Question About Hilbert's Hotel

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If there’s no limit, then one can’t be ‘longer’ than the other. They’ll keep on going forever. The starting position doesn’t change anything when we’re dealing with the same type of infinite sets.

If we look at a finite subset of the infinite series, you would be correct. Like you notice, 1-10 has more elements in it than the set of odd numbers between 1-10. But, the infinite sets have no boundary so there can always be one more in the line - there can always be one more element. And these one more elements are in a one-to-one correspondence with each other. Neither set has more or less elements in them than each other.
 
Again, your “proof assumes that all infinities are equal”.
The infinity of the set of odd numbers and the infinity of the set of all natural numbers are equally both to a countable infinity. The number of real numbers is a greater infinity than the countable infinity of all natural numbers. It is not known with certainty if there is an infinity in between these two.
 
Again, your “proof assumes that all infinities are equal”. This is not hard to understand. If you have a straight line going forever north from where you are sitting, and another going south, both lines together are longer than just one, although all three are infinite. Most mathematicians don’t think about this like that because they are entrenched in there analytic world
I did not give a proof. I gave an explanation as to why your reasoning was flawed. I did not prove that they are the same size, only that your sets of numbers-less-than-n are always irrelevant to the infinite set’s size.
 
How exactly does Hilbert’s Hotel have to do with the Universe having a cause?
Basically put, it just attempts to show how ridiculous it would be to assume an infinity of causes. 🙂

I find it very reasonable, but then again, I’m not well-educated.
 
Basically put, it just attempts to show how ridiculous it would be to assume an infinity of causes. 🙂

I find it very reasonable, but then again, I’m not well-educated.
Unfortunately for your argument, convergent infinite series, converging and non-converging infinite series, infinite dimensional Hilbert spaces, and generally the concept of infinity is well accepted in mathematics and science.
 
I am not mistaken here.
Yes you are.
All the odd numbers have a one to one correspondence to all the even numbers, but there are left over the odd numbers of the second set.
You are correct for the finite sets that you are discussing. Some of the implicit assumptions you are making do not apply to infinite sets, hence your error.

I can put the three sets of positive integers, even integers and odd integers into a one-to-one correspondence, hence they all have the same cardinal number:
Code:
Integer    Even    Odd
-------    ----    ---
  1          2      1
  2          4      3
  3          6      5
  4          8      7
  5         10      9
            ...
  n         2n     2n-1
            ...
That list includes every integer, every even number and every odd number. None are missing, and all three sets have a one-to-one relationship.
You guys are trying to count to infinity.
No, we are deliberately avoiding that. We are putting the elements of two sets into a one-to-one correspondence, and so proving that the two sets have the same number of elements.
What else does a larger infinity mean than that there are more units in the larger one?
You need to study more about the Aleph numbers. It would also be useful to have a look at Cantor’s diagonal argument to prove the non-countability of the real numbers. That is a case where two sets cannot be put into a one-to-one correspondence and so there cannot be the same number of elements in each.

rossum
 
Here’s one way to prove my point: line up all the natural numbers going forever in one direction. Then side by side with it line up every multiple of ten. Both lines go on forever, but one is part of the other. YOU guys are taking the smaller set, taking away the gaps, and putting it side by side with the set of natural numbers, starting at one. But it is philosophically impossible to pull that line back like that! Imagine you are holding two ropes, both of which are going forward to infinity. It is not possible to pull one of them behind your back.

Proven: all odd numbers are not equal to all natural numbers
 
Here’s one way to prove my point: line up all the natural numbers going forever in one direction. Then side by side with it line up every multiple of ten. Both lines go on forever, but one is part of the other. YOU guys are taking the smaller set, taking away the gaps, and putting it side by side with the set of natural numbers, starting at one. But it is philosophically impossible to pull that line back like that! Imagine you are holding two ropes, both of which are going forward to infinity. It is not possible to pull one of them behind your back.

Proven: all odd numbers are not equal to all natural numbers
I mean this as charitable and graciously as possible. You are literally, not figuratively, talking nonsense. And the only thing the above proves is you don’t understand the concept of infinity. Or the basics of sets, perhaps. The set of natural numbers, and the set of multiples of ten are different sets that share elements. They’re not part of one another, except in perhaps a descriptive sense. If both sets are without limits, then there is no ‘smaller set’ to take gaps away from. Nor are there ‘gaps’ at all. The difference in elements aren’t ‘gaps’, they’re just different elements. The set of all natural numbers will always have another element. We’ll call this set George. So too will the set of every number divisible by one billion. We’ll call this set Larry. So let’s put the two sets together in a race, shall we? And see what happens.

Each set element is the same as one lap of a race track. George’s set is {1, 2, 3, 4, 5…N+1) So, in ten elements it will have gone 10.

Larry’s set is the element in George times one billion. So, in those same ten elements, Larry will also have gone 10. And for every element that George adds, Larry adds one too. George will NEVER have more elements than Larry. They will always have the exact same elements, when the sets are unbounded. These extra elements that George has are irrelevant to Larry - these elements aren’t in the set we’ve defined before even listing the elements.

