Tests Of Gravity Research Articles

Quantum theory of feedback cooling of an anelastic macromechanical oscillator

Conventional techniques for laser cooling, by coherent scattering off of internal states or through an optical cavity mode, have so far proved inefficient on mechanical oscillators heavier than a few nanograms. That is because larger oscillators vibrate at frequencies much too small compared to the scattering rates achievable by their coupling to auxiliary modes. Decoherence mechanisms typically observed in heavy low-frequency elastically suspended oscillators also differ markedly from what is assumed in conventional treatments of laser cooling. We show that for a low-frequency anelastic oscillator forming the mechanically compliant end mirror of a cavity, detuned optical readout, together with measurement-based feedback to stiffen and dampen it, can harness ponderomotively generated quantum correlations to realize efficient cooling to the motional ground state. This will pave the way for experiments that call for milligram-scale mechanical oscillators prepared in pure motional states, for example, for tests of gravity's effect on massive quantum systems.

Proses Produksi dan Pengendalian Mutu Bahan Baku Susu Pasteurisasi di CV. Cita Nasional Getasan Semarang

Milk is a good food for consumption because it contains good and perfect nutrients. Fresh cow's milk is widely consumed by the community, that's why the quality must be maintained during processing so that people can consume it safely. The purpose of this research is to explain how to process pasteurized milk and how to maintain the quality of pasteurized milk. This research was conducted at CV. National Citadel in November. The data collection technique used in this study was carried out by observation, interviews, and FGD methods. The results showed: (1) Pasteurized milk processing in CV. National Cita through several stages, namely mixing, homogenization, pasteurization, filling and packaging; (2) How to maintain the quality of pasteurized milk in CV. National Cita has 7 stages of testing: (a )organoleptic test (b) milk specific gravity test (c) pH and temperature test (d) alcohol test (e) fat content test (f) milk consistency test ( g) tatl solid and non fat solid test (h) MBRT test; (3) raw materials in the form of forage and concentrates

Search for scalar-tensor mixed polarization modes of gravitational waves

An additional scalar degree of freedom for a gravitational wave is often predicted in theories of gravity beyond general relativity and can be used for a model-agnostic test of gravity. In this letter, we report the direct search for the scalar-tensor mixed polarization modes of gravitational waves from compact binaries in a strong regime of gravity by analyzing the data of GW170814 and GW170817, which are the merger events of binary black holes and binary neutron stars, respectively. Consequently, we obtain the constraints on the ratio of scalar-mode amplitude to tensor-mode amplitude: $\lesssim 0.20$ for GW170814 and $\lesssim 0.068$ for GW170817, which are the tightest constraints on the scalar amplitude in a strong regime of gravity before merger.

Axion homeopathy: screening dilaton interactions

Cosmologically active Brans-Dicke (or dilaton) scalar fields are generically ruled out by solar system tests of gravity unless their couplings to ordinary matter are much suppressed relative to gravitational strength, and this is a major hindrance when building realistic models of light dilatons coupled to matter. We propose a new mechanism for evading such bounds if matter also couples to a light axion, that exploits nonlinear target-space curvature interactions to qualitatively change how the fields respond to a gravitating source. We find that dilaton-matter couplings that would be excluded in the absence of an axion can become acceptable given an additional small axion-matter coupling, and this is possible because the axion-dilaton interactions end up converting the would-be dilaton profile into an axion profile. The trajectories of matter test bodies are then controlled by the much weaker axion-matter couplings and can easily be small enough to escape detection. We call this mechanism Axion Homeopathy because the evasion of the dilaton-coupling bounds persists for extremely small axion couplings provided only that they are nonzero. We explore the mechanism using axio-dilaton equations that are SL(2,ℝ) invariant (as often appear in string compactifications), since for these the general solutions exterior to a spherically symmetric source can be found analytically. We use this solution to compute the relevant PPN parameters, γ PPN and β PPN, and verify that their deviation from unity can be much smaller than it would have been in the absence of axion-matter couplings and can therefore evade the experimental bounds.

EVALUATION OF THE PHYSICO-MECHANICAL PROPERTIES OF PLYWOOD PANELS AND LAMINATED VENEER LUMBER OF Pinus glabra Walt.

