What is the confusion surrounding complex numbers and their representation?

In summary, the speaker is familiar with complex numbers and their algebraic manipulations, but struggles to understand the concept of "iota" and its importance in solving equations involving cube roots or negative square roots. They question why we don't use other Greek letters, such as omega, in the same way. The speaker is also confused about the graphical representation of complex numbers and wonders if there are Argand diagrams in more than two dimensions. The expert explains that defining complex numbers without mentioning "iota" is possible, but it is not a good operation. There are other operations that can define complex numbers, but they all have their own limitations. The expert suggests reading more about the topic for a better understanding.
  • #1
Muhammad Ali
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I am familiar with complex nos. I know about their algebric manipulations, for example. But I could not understand the notion of ´iota´. I know that complex numbers are extremely essential for solving the equation involving cube roots or higher or negative square root of a number. I am also aware of their use in Quantum Physics and I, therefore, know about the importance of ´iota´. But I am unable to understand their working.
It appears to me that we have assume a greek letter for say finding the negative squareroot of number and thus everything is ok with it. If, for example, this is the way of finding the solutions then why don´t we take any real no divided by zero as equal to another Greek letter, say, omega.
Secondly, I am confused with the graphical representation of the complex numbers. We represent them using Argand Diagram and whenever I compare the Argand Diagram to the two dimensional real plane I don't find any difference. What is this nonsense?
Finally, Do we have Argand diagram in more than two dimension?
I am very irritated with these questions please help me out.
 
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  • #2
Muhammad Ali said:
If, for example, this is the way of finding the solutions then why don´t we take any real no divided by zero as equal to another Greek letter, say, omega.

who says that we don't? There are many places where do precisely this (as long as we are not dividing zero by zero).

Secondly, I am confused with the graphical representation of the complex numbers. We represent them using Argand Diagram and whenever I compare the Argand Diagram to the two dimensional real plane I don't find any difference. What is this nonsense?

this is a good observation, apart from the last sentence. The argand plane and the real plane are obviously different in one respect - one has axes labelled Re, and Im, and the other doesn't. Of course the complex numbers are in bijection with the real plane, which is what you're noticing. But pairs of real numbers (a,b) do not have any nice arithmetic defined on them a priori. For instance definin (a,b)*(c,d)=(ac,bd) is bad because you now have non-zero numbers that multiply to zero. The operation (a,b)*(c,d)=(ac-bd,ad+bc) is a good operation, and is precisely how one can define the complex numbers without mentioning i (and it is i, not iota. i has a dot above it, iota doesn't), but you'd only come to this after defining C=R.Note also that C is isomoprhic to R[x]/(x^2 +1), as well. this is the polynomials over R modulo the poly x^2 +1.
Finally, Do we have Argand diagram in more than two dimension?
I am very irritated with these questions please help me out.

there are several intepretations of this. I will go with: we have the quartenions (R^4 with a multiplication) but they are non-commutative. We have octonions, and sedonions (R^8 and R^16) but they are even more badly behaved. Apart from that any other multiplication operation will introduce zero divisors.

http://www.maths.bris.ac.uk/~maxmg/maths/introductory/complex.html

is something that explains all this in more detail
 
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  • #3


The confusion surrounding complex numbers and their representation can stem from a few different factors. First, the concept of "iota" or the imaginary unit can be difficult to grasp for those who are not familiar with it. It is essentially a number that, when squared, gives a negative result. This is necessary for solving certain equations and has practical applications in fields such as quantum physics.

However, the use of a Greek letter to represent this imaginary unit may seem arbitrary or confusing to some. It is important to remember that mathematics often uses symbols to represent concepts and operations, and "iota" is simply one of these symbols.

Another source of confusion may be the graphical representation of complex numbers using an Argand diagram. This diagram is essentially a two-dimensional graph with a real axis and an imaginary axis. The real numbers are represented along the horizontal axis and the imaginary numbers are represented along the vertical axis. This representation can be confusing because it may seem similar to a regular two-dimensional graph, but it is important to remember that the values on the vertical axis are not the same as regular numbers. They are multiples of the imaginary unit "iota".

It is also important to note that the Argand diagram is limited to two dimensions, as it is a representation of complex numbers on a two-dimensional plane. Higher dimensions can be used for other mathematical concepts, but they are not necessary for understanding complex numbers.

Overall, the confusion surrounding complex numbers and their representation can be overcome by gaining a deeper understanding of the concept of "iota" and the purpose of the Argand diagram. It may also be helpful to practice manipulating complex numbers algebraically and graphically to become more familiar with their properties and applications.
 

FAQ: What is the confusion surrounding complex numbers and their representation?

What are complex numbers?

Complex numbers are numbers that contain both a real part and an imaginary part. They are written in the form a + bi, where a is the real part and bi is the imaginary part. The imaginary part is represented by the letter i, which is equal to the square root of -1.

Why do we use complex numbers?

Complex numbers are used to represent quantities that cannot be expressed using only real numbers. They are especially useful in fields such as engineering, physics, and mathematics, where they are used to solve problems involving wave functions, electrical circuits, and other complex systems.

What is the difference between real and complex numbers?

The main difference between real and complex numbers is that real numbers contain only a real part, while complex numbers contain both a real and an imaginary part. Real numbers are used to represent quantities on a single number line, while complex numbers are represented on a two-dimensional plane known as the complex plane.

How do we perform mathematical operations with complex numbers?

To add or subtract complex numbers, we simply combine the real parts and the imaginary parts separately. To multiply complex numbers, we use the FOIL method, which stands for First, Outer, Inner, Last. To divide complex numbers, we use the conjugate of the denominator to eliminate the imaginary part.

What are the applications of complex numbers in real life?

Complex numbers have many applications in real life, including in electrical engineering, signal processing, and quantum mechanics. They are also used in fields such as economics, biology, and computer graphics. In everyday life, complex numbers are used to model and understand phenomena such as sound and light waves, electric circuits, and fluid dynamics.

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