Re: Sum of all natural numbers = -1/12?

2014-01-30 Thread Bruno Marchal
On 29 Jan 2014, at 22:28, Russell Standish wrote: As someone pointed out, it requires a non-standard definition of convergence, as these series are non-convergent according to the usual Cauchy definition. IIRC, it may be Abel summation? I remember Abel summation being mentioned during my

Re: Sum of all natural numbers = -1/12?

2014-01-30 Thread Bruno Marchal
On 30 Jan 2014, at 00:07, LizR wrote: On 30 January 2014 12:11, Russell Standish li...@hpcoders.com.au wrote: Yes. Pity the poor blighters at high school if someone tried to teach them this stuff. I remember someone once showed me the definition of continuity in year 11 (with all the upside

Re: Sum of all natural numbers = -1/12?

2014-01-30 Thread LizR
On 31 January 2014 04:43, Bruno Marchal marc...@ulb.ac.be wrote: On 30 Jan 2014, at 00:07, LizR wrote: On 30 January 2014 12:11, Russell Standish li...@hpcoders.com.au wrote: Yes. Pity the poor blighters at high school if someone tried to teach them this stuff. I remember someone once

Re: Sum of all natural numbers = -1/12?

2014-01-29 Thread LizR
OK... thanks, I should have guesses it was the zeta function :D Anyway, I showed this proof to my 15 year old son and he soon put me right on why 1-1+1-1+1-1+1... is indeed 1/2. call the series 1-1+1-1+1... S then 1-S = 1 - (1-1+1-1+1-1+1...) = 1-1+1-1+1-1... = S S=1-S, so S=1/2 (which is, I

Re: Sum of all natural numbers = -1/12?

2014-01-29 Thread Telmo Menezes
On Wed, Jan 29, 2014 at 9:56 PM, LizR lizj...@gmail.com wrote: OK... thanks, I should have guesses it was the zeta function :D Anyway, I showed this proof to my 15 year old son and he soon put me right on why 1-1+1-1+1-1+1... is indeed 1/2. call the series 1-1+1-1+1... S then 1-S = 1 -

Re: Sum of all natural numbers = -1/12?

2014-01-29 Thread Russell Standish
As someone pointed out, it requires a non-standard definition of convergence, as these series are non-convergent according to the usual Cauchy definition. IIRC, it may be Abel summation? I remember Abel summation being mentioned during my elementary analysis course, but nobody seemed to

Re: Sum of all natural numbers = -1/12?

2014-01-29 Thread LizR
That's basically how the guys in the video summed it. On 30 January 2014 10:11, Telmo Menezes te...@telmomenezes.com wrote: I've noticed something (maybe silly, maybe trivial?). Let's say: S(0) = 1 = 1 S(1) = 1 - 1 = 0 S(2) = 1 - 1 + 1 = 1 S(3) = 1 - 1 +

Re: Sum of all natural numbers = -1/12?

2014-01-29 Thread LizR
On 30 January 2014 10:28, Russell Standish li...@hpcoders.com.au wrote: As someone pointed out, it requires a non-standard definition of convergence, as these series are non-convergent according to the usual Cauchy definition. Surely they are non convergent full stop? But even so I can't

Re: Sum of all natural numbers = -1/12?

2014-01-29 Thread Russell Standish
I just went upstairs and dug out my copy of Marsden's Elementary Classical Analysis (don't you love the way advanced maths books are elementary this, or elementary that - except for my favourite, Mathematics Made Difficult, by Linderholm). It's the concept of Cesaro 1-summability that I was dimly

Re: Sum of all natural numbers = -1/12?

2014-01-29 Thread LizR
On 30 January 2014 11:56, Russell Standish li...@hpcoders.com.au wrote: I just went upstairs and dug out my copy of Marsden's Elementary Classical Analysis (don't you love the way advanced maths books are elementary this, or elementary that - except for my favourite, Mathematics Made

Re: Sum of all natural numbers = -1/12?

2014-01-29 Thread LizR
On 30 January 2014 11:56, Russell Standish li...@hpcoders.com.au wrote: It's the concept of Cesaro 1-summability that I was dimly recalling (page 125), but on page 126, it appears the same result is achieved by Abel summability, which is more general. Is Abel the person after whom Abelian

Re: Sum of all natural numbers = -1/12?