This work evaluated the potential of the species Pinus glabra for the production of laminated panels, as well as the effect of the density of the veneers and their combination on the quality of the product. The plywood and laminated veneer lumber were produced from two veneer density classes and the combination between them, namely: panels with veneers from 0.33 to 0.40 g/cm3; panels with veneers ranging from 0.41 to 0.48 g/cm3; and panels with veneers of 0.33-0.40 g/cm3 in the inner layer and 0.41-0.48 g/cm3 in the outer layer, resulting in 6 treatments. Phenol-formaldehyde was used as adhesive, whose formulation was 100 pbw of adhesive, 20 pbw of extender, 10 pbw of filler and 20 pbw of water, and applied at a grammage of 180 g/m². The pressing parameters were 1 MPa and temperature of 160ºC for 8 minutes. The evaluation of the quality of the panels was performed through tests of apparent specific gravity, static bending and glue line shear strength, according to European standards. The results presented that the production of panels, from the classification of veneers by densities and combination between them, provides gains in strength and stiffness. The parallel direction of the veneers (in LVL) provided gains in strength and stiffness when compared to panels produced with veneers perpendicular to each other (plywood), being, therefore, the most suitable for structural use. Finally, we have the conclusion that the species Pinus glabra has potential for producing laminated panels.

Experimental test on styrofoam waste addition as a partial substitute for fine aggregate to specific gravity, compressive strength, and modulus of concrete elasticity

This research aimed to determine the values of specific gravity, compressive strength, and modulus of concrete elasticity by replacing some fine aggregate with styrofoam. This research was done by using experimental methods in the Building Materials Laboratory, Department of Civil Engineering and Planning Education, Universitas Negeri Yogyakarta. The percentage of styrofoam addition as a partial substitute of fine aggregate was done at 0%, 15%, 30%, and 45%. Each percentage of styrofoam addition as a partial replacement of fine aggregate consisted of 3 cylindrical concrete specimens with a diameter of 150 mm and a height of 300 mm. Specific gravity testing of concrete was conducted 24 hours after concrete casting. The compressive strength and modulus of elasticity of the concrete were tested at 91 days. The results of the research showed that: (1) the specific gravity values of concrete decreased linearly with the value of 2345,83 kg/m3, 2242,45 kg/m3, 2154,88 kg/m3, and 2040,79 kg/m3, (2) the compressive strength values of concrete are 28,55 MPa, 18,52 MPa, 20,26 MPa, and 15,3 MPa, and (3) the modulus of elasticity values of concrete is 15969,61 MPa, 13395,58 MPa, 14994,2 MPa, dan 14479,03 MPa. From the test results, the optimal value at a percentage of 30% with a specific gravity value of concrete close to the lightweight concrete requirements and a compressive strength value meets the structural requirements.

Mechanical and environmental characteristics of geogrid-reinforced waste foundry sand beds

Different waste materials, such as fly-ash and bottom-ash, slag waste and construction and demolition waste have been extensively studied to replace depleting natural granular materials for fill applications. Waste foundry sand (WFS), a by-product from the aluminium metal-casting industry, is one such waste material that can be a viable fill material. In the current study, extensive large-scale model experimental tests were carried out on geogrid-reinforced WFS beds to understand their load–settlement behaviour. Basic characterisation studies on WFS included gradation, specific gravity, morphology, chemical composition and compaction testing. During large-scale model experimental testing, the geogrid reinforcement was placed at an optimum placement depth, and the maximum improvement in the load-carrying capacity of the footing resting on the reinforced WFS layer was quantified in terms of bearing capacity ratio (BCR). The BCR of reinforced WFS beds was found to be in the range of 1.3–2.0 based on the test conditions considered in the study. The reduction in the settlement of footing on reinforced WFS beds was also quantified. Additionally, the environmental impact of using WFS in reinforced foundation beds was assessed through leachate tests. The dissolved metal concentrations from leachate studies were found to be within permissible limits.

Identification of Specific Gravity and Solubility in ethanol from citronella oil

Introduction: Essential oil is also known as ethereal oil or flying oil (ethereal oil, volatile oil) produced by plants. The oil is volatile at room temperature without decomposition, has a bitter taste, smells good according to the smell of the plant that produces it, is generally soluble in organic solvents and insoluble in water. At high concentrations, essential oils can be used as local anesthetics, for example clove oil is used to treat toothaches, but can damage mucous membranes. Most essential oils also have strong antibacterial and antifungal properties.
 Methods: This research is a laboratory-based experimental study.
 Results: Based on the specific gravity test, the tested lemongrass oil has good quality because it meets the requirements of the Indonesian National Standard, namely the specific gravity must be in the range of 0.880 - 0.922. From the tests carried out twice (duplo) the results obtained were in that range with the value in the first
 Conclusion: The density of citronella oil is 0.8800 and the test sample meets the requirements of SNI. The solubility in ethanol of citronella oil is 1: 2 clear, the test sample meets the requirements of SNI.

