Search

We present results on simultaneous observations of Class I methanol masers at 25, 36, and 44 GHz towards 22 Galactic targets carried out with the Effelsberg 100-m telescope. The study investigates relations between the hyperfine (HF) structure of the torsion–rotation transitions in CH |$_3$| OH and maser activity. By analysing the radial velocity shifts between different maser lines together with the patterns of the HF structure based on laboratory measurements and quantum-chemical calculations, we find that in any source only one specific HF transition forms the maser emission and that this transition changes from source to source. The physical conditions leading to this selective behaviour are still unclear. Using accurate laboratory rest frequencies for the 25 GHz transitions, we have refined the centre frequencies for the HF multiplets at 36, 44, and 95 GHz: |$f_{\scriptscriptstyle 36} = (36169.2488\pm 0.0002_{\scriptscriptstyle \rm stat} \pm 0.0004_{\scriptscriptstyle \rm sys})$|  MHz. |$f_{\scriptscriptstyle 44} = (44069.4176\pm 0.0002_{\scriptscriptstyle \rm stat} \pm 0.0004_{\scriptscriptstyle \rm sys})$|  MHz, and |$f_{\scriptscriptstyle 95} = (95169.4414\pm 0.0003_{\scriptscriptstyle \rm stat} \pm 0.0004_{\scriptscriptstyle \rm sys})$|  MHz. Comparison with previous observations of 44 GHz masers performed 6–10 yr ago with a Korean 21-m Korean Very Long Baseline Interferometry Network telescope towards the same targets confirms the kinematic stability of Class I maser line profiles during this time interval and reveals a systematic radial velocity shift of |$0.013\pm 0.005$|  km s |$^{-1}$| between the two telescopes. [ABSTRACT FROM AUTHOR]

Ever since the publication of Evelynn Hammonds's rejoinder to the evolving discussion of (white) queer studies (differences 1994), we have struggled to think about black female sexuality and how it matters to our understandings of prevailing tropes of feminism. The author of this essay writes across three registers: the first addresses what contemporary discoveries about black holes attempt to tell us about "matter," or what matters; the second is what Hammonds sought to disrupt or prove impossible in her essay; and the third is a meditation on the place of "elementary particles" in the physics—the possible rupture of time and space—of Hammonds's work and the work of the late Randall Kenan in his short experimental piece "Chinquapin: Elementary Particles." [ABSTRACT FROM AUTHOR]

Transhumanism sees the next step of the evolution of humanity in technology, together with the developments in the twentieth century and the influence of positivism. As a modern repetition of the golem myth, it desires to use technology as o tool for a stronger, smarter, non-sick, even immortal humanity. Transhumanists developed in an environment where the influence of humanism was reduced due to materialism and they aim to create a super human through technologies such as biotechnology, nanotechnology, artificial intelligence and cloning, and tries to bring humans to a higher position. In literature, which is a close follower mirror of social developments, transhumanist works are frequently encountered as they create a suitable environment for the development and discussion of transhumanist ideas. Therefor Transhumanism has become an important subject in world literature and has attracted the attention of French authors, especially with the twenty-first century. Michel Houellebecq, one of the leading figures of contemporary French literature, is famous for deeply processing existential themes and bringing striking subjects such as religion, nudity and the human condition into his novels by refence. His novel Elementary Particles, published in 1998, problematizes the potential return of transhumanist ideas, human desires and technological advances, while depicting a modern society where life has lost its meaning with the advancement of scientific developments. This article aims to reveal the author’s ideas for the future of humanity in a world driven by the increasing use of technology while critically investigating the traces of transhumanism in Houellebecq’s Elementary Particles. After providing an overview of the foundations of the theory by creating a framework for understanding the concept of transhumanism, the study tries to reveal the author’s transhumanist ideas and the potential consequences of transcending human boundaries by making use of important themes and passages in the novel.

