Sounds Great!...except for those dang pesky Laws of Thermodynamics.
Well, what UCANSEE2 said isn’t contradicted by the laws of thermodynamics. If the universe is a closed system, then it is going to tend towards entropy, which is simply the equilibrium state, or the point where the sine wave crosses zero. It’s perfectly logical that a sine wave can continue vibrating while at the same time tending towards zero. Just look at what happens when you throw a rock in the water: the waves spread out, the amplitude continually decreases, but they never stop being waves.