Is 1 = 0.999... ? Really?

Yes, but isn’t that just a practical restriction? We can’t write infinite decimal places, granted. But we know that if .33333… continued on infinitely, it would equal 1/3, right? There’s no contradiction saying we can’t completely write it out and saying that an infinite string would equal 1/3. We don’t need to know the final end of pi to solve equations in terms of pi. We don’t need to know the final end of sqrt(2) to know that squrt(2)^2=2. What’s the problem?

Carleas,

The problem is , that at present accuracy of utilization, there is no problem. But at the rate of acceleration of technological progress, and future need for exponential need for more and more accuracy, the requirements of carrying the decimal much farther may carry the decimal point accordingly.

Therefore, the conceptual application may for a very long time trump the empirical approximations.
The applications may trail the mathematical requirements for
reasons of having to do with expected or , projected requirememts.

That is false.
n/infinity = undefined infinitesimal.

The fact that they converge at different rates tells you that one is a lesser cardinality than the other (albeit fractional).

Each and every 1/(2^n) that is summed into the accumulation is less than each 9/(10^n), thus there is no possibility for the second sum to ever accumulate as much as the first - infinitely.

Just after the first 10 summations, we have:

  1. 0.9999999999
  2. 0.9990234375

And it can never catch up.

Plus we have the fact that more than half of the trailing digits for every partial sum throughout the entire infinite set are less than 9, with no opportunity for any digit to ever be more than 9 (leading to an infinite list of digits that are less than 9 as a part of the infinite set of digits). If merely one out of the entire infinite set of digits is less than 9, the entire sum must be less than the sum of all digits being a 9. The fact that the series of digits never ends means that the trailing half of less-then-9 digits are ALWAYS there. Thus the entire infinite series represents a number than is necessarily less than the first series.

No. It is a restriction in concept too. It is saying that there will always and forever be a remaining amount that has not been included. The ellipsis symbol means that an end result CANNOT be reached and thus IS NOT available in this digital form.

"Infinitely"does NOT mean that you get to an end “at infinity”, because there is no “at infinity”.
It means there is no end to finally reach the conclusion, thus there is always an infinitesimal remaining amount.

That is true for WHY it shouldn’t be taught incorrectly (as it currently is). The same is true for a great deal of physics that is good enough in a practical sense (just as thinking that the Earth is flat), but isn’t exactly right and thus will lead to conflict, confusion, and perhaps danger in the future. Why teach a lie? What is being gained?

But for any x such that
x = sum from 1 to n of 9/(10[1]n[/i])

there’s an m such that

1 > sum of from 1 to m of 1/(2[2]m[/i]) > x

That’s why the sum of each infinite series is 1: for any (standard) real number x, there is an m such that the sum s from 1 to m is between 1 and x. The only way that that can be true is if the sum of the infinite series is equal to 1.

Again, it sounds like you’re talking about a limit. The ellipsis doesn’t mean we’re waiting for it, hoping that eventually enough decimal places will build up underneath it that we can wave our hands and move on. The value in every decimal place is specifically and statically defined by the ellipsis (or r or bar or several other conventional shorthands for ‘like this infinitely’).

Just like we cross an infinite number of real numbers when we count 1, 2, 3…, we imply an infinite number of decimal places with .333… They’re all there, they aren’t reaching for anything. They’re all already full of 3s.

It seems as though you want to imply that at least one of them is not a 3, but that’s not the case. They are all 3s, so there is no infinitesimal amount remaining.


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I can’t tell if that even makes sense.
For each sum from 1 to n for series (1), S1n, there is an m such that: 1 > S2m > S1n

If I’m reading that right, it is false. S1n > S2m, for n=m, always. And for n<>m, it is irrelevant.

Of course I am talking about the limit. And the ellipsis is telling you that the string of 9s cannot ever reach that limit. It really isn’t merely a shorthand issue. The shorthand is short for expressing an infinite series, but it is NOT shorthand for “When it finally gets to infinity” - and that is how you are reading it.

There is no “getting to infinity” even in concept.

No. I am saying that there is ALWAYS more 3s required to get to the limit. There CANNOT ever be enough 3s, even in concept because in concept there is no end to infinite (there is no “infinity” to be reached). It is impossible to have enough 3s.


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It does catch up and where? In infinity.

