Transfinite Taylor series of exp(x) and of h(x)

In summary, the conversation discusses the possibility of extending the domain of exp(x) and h(x) to include values for x = Aleph(0). The idea of a "transfinite Taylor series" is brought up, but its definition and convergence are unclear. The Stirling approximation is mentioned in relation to evaluating a term of the series at Aleph(0), and the potential for a sum of Continuum terms. The topic of extending the Taylor series for h(x) is also mentioned, but no further details are provided.
  • #1
H Tomasz Grzybowski
12
0
Let h(h(x)) = exp(x), where h(⋅) is holomorphic in the whole ℂ plane.
I want an extension of the domain of exp(⋅) and of h(⋅) so that
we can find values of these functions for x = Aleph(0).
 
Physics news on Phys.org
  • #2
##\aleph_0^n = \aleph_0## so the "Maclaurin series" of ##\exp(\aleph_0)## will be ##\aleph_0##.
But this really isn't sensible since there is continuous measure on the space of transfinite cardinals. Or rather you will have to implement one to speak of limits of series and then your answer will depend on that choice.

Short of that you're using cardinal arithmetic. But notice the inconsistency in results. ##2^{\aleph_0}=\aleph_1## where we define the notation as a set of functions or power set, but
##e^{\aleph_0} \equiv 1 + \aleph_0 + (1/2!)\aleph_0^2 + \ldots = 1+\aleph_0 + \aleph_0 +\ldots = 1+\aleph_0\times\aleph_0 = \aleph_0##
 
  • Like
Likes FactChecker
  • #3
I agree with @jambaugh . Furthermore, unless someone has laid the groundwork regarding a metric, continuity, convergence, etc. that includes ##\aleph_0##, it is premature to consider the Taylor series. If such a groundwork and context has been laid, I am not aware of it.
 
  • #4
I clearly stated that I want TRANSFINITE Taylor series. When you look at a term omega+n of transfinite Taylor series, it follows from the Stirling formula that such a term evaluated at Aleph(0) wil have value Continuum. So will any transfinite sum not exceeding Continuum terms.
 
  • #5
The above refers to a transfinite Taylor series of exp(x). Taylor series of h(x) remains unknown.
 
  • #6
H Tomasz Grzybowski said:
I clearly stated that I want TRANSFINITE Taylor series. When you look at a term omega+n of transfinite Taylor series, it follows from the Stirling formula that such a term evaluated at Aleph(0) wil have value Continuum. So will any transfinite sum not exceeding Continuum terms.

You are speaking as if there is a standard definition of a Transfinite Taylor Series so would you be so kind to cite a reference. I've never seen such a definition (which is likely my failing but it certainly isn't a broadly known definition.) As to the Stirling formula I presume you're referring to the Stirling approximation of N! Is that correct? If so would you be so kind as to be a bit more explicit in your obvious "it follows from the Stirling formula" implication.

I'm familiar with the transfinite cardinals as well as the transfinite ordinals. And one can certainly define series in the abstract and the arithmetic thereof using series indexed by transfinite ordinals if you wish. You could even index with continuum variables and call them "integrals", and even index over function spaces if you pick some specific well ordering of that space. Basically the series are identified with the sequence of terms and one need not even insist on convergence.

But to speak of convergence in any context, namely to equate a series with a value in any sense you must apply some form of topology. What is the topology you are using when you speak of evaluating a Taylor series (transfinite or no) for the variable equaling a specific transfinite cardinal?
 
  • #7
Yes, by "Stirling formula" I mean the approximation of n!.
Regarding exp(Aleph(0)), each tansfinite term is equal to Continuum, so if there are no more than Continuum terms,
the sum equals Continuum.
My question is about possible extension of Taylor series of h(x), but as of now,
I do not know the usual Taylor series of it.
 

Related to Transfinite Taylor series of exp(x) and of h(x)

1. What is a transfinite Taylor series?

A transfinite Taylor series is an infinite series expansion of a mathematical function, such as exp(x) and h(x), using powers of x. However, unlike a traditional Taylor series which has a finite number of terms, a transfinite Taylor series has an infinite number of terms, extending to infinity.

2. How is a transfinite Taylor series different from a traditional Taylor series?

A traditional Taylor series has a finite number of terms, while a transfinite Taylor series has an infinite number of terms. This means that a transfinite Taylor series can provide a more accurate representation of a function, but it also requires more computational power to calculate.

3. Why is the use of transfinite Taylor series important in mathematical analysis?

Transfinite Taylor series allow for a more precise representation of functions, particularly those that are difficult to approximate with a traditional Taylor series. This can be useful in fields such as physics, engineering, and economics where accurate mathematical models are necessary.

4. Can transfinite Taylor series be used for any function?

No, transfinite Taylor series are only applicable for functions that are infinitely differentiable, meaning that they have an infinite number of derivatives. These include common functions such as polynomials, trigonometric functions, and exponential functions.

5. How are transfinite Taylor series related to the concept of infinity?

Transfinite Taylor series use the concept of infinity to represent an infinite number of terms in the series. However, it is important to note that while the series extends to infinity, it only provides an approximation of the original function and may not be an exact representation.

Similar threads

  • Introductory Physics Homework Help
Replies
5
Views
361
Replies
1
Views
220
Replies
2
Views
343
Replies
14
Views
3K
  • Set Theory, Logic, Probability, Statistics
Replies
8
Views
1K
  • Quantum Physics
Replies
3
Views
1K
Replies
2
Views
1K
  • Topology and Analysis
Replies
11
Views
1K
Replies
3
Views
757
Back
Top