Liste des Groupes | Revenir à s math |
On 11/6/2024 5:35 AM, WM wrote:The definitions of "functions", and "topologies",On 05.11.2024 18:25, Jim Burns wrote:>On 11/4/2024 12:32 PM, WM wrote:>>The intervals together cover a length of less than 3.>
The whole length is infinite.
Therefore there is plenty of space for
a point not in contact with any interval.
⎛ Assuming the covering intervals are translated
⎜ to where they are end.to.end.to.end,
⎜ there is plenty of space for
⎝ not.in.contact exterior points.
This plentiness does not change
when the intervals are translated.
⎛ When the intervals are end.to.end.to.end,
⎜ there are exterior points
⎝ a distance 10¹⁰⁰⁰⁰⁰ from any interval.
>
Are there points 10¹⁰⁰⁰⁰⁰ from any interval
when midpoints of intervals include
each of {...,-3,-2,-1,0,1,2,3,...} ?
>
Isn't that a plentiness which changes?
>>I mean 'exterior' in the topological sense.>
>
For a point x in the boundary ∂A of set A
each open set Oₓ which holds x
holds points in A and points not.in A
The intervals are closed with irrational endpoints.
'Exterior' seems like a good way to say
'not in contact'.
>
It seems to me that you have a better argument
with open intervals instead of closed,
but let them be closed, if you like.
>
Either way,
there are no points 10¹⁰⁰⁰⁰⁰ from any interval.
>>Each of {...,-3,-2,-1,0,1,2,3,...} is>
the midpoint of an interval.
There can't be any exterior point
a distance 1 from any interval.
>
There can't be any exterior point
a distance ⅟2 from any interval.
Nor ⅟3. Nor ⅟4. Nor any positive distance.
Nice try.
But there are points outside of intervals,
Are any of these points.outside
⅟2 from any interval? ⅟3? ⅟4?
>and they are closer to interval ends>
than to the interior, independent of
the configuration of the intervals.
Shouldn't I be pointing that out
to you?
>
If there is no point with more.than.⅟2
between it and any midpoint,
shouldn't there be fewer.than.no points
with more.than.⅟2 between it and
any closer endpoint?
>Note that>
only 3/oo of the points are inside.
Yes, less than 2³ᐟ²⋅ε
>
If the intervals were open,
all of that would be "inside"
in the interior of their union.
>
Of the rest,
none of it is more.than.⅟2 from any interval.
>>An exterior point which is not>
a positive distance from any interval
is not an exterior point.
Positive is what you can define,
Positive ℕ⁺ holds countable.to from.1
Positive ℚ⁺ holds ratios of elements of ℕ⁺
Positive ℝ⁺ holds points.between.splits of Q⁺
>but there is much more in smaller distance.>
Distances are positive or zero.
Two distinct points are a positive distance apart.
>Remember the infinitely many unit fractions>
within every eps > 0 that you can define.
For each of the infinitely.many unit fractions
there is no point a distance of that unit fraction
or more from any interval.
>>Therefore,>
in what is _almost_ your conclusion,
there are no exterior points.
There are 3/oo of all points exterior.
Did you intend to write "interior"?
>
An exterior point is in
an open interval holding no rational.
>
There are no
open intervals holding no rational.
>
There are no exterior points.
>
However,
there are boundary points.
All but 2³ᐟ²⋅ε are boundary points.
>>Instead, there are boundary points.>
For each x not.in the intervals,
each open set Oₓ which holds x
holds points in the intervals and
points not.in the intervals.
x is a boundary point.
The intervals are closed
We are only told
that Oₓ is an open set holding x
not that Oₓ is one of the ε.cover of ℚ
The question is whether x is a boundary point.
>>>The rationals are dense>
Yes.
Each multi.point interval [x,x′] holds
rationals.
>but the intervals are not.>
No.
Each multi.point interval [x,x′] holds
ε.cover intervals.
Therefore not all rationals are enumerated.
Explain why.
>
⎛ i/j ↦ kᵢⱼ = (i+j-1)(i+j-2)/2+i
⎜ k ↦ iₖ+jₖ = ⌈(2⋅k+¼)¹ᐟ²+½⌉
⎜ iₖ = k-(iₖ+jₖ-1)(iₖ+jₖ-2)/2
⎜ jₖ = (iₖ+jₖ)-iₖ
⎝ (iₖ+jₖ-1)(iₖ+jₖ-2)/2+iₖ = k>proves that>
the rationals are countable.
Contradiction.
It contradicts a non.empty exterior.
It doesn't contradict an almost.all boundary.
>Something of your theory is inconsistent.>
Your intuition is disturbed by
an almost.all boundary.
>
Disturbed intuitions and inconsistencies
are different.
>
>
Les messages affichés proviennent d'usenet.