From viewpoints of crystallography and of elementary particles, we explore symmetries of multivectors in the geometric algebra Cl(3, 1) that can be used to describe space-time. [ABSTRACT FROM AUTHOR]

Transhumanism sees the next step of the evolution of humanity in technology, together with the developments in the twentieth century and the influence of positivism. It desires to use technology as o tool for a stronger, smarter, non-sick, even immortal humanity. Transhumanists developed in an environment where the influence of humanism was reduced due to materialism and they aim to create a superhuman through technologies such as biotechnology, nanotechnology, artificial intelligence and cloning. In literature, which is a close follower mirror of social developments, transhumanist works are frequently encountered as they create a suitable environment for the development and discussion of transhumanist ideas. Therefor Transhumanism has become an important subject in world literature and has attracted the attention of French authors. Michel Houellebecq, one of the leading figures of contemporary French literature, is famous for deeply processing existential themes and bringing striking subjects such as religion, nudity and the human condition into his novels by refence. His novel Elementary Particles, published in 1998, problematizes the potential return of transhumanist ideas, human desires and technological advances, while depicting a modern society where life has lost its meaning with the advancement of scientific developments. This article aims to reveal the author’s ideas for the future of humanity in a world driven by the increasing use of technology while critically investigating the traces of transhumanism in Houellebecq’s Elementary Particles. After providing an overview of the theory, the study tries to reveal the author’s transhumanist ideas. [ABSTRACT FROM AUTHOR]

The puzzling mechanism of coherent radio emission remains unknown, but fortunately, repeating fast radio bursts (FRBs) provide a precious opportunity, with extremely bright subpulses created in a clear and vacuum‐like pulsar magnetosphere. FRBs are millisecond‐duration signals that are highly dispersed at distant galaxies but with uncertain physical origin(s). Coherent curvature radiation by bunches has already been proposed for repeating FRBs. The charged particles are created during central star's quakes, which can form bunches streaming out along curved magnetic field lines, so as to trigger FRBs. The nature of narrow‐band radiation with time‐frequency drifting can be a natural consequence that bunches could be observed at different times with different curvatures. Additionally, high linear‐polarization can be seen if the line of sight is confined to the beam angle, whereas the emission could be highly circular‐polarized if off‐beam. It is also discussed that pulsar surface may be full of small hills (i.e., zits) which would help producing bulk of energetic bunches for repeating FRBs as well as for rotation‐powered pulsars. [ABSTRACT FROM AUTHOR]

We present results on numerical calculations of the sensitivity coefficients, Q μ, of microwave molecular transitions in 13CH3OH and |${\rm CH_3\, ^{18}OH}$| to the hypothetical variation in the fundamental physical constant μ – the electron-to-proton mass ratio. The invariability of μ in time and space is one of the basic assumptions of the Standard Model of particle physics which can be tested at cosmological scales by means of astronomical observations in the Galaxy and external galaxies. Our calculations show that these two methanol isotopologues can be utilized for such tests since their microwave transitions from the frequency interval 1–100 GHz exhibit a large spread in Q μ values which span a range of −109 ≲ Q μ ≲ 78. We show that the thermal emission lines of 13CH3OH observed in the star-forming region NGC 6334I constrain the variability of μ at a level of 3 × 10−8 (1σ), which is in line with the most stringent upper limits obtained previously from observations of methanol (CH3OH) and other molecules in the Galaxy. [ABSTRACT FROM AUTHOR]

Simple Summary: We connect the Planck scale to the subatomic world without assuming a priori that such a connection exists; we deduce the physical meaning of the famous dimensionless fine-structure constant 1/137 (known simply as 137); we relate the masses of quarks, leptons, and vector bosons to the Higgs mass, i.e., we derive scaling relations for the entire mass ladder of the subatomic world; we deduce from first principles the origin and physical significance of Koide's K = 2 / 3 enigmatic constant and analogous quark and vector boson constants; and we calculate the gauge coupling factors of quarks, leptons, bosons, and the weak interaction in terms of only the Higgs field and Koide's constant. Natural systems of units { U i } need to be overhauled to include the dimensionless coupling constants { α U i } of the natural forces. Otherwise, they cannot quantify all the forces of nature in a unified manner. Thus, each force must furnish a system of units with at least one dimensional and one dimensionless constant. We revisit three natural systems of units (atomic, cosmological, and Planck). The Planck system is easier to rectify, and we do so in this work. The atomic system discounts { G , α G } , thus it cannot account for gravitation. The cosmological system discounts { h , α h } , thus it cannot account for quantum physics. Here, the symbols have their usual meanings; in particular, α G is the gravitational coupling constant and α h is Dirac's fine-structure constant. The speed of light c and the impedance of free space Z 0 are resistive properties imposed by the vacuum itself; thus, they must be present in all systems of units. The upgraded Planck system with fundamental units UPS : = { c , Z 0 , G , α G , h , α h , ... } describes all physical scales in the universe—it is nature's system of units. As such, it reveals a number of properties, most of which have been encountered previously in seemingly disjoint parts of physics and some of which have been designated as mere coincidences. Based on the UPS results, which relate (sub)atomic scales to the Planck scale and the fine-structure constant to the Higgs field, we can state with confidence that no observed or measured physical properties are coincidental in this universe. Furthermore, we derive from first principles Koide's K = 2 / 3 enigmatic constant and additional analogous quark and vector boson constants. These are formal mathematical proofs that justify a posteriori the use of geometric means in deriving the quark/boson mass ladder. This ladder allows us to also calculate the Higgs couplings to the vector bosons and the Weinberg angle in terms of K only, and many of the "free" parameters of the Standard Model of particle physics were previously expected to be determined only from experiments. [ABSTRACT FROM AUTHOR]

