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/sci/ - Science & Math

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4223343 No.4223343 [Reply] [Original]

A friend told me he had seen his physics teacher prove that
1+1+1+...+1 (infinity time) equals -0.5.
WTF? Is it possible? Sounds like trolling, but I have to know.

>> No.4223348

http://en.wikipedia.org/wiki/1_%2B_2_%2B_3_%2B_4_%2B_%E2%80%A6

Ramanujam summation. It's a way of assigning values to divergent series that is useful for maths, but doesn't mean that it actually equals that

>> No.4223349

Suppose there is a x with x=1+1+1+...+1
x=1+(1+1+...+1)
x=1+x
0=1
His physics teacher is full of shit.

>> No.4223355

>>4223343
Of course this is wrong, but you can probably "prove" it using some power series outside of its radius of convergence. This is wrong, but if the reader doesn't know realize it you may fuck his mind.
I didn't find a power series that does the trick, though.

>> No.4223368

>>4223343
That would be a great logo for new visual studio.

>> No.4223377

>>4223368
Needs to be bluey/purply

>> No.4223387

http://en.wikipedia.org/wiki/1_%2B_1_%2B_1_%2B_1_%2B_%C2%B7_%C2%B7_%C2%B7

>> No.4223393

>1+2+3+4+... =/= -1/12
>but with renormalization, it is
>renormalization, not even once

>> No.4223398 [DELETED] 
File: 111 KB, 450x676, spider2.jpg [View same] [iqdb] [saucenao] [google]
4223398

Since there is no /edu/ board this is the only place I can ask.

I need downloable English test of the "General Question" variety. The ones where you have to provide the QUESTION to a given answer. Example:

sentence: Amy went to the grocer yesterday.
answer (given): She did it yesterday.
question (you have to do that in the test): When did Amy go to the grocer?

Anyone?

>> No.4223399

>>4223355
It almost works for sum(x^k, 1, infinity):
S(x) = x+x^2+x^3+...
S(x) * (1-x) = x+x^2+x^3+... - x^2-x^3-x^4-... = x
S(x) = x / (1-x)
-1+1-1+... = S(-1) = -0.5
It looks like the sum of OP. And it's wrong, because S is defined only for |x|<1.

>> No.4223400

>>4223343
Infinity is made-up bullshit.

>> No.4223401

>>4223398
Get the fuck out of here and die a slow and painful death.

>> No.4223404

>>4223400
How many rational numbers are there between 0 and 1?

>> No.4223417

There is a theorem stating that any non absolutely convergent series can be rearranged to sum to answer answer you like.

All it shows is that it's bullshit.

>> No.4223419

math cannot in infinity

>> No.4223422

>>4223404
0

>> No.4223423

>>4223404
At least you didn't say reals, since rational numbers aren't complete bullshit.

I don't know the answer, but I promise it is far less than all the particles in the universe.

>> No.4223425

>>4223422
And there goes a little more of my faith in the humankind.

>> No.4223433

>>4223423
So equation <div class="math"> x^2 = 2 [/moot] doesn't have any solutions?

And what makes you think that there's finite number of particles in the universe? What is a particle? Do we count electron sea (electrons with negative energy from Dirac's equation) as well? I'm pretty sure there's many of them. Infinitely many, one might say.

If not, what about the positrons then? Where do they come from?

Or are you just too fucking retarded to understand basic mathematics? Yeah, that will be it.

>> No.4223434

>>4223423
>I promise it is far less than all the particles in the universe
1/2, 1/3, 1/4, 1/5, 1/6...
please tell me you were trolling.

>> No.4223436

>>4223417
There's a theory that mathematicians will make up any bullshit idea they can manage if it will help them answer some other question. Infinity is like the dark matter of math. You can listen to all the kids here parrot, "Infinity is a concept, not a number!" It isn't even a concept. A concept of what? It isn't a process, it isn't a place... it sounds like some kind of faux-deep religious faggot waxing poetical about the soul, or divine beauty, or something.

You know mathematicians, when confronted with something like doubling the sphere, or oracular numbers, just shrug? "Numbers are so deep and mysterious..." No, they're not, not if you leave out all the bullshit like axiom of choice and infinity and stick purely with calculation. There are plenty of interesting things lying there without having to turn math into another fucking religion.

>> No.4223437

>>4223436
Go back to /prog/ you fagstrom.

>> No.4223438

>>4223436
And there goes all my faith in the humankind

>> No.4223449

>>4223433
> so this equation doesn't have any solutions
Not everything has a solution. This is just real life.

> And what makes you think that there's finite number of particles in the universe?
Because there is no such thing as infinity.

> Do we count electron sea (electrons with negative energy from Dirac's equation) as well?
You are welcome to *count* whatever you like. Emphasis on "count."

> Or are you just too fucking retarded to understand basic mathematics? Yeah, that will be it.
Typical defense of the religious apologist.

>> No.4223455

>>4223449
>provides framework that is unusable for solving problems
>word play
>ignoring uncomfortable remarks in arguments
>ad hominem

Typical conspiracy idiots blabber talk. I'm finished with you.

>> No.4223459

>>4223455
enjoy you're religion

>> No.4223460

>>4223436
>"Numbers are so deep and mysterious..."
Wat? I've never heard any mathematician say something remotely sounding like this. You obviously don't know what you're talking about. It's ok, many people can't into math. As long as you stay away from boards like /sci/.

>> No.4223472
File: 23 KB, 273x185, 1283293514691.jpg [View same] [iqdb] [saucenao] [google]
4223472

>>4223449

>> No.4223473

>>4223460
don't forget your eucharist while you suck down the load of your god infinity

>> No.4223488

>>4223449
>Because there is no such thing as infinity.
Who's having faith in something without proof? Maths are based on axioms, not dogmas. No one's ever said they were true. Many mathematicians have tried to question them, see what happens when you remove or add some.

Your belief that some axioms are irrevocably invalid, however, is based on faith. It is much closer to a religious way of thinking.

>> No.4223498

>>4223455
> provides framework that is unusable for solving problems
Dohohoho! If I don't accept the Lord Infinity into my heart, I lose all ability to calculate! But sir, it is not so, for no man can calculate "for ever," no process carries on "to infinity." I've got to stop to eat and sleep. Your mystery school religion which I have abandoned tries to claim otherwise, but apart from arcane writings, it looks to me like they still have to stop, too. They don't know pi to an infinite number of decimal places, even though they fervently believe it still has them.

Like last time this came up, and someone asked what the largest integer was. It's indeterminate. How would someone determine it? I mean actually determine it. Start with the successor function, and start applying it...

>> No.4223508

>>4223498
Either you are a troll or a extremely stupid person. But I'll still ask this: what is the result of 10 divide by 3? Is it 3.333... ?

>> No.4223527

>>4223508
Why wouldn't it be?