Aharonov-Bohm Research Articles

Bounds on the charge of the graviton using gravitational wave observations

If the graviton possesses a non-zero charge qg , gravitational waves (GW) originating from astrophysical sources would experience an additional time delay due to intergalactic magnetic fields. This would result in a modification of the phase evolution of the observed GW signal similar to the effect induced by a massive graviton. As a result, we can reinterpret the most recent upper limits on the graviton's mass as constraints on the joint mass-charge parameter space, finding |qg |/e < 3 × 10-34 where e represents the charge of an electron. Additionally, we illustrate that a charged graviton would introduce a constant phase difference in the gravitational waves detected by two spatially separated GW detectors due to the Aharonov-Bohm effect. Using the non-observation of such a phase difference for the GW event GW190814, we establish a mass-independent constraint |qg |/e < 2 × 10-26. To the best of our knowledge, our results constitute the first-ever bounds on the charge of the graviton. We also discuss various caveats involved in our measurements and prospects for strengthening these bounds with future GW observations.

Spectra and Thermodynamic Properties of Zig-Zag Single – Walled Carbon Nanotube with Deng–Fan–Hulthen Potential

A theoretical investigation of the spectra and thermodynamic properties of zig-zag single-walled carbon nanotubes (6,0) is carried out within the framework of the Deng–Fan–Hulthen potential. We solved the Schr¨odinger wave equation analytically in the presence of magnetic and Aharonov–Bohm (AB) flux fields using the Nikiforov–Uvarov (NU) method and obtained the energy eigenvalues and eigenfunctions. It is observed that, in the absence of both magnetic and AB fields, there is a degeneracy in the energy spectra. The presence of the magnetic and AB flux fields led to an increase in the energy eigenvalues. The combined presence of both fields removed the degeneracy noticed in the system. We calculated the partition function and used it to evaluate the thermodynamic properties such as the mean energy, free energy, and entropy in respect to the temperature, magnetic field, AB flux field and the quantum numbers.

Emergence of the Molecular Geometric Phase from Exact Electron-Nuclear Dynamics.

Geometric phases play a crucial role in diverse fields. In molecules, they appear when a reaction path encircles an intersection between adiabatic potential energy surfaces and the molecular wave function experiences quantum-mechanical interference effects. This intriguing effect, closely resembling the magnetic Aharonov-Bohm effect, crucially relies on the adiabatic description of the dynamics, and it is an open issue whether and how it persists in an exact quantum dynamical framework. Recent works suggest that the molecular geometric phase is an artifact of the adiabatic approximation, thereby challenging the entire concept. Here, building upon a recent investigation (Martinazzo, R.; Burghardt, I. Phys. Rev. Lett. 2024, 132, 243002), we address this issue using the exact factorization of the total wave function. We introduce instantaneous gauge-invariant phases separately for the electrons and nuclei and use them to monitor the phase difference between the trailing edges of a wavepacket encircling a conical intersection between adiabatic surfaces. The transition from the time-dependent open-path phase differences to the closed-path limit is examined, revealing how the phase differences in the electronic and nuclear subspaces compensate for each other upon path closure. In this way, we unambiguously demonstrate the role of the geometric phase in the interference process and shed light on its persistence beyond the adiabatic approximation.

8426 Recurrence of Papillary Thyroid Carcinoma Despite Undetectable Levels of Thyroglobulin Measured by Both Immunoassay and LCMS

