# Plotting and Animating 3D Vectors

I'd like to plot 3-D vectors (arrows) on a spherical shell given as in: https://www.google.com.pk/search?q=Bloch+sphere&espv=2&source=lnms&tbm=isch&sa=X&ved=0ahUKEwibk5v9k7fQAhXHthoKHUxoCt4Q_AUICCgB&biw=1360&bih=662#imgrc=Z3va-OLlWqIExM%3A

I'd then like to table the different vectors for different times and create an animation of the evolution of the vectors.

How should one go about it?

The expression I essentially wish to plot is:

$$\vec{n}(\tau) = \Big ( e^{- \gamma(\tau)} \sin \theta \cos \phi, e^{- \gamma(\tau)} \sin \theta \sin \phi, \cos \theta \Big ),$$

where $\gamma$ is some function of the time, $\tau$.

• The functions you need to use are E, Sin, Cos. You put your formula inside an Arrow statement, inside a Table statement that varies time. Use Graphics3D to show everything. Put a Sphere in the background with low Opacity. When it all works, wrap it in an Animate. – Nicholas G Nov 20 '16 at 11:41
• Have you seen the Vector Visualization guide? – Edmund Nov 20 '16 at 11:48
• Have you seen the Bloch vector animation near the end of this post ? – LouisB Nov 21 '16 at 5:46