Scattering amplitudes for all masses and spins Arkani-Hamed, Nima; Huang, Tzu-Chen; Huang, Yu-tin
The journal of high energy physics,
11/2021, Letnik:
2021, Številka:
11
Journal Article
Recenzirano
Odprti dostop
A
bstract
We introduce a formalism for describing four-dimensional scattering amplitudes for particles of any mass and spin. This naturally extends the familiar spinor-helicity formalism for massless ...particles to one where these variables carry an extra
SU
(2) little group index for massive particles, with the amplitudes for spin
S
particles transforming as symmetric rank 2
S
tensors. We systematically characterise all possible three particle amplitudes compatible with Poincare symmetry. Unitarity, in the form of consistent factorization, imposes algebraic conditions that can be used to construct all possible four-particle tree amplitudes. This also gives us a convenient basis in which to expand all possible four-particle amplitudes in terms of what can be called “spinning polynomials”. Many general results of quantum field theory follow the analysis of four-particle scattering, ranging from the set of all possible consistent theories for massless particles, to spin-statistics, and the Weinberg-Witten theorem. We also find a transparent understanding for why massive particles of sufficiently high spin cannot be “elementary”. The Higgs and Super-Higgs mechanisms are naturally discovered as an infrared unification of many disparate helicity amplitudes into a smaller number of massive amplitudes, with a simple understanding for why this can’t be extended to Higgsing for gravitons. We illustrate a number of applications of the formalism at one-loop, giving few-line computations of the electron (
g −
2) as well as the beta function and rational terms in QCD. “Off-shell” observables like correlation functions and form-factors can be thought of as scattering amplitudes with external “probe” particles of general mass and spin, so all these objects — amplitudes, form factors and correlators, can be studied from a common on-shell perspective.
The EFT-hedron Arkani-Hamed, Nima; Huang, Tzu-Chen; Huang, Yu-tin
The journal of high energy physics,
05/2021, Letnik:
2021, Številka:
5
Journal Article
Recenzirano
Odprti dostop
A
bstract
We re-examine the constraints imposed by causality and unitarity on the low-energy effective field theory expansion of four-particle scattering amplitudes, exposing a hidden “totally ...positive” structure strikingly similar to the positive geometries associated with grassmannians and amplituhedra. This forces the infinite tower of higher-dimension operators to lie inside a new geometry we call the “EFT-hedron”. We initiate a systematic investigation of the boundary structure of the EFT-hedron, giving infinitely many linear and non-linear inequalities that must be satisfied by the EFT expansion in any theory. We illustrate the EFT-hedron geometry and constraints in a wide variety of examples, including new consistency conditions on the scattering amplitudes of photons and gravitons in the real world.
A
bstract
We consider the symmetry resolution of relative entropies in the 1+1 dimensional free massless compact boson conformal field theory (CFT) which presents an internal U(1) symmetry. We ...calculate various symmetry resolved Rényi relative entropies between one interval reduced density matrices of CFT primary states using the replica method. By taking the replica limit, the symmetry resolved relative entropy can be obtained. We also take the XX spin chain model as a concrete lattice realization of this CFT to perform numerical computation. The CFT predictions are tested against exact numerical calculations finding perfect agreement.
Our recent report illustrated the unitedly advantageous effects of postbiotic butyrate on active vitamin D3 (VD3)-orchestrated innate immunity in
colitis. There is growing awareness that aryl ...hydrocarbon receptor (AhR) can regulate intestinal immunity and barrier function, through modulating cecal inflammation and junction proteins expression. Hence, we researched the participation of AhR-regulated tight junction functions on the united effects of butyrate and VD3 on intestinal defense to
infection.
colitis model were elicited by oral gavage with 1 × 10
CFU of a
wild-type strain SL1344 in C57BL/6 mice. Before and after the colitis generation, mice were fed with butyrate and/or VD3 by oral gavage in the absence or presence of intraperitoneal injection of AhR inhibitor for 4 and 7 days, respectively. We observed that butyrate and VD3 could concert together to reduce the invasion of
in colitis mice by enhancing cecal cytokines and antimicrobial peptides expression and reducing zonulin and claudin-2 protein expressions in mucosal stain, compared to single treatment, which were counteracted by AhR inhibitor. It implies that AhR is involved in the united effects of butyrate and VD3 on the intestinal defense to
infection in colitis mice. This study discloses the promising alternative therapy of combining postbiotic and VD3 for invasive
and the pivotal role of AhR pathway.
