Inflation from Tsunami-waves

We investigate inflation driven by the evolution of highly excited quantum states within the framework of out of equilibrium field dynamics. These states are characterized by a non-perturbatively large number of quanta in a band of momenta but with vanishing expectation value of the scalar field.They represent the situation in which initially a non-perturbatively large energy density is localized in a band of high energy quantum modes and are coined tsunami-waves. The self-consistent evolution of this quantum state and the scale factor is studied analytically and numerically. It is shown that the time evolution of these quantum states lead to two consecutive stages of inflation under conditions that are the quantum analogue of slow-roll. The evolution of the scale factor during the first stage has new features that are characteristic of the quantum state. During this initial stage the quantum fluctuations in the highly excited band build up an effective homogeneous condensate with a non- perturbatively large amplitude as a consequence of the large number of quanta. The second stage of inflation is similar to the usual classical chaotic scenario but driven by this effective condensate.The excited quantum modes are already superhorizon in the first stage and do not affect the power spectrum of scalar perturbations. Thus, this tsunami quantum state provides a field theoretical justification for chaotic scenarios driven by a classical homogeneous scalar field of large amplitude.Comment: LaTex, 36 pages, 7 .ps figures. Improved version to appear in Nucl. Phys.

Pemodelan Numerik Tsunami untuk Mengestimasi Waktu Tiba dan Ketinggian Maksimum Gelombang Tsunami di Teluk Amurang

Amurang Bay is a coastal area of South Minahasa Regency which is densely populated but faces the subduction zone of North Sulawesi which has the potential to generate earthquakes that trigger a tsunami. The process of the tsunami disaster occurred quickly, but the impact was very destructive and caused many casualties. This study aims to determine the propagation of tsunami waves with the worst scenario Mw 8.5 in Amurang Bay. Numerical methods in COMCOT software are used to model the propagation of tsunami waves in order to obtain an estimate of arrival time and maximum height of tsunami waves. Based on this modeling, the estimated arrival time of tsunami waves at the virtual tide gauge point in Amurang Bay is in the range of 8–11 minutes. The maximum height of tsunami waves is included in the alert category, which is 9.55 meters to 11.44 meters. The fastest estimated arrival time was recorded in Amurang Barat District and maximum height of tsunami waves was found in Tumpaan District. The results of this modeling can be used as one of the steps for mitigating tsunami disaster by preparing the surrounding community and assisting the evacuation process when a tsunami disaster occurs

Oceanographic features of a submarine eruption that destroyed the Kaiyo-Maru No. 5

When Myojinsho Reef erupted in September 1952, tsunami waves were recorded several times by a. self-registering wave gauge installed on the southwestern coast of Hachijo Island about 130 km from that Reef. The largest one of these tsunamis appeared on 24 September, and it is presumed that this wave ca.used the destruction of the KAIYO-MARU No. 5. Results of investigation of these recorded tsunami waves and other phenomena are reported

The VOLNA code for the numerical modelling of tsunami waves: generation, propagation and inundation

A novel tool for tsunami wave modelling is presented. This tool has the potential of being used for operational purposes: indeed, the numerical code \VOLNA is able to handle the complete life-cycle of a tsunami (generation, propagation and run-up along the coast). The algorithm works on unstructured triangular meshes and thus can be run in arbitrary complex domains. This paper contains the detailed description of the finite volume scheme implemented in the code. The numerical treatment of the wet/dry transition is explained. This point is crucial for accurate run-up/run-down computations. Most existing tsunami codes use semi-empirical techniques at this stage, which are not always sufficient for tsunami hazard mitigation. Indeed the decision to evacuate inhabitants is based on inundation maps which are produced with this type of numerical tools. We present several realistic test cases that partially validate our algorithm. Comparisons with analytical solutions and experimental data are performed. Finally the main conclusions are outlined and the perspectives for future research presented.Comment: 47 pages, 27 figures. Other author's papers can be downloaded at http://www.lama.univ-savoie.fr/~dutykh

Modelling the effects of tsunami-induced forces on building facades

Tsunami waves cause severe structural and nonstructural damages in the shallow water and inundation areas. The intense development that coastal areas have experienced in the last decades, with a rapid growth in population and economy, has increased their exposure to tsunami waves. Recent research on tsunami modelling has been mainly centred in the hydrodynamic issues (e.g., propagation). However, the major losses, human lives and economic, occur at the inland areas, and so further knowledge on what happens in these areas is needed. Main goal of this research is the assessment of inland buildings resilience to tsunami-induced flooding.info:eu-repo/semantics/publishedVersio

Run-up characterstics of symmetrical solitary tsunami waves of unknown shapes

The problem of tsunami wave run-up on a beach is discussed in the framework of the rigorous solutions of the nonlinear shallow-water theory. We present an analysis of the run-up characteristics for various shapes of the incoming symmetrical solitary tsunami waves. It will be demonstrated that the extreme (maximal) wave characteristics on a beach (run-up and draw-down heights, run-up and draw-down velocities and breaking parameter) are weakly dependent on the shape of incident wave if the definition of the significant wave length determined on the 2/3 level of the maximum height is used. The universal analytical expressions for the extreme wave characteristics are derived for the run-up of the solitary pulses. They can be directly applicable for tsunami warning because in many case the shape of the incident tsunami wave is unknown.Comment: Submitted to PAGEOP