Large Tensor-to-Scalar Ratio in Small-Field Inflation
APA
Kobayashi, T. (2014). Large Tensor-to-Scalar Ratio in Small-Field Inflation. Perimeter Institute. https://pirsa.org/14020152
MLA
Kobayashi, Takeshi. Large Tensor-to-Scalar Ratio in Small-Field Inflation. Perimeter Institute, Feb. 25, 2014, https://pirsa.org/14020152
BibTex
@misc{ pirsa_PIRSA:14020152, doi = {10.48660/14020152}, url = {https://pirsa.org/14020152}, author = {Kobayashi, Takeshi}, keywords = {Particle Physics, Cosmology}, language = {en}, title = {Large Tensor-to-Scalar Ratio in Small-Field Inflation}, publisher = {Perimeter Institute}, year = {2014}, month = {feb}, note = {PIRSA:14020152 see, \url{https://pirsa.org}} }
SISSA International School for Advanced Studies
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Talk Type
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Abstract
The production of gravitational waves from cosmic inflation > is normally bounded by the inflaton field excursion. This relation, > which is often referred to as the Lyth bound, claims that > observationally large gravitational waves are produced only if the > inflaton has a super-Planckian field range. In this talk I will point > out that this general belief is not necessarily true when there are > additional light fields producing density perturbations. Perturbations > seeded by the inflaton can be suppressed under such situations, thus > allow large gravitational waves to be produced even from small-field (i.e. > sub-Planckian) inflation. I will also show that the field bound is > taken over by the light field when the inflaton-induced perturbations > are suppressed, thus present a generalized form of the Lyth bound that > applies to the total field space. The calculations are rather simple, > so I will explain my work on a blackboard.