Casimir force in Schwarzschild metric: Progress report

In this paper I report progress on both theoretical and experimental aspects. I describe two approaches to calculating putative effects of gravitational curvature on the Casimir force. The work I describe continues the quest to answer the question: do virtual field excitations follow geodesics

Compact Gravity Wave Detector

An incoming gravity wave being a stress wave is a surface with intrinsic curvature. When a light beam is parallel transported on this non-Euclidian surface it acquires an excess phase which accumulates with each curcuit. We calculate the separate contributions to excess phase from the wave geometry as well as the dynamic response of mirrors in a Michelson interferometer. Using these results and a combination of analogue and digital signal processing techniques we show how a compact interferometer can be made sensitive to gravity waves of amplitude density 10−23/√Hz within a frequency range 10−4Hz to 104Hz. As an example we describe a 10cm Michelson interferometer designed to measure gravity waves from sources as far as the Virgo cluster

New Experiments in Gravitational Physics

We propose experiments to examine and extend interpretations of the Einstein field equations. Experiments encompass the fields of astrophysics, quantum properties of the gravity field, gravitational effects on quantum electrodynamic phenomena and coupling of spinors to gravity. As an outcome of this work we were able to derive the temperature of the solar corona

Performance of an Inertially Coupled, 3-Mode Gravitational-Wave Antenna Prototype

A prototype three‐mode gravitational wave antenna which employs a two‐mode torsional transducer has been constructed and tested. For the torsional transducer the coupling from one stage to the next is via inertial forces, whereas in a conventional transducer the stage‐to‐stage coupling is proportional to the relative displacements via the springs. Experiments with our antenna‐torsional transducer prototype demonstrate a maximum antenna bandwidth of 260 Hz (29% of the antenna resonant frequency of 900 Hz) and a mechanical amplification factor of 40. A mathematical model for the three‐mode antenna has been developed and predictions of the system transfer functions and transient response are in close agreement with the measurements. Through the optimization of the transducer parameters we find that maximum fractional antenna bandwidths near 30% may be simultaneously achieved with mechanical amplification factors of 100 or more. Furthermore, the torsional transducer has a larger mechanical gain‐antenna bandwidth product than a linear transducer with similar masses

Wave Equation on Spherically Symmetric Lorentzian Metrics

Wave equation on a general spherically symmetric spacetime metric is constructed. Noether symmetries of the equation in terms of explicit functions of θ and ϕ are derived subject to certain differential constraints. By restricting the metric to flat Friedman case the Noether symmetries of the wave equation are presented. Invertible transformations are constructed from a specific subalgebra of these Noether symmetries to convert the wave equation with variable coefficients to the one with constant coefficients

Radio-Frequency Superconducting Parametric Transducer for Gravitational-Wave Antennae

We report on the design and testing of an ultrasensitive, electromechanical transducer for use on resonant mass gravitational wave antennae. The transducer is a superconducting, radio frequency resonant bridge circuit operating near 200 MHz. We have minimized several important sources of noise in this transducer system. The Johnson noise of the transducer circuit is reduced through using a superconducting niobium stripline circuit and low‐loss insulating materials. At a temperature of 4.2 K we have achieved unloaded electrical quality factors of 200 000. The bridge circuit is balanced by piezoelectric actuators which control the spacing between the proof mass and capacitive segments of the stripline circuit and we have achieved a residual bridge imbalance of 3×10−7. Finally, low noise cryogenically cooled field‐effect transistors are used for the first amplifier stage, enabling us to obtain an amplifier noise level which is 5400 times the quantum limit. The transducer, which has a 0.080 kg proof mass, was affixed to the end of a prototype, resonant bar, gravitational wave antenna with a mass of approximately 100 kg. The primary purpose of this small antenna was to evaluate the transducer, which is designed to be mounted on a much more massive antenna. Our theoretical analysis and measurements of the detector agree and indicate a burst noise temperature of 1.8 K using the 100 kg bar. This corresponds to a gravity wave burst sensitivity of h=1.1×10−16, in terms of relative strain amplitude. With no other improvements, if the transducer mechanically resonant frequency were tuned to and installed on a 2000 kg antenna, the antenna would reach a noise temperature of 1.3 mK, which is equivalent to a gravitational wave burst sensitivity, h≊5.7×10−19

