부산대학교 도서관

The expansion of the Universe is understood to have accelerated during twoepochs: in its very first moments during a period of Inflation and much morerecently, at $z < 1$, when Dark Energy is hypothesized to drive cosmicacceleration. The undiscovered mechanisms behind these two epochs representsome of the most important open problems in fundamental physics. The largecosmological volume at $2 < z < 5$, together with the ability to efficientlytarget high-$z$ galaxies with known techniques, enables large gains in thestudy of Inflation and Dark Energy. A future spectroscopic survey can test theGaussianity of the initial conditions up to a factor of ~50 better than ourcurrent bounds, crossing the crucial theoretical threshold of$\sigma(f_{NL}^{\rm local})$ of order unity that separates single field andmulti-field models. Simultaneously, it can measure the fraction of Dark Energyat the percent level up to $z = 5$, thus serving as an unprecedented test ofthe standard model and opening up a tremendous discovery space.