If 256/infinite is the whole equation then the result is exactly 0.
To not be 0 it would have to be multiplied by infinite.
Then the result could still be 0, it could be infinite or it could be any Real value like 5.
Such a case requires a different look at the equation at hand and then it may be possible to determine the value.

Some basic rules which are always true -
infinite/infinite = not defined (could be anything)
(infinite^2)/infinite = infinite
infinite/(infinite^2) = 0
infinite*0 = not defined (could be anything)

Or let’s take integral calculus - Here infinitesimally small elements are summed up infinitely often and the result can be calculated. It will be 0, or infinite or a defined value, depending on the equation (function).

If the equation is simply 17.7898/infinite then the result is exactly 0.

What I just wrote down is basic bitch math. If you have an issue with it then you have an issue with the consensus in mathematics and they are pretty conservative when it comes to their definitions and how all the various operations and theories are interlinked.

You have it backward. Every 1/(2^n) term is larger than the 9/(10^n) term except for the very first one. So it does “catch up”.

Unfortunately for the bluster of this paragraph, I think James is correct on this point. As I understand it, 1/infinity is not a proper mathematical formula, because infinity is not a number. You can take the limit of 1/x as x goes to infinity, and that’s zero, but it’s improper to treat infinity as a number and plug it in directly for x.

Moreover, I don’t think it’s obvious that the limit x^2/x as x goes to infinity is infinity. My understanding is that, for a countable infinity, a plane that countably infinite in two dimensions has the same size as a countably infinite 1 dimensional line. Each point in the coordinate plane can be uniquely assigned to exactly one number on the infinite line. That means that there are an equal number of points on the line and the plane.

I’m saying that for any finite sum of the one series, there is a finite sum of the other series that is closer to 1. Even if one series will always lag behind, it will also always have a finite sum that is closer to 1 than any finite sum of the other series. For that reason, it can’t be said that one infinite sum is strictly larger than the other. The speed at which they converge does not seem relevant to the value of the infinite sum.

To put it another way, if we plotted the values of each, even though the curves would be different, the area under each curve would be exactly 1.

I don’t see the distinction you’re trying to make here.

But there are infinite 3s, there can’t be more 3s (again, dealing with a countably infinite string of decimal places). There doesn’t need to be an end, and in fact an end would make the string finite and so less than 1/3. But an infinite string has all the decimal places it needs: all of them.

It has been a while but I remember that equivalent transformations were okay when dealing with lim x->infinite functions.

So for example: f(x)= x^2/x => f(x)= x , (division by x, which is a transformation that should be fine)
and
lim x->infinite f(x)= x = infinite

Or f(x)= (x-1)/(x+1) => f(x)= (1)-(1/x)) / (1+(1/x)) (division by x, which should be fine as long as x is not 0)

and so lim x->infinite f(x)= (x-1)/(x+1) = lim x->infinite f(x)= (1)-(1/x)) / (1+(1/x)) = 1

Whether or not this is trivial to show/prove I don’t know (anymore), but it’s standard procedure.

The shorthand is for infinite series but not for getting to 1. The shorthand is particularly a mathematical notation, and not based on assumptions of notating an infinite function limited by 1 , but on assumption of there being such a limit. (Since the limit by
definition is qualified by an infinite function).

There is no “in infinity” just as there is no “at infinity”.

Infinite is a quality, not a quantity. The quality is that of being “endless”.
What you are saying is:
1/endless = 0
256/endless = 0

“endless” isn’t a number that can be divided into anything, nor is “infinity” because it is not a quantity.

We aren’t “basic bitches” here. We don’t give credit for being right to the world merely because was there before we were. And this isn’t high school. We are examining analytical perfection, not practical applications taught to the world in general.

Ack! Your right. I was thinking of the partial sums, not the individual terms … My bad

It still doesn’t catch up. It just isn’t so obvious.

That’s irrelevant. “Each runner eventually gains more distance than half as much as the other.” Well, yeah, so what.

The “area under the curve” IS the “summation”. They are the same thing. So you are just repeating your false assertion with different words.

.
That … that … that is the issue and problem.
It is YOU, YOU, YOU who are presuming a destination of “enough 3s” to finally equal 1/3. That point does not exist. There is no “enough 3s” to satisfy the stipulation. “Endless” or “infinitely” MEANS that there is no satisfied point to get to. There is no “infinity” or end to “endless”.

