scholarly journals Precision measurement, scientific personalities and error budgets: the sine quibus non for big G determinations

Author(s):  
James E. Faller

Determinations of the Newtonian constant of gravitation (big G ) fit into the oftentimes-unappreciated area of physics called precision measurement—an area which includes precision measurements, null experiments and determinations of the fundamental constants. The determination of big G —a measurement which on the surface appears deceptively simple—continues to be one of Nature's greatest challenges to the skills and cunning of experimental physicists. In spite of the fact that, on the scale of the Universe, big G 's effects are so large as to single-handedly hold everything together, on the scale of an individual research laboratory, big G 's effects are so small that they go unnoticed…hidden in a background of much larger forces and noise sources. It is this ‘smallness’ that makes determining the precise value of this (seemingly unrelated to the rest of physics) fundamental constant so difficult.

2021 ◽  
pp. 2150114
Author(s):  
Manuel Urueña Palomo ◽  
Fernando Pérez Lara

The vacuum catastrophe results from the disagreement between the theoretical value of the energy density of the vacuum in quantum field theory and the estimated one observed in cosmology. In a similar attempt in which the ultraviolet catastrophe was solved, we search for the value of the cosmological constant by brute-force through computation. We explore combinations of the fundamental constants in physics performing a dimensional analysis, in search of an equation resulting in the measured energy density of the vacuum or cosmological constant that is assumed to cause the accelerated expansion of the universe.


Sensors ◽  
2021 ◽  
Vol 21 (3) ◽  
pp. 992
Author(s):  
Valeriu Savu ◽  
Mădălin Ion Rusu ◽  
Dan Savastru

The neutrinos of cosmic radiation, due to interaction with any known medium in which the Cherenkov detector is used, produce energy radiation phenomena in the form of a Cherenkov cone, in very large frequency spectrum. These neutrinos carry with them the information about the phenomena that produced them and by detecting the electromagnetic energies generated by the Cherenkov cone, we can find information about the phenomena that formed in the universe, at a much greater distance, than possibility of actually detection with current technologies. At present, a very high number of sensors for detection electromagnetic energy is required. Thus, some sensors may detect very low energy levels, which can lead to the erroneous determination of the Cherenkov cone, thus leading to information errors. As a novelty, we propose, to use these sensors for determination of the dielectrically permittivity of any known medium in which the Cherenkov detector is used, by preliminary measurements, the subsequent simulation of the data and the reconstruction of the Cherenkov cone, leading to a significant reduction of problems and minimizing the number of sensors, implicitly the cost reductions. At the same time, we offer the possibility of reconstructing the Cherenkov cone outside the detector volume.


Universe ◽  
2021 ◽  
Vol 7 (7) ◽  
pp. 222
Author(s):  
Maxim Khlopov

A.D. Sakharov’s legacy in now standard model of the Universe is not reduced to baryosynthesis but extends to the foundation of cosmoparticle physics, which studies the fundamental relationship of cosmology and particle physics. Development of cosmoparticle physics involves cross-disciplinary physical, astrophysical and cosmological studies of physics Beyond the Standard model (BSM) of elementary particles. To probe physical models for inflation, baryosynthesis and dark matter cosmoparticle physics pays special attention to model dependent messengers of the corresponding models, making their tests possible. Positive evidence for such exotic phenomena as nuclear interacting dark atoms, primordial black holes or antimatter globular cluster in our galaxy would provide the selection of viable BSM models determination of their parameters.


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