Microcausality of spin-induced noncommutative theories

In this brief report, the microcausility of quantum field theory on spin-induced noncom- mutative spacetime is discussed. It is found that for spacelike seperation the microcausality is not obeyed by the theory generally. It means that Lorentz covariance can not guaran- tee microcausality in quantum field thoery. We also give some comments about quantum field thoeries on such noncommutative spacetime and the relations between noncommutative spacetime and causality.Comment: 9 pages, no figur

TeV Scale Phenomenology of e+e−→μ+μ−e^+e^- \to\mu^+ \mu^- Scattering in the Noncommutative Standard Model with Hybrid Gauge Transformation

The hybrid gauge transformation and its nontrivial phenomenological implications are investigated using the noncommutative gauge theory with the Seiberg-Witten map expanded scenario. Particularly, the $e^+e^- \to\mu^+ \mu^-$ process is studied with a generalized noncommutative standard model (NCSM) including massive neutrinos and neutrino-photon interaction. In this model, the hybrid gauge transformation in the lepton sector is naturally introduced through the requirement of gauge invariance of the seesaw neutrino mass term. It is shown that in the NCSM without hybrid gauge transformation the noncommutative correction to the scattering amplitude of the $e^+e^- \to\mu^+ \mu^-$ process appears only as a phase factor, predicting no new physical deviation in the cross section. However, when the hybrid feature is considered, the noncommutative effect appears in the single channel process. The cross section and angular distribution are analyzed in the laboratory frame including Earth's rotation. It is proposed that pair production of muons in the upcoming TeV International Linear Collider (ILC) can provide an ideal opportunity for exploring not only the NC space-time, but also the mathematical structure of the corresponding gauge theory.Comment: 22 pages, 8 figure

Multigluon tree amplitudes with a pair of massive fermions

We consider the calculation of n-point multigluon tree amplitudes with a pair of massive fermions in QCD. We give the explicit transformation rules of this kind of massive fermion-pair amplitudes with respect to different reference momenta and check the correctness of them by SUSY Ward identities. Using these rules and onshell BCFW recursion relation, we calculate the analytic results of several n-point multigluon amplitudes.Comment: 15page

Moderating Role of Creative Mindset in the Effect of Metacognitive Experience on Insight Problem Solving

Metacognitive experience, measured by processing fluency, contributes to divergent thinking performance; however, whether it exhibits varying effects on insight problem-solving remains unknown. Additionally, as individuals’ interpretation of metacognitive experience is influenced by their creative mindset, whether creative mindset plays a role in the relationship between metacognitive experience and insight problem-solving is another issue. In Experiment 1, a Chinese logogriph task was used to investigate insight problem-solving performance. The font style of logogriphs (easy versus difficult) was used to alter the ease of processing. The results showed that individuals had lower performance accuracy for logogriphs presented in difficult font styles, suggesting the negative effect of metacognitive disfluency experience on logogriph solving. In Experiment 2, different creative mindsets (entity versus incremental) were activated in individuals via prime manipulation. Individuals with an incremental creative mindset had a significantly higher performance accuracy and longer reaction time for logogriphs presented in difficult font styles than individuals with an entity creative mindset, suggesting that an incremental creative mindset might counteract the negative effect of metacognitive disfluency experience on logogriphs solving. These findings suggest that metacognitive disfluency experience has a negative effect on insight problem-solving and that a creative mindset moderated this effect

Position Estimation Method for Unmanned Tracked Vehicles Based on a Steering Dynamics Model

A position estimation method for unmanned tracked vehicles based on a steering dynamics model was developed during this study. This method can be used to estimate the position of a tracked vehicle in real time without relying on a high-precision positioning system. First, the relationship between the shear displacement of the track relative to the ground and the speed and yaw rate of the tracked vehicle during the steering process was analyzed. Next, the steering force of the tracked vehicle was calculated by using the shear force–displacement theory, and a steering dynamics model considering the acceleration of the vehicle was established. The experimental results show that this steering dynamics model produced more accurate position estimations for an unmanned tracked vehicle than did the kinematics model. This method can serve as a reference for the positioning of unmanned tracked vehicles working in special environments that cannot use precise positioning systems