Why Is the Mean Anomaly at Epoch Not Used in Tests of Non-Newtonian Gravity?

The mean anomaly at epoch η is one of the standard six Keplerian orbital elements in terms of which the motion of the two-body problem is parameterized. Along with the argument of pericenter ω, η experiences long-term rates of change induced, among other things, by general relativity and several modified models of gravity. Thus, in principle, it may be fruitfully adopted together with ω in several tests of post-Newtonian gravity performed with astronomical and astrophysical binary systems. This would allow us to enhance the gravitational signature we are interested in and to disentangle some competing disturbing effects acting as sources of systematic bias. Nonetheless, for some reasons unknown to the present author, η has never been used so far by astronomers in actual data reductions. This note aims to raise interest in the community about the possible practical use of such an orbital element or, at least, to induce experts in astronomical data processing to explicitly make clear if it is not possible to use η for testing gravitational models and, if this is the case, why.

Generalised scalar-tensor theories and self-tuning

We explore a family of generalised scalar-tensor theories that exhibit self-tuning to low scale anti de Sitter vacua, even in the presence of a large cosmological constant. We are able to examine the linearised fluctuations about these vacua and compute the corresponding amplitude. Thanks to a subtle interplay between a weak scalar coupling and a low scalar mass, it is possible to exhibit self-tuning and compatibility with solar system tests of gravity without resorting to non-linearities and unreliable screening mechanisms. The weakness of the scalar coupling and the correspondingly slow response to vacuum energy phase transitions may present some interesting possibilities for connecting early universe inflation to the cancellation of vacuum energy.

Yoga Dark Energy: natural relaxation and other dark implications of a supersymmetric gravity sector

We construct a class of 4D 'yoga' (naturally relaxed) models for which the gravitational response of heavy-particle vacuum energies is strongly suppressed. The models contain three ingredients: (i) a relaxation mechanism driven by a scalar field (the 'relaxon'), (ii) a very supersymmetric gravity sector coupled to the Standard Model in which supersymmetry is non-linearly realised, and (iii) an accidental approximate scale invariance expressed through the presence of a low-energy dilaton supermultiplet. All three are common in higher-dimensional and string constructions and although none suffices on its own, taken together they can dramatically suppress the net vacuum-energy density. The dilaton's vev τ determines the weak scale M W ∼ M p/√τ. We compute the potential for τ and find it can be stabilized in a local de Sitter minimum at sufficiently large field values to explain the size of the electroweak hierarchy, doing so using input parameters no larger than O(60) because the relevant part of the scalar potential arises as a rational function of lnτ. The de Sitter vacuum energy at the minimum is order c M 8 W α 1/τ 4, with a coefficient c ≪ \U0001d4aa(M W -4). We discuss ways to achieve c ∼ 1/M p 4 as required by observations. Scale invariance implies the dilaton couples to matter like a Brans-Dicke scalar with coupling large enough to be naively ruled out by solar-system tests of gravity. Yet because it comes paired with an axion it can evade fifth-force bounds through the novel screening mechanism described in arXiv:2110.10352. Cosmological axio-dilaton evolution predicts a natural quintessence model for Dark Energy, whose evolution might realize recent proposals to resolve the Hubble tension, and whose axion contributes to Dark Matter. We summarize inflationary implications and some remaining challenges, including the unusual supersymmetry breaking regime used and the potential for UV completions of our approach.

Solar system tests for massive conformal gravity

We find the linearized gravitational field of a static spherically symmetric mass distribution in massive conformal gravity and test it with some solar system experiments. The result is that the theory agrees with the general relativistic observations in the solar system for a determined lower bound on the graviton mass.

PENGARUH METODE MASERASI DAN SOKLETASI TERHADAP STABILITAS FISIK SEDIAAN HAIR TONIC EKSTRAK ETANOL DAUN LIDAH MERTUA (Sansevieria trifasciata P.)

Hair loss is a disorder in which the amount of hair decreases or falls out more than usual without visible thinning. Hair care requires a variety of cosmetic products such as hair conditioner, cream bath and hair tonic. Hair tonic has several advantages in optimizing efforts to prevent hair loss compared to other hair treatments. Sansevieria leaves (Sansevieria trifasciata) is a plant known as an ornamental plant. Almost all parts of the sansevieria leaves can be used, but not many know that the sansevieria leaves can be used as a hair tonic to treat hair loss. The purpose of this study was to determine the effect of maceration and soxhletation methods on the physical stability of hair tonic preparations of sansevieria leaves extract with varying concentrations of 1%, 3% and 6%. Evaluation of the preparation includes organoleptic, pH, specific gravity and viscosity tests. Physical stability tests were carried out at low temperatures (4oC) and high temperatures (40oC). The test results showed (p-value <0.05) there was no effect between maceration and soxhletation methods on the physical stability of the hair tonic preparation of sansevieria leaves extract.
 Keywords: Hair Tonic, Sansevieria Leaves, Maceration, Soxhletation, Physical Stability.

