Can This Seemingly Impossible Mathematical Series Be Solved?

  • Context: Graduate 
  • Thread starter Thread starter hagopbul
  • Start date Start date
  • Tags Tags
    Body
Click For Summary

Discussion Overview

The discussion revolves around a mathematical series that participants find challenging to solve. The series involves exponential functions and parameters that suggest a connection to physics, particularly in quantum mechanics or statistical mechanics contexts. Participants are seeking assistance in evaluating the convergence and potential solutions to the series.

Discussion Character

  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • One participant expresses frustration that the series appears impossible to solve, noting that even Mathematica fails to provide a solution.
  • Another participant suggests that the failure of Mathematica to solve the series may stem from the participant's dissatisfaction with its output rather than an actual inability to compute it.
  • A different participant argues that the terms of the series do not tend to zero, implying that the series does not converge, which raises questions about its existence.
  • There is a suggestion that simplifying the expression by reducing the number of brackets could facilitate understanding and solving the series.
  • One participant emphasizes that a series can exist without yielding a simple closed-form expression, challenging the notion that a solution must be straightforward.

Areas of Agreement / Disagreement

Participants exhibit disagreement regarding the solvability and convergence of the series. Some assert that the series does not converge, while others maintain that Mathematica's inability to solve it does not imply that it is unsolvable.

Contextual Notes

There are unresolved assumptions regarding the parameters involved in the series, particularly the notation "2 J K," which some participants interpret differently. The discussion also reflects a lack of consensus on the convergence of the series and the implications of its terms.

hagopbul
Messages
397
Reaction score
45
i have this problem and i am Trying to solve but it seems impossible so I need help
(even matmatica unable solve it )
seriesSum((2L+1)·(e^((((-((h)^(2)))·L·(L+1))/(2 J K)),L,0,∞)))

or :
seriesSum((2l+1)·(e^((((-((h)^(2)))·l·(l+1))/(2 J K)),l,0,∞)))

SO TRY YOUR LUKE HERE.:wink:
 
Physics news on Phys.org
hagopbul said:
i have this problem and i am Trying to solve but it seems impossible so I need help
(even matmatica unable solve it )
seriesSum((2L+1)·(e^((((-((h)^(2)))·L·(L+1))/(2 J K)),L,0,∞)))

or :
seriesSum((2l+1)·(e^((((-((h)^(2)))·l·(l+1))/(2 J K)),l,0,∞)))

SO TRY YOUR LUKE HERE.:wink:

I doubt very much that Mathematica can't do it. I suspect you just don't LIKE Mathematica's answer! Since your sum has several powers of L in the numerator, and only constants in the denominator, the individual terms do NOT go to 0 and so the sum does not converge. (I am assuming that you (2 J K) is just the product of three numbers and not some special notation you chose not to define!)
 
no you don't understand no body even Mathematica can do it i try
so i need help? even if you don't type 2*j*k
mathematica can't solve it.
 
I bet It would be much easier to do if you rewrote it for us without so many Brackets. I am not even going to bother trying to decipher that.
 
hagopbul said:
no you don't understand


No, *you* don't understand: since the terms do not tend to zero (according to HallsOfIvy), the sum does not exist. Further, even if it did exist, Mathematica would be able to tell you what it was, but not necessarily in a 'nice' closed formula involving the variables. You have made the common mistake of thinking that some thing is the answer if and only if it is a nice simple expression.
 

Similar threads

Replies
0
Views
2K
  • · Replies 4 ·
Replies
4
Views
3K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 3 ·
Replies
3
Views
4K
  • · Replies 3 ·
Replies
3
Views
1K
  • · Replies 4 ·
Replies
4
Views
2K
  • · Replies 3 ·
Replies
3
Views
4K
  • · Replies 0 ·
Replies
0
Views
2K