Abstract Disclosure: M.G. Hamilton: None. G. Patel: None. S. Teja Sathi: None. K. Win: None. P. Lekprasert: None. Serum thyroglobulin (Tg) levels are affected by the presence of anti-thyroglobulin antibodies (anti-Tg Abs) during surveillance of differentiated thyroid cancer (DTC). About 20% of patients have positive anti-Tg Abs post-thyroidectomy and laboratory investigations for DTC surveillance may lead to false negative results. Liquid chromatography-tandem mass spectrometry (LCMS) is superior to immunoassay in measuring Tg levels in patients with the presence of anti-Tg Abs. Mass spectrometry is the only currently available method that could eliminate the interference of anti-Tg Abs in the quantification of Tg but is not readily available. We present the case of a patient who had a recurrence of DTC despite persistently undetectable Tg levels using both immunoassay and LCMS methods. The patient is a 49-year-old female with a history of papillary thyroid cancer who underwent total thyroidectomy followed by adjuvant radio-ablation. She presented to our endocrinology office for routine follow up for her DTC. She reported subjective unknown weight loss over four months. Her physical exam was unremarkable with no palpable neck swelling or mass. Vital signs were within normal limits. She continued to have undetectable levels of Tg as measured by immunoassay, stable levels of anti-Tg Abs ranging from 19 IU/mL to 33 IU/mL, and negative findings on her thyroid ultrasound for the first four years post-op. When she presented to the office five years post-thyroidectomy her anti-Tg Ab level had increased to 114 IU/mL and subsequently to 137 IU/mL a few months later despite undetectable Tg levels on both immunoassay and LCMS. A thyroid ultrasound was completed due to rising anti-Tg Abs levels which showed a suspicious one cm mass at the right thyroid bed and suspicious bilateral cervical lymph nodes. Repeated FNA biopsy of the bilateral cervical lymph nodes confirmed follicular epithelium with nuclear inclusions and grooves, compatible with recurrent papillary thyroid carcinoma. This patient had a recurrence of her DTC despite undetectable Tg levels on both immunoassay and LCMS. Tg is an important aspect of surveillance post-treatment for all patients with DTC because its presence is a surrogate for the presence of thyroid tissue and therefore the recurrence of thyroid malignancy. Clinicians must have a high index of suspicion when monitoring a patient with a history of DTC and the presence of anti-Tg Abs because it interferes with the accurate measurement of Tg levels. A study conducted by Azmat et al. demonstrated that measuring Tg levels via LCMS has been found to eliminate the confounding effect of anti-Tg Abs with a sensitivity and specificity of 44.4% and 94.1% respectively. However, our case illustrates that even LCMS is not always reliable in such situations, and increasing levels of anti-Tg Abs should be an individual risk factor for suspecting recurrence of DTC. Presentation: 6/3/2024

Electrostatically Interacting Wannier Qubits in Curved Space

A derivation of a tight-binding model from Schrödinger formalism for various topologies of position-based semiconductor qubits is presented in the case of static and time-dependent electric fields. The simplistic tight-binding model enables the description of single-electron devices at a large integration scale. The case of two electrostatically Wannier qubits (also known as position-based qubits) in a Schrödinger model is presented with omission of spin degrees of freedom. The concept of programmable quantum matter can be implemented in the chain of coupled semiconductor quantum dots. Highly integrated and developed cryogenic CMOS nanostructures can be mapped to coupled quantum dots, the connectivity of which can be controlled by a voltage applied across the transistor gates as well as using an external magnetic field. Using the anti-correlation principle arising from the Coulomb repulsion interaction between electrons, one can implement classical and quantum inverters (Classical/Quantum Swap Gate) and many other logical gates. The anti-correlation will be weakened due to the fact that the quantumness of the physical process brings about the coexistence of correlation and anti-correlation at the same time. One of the central results presented in this work relies on the appearance of dissipation-like processes and effective potential renormalization building effective barriers in both semiconductors and in superconductors between not bended nanowire regions both in classical and in quantum regimes. The presence of non-straight wire regions is also expressed by the geometrical dissipative quantum Aharonov–Bohm effect in superconductors/semiconductors when one obtains a complex value vector potential-like field. The existence of a Coulomb interaction provides a base for the physical description of an electrostatic Q-Swap gate with any topology using open-loop nanowires, with programmable functionality. We observe strong localization of the wavepacket due to nanowire bending. Therefore, it is not always necessary to build a barrier between two nanowires to obtain two quantum dot systems. On the other hand, the results can be mapped to the problem of an electron in curved space, so they can be expressed with a programmable position-dependent metric embedded in Schrödinger’s equation. The semiconductor quantum dot system is capable of mimicking curved space, providing a bridge between fundamental and applied science in the implementation of single-electron devices.

