Eötvös Loránd nevéhez a fizika történetében számos nagy felfedezés kötődik, igazi hírnevét, elism... more Eötvös Loránd nevéhez a fizika történetében számos nagy felfedezés kötődik, igazi hírnevét, elismertségét azonban zseniális találmánya, a róla elnevezett torziós inga hozta meg. Híres műszerének első példányát, a horizontális variométert 1890-ben építette meg, amelyet élete során folyamatosan fejlesztett tovább. Röviden áttekintjük, hogy 175 évvel Eötvös Loránd születése után és több mint 130 évvel az első torziós ingája elkészítését követően mi a jelenlegi szerepe és jelentősége az Eötvös-ingának. Magyarországon most három tudományterületen használjuk a torziós ingát. A fizikai geodéziában az ingával mérhető görbületi gradienseket a Föld elméleti alakja, a geoid finomszerkezetének meghatározására használjuk, a fizikában Eötvösék mérési pontosságát közel két nagyságrenddel felülmúlva a súlyos és a tehetetlen tömeg azonosságát igazoló ekvivalanciaelv újramérését végezzük, legújabban pedig felmerült a lehetősége bizonyos földrengések torziós ingával történő előrejelezhetőségének.
Support vector machines (SVM) with wavelet kernel has been applied to the correcting gravimetric ... more Support vector machines (SVM) with wavelet kernel has been applied to the correcting gravimetric geoid using GPS/levelling data. These data were divided into a training and a validation set in order to ensure the extendability of the approximation of the corrector surface. The optimal parameters of the SVM were considered as a trade-off between accuracy and extendability of the solution in order to avoid overlearning. Employing 194 training points and 110 validation points, SVM provided an approximation with less than 3 cm standard deviation of the error and nearly perfect extendability.
Significance of interpolation of deflection of the vertical by means of torsion balance measureme... more Significance of interpolation of deflection of the vertical by means of torsion balance measurements is pointed out, followed by outlining its fundamentals. Thereafter, its practical methods of solution will be presented.
Loránd Eötvös, with his colleagues Dezső Pekár and Jenő Fekete from 1906 carried out a series of ... more Loránd Eötvös, with his colleagues Dezső Pekár and Jenő Fekete from 1906 carried out a series of measurements (EPF measurements) validating the proportionality of the gravitational and inertial masses. In 1986, Fischbach and his colleagues revealed systematic deviations in the measurements. These deviations were slightly above the threshold of error, and were neither reproduced nor explained by later measurements, which were much more precise although they used a different method. As a result of our analysis of the EPF measurements, we found a possibility of systematic error [2] that may justify repeating the experiments under the improved conditions offered by today's state-of-the-art technical facilities. The measurements are planned to be carried out in the Jánossy Underground Research Laboratory at a depth of 30 m in the KFKI site, under appropriate undisturbed and controlled conditions. The repetition of the EPF measurements will be particularly relevant in the Eötvös Year 2019, which is planned to commemorate the 100th anniversary of the death of Loránd Eötvös. In this paper, we briefly review the background, preparations, and current status of the measurements.
Eötvös Loránd munkatársaival, Pekár Dezsővel és Fekete Jenővel 1906-tól méréssorozatot végeztek (... more Eötvös Loránd munkatársaival, Pekár Dezsővel és Fekete Jenővel 1906-tól méréssorozatot végeztek (EPF-mérések) a súlyos (gravitációs) és a tehetetlen tömeg arányosságára vonatkozóan. 1986-ban Ephraim Fischbach és társai az EPFmérési eredményekben olyan szisztematikus anyagfüggést fedeztek fel, amelyet végül kísérletileg nem tudtak igazolni, ugyanakkor az eltérések okára máig sem találtak magyarázatot. A mérések elemzésének eredményeképpen most olyan szisztematikus hibalehetőséget találtunk, amely indokolttá teszi a mai korszerű technikai lehetőségek által kínált jobb feltételek mellett a kísérletek megismétlését. 2017 júniusában a Wigner Fizikai Kutatóközpontban (Wigner FK) döntés született az EPF-mérések Eötvös-ingával történő megismétlésére és az esetleges eltérések tényleges okának feltárására. A 2017 júniusától megkezdett munkában a mérésekben és ezek előkészületeiben az MTA Wigner Fizikai Kutatóközpontja, a BME Általános-és Felsőgeodéziai Tanszéke, az Egyesület a Tudomány és Technológia Egységéért (ETTE), illetve a BME Irányítástechnika és Informatika Tanszéke vesznek részt más további szervezetek, tanszékek és szakértők bevonásával. A mérések több mint egy éves igen alapos előkészületek után a KFKI (Wigner FK) területén lévő Jánossy Földalatti Fizikai Laboratóriumban, 30 m mélységben, megfelelő nyugalmi körülmények és kontrollált feltételek között 2018 decemberében megkezdődtek. Az EPF-mérések megismétlésének külön aktualitást ad Eötvös Loránd halála 100. évfordulójának tiszteletére 2019-ben tartott Eötvös-év. Jelenlegi tanulmányunkban röviden áttekintjük a szükséges fi zikai alapismereteket, az előzményeket, beszámolunk a mérések előkészületeiről és a jelenlegi állapotáról.
