The passive properties of skeletal muscle play an important role in muscle function. While the passive quasi-static elastic properties of muscle fibers have been well characterized, the dynamic visco-elastic passive behavior of fibers has garnered less attention. In particular, it is unclear how the visco-elastic properties are influenced by lengthening velocity, in particular for the range of ...

We consider collisional models for granular particles and analyze the conditions under which the restitution coefficient might be a constant. We show that these conditions are not consistent with known collision laws. From the generalization of the Hertz contact law for viscoelastic particles we obtain the coefficient of normal restitution ǫ as a function of the normal component of the impact v...

A novel approach based on spatiotemporal differentialoperators is developed here for broadband, velocity-dependent scattering. Unlike the spectral-domain representations, the new method facilitates a compact formulation for scattering by arbitrary excitation signals, in the presence of moving objects. In free space (vacuum), relativistically exact formulas are developed. After developing the ge...

We use the recently developed model of the electron spins within Earth to investigate all of the six possible long-range velocity-dependent spin-spin interactions associated with the exchange of an ultralight (mz'<10(-10) eV) or massless intermediate vector boson. Several laboratory experiments have established upper limits on the energy associated with various fermion-spin orientations relativ...

F. Pinsker,1,* W. Bao,2 Y. Zhang,3,4 H. Ohadi,5 A. Dreismann,5 and J. J. Baumberg5 1Department of Physics, Clarendon Laboratory, University of Oxford, Parks Road, Oxford OX1 3PU, United Kingdom 2Department of Mathematics, National University of Singapore, 119076 Singapore 3Beijing Computational Science Research Center, Beijing 100094, People’s Republic of China 4Université de Rennes 1, IRMAR, C...

The tired-light interpretation of the cosmological redshift is as old as the discovery of the phenomenon itself, and a number of mechanisms have been proposed by researchers in cosmology. This article presents the basic ideas behind the author's recent proposal of an inertial induction model consisting of both velocity-and acceleration-dependent terms which can explain the cosmological redshift...

Charge transport in semiconducting single-walled nanotubes (SWNTs) with Schottky-barrier contacts has been studied at high bias. We observe nearly symmetric ambipolar transport with electron and hole currents significantly exceeding 25 microA, the reported current limit in metallic SWNTs due to optical phonon emission. Four simple models for the field-dependent velocity (ballistic, current satu...

Quantum phase slips are the primary excitations in one-dimensional superfluids and superconductors at low temperatures but their existence in ultracold quantum gases has not been demonstrated yet. We now study experimentally the nucleation rate of phase slips in one-dimensional superfluids realized with ultracold quantum gases, flowing along a periodic potential. We observe a crossover between ...

Friction forces in the tip-sample contact govern the dynamics of contact mode atomic force microscopy. In ambient conditions typical contact radii between tip and sample are in the order of a few nanometers. In order to account for the large interaction area the dynamics of contact mode atomic force microscope (AFM) is investigated under the assumption of a multi-asperity contact interface betw...

We propose a variable Eddington factor, depending on the flow velocity v, for the relativistic radiative flow, whose velocity becomes of the order of the speed of light. When the gaseous flow is radiatively accelerated up to the relativistic regime, the velocity gradient becomes very large in the direction of the flow. As a result, the radiative diffusion may become anisotropic in the comoving ...