Riemann tensor in normal coordinates

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The discussion revolves around finding a simplified expression for the Riemann tensor in normal coordinates, emphasizing the relationship between the Riemann tensor and the connection. The original poster notes that their solution appears too simple for a question worth three marks, as they derived a two-term expression based on the derivatives of the connection. Another participant points out that to fully address the question, one must derive the general form of the Riemann tensor in normal coordinates and expand the connections to achieve a four-term expression involving second derivatives of the metric tensor. The conversation highlights the need for a more comprehensive approach to meet the expectations of the marks allocated.
alcoholicsephiroth
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This is essentially a "homework question", but I'm not looking for an explicit solution so I have posted it here.

1. Homework Statement

Find a simplified expression for the Riemann tensor in terms of the connection in normal coordinates.

2. Homework Equations

Riemann tensor = (derivative of connection term) - (derivative of connection term) - (connection term)(connection term) - (connection term)(connection term)

3. The Attempt at a Solution

My solution is

Riemann tensor = (derivative of connection term) - (derivative of connection term)

, where I have used the fact that the connections evaluated at point P are all 0, but their derivatives are not necessarily 0.




My problem is that 3 MARKS are allocated to this question (from a possible 60 marks in a 2 hour paper), and that this looks far too simple a solution for 3 marks.

What am I missing?

Trev
 
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alcoholicsephiroth said:
My problem is that 3 MARKS are allocated to this question (from a possible 60 marks in a 2 hour paper), and that this looks far too simple a solution for 3 marks.

What am I missing?

A 3-point question of this type tells you that you have to first determine what the general form of the Riemann tensor is in normal coordinates and then expand the connections to obtain a four-term expression for the Riemann tensor where all terms are made of the second derivatives of the metric tensor.

AB
 
In an inertial frame of reference (IFR), there are two fixed points, A and B, which share an entangled state $$ \frac{1}{\sqrt{2}}(|0>_A|1>_B+|1>_A|0>_B) $$ At point A, a measurement is made. The state then collapses to $$ |a>_A|b>_B, \{a,b\}=\{0,1\} $$ We assume that A has the state ##|a>_A## and B has ##|b>_B## simultaneously, i.e., when their synchronized clocks both read time T However, in other inertial frames, due to the relativity of simultaneity, the moment when B has ##|b>_B##...

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