Negative-Inertia Converters: Devices Manifesting Negative Mass and Negative Moment of Inertia

Abstract

Negative inertia is an unusual and counter-intuitive property of matter, extensively investigated in some of the most exotic branches of physics and engineering at both macroscopic and microscopic levels. Such an exotic property promises a wide range of applications, from Alcubierre drive to acoustic wave manipulation. Here, a novel approach to the realization of negative inertia and the concept of negative-inertia converters are introduced for both translational and rotational motion. The proposed devices, capable of exhibiting negative mass and negative moment of inertia, base their operational principle on actuating the loading inertia, concealed within the housing of the device, synchronously with the displacement of the housing itself. Negative-inertia converters share many similarities with negative-impedance converters, including their proneness to instability. Thus, an equivalent circuit model of the proposed devices is developed and simulated in lossless and lossy environments. Friction, unavoidable in every practical system, is found to be the main cause of instability. The derived closed-form stability condition suggests that the effective inertia of a system containing a negative-inertia converter must remain positive to ensure the stability. Despite this limitation, negative-inertia converters may become the key elements in applications requiring reduction of an object’s inertia.

Negative Electrical Conductivity Metamaterials

“…Our paper is devoted to the possibility of realization of negative thermal conductivity meta-materials, which were introduced recently in ref. 22. We suggest the model meta-material system demonstrating negative electrical conductivity emerging from the negative effective mass of the charge carriers.…”

The Effect of Negative Mass in Gravitating System<strong> </strong>

“…In particular, metamaterials with controllable and negative bulk modulus were demonstrated, exploiting the effect of the negative mass [10,[11][12][13]17]. A number of experimental exemplifications of the "negative mass effect" were already demonstrated [11][12][13][18][19]. Use of the plasma oscillations of the free electron gas for the realization of the negative mass effect was suggested [20][21].…”