Magnonic superradiant phase transition

In the superradiant phase transition (SRPT), coherent light and matter fields are expected to appear spontaneously in a coupled light–matter system in thermal equilibrium. However, such an equilibrium SRPT is forbidden in the case of charge-based light–matter coupling, known as no-go theorems. Here, we show that the low-temperature phase transition of ErFeO3 at a critical temperature of approximately 4 K is an equilibrium SRPT achieved through coupling between Fe3+ magnons and Er3+ spins. By verifying the efficacy of our spin model using realistic parameters evaluated via terahertz magnetospectroscopy and magnetization experiments, we demonstrate that the cooperative, ultrastrong magnon–spin coupling causes the phase transition. In contrast to prior studies on laser-driven non-equilibrium SRPTs in atomic systems, the magnonic SRPT in ErFeO3 occurs in thermal equilibrium in accordance with the originally envisioned SRPT, thereby yielding a unique ground state of a hybrid system in the ultrastrong coupling regime.

Case Report of Typhoid Fever (Salmonella typhi)

Typhoid fever is a major health problem globally. Typhoid fever is an enteric fever characterized by systemic illness along with abdominal pain and fever in a "step-ladder" pattern. Typhoid fever is one of the major causes of mortality and morbidity in overcrowded and unhygienic areas though comprehensive research and public health interventions have decreased the occurrence. Patient is having sign symptoms as gastrointestinal symptoms, malaise, hepatomegaly, and high liver enzymes presented with a two-week fever. As a differential diagnosis, a Widal test is done and two blood cultures were requested; both came out positive, confirming the diagnosis of typhoid fever caused by Salmonella typhi. Treatment with ceftriaxone and metronidazole was stared prior to confirmation of the diagnosis, with a partial response; later, pharmacological therapy was altered based on ciprofloxacin susceptibility testing, with a satisfactory clinical response. We look at how to diagnose and treat enteric fever, with an importance to typhoid fever. Symptoms or important clinical finding:- A 6 year old male was admitted in A.V.B.R.H on date 12/03/2021 with chief complaint of abdominal discomfort, malaise, problems such as fever since 2 weeks, gastrointestinal symptoms, lethargy, hepatomegaly, and an increased liver enzyme. Diagnosis therapeutic intervention and outcome: A case is diagnosed as Typhoid Fever. After physical examination and investigation, doctor was detected a case of 6 week. Therapeutic intervention and outcome: Also provide a calcium supplements and iron supplements present case was stable but according to ultrasonography finding. Outcome- Good sanitation, improved water supply, and a suitable sewage waste matter system, as well as the successful use of existing typhoid vaccinations, can all help to avoid typhoid fever. Nursing Perspective: Administration fluid replacement .i.e DNS and RL monitored vital signs per hourly. Maintained temperature chart 2 hourly strictly, maintained intake output chart properly. Tablet paracetamol, antibiotics given as per doctor’s order. Conclusion: Good sanitation, improved water supply, and a suitable sewage waste matter system, as well as the successful use of existing typhoid vaccinations, can all help to avoid typhoid fever.

Detecting scale anomaly in chiral phase transition of QCD: new critical endpoint pinned down

Violation of scale symmetry, scale anomaly, being a radical concept in quantum field theory, is of importance to comprehend the vacuum structure of QCD, and should potentially contribute to the chiral phase transition in thermal QCD, as well as the chiral and U(1) axial symmetry. Though it should be essential, direct evidence of scale anomalies has never been observed in the chiral phase transition. We propose a methodology to detect a scale anomaly in the chiral phase transition, which is an electromagnetically induced scale anomaly: apply a weak magnetic field background onto two-flavor massless QCD with an extremely heavy strange quark, first observe the chiral crossover; second, adjusting the strange quark mass to be smaller and smaller, observe the second-order chiral phase transition, and then the first-order one in the massless-three flavor limit. Thus, the second-order chiral phase transition, observed as the evidence of the quantum scale anomaly, is a new critical endpoint. It turns out that this electromagnetic scale anomaly gets most operative in the weak magnetic field regime, rather than a strong field region. We also briefly address accessibility of lattice QCD, a prospected application to dense matter system, and implications to astrophysical observations, such as gravitational wave productions provided from thermomagnetic QCD-like theories.

Semi-classical thermodynamics of quantum extremal surfaces in Jackiw-Teitelboim gravity

Quantum extremal surfaces (QES), codimension-2 spacelike regions which extremize the generalized entropy of a gravity-matter system, play a key role in the study of the black hole information problem. The thermodynamics of QESs, however, has been largely unexplored, as a proper interpretation requires a detailed understanding of backreaction due to quantum fields. We investigate this problem in semi-classical Jackiw-Teitelboim (JT) gravity, where the spacetime is the eternal two-dimensional Anti-de Sitter (AdS2) black hole, Hawking radiation is described by a conformal field theory with central charge c, and backreaction effects may be analyzed exactly. We show the Wald entropy of the semi-classical JT theory entirely encapsulates the generalized entropy — including time-dependent von Neumann entropy contributions — whose extremization leads to a QES lying just outside of the black hole horizon. Consequently, the QES defines a Rindler wedge nested inside the enveloping black hole. We use covariant phase space techniques on a time-reflection symmetric slice to derive a Smarr relation and first law of nested Rindler wedge thermodynamics, regularized using local counterterms, and intrinsically including semi-classical effects. Moreover, in the microcanonical ensemble the semi-classical first law implies the generalized entropy of the QES is stationary at fixed energy. Thus, the thermodynamics of the nested Rindler wedge is equivalent to the thermodynamics of the QES in the microcanonical ensemble.

Existence of Steady States of the Massless Einstein–Vlasov System Surrounding a Schwarzschild Black Hole

We show that there exist steady states of the spherically symmetric massless Einstein–Vlasov system which surround a Schwarzschild black hole. The steady states are (thick) shells with finite mass and compact support. Furthermore we prove that an arbitrary number of shells, necessarily well separated, can surround the black hole. To our knowledge this is the first result of static self-gravitating solutions to any massless Einstein-matter system which surround a black hole. We also include a numerical investigation about the properties of the shells.

Conditions for metachronal coordination in arrays of model cilia

On surfaces with many motile cilia, beats of the individual cilia coordinate to form metachronal waves. We present a theoretical framework that connects the dynamics of an individual cilium to the collective dynamics of a ciliary carpet via systematic coarse graining. We uncover the criteria that control the selection of frequency and wave vector of stable metachronal waves of the cilia and examine how they depend on the geometric and dynamical characteristics of a single cilium, as well as the geometric properties of the array. We perform agent-based numerical simulations of arrays of cilia with hydrodynamic interactions and find quantitative agreement with the predictions of the analytical framework. Our work sheds light on the question of how the collective properties of beating cilia can be determined using information about the individual units and, as such, exemplifies a bottom-up study of a rich active matter system.