Article
Physics, Particles & Fields
Polina Petriakova, Arkady A. Popov, Sergey G. Rubin
Summary: This paper discusses the origin of small parameters and aims to explain the Hierarchy problem. Flexible extra dimensions play a crucial role in the formation of physical parameters. The evolution of multidimensional metric starts from the Planck scale and ends with a static extra-dimensional metric and a 4-dimensional de Sitter space at high energies, leading to exponentially produced causally disconnected universes. Quantum fluctuations independently distort the metric within these universes, causing inflationary processes. Some universes asymptotically tend towards states characterized by small Hubble parameters. The explanation for the effective parameter reduction in the Higgs sector of the Standard Model lies in the presence of small-amplitude distributions of a scalar field in a fraction of these universes.
EUROPEAN PHYSICAL JOURNAL C
(2023)
Article
Astronomy & Astrophysics
Gabriela Barenboim, Nikita Blinov, Albert Stebbins
Summary: The study suggests that the evolution of the universe before Big Bang Nucleosynthesis may have experienced an early phase of matter domination, leading to the growth of dark matter structures. Contrary to the assumptions of standard cosmology, the formation of dark matter structures occurs earlier than expected, with most dark matter being bound in microhalos.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2021)
Article
Astronomy & Astrophysics
Thomas Biekoetter, Sven Heinemeyer, Jose Miguel No, Maria Olalla Olea-Romacho, Georg Weiglein
Summary: We analyze the thermal history of the 2HDM and find that the presence of vacuum trapping impedes a first-order electroweak phase transition in certain parameter regions. In the regions where the transition does occur, the parameter space for a detectable stochastic gravitational wave signal is constrained and will be well probed by the HL-LHC and measurements of the self-coupling of the Higgs boson at 125 GeV. The ILC has the ability to probe the majority of the 2HDM parameter space with high precision through measurements of the self-coupling.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2023)
Review
Astronomy & Astrophysics
Valerio Bozza
Summary: This paper reviews the evolution of perturbations in bouncing cosmologies and discusses significant attempts to reconcile predicted spectra with observations. Bouncing cosmologies, particularly the pre-Big Bang scenario, are viable alternatives to inflation that can help address current theoretical and observational tensions.
Article
Astronomy & Astrophysics
Manuel Drees, Bardia Najjari
Summary: In this study, we focus on the spectrum of energetic particles originating from the decay of massive progenitors during thermalization, considering factors such as background temperature, IR cutoff, and the LPM effect. By solving the resulting integral equation numerically and constructing an accurate analytical fit of the solutions, we obtain precise results.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2021)
Article
Astronomy & Astrophysics
Daniel G. Figueroa, Adrien Florio, Francisco Torrenti, Wessel Valkenburg
Summary: In this paper, lattice techniques for simulating scalar and gauge field dynamics in an expanding universe are comprehensively discussed. The discretization of field theories, numerical algorithms, and lattice formulations for interacting scalar fields and gauge theories are presented. Symplectic integrators with different accuracy levels are provided for each case, along with relevant observables and constraints. The article also introduces the theoretical basis for the CosmoLattice code, a MPI-based package for simulating the non-linear evolution of field theories in an expanding universe.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2021)
Article
Astronomy & Astrophysics
Thomas Biekoetter, Sven Heinemeyer, Jose Miguel No, Maria Olalla Olea, Georg Weiglein
Summary: Extensions of the Higgs sector of the Standard Model can lead to a rich cosmological history around the electroweak scale, with the possibility of various phenomena such as non-restoration of electroweak symmetry or vacuum trapping. By focusing on the N2HDM of type II and considering theoretical and experimental constraints, scenarios of electroweak symmetry non-restoration, vacuum trapping, and first-order phase transition in the thermal history of the Universe are identified. Despite the presence of a global electroweak minimum in the scalar potential at zero temperature, the physical viability of the N2HDM parameter space is not guaranteed, emphasizing the importance of analyzing tunneling probability for reliable predictions of the Universe's thermal history.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2021)
Article
Astronomy & Astrophysics
Peter Athron, Csaba Balazs, Lachlan Morris
Summary: We investigate rarely explored details of supercooled cosmological first-order phase transitions at the electroweak scale, which may lead to strong gravitational wave signals or explain the cosmic baryon asymmetry. We argue that the nucleation temperature is not fundamental or essential in phase transition analysis and provide empirical bounds on the bubble wall velocity for the completion of a transition. We also propose the use of percolation temperature as a reference temperature for gravitational wave production.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2023)
Article
Astronomy & Astrophysics
Glauber C. Dorsch, Stephan J. Huber, Thomas Konstandin
Summary: This paper revisits the computation of bubble wall friction during a cosmological first-order phase transition and solves the linearized Boltzmann equation using an extended fluid ansatz. A singularity is discovered in the fluctuations of background species as the wall approaches the speed of sound. By using hydrodynamics, it is argued that a discontinuity across the speed of sound is expected and manifests itself as the singularity in the solution of the linearized system. This result is discussed in comparison with alternative approaches, which find a regular behavior of the friction for all velocities.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2022)