Utilization of Synthetic Antibody for Fumonisin Determination in Feed and Food

Fumonisin contamination in food is limited around 2 – 4 ppm and in feed for different animals varies from 5 to 100 ppm. This regulation is to prevent animal and human from carcinogenic effect from fumonisins. Measurement of fumonisins frequently uses chromatography methods such as High-Performance Liquid Chromatography (HPLC) and Liquid chromatography tandem-mass spectrometry (LCMS/MS); however, the sample preparation and analysis process for these methods are costly and time consuming. Immunoassays have also been employed for detecting fumonisins in food or feed. Unfortunately, the instability of antibody to harsh condition such as high temperature and pH becomes the drawback for immunoassay method. Currently, the technology based on molecularly imprinting, which is called synthetic antibody, has been established for replacing antibody functions. Therefore, the aim of this review is to describe development of molecularly imprinted polymer (MIP) in fumonisin analysis in feed and food. Herein, the composition and production of MIP were described comprehensively. Bulk polymerization and solid phase synthesis were methods for production of MIP in micro and nano sizes. The application of MIP was reported for sample preparation as solid phase extraction measured continuously by HPLC showing the high recovery (> 60%). Then, MIP replaced antibody in direct competitive enzyme-linked immunosorbent assay (ELISA) for quantifying fumonisins in maize with high recovery (>90%) and limit detection (2 – 6 pM). Lastly, MIP was also employed in electrochemical sensor application as receptor for recognizing fumonisin in milk and maize. In conclusion, the performance of MIP has been applied successfully for fumonisin analysis comprehensively from sample preparation and quantification. The MIP would be developed for wider application for other toxins in feed or food such as veterinary drug, heavy metals, or pesticides

Weighing the Milky Way

We describe an experiment to measure the mass of the Milky Way galaxy. The experiment is based on calculated light travel times along orthogonal directions in the Schwarzschild metric of the Galactic center. We show that the difference is proportional to the Galactic mass. We apply the result to light travel times in a 10cm Michelson type interferometer located on Earth. The mass of the Galactic center is shown to contribute 10^-6 to the flat space component of the metric. An experiment is proposed to measure the effect.Comment: 10 pages, 1 figur

Screening for cervical cancer (By VIA Test) among selected garments worker in Chattogram, Bangladesh

Background: Bangladesh is a densely populated country of South East Asia with low resource setting where cervical cancer is the 2nd leading cause of female cancer. In more than 80% cases are diagnosed at advanced and inoperable stage. Regarding socio demographic context of this country VIA has been introduced as a screening method for cervical cancer which is most simple, cost effective, and acceptable test for all women. In Bangladesh among 3 million garment workers more than 80% are women. The objective of this study was to identify prevalence of VIA positive cases among garment workers. So that it can reduce the incidence of cervical cancer in Bangladesh. Methods: It was a cross–sectional observational study conducted in some selected garment factories in Chattogram city of Bangladesh from January 2021 to July 2021, where we enrolled 534 female workers for VIA test. Results: Among all the respondents 56% were 30 years or younger, 38% were aged between 31 to 40 years. Among 534 participants, 44.9% completed primary education, 37.3% were smoker and 34.5% had their children at early age. Majority (86.7%) had excessive whitish discharge. Post coital bleeding and irregular bleeding was 2.6% and 2.2% respectively. Considering awareness, 61.8% had idea about cervical cancer, only 1.1% had undergone VIA test in the past. In our study we found 2.4% of participants were VIA positive cases. Conclusions: It is important to include the garment workers, while making public health policies and implementation of cervical cancer control program