The Response of Black Hole Spark Gaps to External Changes: A Production Mechanism of Rapid TeV Flares?

We study the response of a starved Kerr black hole magnetosphere to abrupt changes in the intensity of disk emission and in the global magnetospheric current, by means of one-dimensional general relativistic particle-in-cell simulations. Such changes likely arise from the intermittency of the accretion process. We find that in cases where the pair-production opacity contributed by the soft disk photons is modest, as in, e.g., M87, such changes can give rise to delayed, strong teraelectronvolt (TeV) flares, dominated by curvature emission of particles accelerated in the gap. The flare rise time, and the delay between the external variation and the onset of the flare emitted from the outer gap boundary, are of the order of the light-crossing time of the gap. The rapid, large-amplitude TeV flares observed in M87, and perhaps, other active galactic nuclei may be produced by such a mechanism.

Correlations in twisted double-layer graphene with virtual photons in a microcavity

We analyze the entanglement generation of a system composed of two decoupled rotated graphene layers inside a planar microcavity. By considering the electromagnetic field of the cavity in the vacuum state and using time-dependent perturbation theory it is possible to obtain the range of geometric parameters at which the quantum states of electrons in different layers are entangled. By employing the negativity measure, correlations between layers are obtained for time scales smaller than the light-crossing time of the layers. It is shown that the negativity measure is modulated by the rotation angle between layers, allowing manipulation of X states. Finally, an experimental protocol is analyzed in order to detect non-causal effects between layers, by allowing back-voltage switching functions in the two layers with supports that do not overlap in time. By turning off the second-back voltage at a time smaller than the light-crossing time, it is possible to obtain correlations between layers through the independent interaction with virtual photons. The exchange of virtual photons implies that the propagator can be nonzero outside the light cone and this non-causal propagation can create entangled quantum states.

EXAMPLE OF APPLICATION OF THE PONTRYAGIN’S MINIMUM PRINCIPLE “PMP EXTENSION”: ZERMELO PROBLEM (WITH CURRENT SPEED MORE THAN BOAT SPEED HYPOTHESIS)

We present an example of application covering several cases using the extension of the Pontryaguine minimum principle (PMP) in the case where we add a constraint on reaching a target variety at the final time: the Zermelo problem with current speed more than Boat speed hypothesis, where we consider a boat crossing a channel under a strong current and where we try to reach the opposite bank by minimizing the lateral offset or by minimizing the crossing time.

An analysis of manual and autoanalysis for submicrosecond parameters in the typical first lightning return stroke

The mechanism on how lightning detection system (LDS) operated never been exposed by manufacturer since it was confidential. This scenario motivated the authors to explore the issue above by using MATLAB to develop autoanalysis software based on the feature extraction. This extraction is intended for recognizing the parameters in the first return stroke, and compare the measurement between the autoanalysis software and the manual analysis. This paper is a modification based on a previous work regarding autoanalysis of zero-crossing time and initial peak of return stroke using features extraction programming technique. Further, the parameter on rising time of initial peak is added in this autoanalysis programming technique. Finally, the manual analysis using WaveStudio (LeCroy product) of those two lightning parameters is compared with autoanalysis software. This study found that the autoanalysis produce similar result with the manual analysis, hence proved the reliability of this software.

Efektivitas Waktu Persilangan Tiga Genotipe Cabai (Capcicum sp) pada Persilangan Dialel

Chili is an important horticultural commodity in Indonesia. However, its production is still not optimal because there are not many superior seeds available, which causes low productivity. One solution to this problem is to improve planting material (seeds) by a plant breeding program through a hybridization process. Crossing different types of chili requires the right time to increase the chances of success. The purpose of this study was to determine the effectiveness of crossing three genotypes of chili (two introduced and one local). The study was carried out with a factorial randomized design. The first factor was a combination of crosses of three parents, namely Sweet Italian, Garda and Katokkon by dialel crosses. The second factor was the time of crossing, namely at 04.00, 05.00, 06.00, 07.00, 08.00. The results of the analysis showed that the combination of parents had an interaction with crossing time in increasing the dsuccess of the crosses. Each parent combination hah a specific time for crossing. If the female parent was Sweet Italian, the time of crossing early in the morning (low temperature) was more optimal, which was between 04.00-07.00. For Katokkon×Garda crosses and their reciprocals, the percentage of successful crosses increased if it was done at 06.00-08.00. None of the crosses between Garda×Sweet Italian were successful or were entirely lethal. Keywords: chili, crossing time, dialele , introduction genotype ABSTRAK Cabai merupakan komoditas hortikultura yang penting di Indonesia. Namun produksinya masih belum optimal karena belum banyak tersedia benih unggul, yang menyebabkan rendahnya produktivitas. Salah satu solusi masalah tersebut adalah dengan perbaikan bahan tanam (benih) melalui program pemuliaan tanaman dengan proses persilangan (hibridisasi). Persilangan cabai yang berbeda jenis memerlukan waktu yang tepat untuk dapat meningkatkan peluang keberhasilannya. Tujuan penelitian ini adalah untuk mengetahui efektivitas waktu persilangan tiga genotipe cabai (dua introduksi dan satu lokal). Penelitian dilaksanakan dengan rancangan acak kelompok faktorial, Faktor pertama adalah kombinasi persilangan dari tiga tetua, yaitu Sweet Italian, Garda dan Katokkon secara dialel. Faktor kedua adalah waktu persilangan, yaitu pada pukul 04.00, 05.00, 06.00, 07.00, 08.00. Hasil analisis menunjukkan bahwa kombinasi tetua memiliki interaksi dengan waktu persilangan dalam meningkatkan keberhasilan persilangan. Tiap kombinasi tetua memiliki waktu yang spesifik untuk persilangan. Jika tetua betina Sweet Italian, waktu persilangannya semakin pagi (suhu rendah) semakin optimal, yakni di antara pukul 04.00-07.00. Untuk persilangan Katokkon×Garda maupun resiproknya, persentase keberhasilan persilangan semakin meningkat jika dilakukan pada pukul 06.00-08.00. Tidak ada penyerbukan silang antara Garda×Sweet Italian yang berhasil persilangan atau seluruhnya letal. Kata kunci: cabai, dialel , genotipe introduksi, waktu persilangan