You WOULD be correct if the sets are bounded. If we only cared about the first ten-billion elements, then yes. George will have more elements than Larry. But the sets, by definition, are infinite and without bounds. We’re not talking about distances, or weights, time spent, or counting on a number line. We’re just talking about elements in a set. 2, 3, 4, etc. aren’t elements Larry can have due to the definition of Larry. So they don’t matter. Every element George has will have a corresponding element in Larry. It’ll be like a ladder, where the rungs bridge the elements of the sets that are the side-parts. Every rung will connect an element of George to an element of Larry. Forever. There’ll be no holes, or gaps. There will always be a one-to-one correspondence between the elements of both sets. The sums of both sets will be infinite. The number of elements in both sets will be infinite. I don’t know how many more analogies I can spin to describe it.
 
Or, wait. Maybe I can. Imagine this rope you’re describing. Let’s remove the ‘gaps’ from Larry as you suggest. It ‘shortens’ Larry up, when compared to George. Except the sets are infinite. So that means the ropes are on a spool. We can keep tugging more and more rope out forever. So, Larry will be as long as George because we just pull more from the infinite spool. And for every inch of rope George has, Larry will also have an inch. Always. Forever.
 
You haven’t provided a demonstration to prove your position, so I am confident there is none. You are seeing infinity are a simple step by step, which it isn’t. Are numbers (imaginary or nor) what constitute the set of real numbers? Single mental things? Then line them up one by one with the natural numbers, starting by one, and your position makes it impossible for there to be larger and smaller infinities in any situation. The infinity of natural numbers goes in two directions. One direction lines with the odd numbers. But don’t forget about the other direction
 
Or, wait. Maybe I can. Imagine this rope you’re describing. Let’s remove the ‘gaps’ from Larry as you suggest. It ‘shortens’ Larry up, when compared to George. Except the sets are infinite. So that means the ropes are on a spool. We can keep tugging more and more rope out forever. So, Larry will be as long as George because we just pull more from the infinite spool. And for every inch of rope George has, Larry will also have an inch. Always. Forever.
Post 87 is a philosophical mathematical demonstration. But if doubting common assumptions is to hot for you, oh well
 
Post 87 is a philosophical mathematical demonstration. But if doubting common assumptions is to hot for you, oh well
Right, and the understanding of mathematics that underlies that demonstration is flawed. It also wasn’t a proof, as it was claimed to be. The conclusion was as faulty as the set-up. There aren’t any ‘gaps’, as I said. There’s nothing Larry is ‘missing’ that would make it smaller than George. They are the same size. That spool can always unspool some more and you’ll have a one-to-one correspondence.

What you’re doing is like doubting the common assumption that the sun is warm. Because you have a different understanding of what the sun means. An understanding that isn’t correct. What you’re saying is demonstratively wrong. The math and proofs are out there. Math and proofs that are consistent and coherent, and lead to good results in math and science.
 
Proven: all odd numbers are not equal to all natural numbers
It is true that the set of all odd numbers is not equal to the set of all natural numbers. All the even numbers are in the set of natural numbers, but no even number is in the set of odd numbers. However, this does not negate the fact that the set of odd numbers can be put in a 1-1 correspondence with the set of natural numbers. This is why they are both countably infinite sets. Although the two sets are not equal, they are both countably infinite.
 
Are numbers … what constitute the set of real numbers? … Then line them up one by one with the natural numbers, starting by one, and your position makes it impossible for there to be larger and smaller infinities in any situation.
The real numbers cannot be lined up in a 1-1 fashion with the natural numbers.
 
Right. The set of {a neuron, one cell from my gut flora, and an atom of hydrogen} is the same size as the set of {Mount Rushmore, Halley’s Comet, and Jupiter}
 
The infinity of natural numbers goes in two directions. One direction lines with the odd numbers. But don’t forget about the other direction
If you are going to include positive and negative integers, there is a way to line them up in one direction, and to include all of them:
0, 1, -1, 2 ,-1 ,3 ,-3, 4, -4, 5, -5, 6, -6, 7, -7,…
 
It is true that the set of all odd numbers is not equal to the set of all natural numbers. All the even numbers are in the set of natural numbers, but no even number is in the set of odd numbers. However, this does not negate the fact that the set of odd numbers can be put in a 1-1 correspondence with the set of natural numbers. This is why they are both countably infinite sets. Although the two sets are not equal, they are both countably infinite.
As I understand this, you have now changed your position.

If there is a 1-1 correspondence, than they are equal.

Your attempts at proving all {odd numbers} equal {all even numbers plus odd} fails in its method, because any infinity has units, and you can take those units and try to put them one to one with all the even plus odd numbers, and after ten correspondences say “and its goes on forever, they are the same!”. The gaps I was referring to was 1-9 for example.

Odd numbers are a part of odd plus even. You can’t ignore 2 4 6 8 and all the other gaps and pull the odd numbers back and say “look this set is infinite like the other”. Geometry and philosophy say no
 
As I understand this, you have now changed your position.

If there is a 1-1 correspondence, than they are equal.
1-1 correspondence does not mean equal. For example, the set {1,2,3,4} can be put into 1-1 correspondence with the set {2,4,6,8}. the two sets are not equal but they have the same number of elements. It is the number of elements that is equal in both sets. It is similar with countably infinite sets.
 
They are equal in the same number of elements they have, but not equal element-by-element. The former is what everyone thus-far has meant.
 
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