Detection of early-universe gravitational-wave signatures and fundamental physics

Detection of a gravitational-wave signal of non-astrophysical origin would be a landmark discovery, potentially providing a significant clue to some of our most basic, big-picture scientific questions about the Universe. In this white paper, we survey the leading early-Universe mechanisms that may produce a detectable signal-including inflation, phase transitions, topological defects, as well as primordial black holes-and highlight the connections to fundamental physics. We review the complementarity with collider searches for new physics, and multimessenger probes of the large-scale structure of the Universe.

Implications for First-Order Cosmological Phase Transitions from the Third LIGO-Virgo Observing Run

We place constraints on the normalized energy density in gravitational waves from first-order strong phase transitions using data from Advanced LIGO and Virgo's first, second, and third observing runs. First, adopting a broken power law model, we place 95% confidence level upper limits simultaneously on the gravitational-wave energy density at 25 Hz from unresolved compact binary mergers, Ω_{CBC}<6.1×10^{-9}, and strong first-order phase transitions, Ω_{BPL}<4.4×10^{-9}. The inclusion of the former is necessary since we expect this astrophysical signal to be the foreground of any detected spectrum. We then consider two more complex phenomenological models, limiting at 25 Hz the gravitational-wave background due to bubble collisions to Ω_{pt}<5.0×10^{-9} and the background due to sound waves to Ω_{pt}<5.8×10^{-9} at 95% confidence level for phase transitions occurring at temperatures above 10^{8}  GeV.

[Visual quality comparison after multifocal toric intraocular lens or monofocal toric intraocular lens implantation]

Objective: To compare visual quality and satisfaction after multifocal toric intraocular lens (Acrysof IQ Restor toric, ART) and monofocal toric intraocular lens implantation in patients. Methods: It was a prospective nonrandomized Phase Ⅲ clinical trial. Patients with age-related cataract and corneal astigmatism were enrolled and accepted phacoemulsification combined with implantation of intraocular lens (IOL) in Henan Provincial Eye Hospital during March 2013 to December 2014. Fifty-six cases were divided into two groups according to which IOL they chose. ART group included 28 cases (3l eyes) aged from 41.0 to 72.0 years, with an average age of 61.5 years; toric group included 28 cases (33 eyes) aged from 42.0 to 75.0 years, with an average age of 63.5 years. Three months postoperatively, uncorrected distance visual acuity (UDVA) at 5, 70, 40 cm, corrected distance, intermediate, and near visual acuities, defocus curve, residual refractive astigmatism, rotational stability of the IOL, contrast sensitivity and patientsatisfaction were evaluated. All data were processed by statistic package deal SPSS 16.0. Postoperative visual acuity, residual astigmatism, IOL axial rotation and contrast sensitivity were compared by independent samples t test; preoperative and postoperative corneal astigmatism were compared by paired t-test; spectacle independency and halo incidence were processed by χ(2) test; visual satisfaction score was analyzed by Mann-Whitney test. Results: At 3 months postoperatively, in ART group, UDVA was (0.04±0.05), UIVA was (0.24±0.15), UNVA was (0.20±0.24). While in Toric group, UDVA was (0.06±0.04), UIVA was (0.30±0.13), UNVA was (0.47±0.21). There was no significant difference in UDVA between two groups(t=0.79, P=0.433). But in ART group, UIVA and UNVA were markedly better than those in Toric group(t=2.74, P=0.008; t=3.45, P<0.01). Depth of focus was 5.50 D (+2.00--3.50 D) in the ART group and 2.50 D (+1.00--1.50 D) in the Toric group. Average postoperative residual astigmatism was (-0.45±0.41)D in ART group and (-0.41±0.32)D in the Toric group. There was no significant difference between two groups (t=1.05, P=0.304). Average IOL rotation test was (2.95°±1.34°) in the ART group and (2.75°±1.64°) in the Toric group. There was no significant difference between two groups (t=0.67, P=0.452). Spectacle independency was achieved by 85.7% of patients in the ART group and 32.1% in the Toric group. There was no signifcant difference in distant visual satisfaction scores between the two groups(Z=0.71, P>0.05), while the intermediate and near visual satisfaction scores were significantly different(Z=2.27, P<0.05; Z=2.60, P<0.05) Conclusions: Both of the ART IOL and toric IOL can correct patients astigmatism. Implantation of ART IOL in patients with cataract and corneal astigmatism provided excellent distance, intermediate, and near visual outcomes. It provided better predictability of the refractive results, nice rotational stability, and good optical performance. At the same time, it improved the spectacle independency of cataract patients with astigmatism. (Chin J Ophthalmol, 2017, 53: 274-280).