11,155 research outputs found
Standard Model Mass Spectrum in Inflationary Universe
We work out the Standard Model (SM) mass spectrum during inflation with
quantum corrections, and explore its observable consequences in the squeezed
limit of non-Gaussianity. Both non-Higgs and Higgs inflation models are studied
in detail. We also illustrate how some inflationary loop diagrams can be
computed neatly by Wick-rotating the inflation background to Euclidean
signature and by dimensional regularization.Comment: 62 pages, JHEP accepted versio
Loop Corrections to Standard Model Fields in Inflation
We calculate 1-loop corrections to the Schwinger-Keldysh propagators of
Standard-Model-like fields of spin-0, 1/2, and 1, with all renormalizable
interactions during inflation. We pay special attention to the late-time
divergences of loop corrections, and show that the divergences can be resummed
into finite results in the late-time limit using dynamical renormalization
group method. This is our first step toward studying both the standard model
and new physics in the primordial universe.Comment: 34 pages. Typos corrected. Discussions in Sec. 5 expanded. JHEP
published versio
Genetic incorporation of D-Lysine into diketoreductase in Escherichia coli cells
D-Lysine has been genetically introduced into diketoreductase in E. coli cells by utilization of an orthogonal Ph tRNA /Lysyl-tRNA synthetase pair. This is the first report on the genetic incoporation of D-amino acids into proteins, which may be generally applicable to a wide variety of applications
Schwinger-Keldysh Diagrammatics for Primordial Perturbations
We present a systematic introduction to the diagrammatic method for practical
calculations in inflationary cosmology, based on Schwinger-Keldysh path
integral formalism. We show in particular that the diagrammatic rules can be
derived directly from a classical Lagrangian even in the presence of derivative
couplings. Furthermore, we use quasi-single-field inflation as an example to
show how this formalism, combined with the trick of mixed propagator, can
significantly simplify the calculation of some in-in correlation functions. The
resulting bispectrum includes the lighter scalar case () that has been
previously studied, and the heavier scalar case () that has not been
explicitly computed for this model. The latter provides a concrete example of
quantum primordial standard clocks, in which the clock signals can be
observably large.Comment: 40 pages. JCAP published versio
Neutrino Signatures in Primordial Non-Gaussianities
We study the cosmological collider phenomenology of neutrinos in an effective
field theory. The mass spectrum of neutrinos and their characteristic
oscillatory signatures in the squeezed limit bispectrum are computed. Both
dS-covariant and slow-roll corrections are considered, so is the scenario of
electroweak symmetry breaking during inflation. Interestingly, we show that the
slow-roll background of the inflaton provides a chemical potential for the
neutrino production. The chemical potential greatly amplifies the oscillatory
signal and makes the signal observably large for heavy neutrinos without the
need of fine tuning.Comment: 31 pages, JHEP accepted versio
The disappearance of a narrow Mg II absorption system in quasar SDSS J165501.31+260517.4
In this letter, we present for the first time, the discovery of the
disappearance of a narrow Mg II absorption system
from the spectra of quasar SDSS J165501.31+260517.4 (). This
absorber is located at , and has a velocity offset of
with respect to the quasar. According to the velocity
offset and the line variability, this narrow Mg II
absorption system is likely intrinsic to the quasar. Since the corresponding UV
continuum emission and the absorption lines of another narrow Mg II
absorption system at are very
stable, we think that the disappearance of the absorption system is unlikely to
be caused by the change in ionization of absorption gas. Instead, it likely
arises from the motion of the absorption gas across the line of sight
Scalable one-way quantum computer using on-chip resonator qubits
We propose a scalable and robust architecture for one-way quantum computation
using coupled networks of superconducting transmission line resonators. In our
protocol, quantum information is encoded into the long-lived photon states of
the resonators, which have a much longer coherence time than the usual
superconducting qubits. Each resonator contains a charge qubit used for the
state initialization and local projective measurement of the photonic qubit.
Any pair of neighboring photonic qubits are coupled via a mediator charge
qubit, and large photonic cluster states can be created by applying
Stark-shifted Rabi pulses to these mediator qubits. The distinct advantage of
our architecture is that it combines both the excellent scalability of the
solid-state systems and the long coherence time of the photonic qubits.
Furthermore, this architecture is very robust against the parameter variations.Comment: 6 pages, 3 figure
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