The convergence must either be satisfied or not, right?

If it could be satisfied, it would equal 1/3 (in this case).
But the ellipsis is conveying that the series cannot be satisfied - ever.

True.

You are right about that: infinite divided by 11.599999999…. = still infinite
and because it’s not a number, 1/infinite = any number divided by infinite = zero.

Right again, more like advanced bitching.
You seem to use the term world in the sense of society or people at large.
So, what have you learned from examining analytical perfection, found any chinks? Or poles? The 1?

An infinitesimally small element has no size, it’s not defined.
In a math-world built around abstractions, that’s what nothing is - it’s not defined, a cypher.

Let’s say two different series are moving not towards a Real number but towards infinity, at different rates though -
Would you say they eventually end up at different infinities?
Because that would be the inversion of such a difference between two infinitesimally small nothings.

0.99999…. + 0 = 1

I find that your thinking here is very common though. Not gonna say it’s ‘basic bitch’ because that sounds negative to your ears.
You seem to think in a way like - “Well, there is some number and that number gets smaller and smaller but it doesn’t get reduced to zero, in no step, thus, at the end, there must still be some-thing.” - True, except for infinite.

Nope. It’s still merely infinitesimal (which is also not a number).

Yep.
Rational Metaphysics: Affectance Ontology – The One.

It has size, just not a specific size other than merely too small to measure.
infinitesimal = 1/infinite

Certainly. And that is called different “cardinalities”.
And 1 divided by each of those is equally a different infinitesimal.

I find your thinking to be quite common. “There at infinity, it finally gets to where its going”. True except that there is no “at infinity”.

Cardinality of different number spaces?
I’m talking about something like your proposed two series, both in the Real number space.
Like, do you think
lim x->infinite f(x)= 9*x
a different infinite (the function value) than
lim x->infinite f(x)= x
?

I don’t think so but then again maybe a google search can find me another theory for some other dimensional constructed number space.

As for absolutes, they can be found in the thinking of man.

Since when is not being able to measure something an issue for mathematics?
Anyway, I’ve looked it up on wikipedia where the first introductory sentence talks about how it’s too small to measure. Historically that’s based on physicists or an analogy to a physical problem.

I guess, the nice thing about things which are not defined, it leaves room for your own creations.

And something doesn’t have to get to infinity to identify what it is converging towards. Math is not reality, it’s an idealised abstraction. Within it absolutes can be and are defined. Zero.

You said two “infinites”.

Again, you display two infinites, not two infinite strings of decimal digits.
Both of those functions are infinite, but yes, the first is a greater infinite than the second.
And if you divide each of those into 1, you will get two different sized infinitesimals.

Our two infinite decimal strings are:

  1. Σ[9/(10^n)]
  2. Σ[1/(2^n)]

Search this

We aren’t debating the existence of absolutes in nature, either. In man’s mind, there are fantasy concepts and there are rational concepts. “Infinity” is a fantasy concept. It is actually an oxymoron in that the word “infinite” means “no end” while the word “infinity” implies where infinite ends: “To infinity and beyond!”

The concept of infinitesimal came before it was an issue in math. When math derived a series that grew infinitely small, they merely used the common sense word for it, “infinitesimal”. Since “infinite” had no specific quantity, neither would “infinitesimal”.

We all know what it is converging toward. The debate is about what it is “equal to”.
And the reality is that it isn’t a number either, so it really isn’t equal to its limit, which is a number.

Carleas,

Do you accept that there are different sizes of infinities (aka “varied cardinalities”)?

At the most basic level, “.999… = 1” is a meaningless string of symbols.

It becomes a valid logical inference as soon as you define what the symbols mean and give a precise definition of the limit of a sequence of real numbers. Once you do that, the validity of .999… = 1 is beyond dispute. Given a set of inference rules and the standard mathematical axioms and definitions coded as strings, a computer could verify that “.999… = 1” is an output of the system.

We casually say .999… = 1 is “true,” or we just say .999… = 1. But if we are being formal, all we mean is that it’s a valid theorem of the theory of the real numbers.

As an analogy take any formal game like chess. Given the rules of chess, we can prove the “theorem” that in any legal position, a bishop must be standing on a square of the same color as the square it started on. You may not like chess. You may feel that chess is somehow wrong, or that it does not properly embody the ideas that you have about chess. That’s perfectly ok.

