Slower-than-light; having a speed less than light.(adjective)
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Use "subluminal" in a sentence
"It was a dangerous business, as the slightest miscalculation could cause the ship to slide into the subluminal mud and dissipate in a Ĉerenkov blink."
"The idea is that the probability of each of the outcomes is determined by ˜local events,™ i.e., events that are confined to its backward light-cone, and which can only exert subluminal or luminal influences on it (see Figure 3 below); and the distant outcomes are fundamentally independent of each other, and thus their joint probability factorizes."
"Our paper addressed specifically the so-called Einstein-Aether, or new Aether, theories but I am pretty sure that, unless finely tuned, any coupling to gravity would alter the dispersion relation of the graviton to give some subluminal mode that can be radiated in a Cerenkov process."