Metallic characteristics in superlattices composed of insulators, NdMnO3/SrMnO3/LaMnO3

We report on the electronic properties of superlattices composed of three different antiferromagnetic insulators, NdMnO3/SrMnO3/LaMnO3 grown on SrTiO3 substrates. Photoemission spectra obtained by tuning the x-ray energy at the Mn 2p -> 3d edge show a Fermi cut-off, indicating metallic behavior mainly originating from Mn e_g electrons. Furthermore, the density of states near the Fermi energy and the magnetization obey a similar temperature dependence, suggesting a correlation between the spin and charge degrees of freedom at the interfaces of these oxides

Quantum mechanics emerges from information theory applied to causal horizons

It is suggested that quantum mechanics is not fundamental but emerges from classical information theory applied to causal horizons. The path integral quantization and quantum randomness can be derived by considering information loss of fields or particles crossing Rindler horizons for accelerating observers. This implies that information is one of the fundamental roots of all physical phenomena. The connection between this theory and Verlinde's entropic gravity theory is also investigated.Comment: REvtex4-1, 6pages, 2 figures, final versio

Gravity from Quantum Information

It is suggested that the Einstein equation can be derived from Landauer's principle applied to an information erasing process at a local Rindler horizon and Jacobson's idea linking the Einstein equation with thermodynamics. When matter crosses the horizon, the information of the matter disappears and the horizon entanglement entropy increases to compensate the entropy reduction. The Einstein equation describes an information-energy relation during this process, which implies that entropic gravity is related to the quantum entanglement of the vacuum and has a quantum information theoretic origin.Comment: 7 pages, revtex4-1, 2 figures, recent supporting results adde

Ginseng for erectile dysfunction

BACKGROUND: Dietary supplements with ginseng, or ginseng alone, are widely used for a broad range of conditions, including erectile dysfunction. Ginseng is particularly popular in Asian countries. Individual studies assessing its effects are mostly small, of uneven methodological quality and have unclear results. OBJECTIVES: To assess the effects of ginseng on erectile dysfunction. SEARCH METHODS: We conducted systematic searches on multiple electronic databases, including CENTRAL, MEDLINE, Embase, CINAHL, AMED, and loco-regional databases of east Asia, from their inceptions to 30 January 2021 without restrictions on language and publication status. Handsearches included conference proceedings. SELECTION CRITERIA: We included randomized or quasi-randomized controlled trials that evaluated the use of any type of ginseng as a treatment for erectile dysfunction compared to placebo or conventional treatment. DATA COLLECTION AND ANALYSIS: Two authors independently classified studies and three authors independently extracted data and assessed risk of bias in the included studies. We rated the certainty of evidence according to the GRADE approach. MAIN RESULTS: We included nine studies with 587 men with mild to moderate erectile dysfunction, aged from 20 to 70 years old. The studies all compared ginseng to placebo. We found only short-term follow-up data (up to 12 weeks).  Primary outcomes Ginseng appears to have a trivial effect on erectile dysfunction when compared to placebo based on the Erectile Function Domain of the International Index of Erectile Function (IIEF)-15 instrument (scale: 1 to 30, higher scores imply better function; mean difference [MD] 3.52, 95% confidence interval [CI] 1.79 to 5.25; I² = 0%; 3 studies; low certainty evidence) assuming a minimal clinically important difference (MCID) of 4.  Ginseng probably also has a trivial effect on erectile function when compared to placebo based on the IIEF-5 instrument (scale: 1 to 25, higher scores imply better function; MD 2.39, 95% CI 0.89 to 3.88; I² = 0%; 3 studies; moderate certainty evidence) assuming a MCID of 5. Ginseng may have little to no effect on adverse events compared to placebo (risk ratio [RR] 1.45, 95% CI 0.69 to 3.03; I² = 0%; 7 studies; low certainty evidence). Based on 86 adverse events per 1000 men in the placebo group, this would correspond to 39 more adverse events per 1000 (95% CI 27 fewer to 174 more). Secondary outcomes Ginseng may improve men's self-reported ability to have intercourse (RR 2.55, 95% CI 1.76 to 3.69; I² = 23%; 6 studies; low certainty evidence). Based on 207 per 1000 men self-reporting the ability to have intercourse in the placebo group, this would correspond to 321 more men (95% CI 158 more to 558 more) per 1000 self-reporting the ability to have intercourse. Ginseng may have a trivial effect on men's satisfaction with intercourse based on the Intercourse Satisfaction Domain of the IIEF-15 (scale: 0 to 15, higher scores imply greater satisfaction; MD 1.19, 95% CI 0.41 to 1.97; I²=0%; 3 studies; low certainty evidence) based on a MCID of 25% improvement from baseline. It may also have a trivial effect on men's satisfaction with intercourse based on item 5 of the IIEF-5 (scale: 0 to 5, higher scores imply more satisfaction; MD 0.60, 95% CI 0.02 to 1.18; 1 study; low certainty evidence) based on a MCID of 25% improvement from baseline. No study reported quality of life as an outcome. We found no trial evidence to inform comparisons to other treatments for erectile dysfunction, such as phosphodiesterase-5 inhibitors. We were unable to conduct any predefined subgroup analyses. AUTHORS' CONCLUSIONS: Based on mostly low certainty evidence, ginseng may only have trivial effects on erectile function or satisfaction with intercourse compared to placebo when assessed using validated instruments. Ginseng may improve men's self-reported ability to have intercourse. It may have little to no effect on adverse events. We found no trial evidence comparing ginseng to other agents with a more established role in treating erectile dysfunction, such as phosphodiesterase-5 inhibitors

