Is 0=i2pie Possible in Complex Exponentials?

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Discussion Overview

The discussion revolves around the equation 0=i2π in the context of complex exponentials, exploring the implications of equating different expressions involving the exponential function and complex numbers. Participants examine the properties of the exponential function, particularly Euler's formula, and the implications of equality in the complex plane.

Discussion Character

  • Debate/contested
  • Mathematical reasoning
  • Conceptual clarification

Main Points Raised

  • Some participants assert that since e^0=1 and e^(i2π)=1, it follows that 0=i2π, questioning the validity of this conclusion.
  • Others point out that the assumption that ea=eb implies a=b for all complex numbers is not necessarily true, prompting a discussion on the injectivity of the exponential function in the complex domain.
  • A participant suggests that if 0=i2π is true, it could lead to further implications such as 0=0+ai, where a is any real number, raising questions about the nature of equality in the complex plane.
  • Some participants highlight that the complex exponential function is periodic with a period of 2π, indicating that equalities involving complex exponentials must consider additive constants of the form n2π, where n is an integer.
  • There is a challenge regarding the interpretation of equality in the context of complex numbers, with references to the cosine function and its periodicity.

Areas of Agreement / Disagreement

Participants express differing views on the implications of the equation 0=i2π, with some supporting the initial claim and others challenging the assumptions behind it. The discussion remains unresolved, with multiple competing perspectives on the properties of complex exponentials and equality.

Contextual Notes

Participants note that the exponential function with complex arguments is not injective, and the implications of periodicity must be considered when discussing equalities involving complex exponentials. There is also an exploration of the assumptions underlying equality in the complex plane.

johann1301
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0=i2pie !?

We know that any number to the power of zero equals one. Ex; e^0=1

But we also know that eulers number (e=2.718...) to the power of i (√-1) times 2∏ equals one; e^i2∏=1

So we have to equations that both equals 1. That means that e^0=e^i2∏ and that;

0=i2∏

Is this right? (it can't be?)
 
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johann1301 said:
We know that any number to the power of zero equals one. Ex; e^0=1

But we also know that eulers number (e=2.718...) to the power of i (√-1) times 2∏ equals one; e^i2∏=1

So we have to equations that both equals 1. That means that e^0=e^i2∏ and that;

0=i2∏

Is this right? (it can't be?)


Take a wild guess...:>)

What is true is: any non-zero number to the power of zero is one, and [itex]\,e^{2n\pi i}=1\,[/itex] for any integer n...

DonAntonio
 


Ok, I am in shock!

If i continue then;

0=i2pie ⇔ 0/2pie=i ⇔ 0=i !

If this is true, doesn't it imply that i can f.ex write; 0=0+ai where a is any real number?

and f. ex 3=3+4i. (or 3=3+ai where a is any real number)

this must be true if 0=i2pie is true.

(I think?)

feel free to disagree, honestly;)
 
Last edited:


and that one can write b=ai where a and be are two real numbers that doesn't necessary equal!

f.ex 3=298i

?
 


johann1301 said:
We know that any number to the power of zero equals one. Ex; e^0=1

But we also know that eulers number (e=2.718...) to the power of i (√-1) times 2∏ equals one; e^i2∏=1

So we have to equations that both equals 1. That means that e^0=e^i2∏ and that;

0=i2∏

Is this right? (it can't be?)

You are working under the assumption that ea = eb implies that a = b for all complex numbers a and b. Can you prove this assertion? If not, can you prove that it is false?
Consider the fact that cos(2Pi) = cos(0). Does this imply that 2Pi = 0? If not, why not? Is this property applicable to your case?
 


Is -1=1 just because (-1)^2=1^2?
 


arildno said:
Is -1=1 just because (-1)^2=1^2?

That wasn't how i taught of it;

If one can say that 0=i it must be because when "you are" at any point ON the imaginary axis, then the value on the real axis will always be zero.

Just as when you say the same in a typical graph with x- and y-axis. When "you are" at any point on the y-axis, then x=0.
 


You need to revise your complex numbers . e^z (with z complex) is not injective.
 


dextercioby said:
You need to revise your complex numbers . e^z (with z complex) is not injective.

Translating for the OP, who may not have any knowledge of set theory: Given two complex numbers w and z, ez = ew does not imply that z = w.
 
  • #10


The complex exponential is periodic function with period 2pi. So when two complex exponential are equal, that means the exponents are equal up to an additive constant of form n2pi, where n is integer.
In mathematical terms:
e^ix = e^iy => x = y + n2pi
 
  • #11


Dead Boss said:
The complex exponential is periodic function with period 2pi. So when two complex exponential are equal, that means the exponents are equal up to an additive constant of form n2pi, where n is integer.
In mathematical terms:
e^ix = e^iy => x = y + n2pi



Well, in fact it is [tex]e^{z_1}=e^{z_2}\Longleftrightarrow z_1=z_2+2n\pi i\,\,,\,\,z_1,z_2\in\mathbb{C}[/tex] no need to add that "i" in th exponent

DonAntonio
 

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