Temporal Pound-Rebka experiment as gravitational Aharonov-Bohm effect

Temporal Pound-Rebka experiment as gravitational Aharonov-Bohm effect

Aharonov-Bohm effect mediated by massive photons

Virtual photons play an essential role in the locally realistic description of the Aharonov-Bohm interference. We show that the effect of virtual photons in the interferometer is manifested by a change in their spectrum. In particular, when a vacuum is confined between two ideal conducting plates, the photons obey the two-dimensional Proca equation, the wave equation with finite effective mass. This results in a short-range interaction between a test charge and a magnetic flux, and hence the Aharonov-Bohm effect is reduced exponentially at a large distance between the two bodies. On the other hand, a semiclassical description is also possible, and this raises the interesting question of how to prove the physical reality of virtual photons.

Sharpening the gravitational Aharonov–Bohm effect

We study the recent gravitational analogue of the Aharonov–Bohm effect for a classical system, namely a complex scalar field. We use this example to demonstrate that the Aharonov–Bohm effect in principle has nothing to do with quantum-mechanics. We then discuss how this classical field description can be connected to the standard one particle quantum description of the Aharonov–Bohm effect.

Scalar gravitational Aharonov–Bohm effect: Generalization of the gravitational redshift

The Aharonov–Bohm effect is a quantum mechanical phenomenon that demonstrates how potentials can have observable effects even when the classical fields associated with those potentials are absent. Initially proposed for electromagnetic interactions, this effect has been experimentally confirmed and extensively studied over the years. More recently, the effect has been observed in the context of gravitational interactions using atom interferometry. Additionally, recent predictions suggest that temporal variations in the phase of an electron wave function will induce modulation sidebands in the energy levels of an atomic clock, solely driven by a time-varying scalar gravitational potential. In this study, we consider the atomic clock as a two-level system undergoing continuous Rabi oscillations between the electron's ground and excited state. We assume the photons driving the transition are precisely frequency-stabilized to match the transition, enabling accurate clock comparisons. Our analysis takes into account, that when an atom transitions from its ground state to an excited state, it absorbs energy, increasing its mass according to the mass-energy equivalence principle. Due to the mass difference between the two energy levels, we predict that an atomic clock in an eccentric orbit experiencing a time-varying gravitational potential, will exhibit a constant frequency redshift relative to a ground clock, corresponding to the orbit's average gravitational redshift. Additionally, modulation sidebands will appear, and detecting these predicted sidebands would confirm the scalar gravitational Aharonov–Bohm effect.

A Non-Relativistic 2D Quantum System and Its Thermo-Magnetic Properties with a Generalized Pseudo-Harmonic Oscillator

In this work, we examine the thermo-magnetic characteristics and energy spectra of a system exposed to both magnetic and Aharonov–Bohm (AB) fields with the existence of an interaction potential that is pseudo-harmonic. Explicit calculations of the eigen-solutions are performed with the expanded Nikiforov–Uvarov formalism. The confluent Heun function is used to represent the equivalent wave functions. If the AB and magnetic fields are gone, quasi-degeneracy in the system’s energy levels is shown by a numerical analysis of the energy spectrum. Additionally, we provided a visual representation of how the AB and magnetic fields affected the system’s thermo-magnetic characteristics. Our results show a strong dependence of thermo-magnetic properties on temperature, screening parameters, external magnetic fields, and AB fields.

Intranasal LAG3 antibody infusion induces a rapid antidepressant effect via the hippocampal ERK1/2-BDNF signaling pathway in chronically stressed mice