In the 20th century, many torsion balance measurements had been carried out around the world. The... more In the 20th century, many torsion balance measurements had been carried out around the world. The measurements still provide a good opportunity to detect the lateral underground mass inhomogeneities and the geological fault structures using the so called edge effects in gravity gradients. Usually, the horizontal gradients were used for geophysical prospecting, but the curvature gradients measured by torsion balance remained unused. However, curvature gradients are instrumental data in geodesy, using these gradients, precise deflections of the vertical can be calculated by interpolation and the fine structure of the potential surfaces of the Earth can be derived. Based on the horizontal and the curvature gradients of gravity, the full Eötvös tensor (including the vertical gradients) can be derived by the 3D inversion method. Application of torsion balance is also important in physics. Lorand Eötvös and his colleagues Dezső Pekár and Jenő Fekete executed a series of measurements (EPF ...
Torsion-balance measurements became well known in the early 1900s, with Eötvös' famous high-p... more Torsion-balance measurements became well known in the early 1900s, with Eötvös' famous high-precision verification of the equivalence of gravitational and inertial mass. This equivalence later became the basis of general relativity. A new golden age of these measurements began in 1985, when Fischbach and his colleagues discovered regularities in the small deviations detected by Eötvös, which had previously been considered random. This led to the shortrange 5th force hypothesis, whose existence and source still have not yet been proven. Our research team started to work on the modernization of the Eötvös torsion-balance, the repetition of the EPF equivalence principle measurement and the investigation of the source of the 5th force in connection with the Eötvös Year 2019. During the experiment, particular emphasis was put on the analysis of environmental (e.g. microseismic) disturbances and the detection and filtering of the resulting, sometimes systematic, errors. These perturba...
This technique is similar to finding regression parameters of a straight line, see . This polynom... more This technique is similar to finding regression parameters of a straight line, see . This polynomial system can be solved in symbolic way via Gröbner basis and Sylvester resultant. The polynomial system can be reduced to monomials of higher order. First let us eliminate c via Gröbner basis, we get gjb 2 + acab 2 -ejab 2 ,ag + ci -bca + aea -fga + cha + efa 2 -aga 2 -bca 3 + aea 3 -
Modern computing systems, like Mathematica, are blending numeric and symbolic evaluation of many ... more Modern computing systems, like Mathematica, are blending numeric and symbolic evaluation of many algorithms improving their efficiencies (time, accuracy). In this contribution three toy-examples of the application of hybrid symbolic-numeric computations in geosciences are presented in order to illustrate the features of this advanced technique, namely: ranging GNSS satellites, computing GNSS cycle ambiguities and employing symbolic regression for verifying Kepler’s third law.
QDaedalus is an automated, computer-controlled astro-geodetic measurement system. Astronomical de... more QDaedalus is an automated, computer-controlled astro-geodetic measurement system. Astronomical deflections of the vertical measured by the QDaedalus system are significantly influenced by atmospheric refraction. Therefore, the measuring system was further improved by recording the environmental parameters influencing the refraction (air pressure, temperature, humidity) with accurate and high time resolution. In addition to meteorological parameters, refraction also depends on the spectrum of the stars. Both the continuously measured meteorological parameters and the color of the stars were taken into account in the calculation of the refraction. To control the method, we used the deflection of the vertical values of the Pistahegy point in the southern part of Budapest which were determined over 7 years during 260 night measurements. The corrected measurements fit within 0.01" with the average value of previous Pistahegy measurements. The standard deviation of the differences du...
Proceedings of International Conference on Precision Physics and Fundamental Physical Constants — PoS(FFK2019), 2019
Preparations of remeasurement of the Eötvös-Pekár-Fekete (EPF) experiment for the Weak Equivalenc... more Preparations of remeasurement of the Eötvös-Pekár-Fekete (EPF) experiment for the Weak Equivalence Principle were reported in . Here we give a brief overview of the gravity field bias and try to estimate its possible effect on the EPF experiment. We report our first test results in the solar gravity field with Cu-Au and Al-Au pairs. The estimated errors were at level 2•10⁻⁹, the same accuracy that was obtained by EPF. We also found that angular positions of the balances showed good correlation with bandpass-filtered air pressure variations hence Wiener filtering may significantly reduce this correlated noise. We did not detect any deviation from the equivalence principle considering the estimated measurement error.
Calibration of CCD sensors mounted on geodetic measuring systems
Survey Review, 2020
If the eyepiece of a total station is replaced with a CCD sensor, the most important task is to c... more If the eyepiece of a total station is replaced with a CCD sensor, the most important task is to calibrate the instrument. Calibration establishes a connection between the readings on the horizontal and vertical circles of the total station and the readings in the coordinate system of the CCD sensor. Our calibration method uses a collimator in a few meters distance, which serves as a target at infinity during the calibration. We tested the calibration using a QDaedalus astrogeodetic measuring system. The optimal number of calibration measurements, the optimal raster size, and the temperature dependence of the measurements were investigated.
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Papers by Lajos Volgyesi