Stern-Gerlach Interferometry for Tests of Quantum Gravity and General Applications

Stern-Gerlach and/or matter-wave interferometry has garnered significant interest amongst members of the scientific community over the past few decades. Early theoretical results by Schwinger et al. demonstrate the fantastic precision capabilities required to realize a full-loop Stern-Gerlach interferometer, i.e., a Stern-Gerlach setup that houses the capability of recombining the split wave-packets in both, position and momentum space over a certain characteristic interferometric time. Over the years, several proposals have been put forward that seek to use Stern-Gerlach and/or matter-wave interferometry as a tool for a myriad of applications of general interest, some of which include tests for fundamental physics (viz., quantum wave-function collapse, stringent tests for the Einstein equivalence principle at the quantum scale, breaking the Standard Quantum Limit (SQL) barrier, and so forth), precision sensing, quantum metrology, gravitational wave detection and inertial navigation. In addition, a large volume of work in the existing literature has been dedicated to the possibility of using matter-wave interferometry for tests of quantum gravity. Inspired by the developments in this timely research field, this Perspective attempts to provide a general overview of the theory involved, the challenges that are yet to be addressed and a brief outlook on what lays ahead.

Testing modified (Horndeski) gravity by combining intrinsic galaxy alignments with cosmic shear

ABSTRACT We study the impact of modified gravity of the Horndeski class on intrinsic shape correlations in cosmic shear surveys. As these correlations intrinsic alignments are caused by tidal gravitational fields acting on galaxies as a collection of massive non-relativistic test particles, they are only sensitive to the gravitational potential, which forms in conjunction with the curvature perturbation. In contrast, the cosmic shear signal probes the sum of these two, i.e. both Bardeen potentials. Combining these probes therefore constitutes a test of gravity, derived from a single measurement. Focusing on linear scales and alignments of elliptical galaxies, we study the impact on inference of the braiding $\hat{\alpha }_{\rm B}$ and the time evolution of the Planck mass $\hat{\alpha }_{\rm M}$ by treating IAs as a genuine signal contributing to the overall ellipticity correlation. We find that for euclid, IAs can help to improve constraints on modified gravity of the Horndeski-class by 10 per cent if the alignment parameter needed for the linear alignment model is provided by simulations. If, however, the IA needs to be self-calibrated, all of the sensitivity is put into the inference of the alignment strength D since there is a very strong correlation with the evolution of the Planck mass. Thus, diminishing the benefit of IA for probing modified gravitational theories. While this paper shows results mainly for modified gravity parameters, similar deductions can be drawn for the investigation of anisotropic stresses, parametrized modifications to the Poisson equation, the phenomenology of gravitational slip and to breaking degeneracies in a standard cosmology.

Investigating the effects of specimen diameter on the relationships between mechanical and physical properties of limestone

Engineering applications, either on or within rock bodies, typically require detailed characterizations of rock physical and mechanical properties, as both properties affect the design process and construction phase and are also related to safety and sustainability of structures. Various in-situ and laboratory tests have been used to quantify rock properties. However, the tests are expensive, time consuming and require high quality test samples, especially for laboratory tests. Additionally, available core samples may not meet test standards, which require about 54 mm (NX size) core, as suggested by the American Society for Testing and Materials (ASTM) and the International Society of Rock Mechanics (ISRM). This study aims to investigate the effects of core sample diameter on the relationships between mechanical and physical properties of rock, using the example of limestone as a test material. 190 limestone core samples were prepared in five different diameters: 24.94, 38.07, 47.7, 53.99 (NX) and 63.16 mm. Uniaxial compressive strength (UCS), diametrical and axial point load index (PLID-A), indirect tensile strength (ITS), Schmidt hammer (SHV), natural unit weight (γn), specific gravity (Gs), water content (wc) and porosity (n) tests were performed on these core samples. The results indicate that sample diameter clearly affects the relationships between mechanical and physical properties of limestone rock, leading to broad measurement variations for most tests. Substantial agreement was found between this study and previous studies of NX size samples of limestone.