Even so you must agree that one the rules are fixed, the “bishop theorem” is nothing more than a logical application of the rules of chess, wrong as you think they are. Likewise, .999… = 1 is a logical consequence of the rules of mathematics. You could say that the string of symbols “.999… = 1” is a legal position in the game of math.

Math makes no claims as to truth or meaning outside of that context. Math doesn’t claim it’s true about the physical world or that it’s philosophically correct. Some particular mathematicians may make such claims, but when they do they’re acting as philosophers and not as mathematicians.

This quote from Arminius sums it up:

I quite agree, though I’d substitute “physically” for “logically,” since .999… = 1 is a purely logical consequence of the axioms of set theory and the precise definitions of “.999…”, “=”, and “1”.

James, you seem to be arguing against the math itself. And instead of using the standard definitions, you make up your own definitions. I just quoted one example above, but you’ve done this many times. An infinitesimal in math is defined as a quantity that is greater than 0, but less than 1/n for each of n = 1, 2, 3, … That’s the definition. That’s the only definition. That’s how you recognize an infinitesimal when you see one. That’s the definition of the infinitesimals in the hyperreals. The symbol “1/infinite” is undefined, it has no meaning at all. It’s just something you made up.

Of course by making up your own definitions you can win all your arguments. But you aren’t saying anything meaningful about math.

Here is the technical definition of the limit of a sequence of real numbers.

en.wikipedia.org/wiki/Limit_of_ … definition.

Once you understand what is the limit of a sequence of real numbers; then .999… = 1 is valid because .999… is defined as the limit of the sequence .9, ,99, .999, …, which is 1. And every symbol and every step in the proof is carefully and precisely defined such that a machine could verify the proof.

If you would take the trouble to learn the actual mathematics, you would be in a better position to credibly criticize it.

About time you showed up. And once again, starting off with the insults (as expected):

Quite the opposite is actually true.

If you would learn the exact details of the philosophy of numbers and mathematics, you would discover that the common professings are not actually true. And that is what this debate is about.

So you can leave your ad hoc effort to demean the opposition up your ass where it belongs with the other shitty presumptions.

Cogent arguments are all that counts. Stick with them, else you have already experienced where it will lead.

I hope you are referring to “0.999…” rather than “999…”.

You are preaching dogma. That is not the point here. You need to come up with a rigorous proof of your theory, not merely espouse what is supposed to be accepted. You are not on the religion forum any more.

Irrelevant and doesn’t really apply to what we are discussing.

That is the debate. I say that what you just said is not true and I have given 2 proofs as to why not. You need to:

  1. show how my proofs are flawed
  2. display your logic proof that concludes as you prefer.

Not at all. I am just speaking of a level above what you learned. My definitions are a common part of Hyperreal Numbers because they deal with infinities and infinitesimals, unlike standard reals that exclude them.

Infinity doesn’t exist in real numbers. The number line is infinite in length, but there is no “infinity” to be reached or discussed. A number sequence that is infinite in length cannot ever be satisfied and thus cannot ever be equal to its limit.

Sorry, but that is just silly on your part.
“1/n for n greater than every integer”
But that is magically different than:
“1 / infinite”
Never mind that “greater than every integer = infinite”. Let’s not look at that, else we would see through simple substitution that, indeed:
for n = (any number greater than every integer),
1 / (any number greater than every integer) = 1 / infinite.
#-o

Yeah well, if you would bother to carefully examine the Wiki article you will see that they are defining what a “LIMIT” is. They are NOT proving that the infinite sum is equal to that limit. They even write it as “the limit as x goes to infinity” equals whatever, not that the sum equals whatever.

Wiki does have an article on whether “1.00 = 0.999…”, but my argument (with proofs included) claim otherwise as I point out their flaws as well as provide contrary proofs.

You might want to start working on doing the same if you want to do anything other than ad hoc your way through this.

The sum of an infinite series is defined as the limit of the sequence of partial sums.

This is about what I expected from you.

You got your wish. Have a nice evening.

Then you should have learned to not try the ad hoc, slip in an insult, game with me.

I don’t see anyone saying that the sum is the limit except on forums where presumption reigns.

Throughout the math world it is “The LIMIT of the Sum is equal to…”