How generic are null spacetime singularities?

The spacetime singularities inside realistic black holes are sometimes thought to be spacelike and strong, since there is a generic class of solutions (BKL) to Einsteins equations with these properties. We show that null, weak singularities are also generic, in the following sense: there is a class of vacuum solutions containing null, weak singularities, depending on 8 arbitrary (up to some inequalities) analytic initial functions of 3 spatial coordinates. Since 8 arbitrary functions are needed (in the gauge used here) to span the generic solution, this class can be regarded as generic

Opini Mahasiswa terhadap Pelaksanaan Kuliah Kerja Nyata (Kukerta) di Universitas Riau

Field Work Experience (Kukerta) is intrakurikuler program with the main objective to provide education to students. The students of Field Work Experience (Kukerta) as a study conducted in the midst of the scientific community to implement possessed by every student of various disciplines, can then be applied in the middle of society. One of the institutions that implement activities Field Work Experience (Kukerta) is the University of Riau. The results showed that the students opinions is different, some refuse and support the implementation of Kukerta. The students opinions have mutual balance between supporting and rejecting.Key word : Communication, Opinion, Field Work Experience (Kukerta

Analisis Kepuasan Kerja Karyawan pada Hotel Sri Indrayani Pekanbaru

The purpose of this research is to know how the satisfaction of employees work in Sri Indrayani and how to improve the satisfaction of employees work in Sri Indrayani Hotel.This research is used descriptive quantitative methods. There were 30 sample all employee. The data collection techniques in this research used observation, interview, and quesionnaires. The likert scale was used to measure the intervals in quantitative data.This research theory used Harold E. Burt in the book of Pandji Anoraga (2005:82) theory. This theory divides job satisfaction into 3 categories: factor relationship between employees, individual factors, external factors.The analysis result of the employees work satisfaction is quite good in Sri Indrayani Hotel Pekanbaru. It is proved that the managemen of Sri Indrayani Hotel Pekanbaru have improved their employees work satisfaction maximally. As know in improving the employees work of satisfaction in Sri Indrayani Hotel Pekanbaru with challenged work mentally, good appreciation, good condition of work and supportive relationship.Keywords: promotion and promotion mix

Numerical investigation of black hole interiors

Gravitational perturbations which are present in any realistic stellar collapse to a black hole, die off in the exterior of the hole, but experience an infinite blueshift in the interior. This is believed to lead to a slowly contracting lightlike scalar curvature singularity, characterized by a divergence of the hole's (quasi-local) mass function along the inner horizon. The region near the inner horizon is described to great accuracy by a plane wave spacetime. While Einstein's equations for this metric are still too complicated to be solved in closed form it is relatively simple to integrate them numerically. We find for generic regular initial data the predicted mass inflation type null singularity, rather than a spacelike singularity. It thus seems that mass inflation indeed represents a generic self-consistent picture of the black hole interior.Comment: 6 pages LaTeX, 3 eps figure

The late-time singularity inside non-spherical black holes

It was long believed that the singularity inside a realistic, rotating black hole must be spacelike. However, studies of the internal geometry of black holes indicate a more complicated structure is typical. While it seems likely that an observer falling into a black hole with the collapsing star encounters a crushing spacelike singularity, an observer falling in at late times generally reaches a null singularity which is vastly different in character to the standard Belinsky, Khalatnikov and Lifschitz (BKL) spacelike singularity. In the spirit of the classic work of BKL we present an asymptotic analysis of the null singularity inside a realistic black hole. Motivated by current understanding of spherical models, we argue that the Einstein equations reduce to a simple form in the neighborhood of the null singularity. The main results arising from this approach are demonstrated using an almost plane symmetric model. The analysis shows that the null singularity results from the blueshift of the late-time gravitational wave tail; the amplitude of these gravitational waves is taken to decay as an inverse power of advanced time as suggested by perturbation theory. The divergence of the Weyl curvature at the null singularity is dominated by the propagating modes of the gravitational field. The null singularity is weak in the sense that tidal distortion remains bounded along timelike geodesics crossing the Cauchy horizon. These results are in agreement with previous analyses of black hole interiors. We briefly discuss some outstanding problems which must be resolved before the picture of the generic black hole interior is complete.Comment: 16 pages, RevTeX, 3 figures included using psfi

Penilaian Ekonomi Sampah Kertas Di Kota Medan

Problems were caused by used paper in each area are common problems, especially in urban area, for example Medan city. Types rubbish were generated from household level to the level of industries different, namely organic and inorganic. Example of organic rubbish is a used paper. One of the countermeasures for used paper are not to accumulate by collecting and selling used paper for recycling. The purpose of this study was to identify source used paper, the economic value and the benefits and the flow of marketing of used paper were collected and sold by people in the city of Medan. Based interviews with respondents, the source used paper were from household, market, office, shop and newspaper distributor. The greatest economic value is major collector that Rp. 115.162.500,- of year per respondent. The lowest economic value is collector that Rp. 1.055.000,- of year per respondents. Collected and sold of used paper while were contributing to the collectors that 27,85 % to total income respondents of month; the minor collectors that 38,87 % to total income respondents of month and the major collectors that 68,96 % to total income respondents of month. The flow are marketing of used paper from collectors, minor collectors, major collectors and end at the used paper mill

Gambaran Tingkat Pengetahuan Dan Sikap Remaja Putri Terhadap Keputihan Di SMA Negeri 2 Pontianak Tahun 2013

Background. Leucorrhea is a reproductive health problem that almost75% of women at all ages experienced, both physiological andpathological. The study show that 75% women worldwide sufferleucorrhea at least once in their life. Female adolescent is a group thathad susceptible to leucorrhea problem. Objective. The purpose of theresearch was to know the distribution of knowledge and attitude aboutleucorrhea in SMAN 2 pontianak on 2013. Metodology. This study was adescriptive observational study with cross-sectional design. The samplefor this study are 59 sample. Date were obtained trought quetionnaires.Result. Of the 59 sample obtained, 44 sample (74,6%) have highknowledge, 46 sample (78%) have positive attitude. Conclusion. It wasconcluded that sample have good knowledge and positive attitude. Thebetter knowledge of a person to an object that it will better the personattitude toward the object

A Flexible z-Tree Implementation of the Social Value Orientation Slider Measure (Murphy et al. 2011) – Manual

This manual describes a z-Tree (Fischbacher, 2007) implementation of the paper-based Social Vaule Orientation (SVO) Slider Measure by Murphy et al. (2011). Using the paper-based version instead of the slider-based version (as implemented on the SVO-Website) avoids server-traffic related delays we experienced in the latter implementation

Motion of condensates in non-Markovian zero-range dynamics

Condensation transition in a non-Markovian zero-range process is studied in one and higher dimensions. In the mean-field approximation, corresponding to infinite range hopping, the model exhibits condensation with a stationary condensate, as in the Markovian case, but with a modified phase diagram. In the case of nearest-neighbor hopping, the condensate is found to drift by a "slinky" motion from one site to the next. The mechanism of the drift is explored numerically in detail. A modified model with nearest-neighbor hopping which allows exact calculation of the steady state is introduced. The steady state of this model is found to be a product measure, and the condensate is stationary.Comment: 31 pages, 9 figure