2014-01-29 Thread Russell Standish
On Thu, Jan 30, 2014 at 11:57:12AM +1300, LizR wrote: On 30 January 2014 11:56, Russell Standish li...@hpcoders.com.au wrote: It's the concept of Cesaro 1-summability that I was dimly recalling (page 125), but on page 126, it appears the same result is achieved by Abel summability,

Re: Sum of all natural numbers = -1/12?

2014-01-29 Thread Russell Standish
On Thu, Jan 30, 2014 at 11:53:31AM +1300, LizR wrote: If I ever write a book on the behaviour of birds native to the Antarctic, I must call it Elementary penguin singing hare krishna I might need an explanation of this. My cryptic crossword solver moduler has just blown a fuse. --

Re: Sum of all natural numbers = -1/12?

2014-01-29 Thread LizR
On 30 January 2014 12:11, Russell Standish li...@hpcoders.com.au wrote: Yes. Pity the poor blighters at high school if someone tried to teach them this stuff. I remember someone once showed me the definition of continuity in year 11 (with all the upside down As and back to frount Es), and it

Re: Sum of all natural numbers = -1/12?

2014-01-29 Thread LizR
On 30 January 2014 12:12, Russell Standish li...@hpcoders.com.au wrote: On Thu, Jan 30, 2014 at 11:53:31AM +1300, LizR wrote: If I ever write a book on the behaviour of birds native to the Antarctic, I must call it Elementary penguin singing hare krishna I might need an explanation of

Re: Sum of all natural numbers = -1/12?

2014-01-29 Thread Russell Standish
On Thu, Jan 30, 2014 at 12:07:08PM +1300, LizR wrote: On 30 January 2014 12:11, Russell Standish li...@hpcoders.com.au wrote: Yes. Pity the poor blighters at high school if someone tried to teach them this stuff. I remember someone once showed me the definition of continuity in year 11

Re: Sum of all natural numbers = -1/12?

2014-01-29 Thread LizR
On 30 January 2014 12:34, Russell Standish li...@hpcoders.com.au wrote: On Thu, Jan 30, 2014 at 12:07:08PM +1300, LizR wrote: On 30 January 2014 12:11, Russell Standish li...@hpcoders.com.au wrote: Yes. Pity the poor blighters at high school if someone tried to teach them this stuff.

Re: Sum of all natural numbers = -1/12?

2014-01-29 Thread Jesse Mazer
I think the problem is that for non-converging series, there are multiple similar tricks you could do that would give different answers...for example: S = 1-1+1-1+1-1... -1*S = -1+1-1+1-1+1... For a finite or converging series, the order of the summation doesn't affect the final sum, so if in

Re: Sum of all natural numbers = -1/12?

2014-01-29 Thread Jesse Mazer
On Wed, Jan 29, 2014 at 6:39 PM, LizR lizj...@gmail.com wrote: On 30 January 2014 12:34, Russell Standish li...@hpcoders.com.au wrote: On Thu, Jan 30, 2014 at 12:07:08PM +1300, LizR wrote: On 30 January 2014 12:11, Russell Standish li...@hpcoders.com.au wrote: Yes. Pity the poor

Re: Sum of all natural numbers = -1/12?

2014-01-29 Thread LizR
On 30 January 2014 12:45, Jesse Mazer laserma...@gmail.com wrote: I think the problem is that for non-converging series, there are multiple similar tricks you could do that would give different answers...for example: S = 1-1+1-1+1-1... -1*S = -1+1-1+1-1+1... For a finite or converging

Re: Sum of all natural numbers = -1/12?

2014-01-29 Thread LizR
On 30 January 2014 12:48, Jesse Mazer laserma...@gmail.com wrote: On Wed, Jan 29, 2014 at 6:39 PM, LizR lizj...@gmail.com wrote: On 30 January 2014 12:34, Russell Standish li...@hpcoders.com.au wrote: On Thu, Jan 30, 2014 at 12:07:08PM +1300, LizR wrote: On 30 January 2014 12:11, Russell

Re: Sum of all natural numbers = -1/12?

