An understanding of the oscillations of differentially rotating systems is key to many areas of astrophysics. It is of particular relevance to the emission of gravitational waves from oscillating neutron stars, which are expected to possess significant differential rotation immediately after birth or binary merger. In a previous paper we analysed the normal modes of a simple system exhibiting d...

Using certain ideas connected with the entropy theory, several kinds of dimensions are introduced for arbitrary topological spaces. Their properties are examined, in particular, for normal spaces and quasi-discrete ones. One of the considered dimensions coincides, on these spaces, with the Čech-Lebesgue dimension and the height dimension of posets, respectively.

Transition frequencies of two spherical gas bubbles interacting in an acoustic field are discussed theoretically. In the present study, transition frequency is defined as the frequency of external sound for which the phase difference between a bubble’s pulsation and the external sound is π/2. It is shown by a linear theory that a bubble interacting with a neighboring bubble has three (or fewer)...

We present a preliminary study of a chiral-gauge-invariant Wilson term for the Standard Model on a lattice. In the strong coupling limit for doublers, this Wilson term shows that the doublers of leptons (baryons) are antibaryons (anti-leptons), and they are decoupled by getting gauge invariant masses. We discuss that the possibility of achieving the low-energy Standard Model could be realized b...

Image-based vibration mode identification gained increased attentions in civil and construction communities. A recent video-based motion magnification method was developed to measure and visualize small structure motions. This new approach presents a potential for low-cost vibration measurement and mode shape identification. Pilot studies using this approach on simple rigid body structures was ...

The limitations on the production and profitability of entanglement in a harmonic chain under strong driving are considered. We report on the limits of attainable entanglement for a given set of squeezings of the eigenmodes, showing that, the higher the entanglement, the more oscillatory and thus less easy to profit from. We also comment on propagation properties of entanglement, discussing the...

Humans can discriminate among the hardness of objects by tapping their surfaces. The damped natural vibration caused by tapping and its frequency are known to be the cue for the perception of hardness. This study is an investigation of the characteristics of this perception of hardness, as induced by vibration stimuli including multiple frequency components. We performed a comparative experimen...

ProMode (http://promode.socs.waseda.ac.jp/) is a database collecting the results from normal mode analyses (NMA) of various protein molecules [3]. Although NMA is based on the harmonic approximation, it has been shown by many studies that the results from NMA are not only reasonable qualitatively in most cases, but also can provide a proper description of the functionally important motions of t...