Modifications of the Hubble Law in a Scale-Dependent Cosmology

We study some observational consequences of a recently proposed scale--dependent cosmological model for an inhomogeneous Universe. In this model the Universe is pictured as being inside a highly dense and rapidly expanding shell with the underdense center. For nearby objects ($z \ll 1$), the linear Hubble diagram is shown to remain valid even in this model, which has been demonstrated both analytically and numerically. For large $z$, we present some numerical results of the redshift--luminosity distance relation and the behavior of the mass density as a function of the redshift. It is shown that the Hubble diagram in this model for a locally $open$ Universe ($\Omega(t_0, r \sim 0)=0.1$) resembles that of the $flat$ Friedmann cosmology. This implies that study of the Hubble diagram cannot uniquely determine the value of $q_0$ or $\Omega_0$ in a model--independent way. The model also accounts for the fact that $\Omega_0$ is an increasing function of the redshift.Comment: 24 pages (REVTex File) and 2 PS figure

KMT-2016-BLG-2052L: Microlensing Binary Composed of M Dwarfs Revealed from a Very Long Time-scale Event

We present the analysis of a binary microlensing event KMT-2016-BLG-2052, for which the lensing-induced brightening of the source star lasted for 2 seasons. We determine the lens mass from the combined measurements of the microlens parallax \pie and angular Einstein radius \thetae. The measured mass indicates that the lens is a binary composed of M dwarfs with masses of $M_1\sim 0.34~M_\odot$ and $M_2\sim 0.17~M_\odot$. The measured relative lens-source proper motion of $\mu\sim 3.9~{\rm mas}~{\rm yr}^{-1}$ is smaller than $\sim 5~{\rm mas}~{\rm yr}^{-1}$ of typical Galactic lensing events, while the estimated angular Einstein radius of \thetae\sim 1.2~{\rm mas} is substantially greater than the typical value of $\sim 0.5~{\rm mas}$. Therefore, it turns out that the long time scale of the event is caused by the combination of the slow $\mu$ and large \thetae rather than the heavy mass of the lens. From the simulation of Galactic lensing events with very long time scales ($t_{\rm E}\gtrsim 100$ days), we find that the probabilities that long time-scale events are produced by lenses with masses $\geq 1.0~M_\odot$ and $\geq 3.0~M_\odot$ are $\sim 19\%$ and 2.6\%, respectively, indicating that events produced by heavy lenses comprise a minor fraction of long time-scale events. The results indicate that it is essential to determine lens masses by measuring both \pie and \thetae in order to firmly identify heavy stellar remnants such as neutron stars and black holes.Comment: 9 pages, 11 figure