Post-Newtonian gravitational and scalar waves in scalar-Gauss–Bonnet gravity

Gravitational waves emitted by black hole binary inspiral and mergers enable unprecedented strong-field tests of gravity, requiring accurate theoretical modeling of the expected signals in extensions of general relativity. In this paper we model the gravitational wave emission of inspiralling binaries in scalar Gauss–Bonnet gravity theories. Going beyond the weak-coupling approximation, we derive the gravitational waveform to relative first post-Newtonian order beyond the quadrupole approximation and calculate new contributions from nonlinear curvature terms. We also compute the scalar waveform to relative 0.5PN order beyond the leading −0.5PN order terms. We quantify the effect of these terms and provide ready-to-implement gravitational wave and scalar waveforms as well as the Fourier domain phase for quasi-circular binaries. We also perform a parameter space study, which indicates that the values of black hole scalar charges play a crucial role in the detectability of deviation from general relativity. We also compare the scalar waveforms to numerical relativity simulations to assess the impact of the relativistic corrections to the scalar radiation. Our results provide important foundations for future precision tests of gravity.

Characterization of the Physical and Mechanical Properties of the Harrat Ash Shaam Basalt (HASB)/Northeast Jordan

Due to the mass demand for excellent construction materials for infrared and super structures in Jordan, intensive field and laboratory works were carried out to determine the quality of basalt as a source for construction uses or as aggregate materials. Representative basaltic samples were collected from four quarries in Harrat Ash Shaam Basalt (HASB), northeast Jordan (Al-Azraq, Tel-Hassan, Q’a-Khanna and Al-Aritayin). Necessary and accentual quality control tests were carried out on 17 samples of basalt to determine the physical and mechanical properties of target samples, whereas petrographic and chemical analysis for some representative samples have been carried out using a polarizing microscope and X-ray fluorescence (XRF). This study aims to focus on the main engineering characteristics of the basalt rocks and to shed some light on their properties. This work represents the results of petrographic and chemical analysis, tests of abrasion, absorption, specific gravity, unit weight and void ratio, sieve analysis (gradation), soundness, flakiness and elongation indices, pulse velocity and compressive strength. Petrographic studies show that the basalt is characterized by a presence mainly of calcic-plagioclase feldspar, pyroxene-augite and olivine. The composition of the basaltic samples reflects ultrabasic-basic (Basanite-Tholeiitic basalt type). The basalt is characterized by higher specific gravity, lower absorption and medium abrasion loss values, and resistance to corrosion, with medium to high compressive strength. The results of the studied physical and mechanical properties of the basalt that have been tested comply with the standard requirements. In most of the studies, basalt has good physical and mechanical properties that can be used for engineering applications.

STABILIZATION OF LIANG ANGGANG SAND WITH FLY ASH AND CEMENT AS SUBGRADE IMPROVEMENT MATERIALS

The more coal production is produced, the more waste is coming from the combustion process which leads to the environmental pollution. Waste from burning coal in the form of fly ash can be used as a mixture of subgrade stability in highway construction. The purpose of this study is to determine the characteristic value of each combination of fly ash, Liang Anggang sand and cement as a mixture of subgrade layer materials. The test objects consist of 10 combinations of fly ash, Liang Anggang sand and cement. Some tests were conducted such as Atterberg Limits, Specific Gravity, Sieve Analysis, Compaction and CBR test, respectively. From all combinations of the test objects, the best combination that suits the characteristic values of a subgrade layer mixture is a combination of minimum 6% of CBR specification and a maximum of 6% of Plasticity Index (PI). The recommended economical combination for landfill soil is a combination of test objects with a composition of 75% fly ash, 20% Liang Anggang sand and 5% cements.

Characteristics of Sand at Major Quarrying Areas around Addis Ababa

This study focused on the measurements of physical and chemical characteristics of sand samples taken from Atayie, Je‐wuha, Ziway (4 quarrying sites), Mekie (4 quarrying sites), and Soderie (2 quarrying sites) were analyzed by conducting different tests, such as silt content, moisture content, bulking, sieve size, unit weight, specific gravity, water absorption, and organic impurities tests. After conducting those tests, the results of sand samples taken from Atayie, Je‐wuha, Alagie, and Bosat Fokie sites satisfied 100% test standard requirements. In the same way, Kiera and Atie leman sand sample satisfies the 90% test requirement while Lolie basuma sand satisfies 80% test requirements and Endala chebie satisfies 70% among 10 tests with respective requirements. However, the result of sand samples taken from Langano, Godo, Melka Jelo, and Dehera Degaga satisfies below 50% of the tests among the 10 test parameters.