Negative mass using negative mass that requires no energy input and no reaction mass to achieve arbitrarily high acceleration. Forward also coined a term, "nullification", to describe what happens when ordinary matter and negative matter meet: they are expected to be able to cancel out or nullify each other's existence. An interaction between equal quantities of positive mass matter (hence of positive energy ) and negative mass matter (of negative energy ) would release no energy, but because the only configuration of such particles that has zero momentum (both particles moving with the same velocity in the same direction) does not produce
Binary mass function a single-lined spectroscopic binary if the radial motion of only one of the two binary components can be measured. In this case, a lower limit on the mass of the "other" (unseen) component can be determined. The true mass and true orbital velocity cannot be determined from the radial velocity because the orbital inclination is generally unknown. (The inclination is the orientation of the orbit from the point of view of the observer, and relates true and radial velocity.) This causes a degeneracy between mass and inclination. For example, if the measured radial velocity is low, this can mean that