Prof. Rati Ram Sharma
Space and time are not real substantive,tangible entities but abstract concepts. The concept of space evolves from our life long perceptions of successive 'there, here, there' and that of time from successive 'then, now, then' all arising from the successive motions and changes in the surrounding objects. The concept of only forward and never backward motion of the 'time arrow' arises from the irreversibility of basic natural processes generating the time concept.
Electromagnetic radiations including light are 'waves' existing in and composed by the propagating real physical medium in space.
The space and time, being intangible abstract concepts,cannot fuse into any tangible, concrete spacetime continuum to propagate electromagnetic and gravitational waves. A non-composite static spacetime continuum cannot undulate to propagate transverse EM wave. All spacetime continua of four or higher dimensions are mere mathematical constructs bereft of physical existence. Theories based on those spacetime continua are unrealistic.
Observed inter-conversions of various forms of energy among themselves and/or with mass inescapably suggest the existence of a 'Basic Substance' composing all forms of energy & mass.
Work of Young, Fresnel & Sagnac on interference & diffraction of light prove light as wave, hence composed by its medium. Inter-conversion of light (photon) and matter (electron-positron pair)suggest composition unity & continuity of mass, material particles, energy & energy quanta. So light propagating space medium emerges as the 'Basic Substance' to compose all. It is NOT a continuum but a 'kinetic gas' composed by a new particle, 'sharmon' comprising basic elements : positrino & negatrino, named 'cosminos' for composing all in the Cosmos.
A charge, electric or gravitational i.e. mass, is an innate, inseparable property of the particle. Massless and mass or charge generating particle, like Higgs, or space vortex or space toroid are non-existent.
An element, being non-composite, has only single charge to give it isotropic, homogeneous property. Multiple charges imply same many constituents. Mass and electric charge inseparably unite and unify into the gravitoelectric charge or the cosmino (positrino, negatrino)itself. Gravitational & electromagnetic force/field unify into a gravitoelectromagnetic force/field. A force/field and corresponding charge manifest via mutual feeling.The electric, magnetic, electromagnetic and gravitational force/field have common origin/cause and common mediator in the cosminos having electric charge and mass.
Centripetal & centrifugal forces:Since a force equals the product of mass and acceleration, the acceleration goes with the force. For the circular motion of radius r of a body of mass m at a tangential constant velocity V the attendant continuous change of direction of motion inward creates a centripetal acceleration -V^2/r inward associated with the centripetal force -mV^2/r, which is equally opposed by a centrifugal force +mV^2/r outward, the two together keeping the body at rest radially. The corresponding centripetal and centrifugal mechanical forces remain un-manifested without creating body's radial motion inward or outward.The tangential velocity V remains constant without acceleration indicating absence of the associated tangential component of the force. At the instant of snapping its connection the moving body flies away tangentially with the velocity V due to inertia of motion and both the centripetal and centrifugal forces disappear instantly. Thus both centripetal and centrifugal mechanical forces are real though remain un-manifested and there is no tangential component of the force to accelerate the constant tangential velocity.