The future Laser Interferometer Space Antenna (LISA) for gravitational wave detection in space and the precursor LISA Pathfinder missions rely on metal test masses (TMs) playing the role of free-falling geodesic-reference and interferometer end mirrors. Charge deposited on the TMs by high-energy particles of galactic and solar origin couples with stray electric fields thus perturbing the free-falling geodesic motion. In previous works it has been shown that sub-keV electrons play a relevant role for TM charging. In particular, electrons with energies below 100 eV show a wave-like behavior when impacting on the gold coatings of the TMs and electrode-housing (EH), the capacitive position sensor/actuator that surrounds the TMs. We aim at studying the effects of quantum diffraction of electrons on LISA Pathfinder and LISA TMs and EH gold lattice. We calculate the quantum diffraction probability of electrons with energies < 100 eV impinging on gold lattice from different directions by using the methods of quantum mechanics. The effects of electron quantum diffraction on LISA TM charging are reported here for the first time. This work is also of interest for the second-generation LISA-like space interferometers and for all space missions whose performance relies on free-falling metal test masses.

Natural systems of units {Ui} need to be overhauled to include the dimensionless coupling constants {αUi} of the natural forces. Otherwise, they cannot quantify all the forces of nature in a unified manner. Thus, each force must furnish a system of units with at least one dimensional and one dimensionless constant. We revisit three natural systems of units (atomic, cosmological, and Planck). The Planck system is easier to rectify, and we do so in this work. The atomic system discounts {G,αG}, thus it cannot account for gravitation. The cosmological system discounts {h,αh}, thus it cannot account for quantum physics. Here, the symbols have their usual meanings; in particular, αG is the gravitational coupling constant and αh is Dirac’s fine-structure constant. The speed of light c and the impedance of free space Z0 are resistive properties imposed by the vacuum itself; thus, they must be present in all systems of units. The upgraded Planck system with fundamental units UPS:={c,Z0,G,αG,h,αh,…} describes all physical scales in the universe—it is nature’s system of units. As such, it reveals a number of properties, most of which have been encountered previously in seemingly disjoint parts of physics and some of which have been designated as mere coincidences. Based on the UPS results, which relate (sub)atomic scales to the Planck scale and the fine-structure constant to the Higgs field, we can state with confidence that no observed or measured physical properties are coincidental in this universe. Furthermore, we derive from first principles Koide’s K=2/3 enigmatic constant and additional analogous quark and vector boson constants. These are formal mathematical proofs that justify a posteriori the use of geometric means in deriving the quark/boson mass ladder. This ladder allows us to also calculate the Higgs couplings to the vector bosons and the Weinberg angle in terms of K only, and many of the “free” parameters of the Standard Model of particle physics were previously expected to be determined only from experiments.

The unclear verse "Three Quarks for Muster Mark!", introduced by James Joyce (1882--1941) to his novel entitled Finnegans Wake (first published in 1939), was a literary source for the English word quark denoting 'an elementary particle with a fractional electric charge that is part of a proton, neutron or other interacting elementary particle'. The American physicist Murray Gell-Mann, winner of the Nobel Prize in Physics in 1969, was the first researcher to introduce the English word quark into scientific terminology as early as in 1964. After accepting his hypothesis of quarks in the world science, most physicists adopted the English term quark as standard in the physical terminology of most international languages (e.g. French quark, German Quark, Italian quark, Polish kwark, Portugal quark, Russian ..., Spanish cuark, Turkish kuark, Ukrainian ... 'an elementary particle') and it quickly became a widely recognized internationalism. It is not commonly known that Joyce's verse facetiously imitated loud cries of German dairy women: Drei Mark für muster Quark! (literally "Three Marks for an excellent curd!"). In other words, E. quark 'an elementary particle' is motivated by the German term Quark m. 'weiser Käse / curd, white cheese', metaphorically 'trifle, nonsense, trash, worthless thing', which -- according to most German and Slavic etymologists -- represents an obvious Slavic borrowing (especially a Polish or Lower Sorbian loanword), cf. Pol. twaróg, dial. kwaruk m. 'curd, white cheese' (< Proto-Slavic *tvarogъ m. 'id.'). It is suggested that the specialized term kwark represents the so called back-borrowing in the Polish language. [ABSTRACT FROM AUTHOR]

