I'm trying to reproduce the examples in the page, starting with
"Schwarzschild spacetime"
So far I'm getting the following:
* When defining a `Chart`, say `X`, t
from manifolds.all import *
M = Manifold(4, 'M', r'M'); M
X = Chart(M, r't, r:positive, th:positive:\theta, ph:\phi', 'BL')
X
does not return the latex output, but this
chart 'BL' (t, r, th, ph)
this is not a problem because after trying
X.show()
the expected output pops up!
When using the `show()`method on the metric the output is not shown in the
way I expected (with the tensor product of the basis,
g[0,0], g[1,1], g[2,2], g[3,3] = -(1 - 2*m/r), 1/(1 - 2*m/r), r^2, (r*sin(th
))^2; show(g)
g = (2*m/r - 1) dt*dt - 1/(2*m/r - 1) dr*dr + r^2 dth*dth +
r^2*sin(th)^2 dph*dph
I try a couple of things and non of them yields the result shown in the
documentation. Similar behaviour goes on and on through the WS.
* I'd add the following line to the WS
nab[:]
because people can see the components of the connection.
* Additionally, I shall propose to define a method to show only the
non-trivial components of the tensors... including the `name` of the
component (in indices). The code below will do the work, but of course it
can be improved.
for i in M.irange():
for j in M.irange():
for k in xrange(j,M.dimension()):
if (nab[:][i][j][k] != 0):
print "Gam_{%d %d %d}: " %(i, j, k)
print "\t", nab[:][i][j][k], "\n\n"
This method should be implemented for tensors.
I'm still learning the stuff, and should be posting more suggestions later!
Thank you for the wonderful work done with this package!!! Cheers
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