Can we have a complex number in the exponent?

Join the discussion
Ask a follow-up here, or get your own question answered by working scientists, mathematicians and engineers — people, not an autocomplete.
Real named experts · corrections over time · the nuance an AI answer skips
2 replies · 1K views
docnet
Messages
796
Reaction score
487
TL;DR
Is it possible to exponentiate a number that is not e to a complex number?
Does it make sense to write ##r^c##
where ## r\in R/e ## and ##c\in C## ?
 
Physics news on Phys.org
Yes. It makes sense. Remember that using only traditional real functions, ##r = e^{\ln{r}}##. So you can get the complex power of any real number by way of complex powers of ##e##. In fact, it makes sense to raise a complex number to a complex power.
 
Reply
  • Informative
Likes   Reactions: docnet
##r^c = e^{c \log(r)}##
Both r and c can be complex here. As a notable example, ##i^i = e^{i \log{i}} = e^{i (\frac{\pi}{2} i)} = e^{- \frac{\pi}{2}}## which is real.
 
Reply
  • Informative
Likes   Reactions: docnet