TY - JOUR
T1 - Preheating from target space curvature and unitarity violation
T2 - Analysis in field space
AU - Ema, Yohei
AU - Jinno, Ryusuke
AU - Nakayama, Kazunori
AU - Van De Vis, Jorinde
N1 - Funding Information:
This work was partly funded by the Deutsche Forschungsgemeinschaft under Germany’s Excellence Strategy—EXC 2121 “Quantum Universe”—390833306. The work of R. J. was supported by Grants-in-Aid for JSPS Overseas Research Fellow (No. 201960698). This work was also supported by JSPS KAKENHI Grant (Nos. 18K03609 [KN] and 17H06359 [KN]). We thank Marieke Postma for useful comments.
Publisher Copyright:
© 2021 authors. Published by the American Physical Society.
PY - 2021/5/15
Y1 - 2021/5/15
N2 - We study particle production and unitarity violation caused by a curved target space right after inflation. We use the inflaton field value instead of cosmic time as the time variable, and derive a semiclassical formula for the spectrum of produced particles. We then derive a simple condition for unitarity violation during preheating, which we confirm by our semiclassical method and numerical solution. This condition depends not only on the target space curvature but also on the height of the inflaton potential at the end of inflation. This condition tells us, for instance, that unitarity is violated in running kinetic inflation and Higgs inflation, while unitarity is conserved in α-attractor inflation and Higgs-Palatini inflation.
AB - We study particle production and unitarity violation caused by a curved target space right after inflation. We use the inflaton field value instead of cosmic time as the time variable, and derive a semiclassical formula for the spectrum of produced particles. We then derive a simple condition for unitarity violation during preheating, which we confirm by our semiclassical method and numerical solution. This condition depends not only on the target space curvature but also on the height of the inflaton potential at the end of inflation. This condition tells us, for instance, that unitarity is violated in running kinetic inflation and Higgs inflation, while unitarity is conserved in α-attractor inflation and Higgs-Palatini inflation.
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U2 - 10.1103/PhysRevD.103.103536
DO - 10.1103/PhysRevD.103.103536
M3 - Article
AN - SCOPUS:85107372531
SN - 2470-0010
VL - 103
JO - Physical Review D
JF - Physical Review D
IS - 10
M1 - 103536
ER -