Summary: Debris dams have a crucial role in consolidation of river basins and allow erosion control, flood protection in mountainous areas. Many of these infrastructures have operated over five decades, thus structural health monitoring (SHM) of these infrastructures became timely due to their aging. Utilizing new techniques is required for inspecting a large number of dams and deciding about their reinforcement or reconstruction. In this work, we propose cosmic-ray muography as a complementary tool for the SHM of debris dams. We conducted the first muographic surveying of a sabo check dam in the Karasu River, Gunma, Japan. The average mass density image was produced with a spatial resolution of 0.5 m through the dam. The comparison of density data reconstructed by muography and gamma-ray logging suggest the internal deterioration of dam in the region where cement released out from the embankment body.

Magnetic fields are everywhere in the Universe and in our everyday life and many processes are affected by their presence, generating a rich phenomenology that depends also on other possible external agents. We review here some results, both from our workgroup and from other research groups, about the effect of magnetic fields on particles interaction processes, focusing mainly on recent results, but without losing sight on early seminal works on this topic. A vast assortment of physical situations and of analytical and numerical approaches can be found in the literature in this subject, making the comparison between them not straightforward. Our aim is to focus attention on differences and similarities between the different situations and approaches, looking for a systematization scheme that could be predictive, once the role played by each physical ingredient could be understood. The main purpose of this work is to find some physical explanations of the ongoing processes. [ABSTRACT FROM AUTHOR]

The extremely successful Standard Model of Particle Physics allows one to define the so-called Elementary Particles. From another point of view, how can we think of them? What kind of a status can be attributed to Elementary Particles and their associated quantised fields? Beyond the unprecedented efficiency and reach of quantum field theories, the current paper attempts at understanding the nature of what these theories describe, the enigmatic reality of the quantum world. [ABSTRACT FROM AUTHOR]

In the current article, utilizing the theory of quantization of time and space and the internal structure of elementary particles, the radiation spectrum of the excited hydrogen atom is calculated theoretically. By doing this, the electron movement parameters in the hydrogen atom have been stated in a novel way, and via generalizing these calculations, the excited states of other atoms can be calculated. It can be shown that during the transfer of the electron from a higher level to a lower one, what is the state of the electron in terms of momentum, energy, time, and length. [ABSTRACT FROM AUTHOR]

High-energy charged particles are considered particularly hazardous components of the space radiation environment. Such particles include fully ionized energetic nuclei of helium, silicon, and oxygen, among others. Exposure to charged particles causes reactive oxygen species production, which has been shown to result in neuronal dysfunction and myelin degeneration. Here we demonstrate that mice exposed to high-energy charged particles exhibited alterations in dendritic spine density in the hippocampus, with a significant decrease of thin spines in mice exposed to helium, oxygen, and silicon, compared to sham-irradiated controls. Electron microscopy confirmed these findings and revealed a significant decrease in overall synapse density and in nonperforated synapse density, with helium and silicon exhibiting more detrimental effects than oxygen. Degeneration of myelin was also evident in exposed mice with significant changes in the percentage of myelinated axons and g-ratios. Our data demonstrate that exposure to all types of high-energy charged particles have a detrimental effect, with helium and silicon having more synaptotoxic effects than oxygen. These results have important implications for the integrity of the central nervous system and the cognitive health of astronauts after prolonged periods of space exploration.

