Wrong signs Ricci tensor components RW metric tric

In summary, the person is working on deriving the Friedmann equations from the RW metric with a (+,-,-,-) signature. They succeeded except for getting the opposite sign for the Ricci tensor components and the Ricci scalar. However, they calmly ignored the wrong signs and substituted them into the Einstein equations, which still worked and matched values in textbooks. They are curious about what they did wrong and ask for ideas. The conversation ends with a suggestion to check the sign convention and the energy momentum stress tensor for perfect fluid as it may be the cause of the discrepancy.
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enomanus
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Hi, I am working through GR by myself and decided to derive the Friedmann equations from the RW metric w. ( +,-,-,-) signature. I succeeded except that I get right value but the opposite sign for each of the Ricci tensor components and the Ricci scalar e.g. For R00 I get +3R../R not -3R../R . I calmly ignored the wrong signs and substituted the opposite sign into the Einstein equations because 1. they worked and 2. it matched the values for G00 G11 given in textbooks. Obviously I am curious as to what I did wrong! Any ideas?? Thanks !
 
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What is the Ricci tensor?

The Ricci tensor is a mathematical object used in the study of Riemannian geometry, which is a branch of mathematics that deals with curved spaces. It is used to describe the curvature of a space at a given point.

What are wrong signs in the Ricci tensor components?

Wrong signs in the Ricci tensor components refer to a sign error in the calculation of the tensor. This can lead to incorrect results and must be carefully checked for in any calculations involving the Ricci tensor.

What is the RW metric?

The RW metric, also known as the Robertson-Walker metric, is a mathematical model used to describe the geometry of the universe. It is based on the theory of general relativity and is used to study the large-scale structure of the universe.

What does the tric in "RW metric tric" stand for?

The "tric" in "RW metric tric" stands for "trichotomy", which refers to the three possible states of curvature in the RW metric: positive, negative, or zero.

How are wrong signs in the Ricci tensor components related to the RW metric tric?

The wrong signs in the Ricci tensor components can affect the calculation of the RW metric, leading to incorrect results for the curvature of the universe. It is important to carefully check for these errors in order to accurately understand the geometry of the universe.

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