2014-01-19 Thread Bruno Marchal
On 18 Jan 2014, at 02:27, LizR wrote: The demonstration that the sum of the positive integers is -1/12 relies on the assumption that the sum of 1 + 1 - 1 + 1 - 1 + 1 - 1 + 1 - 1 + 1 - 1 + 1 - 1 + 1 - 1 + 1 - 1 is 1/2 However that is by no means certain. It is 1 - 1 + 1 - 1 +

Re: Sum of all natural numbers = -1/12?

2014-01-18 Thread LizR
It was that wonderful Indian mathematician Srinivasa Ramanujan who first came up with the proof in 1913. https://en.wikipedia.org/wiki/Ramanujan_summation -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and

Re: Sum of all natural numbers = -1/12?

2014-01-18 Thread Bruno Marchal
Alberto, What is amusing is that Ramanujan said this (that 1+2+3+... = -1/12) in a letter to find a job in England, just to illustrate that he was not bad in computing. He was of course considered as crackpot until the letter was given to Hardy, who recognized immediately the genius.

Re: Sum of all natural numbers = -1/12?

2014-01-18 Thread Alberto G. Corona
Amazing. That means that there are much left to discover in math. And also note that: 1/12 = 2/24 and 24= flip 42 for some well known flip : N - N ;) 2014/1/18, Bruno Marchal marc...@ulb.ac.be: Alberto, What is amusing is that Ramanujan said this (that 1+2+3+... = -1/12) in a letter to

Re: Sum of all natural numbers = -1/12?

2014-01-17 Thread Alberto G. Corona
That is absolutely wrong. Everyone know that the result is 42 ;) 2014/1/17, Craig Weinberg whatsons...@gmail.com: http://sploid.gizmodo.com/the-sum-of-1-2-3-4-5-until-infinity-is-so-1503066071 -- You received this message because you are subscribed to the Google Groups Everything List group.

Re: Sum of all natural numbers = -1/12?

2014-01-17 Thread Alberto G. Corona
http://en.wikipedia.org/wiki/Deep_Thought_(The_Hitchhiker%27s_Guide_to_the_Galaxy)#Deep_Thought 2014/1/17, Alberto G. Corona agocor...@gmail.com: That is absolutely wrong. Everyone know that the result is 42 ;) 2014/1/17, Craig Weinberg whatsons...@gmail.com:

Re: Sum of all natural numbers = -1/12?

2014-01-17 Thread Craig Weinberg
Adams wasn't the only one to figure it out... http://www.amazon.com/Prayer-Kabbalist-42-Letter-Name-God/dp/1571895752 :) I forget how many times you have to say DEMOGORGON before he is summoned. On Friday, January 17, 2014 12:45:22 PM UTC-5, Alberto G.Corona wrote:

Re: Sum of all natural numbers = -1/12?

2014-01-17 Thread Alberto G. Corona
Google can not lie you: https://www.google.es/search?q=the+answer+to+life%2C+universe+and+everythingoq=the+answer+to+life%2C+universe+and+everythingaqs=chrome..69i57j0l5.402j0j9sourceid=chromeespv=210es_sm=93ie=UTF-8#q=answer+to+life+the+universe+and+everything 2014/1/17, Craig Weinberg

Re: Sum of all natural numbers = -1/12?

2014-01-17 Thread LizR
The demonstration that the sum of the positive integers is -1/12 relies on the assumption that the sum of 1 + 1 - 1 + 1 - 1 + 1 - 1 + 1 - 1 + 1 - 1 + 1 - 1 + 1 - 1 + 1 - 1 is 1/2 However that is by no means certain. The sum could be undefined, in which case the proof simply fails. Or it

Re: Sum of all natural numbers = -1/12?

2014-01-17 Thread Craig Weinberg
That's pretty much what I thought. The idea that the sum of such a series *equals* 1/2 I think is only one way to make sense of it. Who says that a rational number is even an option? What if +1 and -1 are absolute, like 'moving' and 'static'. There is no 1/2 moving. Still, it's interesting to