In this paper a sphere fiber bundle structure underlying the Standard Model of Particle Physics is developed. The developed bundle framework is shown to contain mathematical structures naturally suited for modeling the Standard Model’s elementary particles and fields.This modeling yields numerous results across the spectrum of physics, including: a resolution to the family problem, explanation of the 6-6 lepton–quark split in nature, a spacetime structural explanation of dark matter and energy, prediction of repulsive gravitational effects occurring in localized regions of space maintained at energies O(1015K), a modeling of the SM elementary particles as vibrating closed loops in spacetime, elimination of the fermionic QFT VEV catastrophe, the unveiling of a grand unification model at odds with standard GUT models, prediction of Dirac-style magnetic monopoles and of a quark-gluon and quasi-quark-gluon plasma near inception of the universe, a topological explanation for quark confinement, resolution to the cosmological constant problem, and a presentation of the model’s topology of quantum entanglement which reconciles relativistic locality with quantum non-locality.

In the late age of developing quantum mechanics, Lev Landau made great efforts to understand the nature of matter, even stellar matter, by applying the quantum theory. Ninety years ago, he published his idea of "neutron" star, which burst upon him during his visit over Europe in the previous year. The key point that motivated Landau to write the paper is to make a state with lower energy for "gigantic nucleus", avoiding extremely high kinematic energy of electron due to the new Fermi–Dirac statistics at that time. Landau had no alternative but to neutralize by "combining a proton and an electron" before the discovery of neutron. However, our understanding of the nature has fundamentally improved today, and another way (strangeonization) could also embody neutralization and thus a low‐energy state that Landau had in mind, which could further make unprecedented opportunities in this multi‐messenger era of astronomy. Strangeon matter in "old" physics may impact dramatically today's physics, from compact stars initiated by Landau, to cosmic rays and dark matter. In this essay, we are making briefly the origin and development of neutron star concept to reform radically, to remember Landau's substantial contribution to astrophysics and to recall those peculiar memories. [ABSTRACT FROM AUTHOR]

В современном обществе меняются способы получения образования с акцентом на усиление роли интернет-сетей как источника информации. Помимо этого, набирают силу диалоговые методы обучения. В течение последних двух лет вопросы дистанционного обучения стали особенно актуальными. Извлечь информацию из Сети еще не значит приобрести полноценные знания, поэтому приходят на помощь сетевые образовательные сервисы. Авторы предлагают использовать для дистантного изучения физико-математических дисциплин модульную объективно ориентированную динамическую обучающую среду OpenSystem, имеющую ряд возможностей для структурирования материала и управления учебной деятельностью студентов. Существующая потребность дистанционного изучения студентами ряда дисциплин требует разработки соответствующих методических материалов. Примером в нашем случае служит дистантная реализация авторского курса «Физика атомного ядра» для студентов бакалавриата физико-математического факультета педагогического университета.

Based on the smallest physical constant of the product of space interval, time interval, and energy, the fractal quantum gravity (FQG) theory has demonstrated that every particle or physical system consists of these smallest units in fractal structures. The general relativity is an approximation of the FQG equation when the quantum effect is negligible, while the quantum theory is an approximation of the FQG equation when the interaction between space, time, and energy is very weak or negligible. The stationary-action principle can be derived from the FQG equation. The mass range of possibly existing elementary particles and an accelerating expansion evolution model of the universe can be obtained through the FQG equation. This FQG equation satisfied almost all the requirements of a quantum gravity theory and there is no free constant needed in the FQG theory. It looks promising that the FQG theory may offer a novel way to calculate all the free constants in the Standard Model of particle physics and general relativity.

We present a search for coincidence between IceCube TeV neutrinos and fast radio bursts (FRBs). During the search period from 2010 May 31 to 2016 May 12, a total of 29 FRBs with 13 unique locations have been detected in the whole sky. An unbinned maximum likelihood method was used to search for spatial and temporal coincidence between neutrinos and FRBs in expanding time windows, in both the northern and southern hemispheres. No significant correlation was found in six years of IceCube data. Therefore, we set upper limits on neutrino fluence emitted by FRBs as a function of time window duration. We set the most stringent limit obtained to date on neutrino fluence from FRBs with an E -2 energy spectrum assumed, which is 0.0021 GeV cm-2 per burst for emission timescales up to ∼102 s from the northern hemisphere stacking search.

In the last few decennium, the acquaintance between algebraic hyperstructures and fuzzy sets have been considered for its theoretical as well as applications in various fields. Fuzzy hyperstructures are fascinating research topic and substantial amount of researches have been undergoing as of now. As a consequence, fuzzy hyperlattice was introduced by Pengfei He, Xiaolong Xin. But the applications on fuzzy hyperlattice are not defined so far. By scrutinizing the fuzzy hyperlattice, our objective is to present some applications of fuzzy hyperlattice in Biological and Physical Sciences. We find the first and second applications in dihybrid cross of Drosophila melanogaster (housefly) and Pisum sativum (Peas), respectively. Third application is in particle Physics (Elementary particles interaction).

