Читать книгу Origin and Evolution of the Universe - Группа авторов - Страница 17

The discovery that the expansion of the Universe is accelerating (see Alex Filippenko's Chapter 4 discussion of Type Ia supernovae distances) has led to the introduction of “dark energy” to the standard cosmological model. This could be a cosmological constant as introduced by Einstein, but it could also be a vacuum energy density, like the large vacuum energy during inflation. All the data collected to date are consistent with a constant vacuum energy density, but since the large vacuum energy during inflation went away, showing that dark energy changes are possible, many scientists are trying to measure the changes in the dark energy density. Studying the dark energy density as a function of time will be a primary science goal of the ESA Euclid mission and the NASA Wide Field Infrared Survey Telescope (WFIRST) mission.