Article
Astronomy & Astrophysics
Shyam Balaji, Michael Spannowsky, Carlos Tamarit
Summary: In first-order cosmological phase transitions, subluminal bubble expansion requires out-of-equilibrium interactions with the plasma, which can be understood from the conservation of entropy in local equilibrium, leading to subluminal speeds for both deflagrations and detonations. Friction effect arises from the background field dependence of the entropy density in the plasma, and can be accounted for by imposing local conservation of stress-energy and including field-dependent thermal contributions to the effective potential. Illustrative calculations for a first-order electroweak transition in a Standard Model extension with additional scalar fields demonstrate these effects.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2021)
Article
Astronomy & Astrophysics
Marco Hufnagel, Xun-Jie Xu
Summary: In the presence of interactions between neutrinos and dark matter, this study investigates the implications for the evolution of both dark matter and neutrinos in the early Universe. It shows that the future cosmic neutrino detection experiment PTOLEMY might be sensitive to neutrino signals that originate from dark matter annihilation in this model.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2022)
Article
Astronomy & Astrophysics
Mariana Carrillo Gonzalez, Qiuyue Liang, Jeremy Sakstein, Mark Trodden
Summary: The tension between measurements of the Hubble constant at different redshifts may indicate new physics at play in the early universe, potentially involving early dark energy and scalar field interactions with standard model neutrinos. A neutrino-assisted early dark energy model is proposed to explain the coincidence between different epochs, with detailed analysis and constraints needed for validation. This scenario opens up new avenues for testing using cosmological data sets.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2021)
Article
Astronomy & Astrophysics
Guillem Domenech, Misao Sasaki
Summary: This study focuses on the interaction between Fermi gas and scalar field in cosmology, exploring important results under the massless limit of the scalar field, including solutions induced by Yukawa interaction and decay of energy density as radiation. The research indicates that regardless of whether fermions are initially relativistic or non-relativistic, their energy densities decay into radiation.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2021)
Article
Astronomy & Astrophysics
Chong-Bin Chen, Jiro Soda
Summary: The study indicates that destabilization of standard slow-roll inflation commonly occurs in multi-scalar-gauge field inflationary scenarios.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2021)
Article
Astronomy & Astrophysics
Prolay Chanda, James Unwin
Summary: In this paper, the scenario in which Asymmetric Dark Matter (ADM) decouples from the Standard Model thermal bath during an early period of matter domination is explored. Model independent analysis and a specific example in the context of an elegant SO(10) implementation are presented and contrasted with conventional ADM models. The prospects for superheavy ADM in this setting are discussed in the concluding remarks.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2021)
Article
Astronomy & Astrophysics
Carlos Heredia, Ivan Kolar, Josep Llosa, Francisco Jose Maldonado Torralba, Anupam Mazumdar
Summary: This article aims to transform the infinite-order Lagrangian density for ghost-free infinite-derivative linearized gravity into a non-local form using the theory of generalized functions and the Fourier transform in the space of tempered distributions S'.
CLASSICAL AND QUANTUM GRAVITY
(2022)
Article
Physics, Particles & Fields
Sougato Bose, Anupam Mazumdar, Marko Toros
Summary: The coupling between gravity and matter provides a hint for the infrared length scale in theories of gravity. By studying the relationship between gravitons and the number of particles, this length scale can be determined, which is also applicable in higher curvature theories of gravity.
Article
Astronomy & Astrophysics
Michele Cicoli, Veronica Guidetti, Francesco Muia, Francisco G. Pedro, Gian Paolo Vacca
Summary: We discuss the usefulness and theoretical consistency of different entropy variables used in the literature to describe isocurvature perturbations in multifield inflationary models. We clarify which is the proper entropy variable to be used to compare with observational constraints. We find that commonly used variables can lead to wrong results or unphysical destabilisation effects for cases with light kinetically coupled spectator fields.
CLASSICAL AND QUANTUM GRAVITY
(2023)
Article
Physics, Particles & Fields
Michele Cicoli, Matteo Licheri, Anshuman Maharana, Kajal Singh, Kuver Sinha
Summary: In this study, the joint distribution of the gravitino mass and the cosmological constant in KKLT and LVS models with anti-D3 brane uplifting is obtained using the nilpotent goldstino formalism. Moduli stabilisation of both complex structure and Kahler moduli is considered, and the distributions of the flux superpotential, string coupling, and hierarchies of warped throats are taken as key inputs. The results show that, in the limit of zero cosmological constant, both KKLT and LVS models have distributions that favor lower scales of supersymmetry breaking.
JOURNAL OF HIGH ENERGY PHYSICS
(2023)
Article
Education & Educational Research
K. K. Mashood, Arvind Kumar, Anwesh Mazumdar
Summary: This paper presents an exploratory study of student understanding of approximations in college physics. The findings reveal significant student difficulties in identifying dimensionless ratios, understanding the order of approximation, and comprehending the order of infinitesimal in calculus-based derivations. These results have direct pedagogic implications.