The mystery associated with a proposed Dark Sector of phenomena that are separate from the standard model of particle physics is described. A Dark Sector may possess matter particles, force carriers which mediate their interactions, and new interactions and symmetries that are beyond the standard model of particle physics. Various approaches for Dark Sector searches are described, including those at the energy frontier at the Large Hadron Collider, in astrophysical interactions with both terrestrial experiments and those in space-born platforms. Searches using low energy photons from microwave energies in cryogenic environments to x-ray energies are also described. While there is no noncontroversial evidence for Dark Sector phenomena presently, new searches with more modern equipment and analysis methods are exploring regions of phase space that have not been available before now, indicating ongoing interest and excitement in this research. [ABSTRACT FROM AUTHOR]

In this presented article, methodical proposals and recommendations on the formation of basic and special competencies related to modern models of the atomic nucleus in the teaching of the physics course in higher educational institutions have been developed. In addition, the article presents methodical recommendations on the organization of lesson processes using visual multimedia educational tools on the basis of the “Drop” model of the atomic nucleus. The article presents and analyzes interesting questions about the basic physical laws of nuclear models, test tasks, independent work, and the methodology of using virtual experiments in teaching the physics of the atomic nucleus and elementary particles. [ABSTRACT FROM AUTHOR]

Gravitational weak lensing by dark matter haloes leads to a measurable imprint in the shear correlation function of galaxies. Fuzzy dark matter (FDM), composed of ultralight axion-like particles of mass m ∼ 10−22 eV, suppresses the matter power spectrum and shear correlation with respect to standard cold dark matter. We model the effect of FDM on cosmic shear using the optimized halo model HMCode , accounting for additional suppression of the mass function and halo concentration in FDM as observed in N -body simulations. We combine Dark Energy Survey Year 1 (DES-Y1) data with the Planck cosmic microwave background anisotropies to search for shear correlation suppression caused by FDM. We find no evidence of suppression compared to the preferred cold dark matter model, and thus set a new lower limit to the FDM particle mass. Using a log-flat prior and marginalizing over uncertainties related to the non-linear model of FDM, we find a new, independent 95 per cent C.L. lower limit log10 m > −23 combining Planck and DES-Y1 shear, an improvement of almost two orders of magnitude on the mass bound relative to CMB-only constraints. Our analysis is largely independent of baryonic modelling, and of previous limits to FDM covering this mass range. Our analysis highlights the most important aspects of the FDM non-linear model for future investigation. The limit to FDM from weak lensing could be improved by up to three orders of magnitude with |$\mathcal {O}(0.1)$| arcmin cosmic shear angular resolution, if FDM and baryonic feedback can be simultaneously modelled to high precision in the halo model. [ABSTRACT FROM AUTHOR]

We discuss the case against Factorism, which is the standard assumption in quantum mechanics that the labels of the ⊗ -factor Hilbert-spaces in direct-product Hilbert-spaces of composite physical systems of similar particles refer to particles, either directly or descriptively. We distinguish different versions of Factorism and argue for their truth or falsehood. In particular, by introducing the concepts of snapshot Hilbert-space and Schrödinger-movie, we demonstrate that there are Hilbert-spaces and ⊗ -factorisations where the labels do refer, even descriptively, to similar particles, which renders them probabilistically absolutely discernible. [ABSTRACT FROM AUTHOR]

This review describes the current status of precision quantum chromodynamics (QCD) studies at the LHC. We introduce the main experimental and theoretical methods, and we discuss their cross-stimulated developments and recent advances. The different types of QCD observables that are measured at the LHC, including cross sections and event- and jet-level properties, for various final states, are summarized. Their relation to fundamental QCD dynamics and their impact on Standard Model parameter determinations are discussed using specific examples. The impact of QCD-related observables on direct and indirect searches for rare processes within and New Physics beyond the Standard Model is outlined. [ABSTRACT FROM AUTHOR]