The continued threat of emerging, highly lethal infectious pathogens such as Middle East respiratory syndrome coronavirus (MERS‐CoV) calls for the development of novel vaccine technology that offers ...safe and effective prophylactic measures. Here, a novel nanoparticle vaccine is developed to deliver subunit viral antigens and STING agonists in a virus‐like fashion. STING agonists are first encapsulated into capsid‐like hollow polymeric nanoparticles, which show multiple favorable attributes, including a pH‐responsive release profile, prominent local immune activation, and reduced systemic reactogenicity. Upon subsequent antigen conjugation, the nanoparticles carry morphological semblance to native virions and facilitate codelivery of antigens and STING agonists to draining lymph nodes and immune cells for immune potentiation. Nanoparticle vaccine effectiveness is supported by the elicitation of potent neutralization antibody and antigen‐specific T cell responses in mice immunized with a MERS‐CoV nanoparticle vaccine candidate. Using a MERS‐CoV‐permissive transgenic mouse model, it is shown that mice immunized with this nanoparticle‐based MERS‐CoV vaccine are protected against a lethal challenge of MERS‐CoV without triggering undesirable eosinophilic immunopathology. Together, the biocompatible hollow nanoparticle described herein provides an excellent strategy for delivering both subunit vaccine candidates and novel adjuvants, enabling accelerated development of effective and safe vaccines against emerging viral pathogens.
To improve vaccination efforts against Middle East respiratory syndrome coronavirus (MERS‐CoV), a virus‐mimicking vaccine is herein prepared with a capsid‐like hollow polymeric nanoparticle loaded with STING agonists and coated in MERS‐CoV antigens. The viromimetic nanoparticle facilitates safe and effective vaccination against the lethal virus and offers a versatile platform for combatting emerging infectious threats.
Although many techniques exist to transfer data from the widely distributed sensors that make up the Internet of Things (IoT) (e.g., using 3G/4G networks or cables), these methods are associated with ...prohibitively high costs, making them impractical for real-life applications. Recently, several emerging wireless technologies have been proposed to provide long-range communication for IoT sensors. Among these, LoRa has been examined for long-range performance. Although LoRa shows good performance for long-range transmission in the countryside, its radio signals can be attenuated over distance, and buildings, trees, and other radio signal sources may interfere with the signals. Our observations show that in urban areas, LoRa requires dense deployment of LoRa gateways (GWs) to ensure that indoor LoRa devices can successfully transfer data back to remote GWs. Wireless mesh networking is a solution for increasing communication range and packet delivery ratio (PDR) without the need to install additional GWs. This paper presents a LoRa mesh networking system for large-area monitoring of IoT applications. We deployed 19 LoRa mesh networking devices over an <inline-formula> <tex-math notation="LaTeX">800\,\,\text {m} \times 600 </tex-math></inline-formula> m area on our university campus and installed a GW that collected data at 1-min intervals. The proposed LoRa mesh networking system achieved an average 88.49% PDR, whereas the star-network topology used by LoRa achieved only 58.7% under the same settings. To the best of our knowledge, this is the first academic study discussing LoRa mesh networking in detail and evaluating its performance via real experiments.
A
bstract
In this paper, we consider the time evolution of charge imbalance resolved negativity after a global quench in the 1+1 dimensional complex Klein-Gordon theory. We focus on two types of ...global quenches which are called boundary state quench and mass quench respectively. We first study the boundary state quench where the post-quench dynamic is governed by a massless Hamiltonian. In this case, the temporal evolution of charged imbalance resolved negativity can be obtained first by evaluating the correlators of the fluxed twist field in the upper half plane and then applying Fourier transformation. We test our analytical formulas in the underlying lattice model numerically. We also study the mass quench in the complex harmonic chain where the system evolves according to a massive Hamiltonian after the quench. We argue that our results can be understood in the framework of quasi-particle picture.
