Finally getting to flat coordinates

  
  DefineTensor[gpp,"gpp",{{2,1},1}]

  PermWeight::sym: Symmetries of gpp assigned

  PermWeight::def: Object gpp defined

In[45]:=

  
  Ttransform[gpp,gp[la,lb],{q,thp,t},{q, thp/(1 - 4 G M),t},-1]

  Components assigned to gpp

In[46]:=

  
  gpp[-2,-2]

Out[46]=

   2
  q

Here is the final form of the transformed metric:

In[47]:=

  
  Table[gpp[-i,-j],{i,3},{j,3}]

Out[47]=

                   2
  {{1, 0, 0}, {0, q , 0}, {0, 0, -1}}

Okay this looks like flat polar coordinates. But this isn't ordinary flat spacetime in polar coordinates.
CAN YOU GUESS WHY NOT?

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