Black holes play an important role in linking microphysics with macrophysics, with those of the Planck mass (MP ∼ 10−5 g) featuring in any theory of quantum gravity. In particular, the Compton-Schwarzschild correspondence posits a smooth transition between the Compton wavelength (RC ∝ 1/M) below the Planck mass and the Schwarzschild radius (RS ∝ M) above it. The duality between RC and RS implies a form of the Generalized Uncertainty Principle (GUP) and suggests that elementary particles may be sub-Planckian black holes. The simplest possibility is that the ADM mass has the form M+βMP2/M for some constant β and this model can be extended to charged and rotating black holes, clearly relevant to elementary particles. Another possibility is that sub-Planckian black holes may arise in loop quantum gravity and this explicitly links black holes and elementary particles. Higher dimensions may modify both proposals. If there are n extra dimensions, all with the same compactification scale, one expects RS ∝ M1/(1+n) below this scale but RC depends on the form of the higher-dimensional wave-function. If it is spherically symmetric, then RC ∝ M−1, so duality is broken and the Planck mass is reduced, allowing the possibility of TeV quantum gravity. If the wave-function is pancaked in the extra dimensions, RC ∝ M−1/(1+n) and so duality is preserved but the Planck mass is unchanged.

In this work, we revisit five different point sources within or behind galaxy clusters to constrain the coupling constant between axion-like particles (ALPs) and photons. We use three distinct machine learning (ML) techniques and compare our results with a standard χ2 analysis. For the first time, we apply approximate Bayesian computation to search for ALPs and find consistently good performance across ML classifiers. Further, we apply more realistic 3D magnetic field simulations of galaxy clusters and compare our results with previously used 1D simulations. We find constraints on the ALP-photon coupling at the level of state-of-the-art bounds with |$g_{a\gamma \gamma } \lesssim 0.6 \times 10^{-12} \, \rm{GeV}^{-1}$|⁠ , hence improving on previous constraints obtained from the same observations. [ABSTRACT FROM AUTHOR]

We review the work of Klaus Hasselmann, one of three recipients of the Nobel Prize in Physics 2021, from the perspective of computational science and engineering (CSE). In addition to highlighting Hasselmann's extensive contributions to climate science, we shine a light on his groundbreaking work in ocean surface wave dynamics and prediction, which preceded his career in climate research. Early on, Hasselmann also gained a strong interest in elementary particle physics, which led him to develop, in his spare time, a unified theory of particles and fields, and which we outline here. With this review we hope to entice computational scientists to delve deeper into Hasselmann's extraordinarily broad work at the interface of climate physics, mathematics, and scientific computing, and to appreciate the central role that CSE continues to play in climate research. [ABSTRACT FROM AUTHOR]

The Black Hills State University Underground Campus (BHUC) houses a low background counting facility on the 4850' level of the Sanford Underground Research Facility. There are currently four ultra-low background, high-purity germanium detectors installed in the BHUC and it is anticipated four more detectors will be installed within a year. In total, the BHUC will be able to accommodate up to twelve detectors with space inside a class 1000 cleanroom, an automated liquid nitrogen fill system, on-site personnel assistance and other required utilities.

Based on Mie scattering theory, fractal theory, the generalized multiparticle Mie model and the attenuated total reflectance infrared spectroscopy method, this paper aimed to explore the influence of different distribution morphologies of semiconductor nanoparticles on their radiation properties. The results revealed that (1) the symmetry and fluctuation amplitude of the scattering direction of the SiC elementary particles, with a diameter of 100 nm, and the cluster particles were related to the wavelength, particle size and agglomeration state. (2) The particle size distribution had a significant effect on the spectral extinction performance of the SiC particles, especially when λ > 10 μm, which can be greatly strengthened by increasing the proportion of large-scale particles. (3) The influence of SiC particle clusters on their spectral extinction was directly related to the cluster size and wavelength. When λ < 10 μm, small-scale cluster particles showed lower extinction performances; however, the absorption and scattering factors increased with the increase in cluster size while λ > 10 μm, and the extinction performance significantly improved. In summary, the quantitative changes in the microscale and structure, as well as the distribution states, had a significant impact on the infrared spectral characteristics of the particles, and we expect to adjust the particle size distribution to obtain desired radiation properties. [ABSTRACT FROM AUTHOR]

These notes present an introduction to the method of geometric quantization. We discuss the main theorems in a style suitable for a theoretical physicist with an eye towards the physical motivation and the interpretation of the geometric construction as providing a solution to Dirac's axioms of quantization. We provide in detail the examples of free relativistic particles, their corresponding quantum fields, and the bosonic string using formalism of double field theory. This paper is based on lectures written by Gabriel Cardoso. [ABSTRACT FROM AUTHOR]

