Quantum Fluctuations of Black Hole Geometry

By using the minisuperspace model for the interior metric ofstatic black holes, we solve the Wheeler-DeWitt equation to study quantum mechanics of the horizon geometry. Our basic idea is to introduce the gravitational mass and the expansions of null rays as quantum operators. Then, the exact wave function is found as a mass eigenstate, and the radius of the apparent horizon is quantum-mechanically defined. In the evolution of the metric variables, the wave function changes from a WKB solution giving the classical trajectories to a tunneling solution. By virtue of the quantum fluctuations of the metric evolution beyond the WKB approximation, we can observe a static black hole state with the apparent horizon separating from the event horizon.Comment: 18 pages, DPNU-93-3

Analisis Pengaruh Kualitas Pelayanan Terhadap Kepuasan Dan Kepercayaan Pasien Rumah Sakit Umum Shanti Graha Buleleng

Industri kesehatan di wilayah Kabupaten Buleleng dari tahun ke tahun mengalami perkembangan yang berkelanjutan, hal ini menyebabkan terjadinya persaingan untuk mempertahankan dan meningkatkan kuantitas pasien menjadi semakin sulit. Rumah sakit Umum Shanti Graha sebagai salah satu industri yang bergerak dibidang jasa pelayanan kesehatan merasakan dampak dari persaingan industri pelayanan kesehatan ini. Mempertahankan pasien merupakan hal utama yang harus dilakukan oleh Rumah Sakit Umum Shanti Graha. Kualitas pelayanan yang prima dan optimal diharapkan mampu memenuhi harapan pasien, sehingga rumah sakit mampu memenangkan persaingan sehingga tujuan kegiatan operasional USAha secara internal dan eksternal dapat dicapai secara maksimal. Penelitian ini bertujuan untuk mengetahui pengaruh kualitas pelayanan terhadap kepuasan dan kepercayaan pasien. Responden penelitian ini adalah para pasien Rumah Sakit Umum Shanti Graha. Jumlah responden penelitian ditetapkan sebanyak 140 responden dengan pengambilan sampel dilakukan dengan menggunakan metode stratified proportional random sampling. Penelitian ini menggunakan analisis partial least square (PLS) dengan bantuan program software PLS 2.0. Hasil penelitian menunjukan bahwa 1) kualitas pelayanan berpengaruh positif dan signifikan terhadap kepuasan pasien, 2) kualitas pelayanan berpengaruh positif dan signifikan terhadap keprcayaan pasien, 3) kepuasan pasien berpengaruh positif dan signifikan terhadap kepercayaan pasien, sedangkan hipotesis 4) pengaruh kepuasan pasien memediasi sebagian antara kualitas pelayanan terhadap kepercayaan pasien. Implikasi manajerial penelitian ini yaitu Rumah sakit Umum Shanti Graha sebaiknya melakukan perbaikan kinerja dengan meningkatkan kualitas pelayanan khususnya pada indikator-indikator kualitas pelayanan yang berada dibawah rata-rata total, seperti : fasilitas fisik rumah sakit, teknologi rumah sakit yang modern, kemampuan petugas medis rumah sakit yang dapat dipercaya, rasa aman pasien atas pelayanan kesehatan rumah sakit dan ketertarikan pasien dalam memanfaatkan pelayanan kesehatan rumah sakit yang telah di aplikasikan untuk meminimalkan komplain pasien. Kata kunci : Kualitas Pelayanan, Mediasi, Kepuasan Pasien, dan Kepercayaan Pasie

Quantum Monte Carlo study for multiorbital systems with preserved spin and orbital rotational symmetries

We propose to combine the Trotter decomposition and a series expansion of the partition function for Hund's exchange coupling in a quantum Monte Carlo (QMC) algorithm for multiorbital systems that preserves spin and orbital rotational symmetries. This enables us to treat the Hund's (spin-flip and pair-hopping) terms, which is difficult in the conventional QMC method. To demonstrate this, we first apply the algorithm to study ferromagnetism in the two-orbital Hubbard model within the dynamical mean-field theory (DMFT). The result reveals that the preservation of the SU(2) symmetry in Hund's exchange is important, where the Curie temperature is grossly overestimated when the symmetry is degraded, as is often done, to Ising (Z$_2$). We then calculate the $t_{2g}$ spectral functions of Sr$_2$RuO$_4$ by a three-band DMFT calculation with tight-binding parameters taken from the local density approximation with proper rotational symmetry.Comment: 9 pages, 9 figures. Typos corrected, some comments and references adde

Macroscopic quantum dynamics of pi-junctions with ferromagnetic insulators

We theoretically investigate the macroscopic quantum dynamics of a pi junction with a superconductor (S) and a multiferroic material or a ferromagnetic insulator (FI). By deriving the effective action from a microscopic Hamiltonian, a pi-junction qubit (a S-FI-S superconducting quantum interference device ring) is proposed. In this qubit, a quantum two-level system is spontaneously generated and the effect of the quasiparticle dissipation is found to be very weak. These features make it possible to realize a quiet qubit with high coherency. We also investigate macroscopic quantum tunneling (MQT) in current-biased S-FI-S pi junctions and show that the influence of the quasiparticle dissipation on MQT is negligibly small.Comment: 4 pages, 2 figure

Theory of two-dimensional macroscopic quantum tunneling in a Josephson junction coupled with an LC circuit

We investigate classical thermal activation (TA) and macroscopic quantum tunneling (MQT) for a Josephson junction coupled with an LC circuit theoretically. The TA and MQT escape rate are calculated analytically by taking into account the two-dimensional nature of the classical and quantum phase dynamics. We find that the MQT escape rate is largely suppressed by the coupling to the LC circuit. On the other hand, this coupling gives rise to slight reduction of the TA escape rate. These results are relevant for the interpretation of a recent experiment on the MQT and TA phenomena in grain boundary YBCO Josephson junctions.Comment: 4 pages, 1 figure, Proceedings of LT2

Theory of Macroscopic Quantum Tunneling and Dissipation in High-Tc Josephson Junctions

We have investigated macroscopic quantum tunneling (MQT) in in-plane high-Tc superconductor Josephson junctions and the influence of the nodal-quasiparticle and the zero energy bound states (ZES) on MQT. We have shown that the presence of the ZES at the interface between the insulator and the superconductor leads to strong Ohmic quasiparticle dissipation. Therefore, the MQT rate is noticeably suppressed in comparison with the c-axis junctions in which ZES are completely absent.Comment: 4 pages. 1 figur

Two-dimensional macroscopic quantum dynamics in YBCO Josephson junctions

We theoretically study classical thermal activation (TA) and macroscopic quantum tunneling (MQT) for a YBCO Josephson junction coupled with an LC circuit. The TA and MQT escape rate are calculated by taking into account the two-dimensional nature of the classical and quantum phase dynamics. We find that the MQT escape rate is largely suppressed by the coupling to the LC circuit. On the other hand, this coupling leads to the slight reduction of the TA escape rate. These results are relevant for the interpretation of a recent experiment on the MQT and TA phenomena in YBCO bi-epitaxial Josephson junctions.Comment: 9 pages, 2 figure