Solving Timescales Physics Problems: Timesteps and Normal Distribution Analysis

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The discussion focuses on deriving the relationship between timesteps and normal distribution in physics problems. It establishes that the mean is represented as μδt, leading to the equation S_{i+1} = S_i(1 + μδt). After M timesteps, the expression for S_m is approximated as S_m = S_0e^{μT}. Participants inquire about the derivation of this approximation and whether a Taylor series is involved, but it is clarified that it stems from the definition of "e." The conversation emphasizes the mathematical foundations of these relationships in solving physics problems.
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Hello all

Let \delta t be a timestep. Then the mean is equaled to \mu\delta t where \mu is a constant. Assuming a nornal distribution, \frac{S_{i+1}-S_{i}}{S_i} = \mu\delta t

S_{i+1} = S_i(1 + \mu\delta t). Hence after M timesteps we have:

S_m = S_0(1+\mu\delta t)^M = S_0e^{Mlog(1+\mu\delta t)} \doteq S_{M}=S_{0}e^{[\mu M(\delta t)]}= S_0e^{\mu T} How do we get the last part (the approximation)?

Thanks :smile:
 
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The way i see it,the approximation should be
S_{M}=S_{0}e^{[\mu M(\delta t)]}

It might help if you came up with more explanation.

Daniel.
 
yes that is correct. how do they get this? do they use taylor series?
 
No,the definition of "e"...Check one of the other threads where i showed you on a similar problem...

Daniel.
 
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