We estimate limits on non-universal coupling of hypothetical hidden fields to standard matter by evaluating the fractional changes in the electron-to-proton mass ratio, μ = m e/ m p, based on observations of Class I methanol masers distributed in the Milky Way disc over the range of the Galactocentric distances |$4 \lesssim R \lesssim 12$| kpc. The velocity offsets Δ V  = V 44 − V 95 measured between the 44- and 95-GHz methanol lines provide, so far, one of the most stringent constraints on the spatial gradient k μ ≡ d(Δμ/μ)/d R < 2 × 10−9 kpc−1 and the upper limit on Δμ/μ <2 × 10−8, where Δμ/μ =  |$(\mu _{\rm \scriptscriptstyle obs}-\mu _{\rm \scriptscriptstyle lab})/\mu _{\rm \scriptscriptstyle lab}$|⁠. We also find that the offsets Δ V are clustered into two groups which are separated by |$\delta _{\scriptscriptstyle \Delta V} = 0.022 \pm 0.003$| km s−1 (1σ confidence level). The grouping is most probably due to the dominance of different hyperfine transitions in the 44- and 95-GHz methanol maser emission. Which transition becomes favoured is determined by an alignment (polarization) of the nuclear spins of the four hydrogen atoms in the methanol molecule. This result confirms that there are preferred hyperfine transitions involved in the methanol maser action. [ABSTRACT FROM AUTHOR]

It is agreed that before the creation of particles, space was completely devoid of matter and radiation. In this study, we assume that the absolute void comprises 4 dimensions, namely 3 spatial dimensions and a force equivalent representing the factor of change among the elementary dimensions. Our hypothesis is based on the expansion of the spatial dimensions and the subsequent space instability. We demonstrated that when the equivalent outward force strength exceeds a critical limit, it collapses inwardly to restore the equilibrium of the system. Subsequently, the void inside the collapsed force equivalent acts as a void in a confined system, and the energy of the system remains conserved at all stages. With the decrease in the spatial dimensions owing to the collapse, the energy density increases, and at the final stage, the energy in the confined system becomes concentrated, thereby forming a solid state of energy. In this solid state of energy, a particle becomes the source of the elementary particles. The created high-energy sources are controlled by the internal and external forces of the source and all the entities in its external force field until equilibrium is reached. This article gives a summary of the Big Bang theory and its problems, which are further discussed in detail. This article will help in understanding how elementary dimensions play a role in the formation of elementary particles. Quark-gluon plasma, inflation, gravitational collapse, and gravitational lensing provide evidence that supports the elementary dimensions theory presented in this paper.

When the vacuum like energy of the Higgs potential within the standard model undergoes electroweak phase transition, an influx of entropy into the primordial plasma can lead to a significant dilution of frozen out dark matter density that was already present before the onset of the phase transition. The same effect can take place if the early universe was dominated by primordial black holes of small mass, evaporating before the period of Big Bang Nucleosynthesis. In this paper, we calculate the dilution factor for the above-mentioned scenarios. [ABSTRACT FROM AUTHOR]

In the following, the oscillations and potentials of mesons and baryons are examined and analyzed in detail. The oscillations result from a simple formula that describes the resonance energy at which the corresponding particle can absorb energy and thus appear. The potentials describe three mechanisms that describe the fine splitting of the masses of the elementary particles. These potentials can be read off and derived from the experimentally determined masses of the elementary particles as coefficients. The three mechanisms are internal mass charge binding energy, external mass charge binding energy, and Coulomb interaction. [ABSTRACT FROM AUTHOR]

The mystery associated with a proposed Dark Sector of phenomena that are separate from the standard model of particle physics is described. A Dark Sector may possess matter particles, force carriers which mediate their interactions, and new interactions and symmetries that are beyond the standard model of particle physics. Various approaches for Dark Sector searches are described, including those at the energy frontier at the Large Hadron Collider, in astrophysical interactions with both terrestrial experiments and those in space-born platforms. Searches using low energy photons from microwave energies in cryogenic environments to x-ray energies are also described. While there is no noncontroversial evidence for Dark Sector phenomena presently, new searches with more modern equipment and analysis methods are exploring regions of phase space that have not been available before now, indicating ongoing interest and excitement in this research.