Spacetime paths

  ParametricPlot3D[{{x[t,.7,Pi/1.45],y[t,.7,Pi/1.45],t},
{x[t,.7,-Pi/1.45],y[t,.7,-Pi/1.45],-t},{x[t,.7,Pi/1.7],y[t,.7,Pi/1.7],t},
{x[t,.7,-Pi/1.7],y[t,.7,-Pi/1.7],-t},{x[t,.7,Pi/2],y[t,.7,Pi/2],t},
{x[t,.7,-Pi/2],y[t,.7,-Pi/2],-t}},{t,-5,5}, AspectRatio -> 1]

Out[159]=

  -Graphics3D-

In[160]:=

  Show[%, ViewPoint->{0.000, 0.000, 3.384}]

Out[161]=

  -Graphics3D-

In[162]:=

  Show[%, ViewPoint->{0.056, -3.383, -0.031}]

Out[163]=

  -Graphics3D-

In[164]:=

  Show[%, ViewPoint->{-3.381, -0.092, -0.099}]

Out[165]=

  -Graphics3D-

In[166]:=

  ParametricPlot3D[{{x[t,.7,Pi/1.45],y[t,.7,Pi/1.45],-t},
{x[t,.7,-Pi/1.45],y[t,.7,-Pi/1.45],t},{x[t,.7,Pi/1.7],y[t,.7,Pi/1.7],-t},
{x[t,.7,-Pi/1.7],y[t,.7,-Pi/1.7],t},{x[t,.7,Pi/2],y[t,.7,Pi/2],-t},
{x[t,.7,-Pi/2],y[t,.7,-Pi/2],t}},{t,-5,5}, AspectRatio -> 1]

Out[167]=

  -Graphics3D-

In[168]:=

  Show[%, ViewPoint->{0.000, 0.000, 3.384}]

Out[169]=

  -Graphics3D-

In[170]:=

  Show[%, ViewPoint->{0.056, -3.383, -0.031}]

Out[171]=

  -Graphics3D-

In[172]:=

  Show[%, ViewPoint->{-3.381, -0.092, -0.099}]

Out[173]=

  -Graphics3D-

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