A
bstract
We construct the defining data of two-dimensional topological field theories (TFTs) enriched by non-invertible symmetries/topological defect lines. Simple formulae for the three-point ...functions and the lasso two-point functions are derived, and crossing symmetry is proven. The key ingredients are open-to-closed maps and a boundary crossing relation, by which we show that a diagonal basis exists in the defect Hilbert spaces. We then introduce regular TFTs, provide their explicit constructions for the Fibonacci, Ising and Haagerup ℋ
3
fusion categories, and match our formulae with previous bootstrap results. We end by explaining how non-regular TFTs are obtained from regular TFTs via generalized gauging.
Little is known about the composition and clinical implications of lung microbiome in patients with chronic obstructive pulmonary disease (COPD) and community-acquired pneumonia requiring invasive ...mechanical ventilation and intensive care unit admission. Therefore, this study aimed to explore the longitudinal changes in microbial airway composition and its variations between COPD patients with different weaning outcomes. Fifty-one endotracheal aspirate samples from 21 participants and 5 saline samples were collected as the patient and control group, respectively. Sequence analysis revealed significant increases and upward trends in the relative abundance of the Acinetobacter genus and Acinetobacter baumannii complex species in paired comparisons of sampling points and over time, respectively, in patients with failed weaning (p for trend = 0.012 and 0.012, respectively) but not in those with successful weaning (p for trend = 0.335 and 0.426, respectively). Furthermore, significant changes in the composition of the bacterial community were observed in paired comparisons of sampling points in patients with failed weaning compared with those with successful weaning. The alpha diversity did not differ between the patients with different weaning outcomes. These results further the understanding of longitudinal airway microbiome structure analysis and its clinical implications when managing critically ill patients with and without COPD.
Introduction
Salmonella spp. pose major public health problems worldwide. A better understanding of the pathogenesis of these foodborne pathogens is a prerequisite for the design of improved ...intervention strategies that could reduce the use of antimicrobial agents and drug‐resistant Salmonellosis. Accumulating evidence indicates that vitamin D is involved in regulating innate immunity, and may, therefore, play a key role in human responses to infection. Studies have suggested 1,25‐dihydroxyvitamin D3 (1,25D3), the active form of vitamin D, effectively ameliorates colitis. These findings have broad implications for the use of vitamin D compounds in colitis. This study investigated the effect of active vitamin D3 on the severity of Salmonella colitis.
Methods
A Salmonella colitis model was established with 6–8‐week‐old male C57BL/6 mice: Streptomycin‐pretreated C57BL/6 mice were infected orally with Salmonella enterica serova Typhimurium wild‐type strain SL1344 for 48 h. The mice were randomly assigned to control, model, and 1,25(OH)2D3‐treated groups. After the experiment, the mice were sacrificed, and intestinal, spleen, and liver tissue samples were removed to analyze bacterial colonization, western blot for protein levels, and real‐time‐polymer chain reaction for messenger RNA (mRNA) expression.
Results
We observed that 1,25D3 reduced the severity of Salmonella colitis in C57BL/6 mice by reducing cecal mIL‐1beta, mIL‐6, mTNF‐alpha, and mIL‐8 mRNA expressions, bacterial colonization (CFU/mg tissue) in the liver and spleen, but increased the human β‐defensin‐2 mRNA and autophagy protein expression, compared to those of the SL1344 infection only.
Conclusions
Our results document that active vitamin D3 reduced Salmonella colitis by decreasing inflammation, and bacterial translocation via induction of killing and autophagic clearance of pathogenic organisms.
Our results suggest that active vitamin D3 reduced Salmonella colitis by decreasing inflammation and bacterial translocation via induction of killing and autophagic clearance of the pathogenic organism.
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