Undergrad Derivation notation with capital D?

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The discussion centers on the derivation notation ##\frac{Ds}{\mathrm{d}\tau}## encountered in a General Relativity script, which initially puzzled the participants. It was clarified that this notation is commonly used to denote the induced connection along a curve, specifically represented as ##\nabla_{\dot\gamma} s##. The notation is not a formatting error, but rather a standard representation for derivatives with respect to a curve parameter. The confusion arose due to the notation not being introduced earlier in the text. Ultimately, the notation is linked to the induced Levi-Civita connection in the context of gyroscopic precession.
Emil_M
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Hi, I came across a derivation notation I didn't recognize:
Let ##s## be some four-vector and ##\tau## the proper time. What is the significance of
$$\frac{Ds}{\mathrm{d}\tau}?$$

I know ##Ds## can be used to mean the Jacobian, but I've never come across the notation above. Does someone recognize it?
 
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Where did you come across this notation? It should be explained there what is meant by the notation. If we cannot see the text we are just stabbing in the dark.
 
I came across this notation in one of my General Relativity scripts, but I checked the entire text before posting and this notation is not introduced in the script. I guess the author believes the notation is commonplace enough not to need an introduction. The only time ##D_X## was used in the context of derivations was in a prove for the linearity of covariant derivatives as an alternative symbol for ##\nabla_x##.

However, ##D## really doesn't make sense in the context of a covariant derivative here, as I wouldn't know what the operator ##\frac{D}{\mathrm{d}\tau}## means?

Specifically, the above notations appears in a chapter about Gyroscopic Precession:
48841_Screen_Shot_2018-02-15_at_14.07.04.jpg
 

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Ah ok, the notation is introduced three pages further down... I guess this is a just a formatting error of the author

Thanks for the help, though!
 
It is not a formatting error. It is a somewhat standard notation for the induced connection.
 
martinbn said:
It is not a formatting error. It is a somewhat standard notation for the induced connection.
Just to be a bit more specific; the derivative along a curve ##\gamma## with respect to the curve parameter, i.e.,
$$
\frac{Ds}{d\tau} = \nabla_{\dot\gamma} s = \dot x^\mu \nabla_\mu s,
$$
for the induced Levi-Civita connection.
 
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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