Why is the prime counting function seemingly contradictory?

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Discussion Overview

The discussion revolves around the prime counting function and its properties, particularly in the context of differentiability and the use of distributions. Participants explore the implications of certain mathematical expressions and challenge each other's interpretations and reasoning.

Discussion Character

  • Debate/contested
  • Technical explanation
  • Mathematical reasoning

Main Points Raised

  • One participant presents an expression involving the prime counting function and suggests a paradox related to its differentiability.
  • Another participant questions the validity of the initial expression, indicating it does not make sense as written.
  • Some participants express skepticism about the differentiability of the prime counting function, suggesting it is a step function.
  • A participant introduces the concept of distributions and their relation to the prime counting function, referencing the Abel sum formula.
  • There is a discussion about the implications of dividing by distributions and the potential oddities that arise from such operations.
  • One participant critiques another's reasoning, suggesting that their claims about distributions and limits are not well-founded.
  • Another participant attempts to clarify their earlier statements regarding the manipulation of terms involving the prime counting function.
  • Concerns are raised about the misinterpretation of mathematical theorems, specifically Schwartz's theorem, and its application in this context.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the validity of the initial claims or the treatment of the prime counting function as a differentiable entity. Multiple competing views remain regarding the interpretation of distributions and their mathematical properties.

Contextual Notes

Limitations include unclear definitions and assumptions regarding the prime counting function and distributions, as well as unresolved mathematical steps in the arguments presented.

tpm
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An apparent paradox??

W have [tex]\int_{2}^{x} dt d\pi (t) t^{2} = \sum_{p \le x}p^{2}[/tex]

also for every prime p then [tex]\sigma _{2} (p) = 1+p^{2}[/tex]

by the definition of 'divisor function' of order 2

so [tex]\sum_{p \le x}p^{2}+ \pi (x) = \int_{2}^{x} dt d\pi (t) \sigma_{2}(t) = \sum_{p \le x} \sigma _{2} (p)[/tex]

since for every prime the divisor function has only 2 numbers 1 and p then differentiating to both sides we find:

[tex]d \pi (x) x^{2} = d \pi (x) \sigma_{2} (x)+ d \pi(x)[/tex]

which is completely absurd since we could remove the derivative of the prime counting function..i believe that perhaps a derivative of second order [tex]d^{2} \pi (x)[/tex] or a factor [tex]d \pi (x) d \pi (x)[/tex] should appear.
 
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tpm said:
[tex]\int_{2}^{x} dt d\pi (t) t^{2}[/tex]
This expression makes no sense. What did you mean to write?
 
Who knows. It is Jose (eljose), after all. I mean, who thinks that the 'prime counting function' is differentiable, apart from him?
 
was he banned from the forums?
 
He keeps making new accounts.
 
Since the 'Prime counting function' is an step function.then its derivative can be considered in the sense of 'distribution theory. and

[tex]\int_{2}^{x} dt d\pi (t) f(t)= \sum _{p \le x} f(p)[/tex]

integrating by parts you get the usual expression due to Abel sum formula.

[tex]\frac{d \pi (x) }{dx}= \sum_{p} \delta (x-p)[/tex]

here the sum is extended over all primes ..then could somebody respond to my 'paradox' ??
 
Let's start by calling it a 'mistake', not a paradox. Now, if you were to write it out clearly, using sentences, perhaps someone will attempt to work out what you're up to. One obvious thing is you want to 'remove the derivative of ...'. If by that you mean divide by a distribution that is almost always zero, you're bound to introduce oddities.
 
But..how the hell can you multiply or divide distributions?'..in fact:

[tex]\delta (x) \delta (x) = \frac{Sin(Nx)^{2}}{x^{2}}[/tex] (1)

hence, Schwartz theorem is false.. the same for any other distribution..let be a sucession of function then

[tex]f_{n} (x)g_{n} (x) \rightarrow S(x)U(x)[/tex] (2)

in both cases (1) and (2) you must take n-->oo as you can see the theorem by Schwartz is false.
 
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You're the person who wrote 'remove the...' without saying what you meant. Once more eljose, you're just ranting away and not making yourself at all intelligible.
 
  • #10
sorry in this case it was my fault by 'remove' i meant divide each term by [tex]d \pi (x)[/tex] instead i don't understand why this 'mess' about distributions..whenever you consider them as a limit of a certain sucession of function it's all clearer...don't you think also reading 'Calculus' by Spivak the notation is not new to prove Euler's sum formula they take:

[tex]\int _{0}^{\infty}f(x)d([x]) = \sum_{n=0}^{\infty} f(n)[/tex]
 
  • #11
So you want to divide out by a distribution and claim something? I see no reason to see why you should be able to do that. Not all properties commute with taking limits. In fact only in very special circumstances does anything commute with taking a limit. It is trivial to think of examples.

Take thr function f_n(x)=1/n for all x. The point wise limit is the zero function. The functions xf_n(x)-1 have roots for all n. That isn't true for xf(x)-1 for f the pointwise limit of f_n.

Just try reading some maths books with a little patience and try to understand them, before saying things like 'Schwarz's theorem is false'. What is the statement of the theorem, and why is it false?
 

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