149 citations · 2.6k across the 63 of their papers we have counts for
64 papers
Multi-Stage and Multi-Field Inflation in Random Inflationary Landscapes
Xingang Chen, Lucas Pinol, Zhong-Zhi Xianyu +1
Generic potentials in an inflationary landscape are typically too steep to support a prolonged period of cosmic inflation. Atypical flat regions of the landscape are required to su…
Cosmological Correlators from Resurgence
Yuanzhao Li, Zhong-Zhi Xianyu
Integrating out heavy particles is generally viewed as an irreversible procedure that erases some physical information above the cutoff scale of the resulting effective theory. How…
Cosmological Collider Signals From a Triangle Loop
Zhehan Qin, Zhong-Zhi Xianyu
Triangular loop signals appear frequently in cosmological collider models but their analytical forms remain unknown due to multiple technical challenges. Here, we determine for the…
On-Shell Bootstrap of Loop Inflation Correlators with Spectral Dispersion
Haoyuan Liu, Zhehan Qin, Jiayi Wu +2
We develop a new bootstrap strategy for cosmological correlators at loop level, which we call spectral dispersion. It is based on two conceptual observations that a correlator can…
Cosmological Collider Signatures from Right-Handed Neutrino Loop
Jingtao You, Linghao Song, Chengcheng Han +3
We study cosmological collider (CC) signatures generated by right-handed neutrino loops in the setup of inflation combined with the neutrino seesaw mechanism. We formulate the infl…
Scalars at the Cosmological Collider: Full Shapes of Tree Diagrams and Bispectrum Searches using Planck Data
Soubhik Kumar, Qianshu Lu, Zhong-Zhi Xianyu +1
The Cosmological Collider (CC) provides a unique opportunity to probe the particle spectrum and fundamental interactions at extremely high energies. Massive particles, via their de…
Cosmological Collider Searches beyond the Hubble Scale with Planck Data
Soubhik Kumar, Qianshu Lu, Zhong-Zhi Xianyu +1
Searches for primordial non-Gaussianity (NG) has the potential to not only reveal the physics of cosmic inflation, but also the structure of fundamental interactions at the highest…
Massive Inflationary Amplitudes: New Representations and Degenerate Limits
Zhong-Zhi Xianyu, Jiaju Zang
The particle model building of cosmological collider physics often involves boost-breaking bilinear mixing between a heavy particle and the nearly massless inflaton mode. In cosmol…
Anatomy of Family Trees in Cosmological Correlators
Bingchu Fan, Zhong-Zhi Xianyu
The time-ordered multilayer integrals have long been cited as major challenges in the analytical study of cosmological correlators and wavefunction coefficients. The recently propo…
Primordial Stochastic Gravitational Waves from Massive Higher-Spin Bosons
Haipeng An, Zhehan Qin, Zhong-Zhi Xianyu +1
Can a stationary stone radiate gravitational waves (GWs)? While the answer is typically "no" in flat spacetime, we get a "yes" in inflationary spacetime. In this work, we study the…
Anatomy of Parity-violating Trispectra in Galaxy Surveys
Yunjia Bao, Lian-Tao Wang, Zhong-Zhi Xianyu +1
Parity-violating interactions are ubiquitous phenomena in particle physics. If they are significant during cosmic inflation, they can leave imprints on primordial perturbations and…
Fundamental Physics and Cosmology with TianQin
Jun Luo, Haipeng An, Ligong Bian +33
The exploration of the surrounding world and the universe is an important theme in the legacy of humankind. The detection of gravitational waves is adding a new dimension to this g…
Massive Inflationary Amplitudes: Differential Equations and Complete Solutions for General Trees
Haoyuan Liu, Zhong-Zhi Xianyu
We construct and solve a complete system of differential equations for general tree-level inflation correlators with an arbitrary number of massive scalar exchanges and time-depend…
MUltiplexed Survey Telescope (MUST) Science White Paper I: Overview of Large-Scale Structure Cosmology in the Era of Stage-V Spectroscopic Surveys
Cheng Zhao, Song Huang, Mengfan He +41
The MUltiplexed Survey Telescope (MUST) is a 6.5-meter telescope under development. Dedicated to highly-multiplexed, wide-field spectroscopic surveys, MUST observes over 20,000 tar…
Dispersive Bootstrap of Massive Inflation Correlators
Haoyuan Liu, Zhehan Qin, Zhong-Zhi Xianyu
Inflation correlators with massive exchanges are central observables of cosmological collider physics, and are also important theoretical data for us to better understand quantum f…
Cosmological Amplitudes in Power-Law FRW Universe
Bingchu Fan, Zhong-Zhi Xianyu
The correlators of large-scale fluctuations belong to the most important observables in modern cosmology. Recently, there have been considerable efforts in analytically understandi…
Mass Beyond Measure: Eccentric Searches for Black Hole Populations
Nicholas DePorzio, Lisa Randall, Zhong-Zhi Xianyu
Stellar mass binary black holes of unknown formation mechanism have been observed, motivating new methods for distinguishing distinct black hole populations. This work explores how…
Inflation Correlators with Multiple Massive Exchanges
Zhong-Zhi Xianyu, Jiaju Zang
The most general tree-level boundary correlation functions of quantum fields in inflationary spacetime involve multiple exchanges of massive states in the bulk, which are technical…
Nonanalyticity and On-Shell Factorization of Inflation Correlators at All Loop Orders
Zhehan Qin, Zhong-Zhi Xianyu
The dynamics of quantum fields during cosmic inflation can be probed via their late-time boundary correlators. The analytic structure of these boundary correlators contains rich ph…
Inflation Correlators at the One-Loop Order: Nonanalyticity, Factorization, Cutting Rule, and OPE
Zhehan Qin, Zhong-Zhi Xianyu
Inflation correlators with one-loop massive exchange encode rich information about the dynamics of the massive loop particles. Their nonanalytic behavior in certain soft limits lea…
Closed-Form Formulae for Inflation Correlators
Zhehan Qin, Zhong-Zhi Xianyu
We derive exact and closed-form expressions for a large class of two-point and three-point inflation correlators with the tree-level exchange of a single massive particle. The inte…
Bootstrapping One-Loop Inflation Correlators with the Spectral Decomposition
Zhong-Zhi Xianyu, Hongyu Zhang
Phenomenological studies of cosmological collider physics in recent years have identified many 1-loop inflation correlators as leading channels for discovering heavy new particles…
Helical Inflation Correlators: Partial Mellin-Barnes and Bootstrap Equations
Zhehan Qin, Zhong-Zhi Xianyu
Massive spinning particles acquire helicity-dependent chemical potentials during the inflation from axion-type couplings. Such spinning fields can mediate sizable inflaton correlat…
Phase Information in Cosmological Collider Signals
Zhehan Qin, Zhong-Zhi Xianyu
Massive particles produced during the cosmic inflation can imprint in the primordial non-Gaussianities as characteristic oscillating functions of various momentum ratios, known as…