The decline of microglia in the dentate gyrus is a new phenomenon that may explain the pathogenesis of depression, and reversing this decline has an antidepressant effect. The development of strategies that restore the function of dentate gyrus microglia in under stressful conditions is becoming a new focus. Lymphocyte-activating gene-3 (LAG3) is an immune checkpoint expressed by immune cells including microglia. One of its functions is to suppress the expansion of immune cells. In a recent study, chronic systemic administration of a LAG3 antibody that readily penetrates the brain was reported to reverse chronic stress-induced hippocampal microglia decline and depression-like behaviors. We showed here that a single intranasal infusion of a LAG3 antibody (In-LAG3 Ab) reversed chronic unpredictable stress (CUS)-induced depression-like behaviors in a dose-dependent manner, which was accompanied by an increase in brain-derived neurotrophic factor (BDNF) in the dentate gyrus. Infusion of an anti-BDNF antibody into the dentate gyrus, construction of knock-in mice with the BDNF Val68Met allele, or treatment with the BDNF receptor antagonist K252a abolished the antidepressant effect of In-LAG3 Ab. Activation of extracellular signal-regulated kinase1/2 (ERK1/2) is required for the reversal effect of In-LAG3 Ab on CUS-induced depression-like behaviors and BDNF decrease in the dentate gyrus. Moreover, both inhibition and depletion of microglia prevented the reversal effect of In-LAG3 Ab on CUS-induced depression-like behaviors and impairment of ERK1/2-BDNF signaling in the dentate gyrus. These results suggest that In-LAG3 Ab exhibits an antidepressant effect through microglia-mediated activation of ERK1/2 and synthesis of BDNF in the dentate gyrus.

Manifestation of the quantum metric in chiral lattice systems

Recent years have seen a surge in research on the role of quantum geometry in condensed matter physics. For instance, the Aharonov-Bohm effect is a physical phenomenon where the vector potential induces a phase shift of electron wavepackets in regions with zero magnetic fields due to an obstruction in space associated with a magnetic flux. A similar effect can be observed in solid-state systems, where the topology of the Berry connection can influence electron dynamics. These are paradigmatic examples of how the dynamics can be affected by the system’s geometry. Here, we show that in chiral-symmetric processes the quantum metric has a measurable effect on the mean chiral displacement of delocalized wavefunctions. This finding is supported by a photonic experiment realizing a topological quantum walk and demonstrates an effect that can be attributed directly to the geometry of the state space.

Targeting TNFRSF25 by agonistic antibodies and multimeric TL1A proteins co-stimulated CD8+ T cells and inhibited tumor growth

BackgroundTumor necrosis factor receptor superfamily 25 (TNFRSF25) is a T-cell co-stimulatory receptor. Expression of its ligand, TNF-like cytokine 1A (TL1A), on mouse tumor cells has been shown to promote tumor...

Rotating effects on the photoionization cross-section of a 2D quantum ring

In this article, we investigate the nonrelativistic quantum motion of a charged particle within a rotating frame, taking into account the Aharonov–Bohm (AB) effect and a uniform magnetic field. Our analysis entails the derivation of the equation of motion and the corresponding radial equation to describe the system. Solving the resulting radial equation enables us to determine the eigenvalues and eigenfunctions, providing a clear expression for the energy levels. Furthermore, our numerical analysis highlights the substantial influence of rotation on both energy levels and optical properties. Specifically, we evaluate the photoionization cross-section with and without the effects of rotation. To elucidate the impact of rotation on the photoionization process of the system, we present graphics that offer an appealing visualization of the intrinsic nature of the physics involved.

Approximate solutions for diatomic molecules under combined potentials in a global monopole and Aharonov–Bohm flux field

AbstractBound state energy eigensolutions of nine different diatomic molecules, specifically, , TiH, , CO, NO, ScH, CrH, HCl and LiH, placed in a point‐like global monopole, have been calculated by solving the time‐independent Schrödinger equation (SE). The molecules are confined by the Aharonov–Bohm (AB) flux field and the interaction potential among the charged particles is governed by the combined screened modified Kratzer potential (SMKP) plus Hulthén potential model. Three other special cases of the interaction potential have also been discussed here. Asymptotic iteration method has been used for the mathematical calculations. It is difficult to solve the SE exactly for any non‐zero values of the azimuthal quantum number due to the presence of the centrifugal barrier term. The well‐known Pekeris approximation technique for the terms and has taken into consideration for the purpose of performing numerical computations connected to an arbitrary state. The outcomes of this study are in reasonable agreement with the results of previous research on SMKP, Kratzer‐Fues potential, and modified Kratzer potential in the Minkowski space. It is observed that the energy spectra of the diatomic molecules suffer considerable change due to the effects of the background AB‐flux field and topological defect parameter.

