I have the expression ##g_{ab}=\eta_{ab}+\epsilon h_{ab}##,(adsbygoogle = window.adsbygoogle || []).push({});

The indices on ##h^{ab}## are raised with ##\eta^{ab}## to give ##g^{ab}=\eta^{ab}-\epsilon h^{ab}##

I am not seeing where the minus sign comes from.

So I know ##\eta^{ab}\eta_{bc}=\delta^{a}_{c}## and ##h^{ab}=\eta^{ac}\eta^{bd}h_{cd}## ,

And that ##\eta_{ab}## has signature ##(-,+,+,+)##,

Any help greatly appreciated.

**Physics Forums - The Fusion of Science and Community**

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Weak field approx raising index using minkowski metric

Loading...

Similar Threads - Weak field approx | Date |
---|---|

I How to derive weak-field Schwarzschild metric from LEFE's? | Mar 27, 2017 |

I General Relativity and Newtonian Weak Field | Aug 27, 2016 |

Hamiltonian of weak gravitational field | Jun 19, 2015 |

Weak Field Approx, algebra geodesic equation | Mar 10, 2015 |

GR weak field approx. problem with Dunsby's notes | Sep 7, 2009 |

**Physics Forums - The Fusion of Science and Community**