Mechanical Failure of Solid Polymers

Abstract

We investigate the vacuum expectation values of the energy-momentum tensor and the fermionic condensate associated with a massive spinor field obeying the MIT bag boundary condition on a spherical shell in the global monopole spacetime. In order to do that, we use the generalized Abel-Plana summation formula. As we shall see, this procedure allows us to extract from the vacuum expectation values the contribution coming from the unbounded spacetime and to explicitly present the boundary induced parts. As regards the boundary induced contribution, two distinct situations are examined: the vacuum average effects inside and outside the spherical shell. The asymptotic behaviour of the vacuum densities is investigated near the sphere centre and near the surface, and at large distances from the sphere. In the limit of strong gravitational field corresponding to small values of the parameter describing the solid angle deficit in the global monopole geometry, the sphere induced expectation values are exponentially suppressed. We discuss, as a special case, the fermionic vacuum densities for the spherical shell on the background of the Minkowski spacetime. Previous approaches to this problem within the framework of the QCD bag models have been global and our calculation is a local extension of these contributions.

Study of edge radiation at HiSOR storage ring

“…Analytical estimations of ER intensity in zerofrequency approximation [11][12][13], as well as subsequent numerical simulations of ER characteristics [14][15][16][17][18][19][20][21][22] show its significant advantage as a source of infrared radiation. In this spectral region, ER should be higher in intensity than that of a standard synchrotron radiation.…”

IR–UV edge radiation at Siberia-2 storage ring

“…However, while ER from relativistic protons is characterized by wavelengths much shorter than the synchrotron radiation critical wavelength in the same magnet, ER from relativistic electrons manifests itself in the longwave spectral range, with wavelengths much longer than the synchrotron radiation critical wavelength. This useful feature of ER in electron storage rings, once noted in the first theoretical works [4,[9][10][11], is widely discussed in the succeeding papers [12][13][14][15][16][17][18][19]. Measurements of long-wave ER [20][21][22][23] strengthened the belief that electron beam ER can be used as a bright source of electromagnetic radiation in the infrared-vacuum ultraviolet spectral range.…”

Creep and the time dependence of the strength in rocks

“…Good agreement with (1) has been found in some metals [1], in silver chloride crystals [2], in polymers [3], and in watery plaster of Paris (Griggs, 1936), carnallite salts (Vodop'yanova and Urazova, 1964), single crystals of rock salt (Manke, 1934), and weak rocks (Fisenko, 1965).…”