INTERNATIONAL JOURNAL OF MATHEMATICAL EDUCATION IN SCIENCE AND TECHNOLOGY
(2023)
Article
Physics, Multidisciplinary
Sougato Bose, Anupam Mazumdar, Martine Schut, Marko Toros
Summary: The Einstein equivalence principle, which is based on the equality of gravitational and inertial mass, has been extensively tested and proven with high precision in classical setups. However, in this study, a quantum protocol is proposed to test the equivalence principle in the quantum regime by creating large spatial superposition states. This unique protocol provides a way to test the generalization of the weak equivalence principle through the observation of quantum entanglement.
Article
Physics, Particles & Fields
Michele Cicoli, Matteo Licheri, Ratul Mahanta, Evan McDonough, Francisco G. Pedro, Marco Scalisi
Summary: Early Dark Energy (EDE) is a potential model for resolving the Hubble Tension and is informed by Cosmic Microwave Background data. It can be realized in type IIB string theory with the EDE field identified as a C-4 or C-2 axion, and with the moduli stabilization achieved in either KKLT or the Large Volume Scenario. Natural hierarchy between the EDE energy scale and other fields can be achieved in a controlled effective field theory. The most promising EDE candidates are the C-2 axions in LVS with 3 non-perturbative corrections to the superpotential generated by gaugino condensation on D7-branes with non-zero world-volume fluxes.
JOURNAL OF HIGH ENERGY PHYSICS
(2023)
Article
Astronomy & Astrophysics
Meng-Zhi Wu, Marko Toro, Sougato Bose, Anupam Mazumdar
Summary: In this paper, we establish a three-dimensional model and theoretically investigate the achievable sensitivities of matter-wave interferometers for gravity experiments. We also study the application of mesoscopic interference for metric and curvature and gravitational-wave detection, and quantify its sensitivity to gravity gradients using frequency-space analysis. The minimum detectable mass of objects near Earth-based experiments and space debris in proximity of satellites is estimated as a function of their distance, velocity, and orientation.
Article
Optics
Run Zhou, Ryan J. Marshman, Sougato Bose, Anupam Mazumdar
Summary: Placing a large mass in a large spatial superposition is a challenge for testing the quantum nature of gravity. The proposed methods so far have limitations due to the mass-dependence of spatial splitting. This paper presents a method of achieving mass-independent enhancement of superposition using diamagnetic repulsion from current-carrying wires.
Article
Physics, Multidisciplinary
Bin Yi, Urbasi Sinha, Dipankar Home, Anupam Mazumdar, Sougato Bose
Summary: This article introduces the use of massive spatial qubits as a new tool to demonstrate the nonclassicality of the center of mass state of a macroscopic object and the interactions between macroscopic objects. The study shows that by measuring the position of the encoded spatial qubits at different durations of free evolution, accurate measurements can be obtained.
PHYSICAL REVIEW RESEARCH
(2023)
Article
Astronomy & Astrophysics
Peter F. Barker, Sougato Bose, Ryan J. Marshman, Anupam Mazumdar
Summary: Quantum entanglement offers a new method for testing short distance physics in nonrelativistic scenarios. By bringing two charged massive particle interferometers in close proximity, we can potentially probe new physics through the entanglement dynamics. This protocol enables us to constrain the range and nature of new physical effects.
Article
Physics, Multidisciplinary
Run Zhou, Ryan J. Marshman, Sougato Bose, Anupam Mazumdar
Summary: This paper investigates the acceleration of two spin states of a macroscopic nanocrystal by utilizing a non-uniform nonlinear magnetic field in a laboratory. The research shows that a desired superposition state can be created within a short time by catapulting and recombining the trajectories of the two spin states under a moderate magnetic field gradient. Furthermore, the precision of the magnetic field is crucial for achieving a 99% spin coherence confidence level at the moment of interference.
PHYSICAL REVIEW RESEARCH
(2022)
Article
Astronomy & Astrophysics
Arnab Dasgupta, P. S. Bhupal Dev, Anish Ghoshal, Anupam Mazumdar
Summary: This study analyzes the classically scale-invariant B - L model in the context of resonant leptogenesis. The findings suggest that the parameter space of the model can be effectively probed through the detection of gravitational waves.
Article
Astronomy & Astrophysics
Ulrich K. Beckering Vinckers, Alvaro de la Cruz-Dombriz, Ivan Kolar, Francisco J. Maldonado Torralba, Anupam Mazumdar
Summary: In this study, we introduce ghost-free infinite-derivative extensions of spherically reduced gravity and CGHS theory in two-dimensional spacetime. We diagonalize the quadratic action for field perturbations under specific gauge choices and obtain ghost-free infinite-derivative modifications of SRG and CGHS theories. Nonlocal modifications to the linearized Schwarzschild and black-hole solutions are analyzed within these modified theories.