Complex powers/logarithmic spirals

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SUMMARY

The discussion centers on the expression w^z = e^(z log w) and its implications in the complex plane, specifically regarding the addition of integer multiples of (2*pi*i) to log w. This addition is equivalent to multiplying w^z by e^(z*2*pi*i), leading to the representation of complex powers as intersections of two logarithmic spirals. The first spiral corresponds to w^z, while the second spiral's significance is explored but not fully clarified. The inquiry is rooted in concepts presented in Roger Penrose's "The Road to Reality," particularly on pages 96-97.

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  • Understanding of complex numbers and their properties
  • Familiarity with logarithmic functions in the complex plane
  • Knowledge of exponential functions and their applications
  • Basic grasp of algebraic rules of exponents
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  • Study the properties of complex logarithms and their geometric interpretations
  • Explore the concept of logarithmic spirals in mathematics
  • Investigate the implications of Euler's formula in complex analysis
  • Read Roger Penrose's "The Road to Reality," focusing on the sections discussing complex powers
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Mathematicians, physics students, and anyone interested in complex analysis and its applications in understanding logarithmic spirals.

hoodwink
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When looking at

w^z = e^(z log w)

I understand that adding any integer multiple of (2*pi*i) to log w is equivalent to a full rotation in the complex plane. I don't understand how this step is equivalent to multiplying w^z by e^(z*2*pi*i). Also, I'm missing the significance of this being represented in the complex plane as the intersections of 2 logarithmic spirals. I can see how the first spiral is given by w^z, but the other?

If anyone has a copy handy, my questions arose from looking at pages 96-97 of The Road to Reality by Roger Penrose.
 
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I think it is just rules of exponents from algebra.

(w^z)*e^(z*2*pi*i) = e^(z log w)*e^(z*2*pi*i) = e^(z log w + z*2*pi*i) =
e^(z(log w + 2*pi*i))

Does this help?
 
click! thanks for that diffy. hopefully those spirals will start to do the same now...:smile:
 

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