Aharonov-Bohm experiments in magnetic field without the Landau levels

We discuss the two-slit experiment and the Aharonov-Bohm (AB) experiment in the magnetic field, where an electron produces so called synchrotron radiation. In other words, the photons are emitted from the points of the electron trajectory and it means that the trajectory of electron is visible in the synchrotron radiation spectrum. The axiomatic system of quantum mechanics does not enable to define the trajectory of the elementary particle. The two-slit experiment and the AB experiment in magnetic field are the missing experiments of quantum mechanics. The extension of the discussion to the cosmical rays moving in the magnetic field of the Saturn magnetosphere and its rings is mentioned. It is related to the probe CASSINI.

Aharonov–Bohm Effect as a Diffusion Phenomenon

Aharonov–Bohm Effect as a Diffusion Phenomenon

Breast Milk-Derived Antibodies Impair Vaccine Immunity in Suckling Mice.

Breast milk confers multiple benefits to the neonate, including passive immunity against multiple microorganisms via Abs. However, it remains unclear whether breast milk-derived Abs affect vaccine-induced immunity in the neonate. We evaluated in C57BL/6 and BALB/c mice whether breastfeeding from an mRNA-SARS-CoV-2-vaccinated dam affects vaccine-induced immunity in neonate mice. Using an experimental model that allows the distinction of maternal Abs and neonate Abs based on their allotype, we show that breastfeeding from an immune dam is associated with reduced vaccine immunity in the neonate. Importantly, mice that breastfed from an immune dam showed reduced numbers of plasma cells after vaccination, relative to mice that breastfed from a naive dam. Our subsequent studies using an mRNA-luciferase reporter system show that passive transfer of Abs through breastfeeding accelerates the clearance of vaccine Ag in suckling mice, resulting in reduced Ag availability. Altogether, maternal Abs transferred through breast milk can protect against infectious microorganisms, but they may also interfere with the neonate's response to vaccination by accelerating the clearance of vaccine Ag. These findings are important for understanding the effects of maternal Abs on the neonate's response to vaccines and may provide insights for improving neonatal vaccines.

Anti-CRMP2 antibody induces anxiety-like behavior and increases pyramidal neuron excitability in mice

BackgroundWe have previously identified auto-antibody (Ab) to collapsin response mediator protein 2 (CRMP2) in patients with encephalitis. The present study aims to evaluate the pathogenic effects of anti-CRMP2 Ab. MethodsRecombinant CRMP2 protein was injected subcutaneously into mice to establish an active immune mouse model with anti-CRMP2 Ab. Behavioral assessments, histopathological staining, and electrophysiological testing were performed to identify any pathogenic changes. ResultsThe mice exhibited signs of impaired motor coordination four weeks post-immunization of CRMP2 protein. Moreover, CRMP2 immunized mice for eight weeks showed anxiety-like behaviors indicating by tests of open field and the elevated plus maze. After incubating the CA1 region of hippocampal brain section with the sera from CRMP2 immunized mice, the whole-cell path-clamp recordings showed increased excitability of pyramidal neurons. However, no obvious inflammation and infiltration of immune cells were observed by histopathological analysis. Western blot showed that the phosphorylation levels of CRMP2-Thr514 and -Ser522 were not affected. ConclusionIn an active immunization model with CRMP2 protein, impaired coordination and anxiety-like behaviors were observed. Also, anti-CRMP2 Abs containing sera heightened the excitability of hippocampal pyramidal neurons in vitro, which imply the pathogenic effects of anti-CRMP2 Ab.

Aharonov-Bohm effect in Generalized Electrodynamics

The Aharonov-Bohm (AB) effect is considered in the context of Generalized Electrodynamics (GE) by Podolsky and Bopp. GE is the only extension to Maxwell electrodynamics that is locally U(1)-gauge invariant, admits linear field equations and contains higher-order derivatives of the vector potential. GE admits both massless and massive modes for the photon. We recover the ordinary quantum phase shift of the AB effect, derived in the context of Maxwell electrodynamics, for the massless mode of the photon in GE. The massive mode induces a correction factor to the AB phase shift depending on the photon mass. We study both the magnetic AB effect and its electric counterpart. In principle, accurate experimental observations of AB the phase shift could be used to constrain GE photon mass.