdalla, Sahar Allam, Steven W. Allen, Réza Ansari, Stephen Bailey, Wayne A. Barkhouse, Timothy C. Beers, Michael R. Blanton, Mark Brodwin, Joel R. Brownstein, Robert J. Brunner, Matias Carrasco Kind, Jorge L. Cervantes-Cota, Elliott Cheu, Nora Elisa Chisari, Matthew Colless, Johan Comparat, Jean Coupon, Carlos E. Cunha, Axel De La Macorra, Ian P. Dell'antonio, Brenda L. Frye, Eric J. Gawiser, Neil Gehrels, Kevin Grady, Alex Hagen, Patrick B. Hall, Andrew P. Hearin, Hendrik Hildebrandt, Christopher M. Hirata, Shirley Ho, Klaus Honscheid, Dragan Huterer, Željko Ivezić, Jean-Paul Kneib, Jeffrey W. Kruk, Ofer Lahav, Rachel Mandelbaum, Jennifer L. Marshall, Daniel J. Matthews, Brice Ménard, Ramon Miquel, Marc Moniez, H. W. Moos, John Moustakas, Adam D. Myers, Casey Popovich, John A. Peacock, Changbom Park, Mubdi Rahman, Jason Rhodes, Jean-Stephane Ricol, Iftach Sadeh, Anže Slozar, Samuel J. Schmidt, Daniel K. Stern, J. Anthony Tyson, Anja Von Der Linden, Risa H. Wechsler, W. M. Wood-Vasey, Andrew R. Zentner

Physics Faculty Publications

Ongoing and near-future imaging-based dark energy experiments are critically dependent upon photometric redshifts (a.k.a. photo-z’s): i.e., estimates of the redshifts of objects based only on flux information obtained through broad filters. Higher-quality, lower-scatter photo-z’s will result in smaller random errors on cosmological parameters; while systematic errors in photometric redshift estimates, if not constrained, may dominate all other uncertainties from these experiments. The desired optimization and calibration is dependent upon spectroscopic measurements for secure redshift information; this is the key application of galaxy spectroscopy for imaging-based dark energy experiments.

Hence, to achieve their full potential, imaging-based experiments …