we know the equation of a simple harmonic wave going to left to right is, y=asin((2π)/λ)(vt−x) if we put t=0 and x=0 , we get y=0 and if we put t=0 and x=0.25λ , we get y= a !! But How could this be possible? How could right side particles start oscillating before the left ones?Don′t we need a certain time gap for right side particles to start oscillating??