Universe can't be infinite.

So what's really going on?

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TimeSeeker
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Re: Universe can't be infinite.

Post by TimeSeeker »

devans99 wrote: Tue Nov 27, 2018 2:20 pm Say I evaluate:

lim x->∞ 1/x ~> 0

the notation ~> preserves the fact that the expression approaches zero from above.

If I were to then use the above result in another deduction, I would not make an erroneous follow-on error of assuming it equalled zero.
Does it tell you from which side it's approaching 0? Don't think so.

lim x->∞ (2/x) > lim x->∞ (1/x) for x > 0
lim x->∞ (2/x) - lim x->∞ (1/x) > 0 for x > 0


lim x->∞ (2/x - 1/x) > 0 for x > 0
lim x->∞ (1/x) > 0 for x > 0

1/x > 0 for x > 0

That's a tautology.

Also if we do the same for -1/x it approaches 0 from the other side. So... you've gained nothing.

I think you are fighting to preserve your use of infinity-limits :)
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attofishpi
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Re: Universe can't be infinite.

Post by attofishpi »

In the real world - as we continue to approach zero we are left with either an event or not an event - the binary finality to the 'infinitely' small.
TimeSeeker
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Re: Universe can't be infinite.

Post by TimeSeeker »

In the world of mathematics you get to be a hypocrite or a pragmatist. Make your choice :)

Chasing the LNC is harmful idealism.
devans99
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Re: Universe can't be infinite.

Post by devans99 »

I see no inconsistency in my use of approximately equals. Calculus would be better off if it adopted this approach IMO.

Now that we've eliminated Actual Infinity, that implies negative Actual Infinity does not exist which has exactly the same structure as past eternity:

{ ..., 2015, 2016, 2017, 2018 }
{ ..., -4, -3, -2, -1 }

Neither have a start so they are both only partially defined. IE they are undefined. Eternity can't exist so time must have a start.
TimeSeeker
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Re: Universe can't be infinite.

Post by TimeSeeker »

devans99 wrote: Tue Nov 27, 2018 2:31 pm I see no inconsistency in my use of approximately equals. Calculus would be better off if it adopted this approach IMO.
I see ambiguity in your use of "~=".

A = B
A < B
A > B

A ~= B is covered in the above FOR ALL REAL NUMBERS.

If you believe otherwise, show me a falsifier.
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attofishpi
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Re: Universe can't be infinite.

Post by attofishpi »

TimeSeeker wrote: Tue Nov 27, 2018 2:29 pm In the world of mathematics you get to be a hypocrite or a pragmatist. Make your choice :)

Chasing the LNC is harmful idealism.
Since we are talking about whether the universe can be infinite, I am going with pragmatist - in that 'matter' has a finite point - either an event or not an event, at it most finite (small) point.
TimeSeeker
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Re: Universe can't be infinite.

Post by TimeSeeker »

attofishpi wrote: Tue Nov 27, 2018 2:35 pm Since we are talking about whether the universe can be infinite, I am going with pragmatist - in that 'matter' has a finite point - either an event or not an event, at it most finite (small) point.
Agreed, but the moment you USE an infinity in your equation you have violated the laws of logic and are resorting to heuristics.
Like I said earlier - admirable and pragmatic! But if you want to be a purist and pretend to adhere to the LNC, such hypocrisy will bite you in the ass :)

This universe has no room for idealists.
devans99
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Re: Universe can't be infinite.

Post by devans99 »

TimeSeeker wrote: Tue Nov 27, 2018 2:32 pm
devans99 wrote: Tue Nov 27, 2018 2:31 pm I see no inconsistency in my use of approximately equals. Calculus would be better off if it adopted this approach IMO.
I see ambiguity in your use of "~=".

A = B
A < B
A > B

A ~= B is covered in the above FOR ALL REAL NUMBERS.

If you believe otherwise, show me a falsifier.
Well for the '~' to be complete, we need to decide what level of precision constitutes approximately. I've suggested that we just use it for limits, IE arbitrarily high precision.
TimeSeeker
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Re: Universe can't be infinite.

Post by TimeSeeker »

devans99 wrote: Tue Nov 27, 2018 2:40 pm Well for the '~' to be complete, we need to decide what level of precision constitutes approximately. I've suggested that we just use it for limits, IE arbitrarily high precision.
How? :)

https://en.wikipedia.org/wiki/Decision_problem

All decision problems which are not algorithmic (deductive) require a value judgment.

Like I said earlier. ANY use of the ~= symbol incurs the precision-range trade-off.
https://en.wikipedia.org/wiki/Floating-point_arithmetic
devans99
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Re: Universe can't be infinite.

Post by devans99 »

TimeSeeker wrote: Tue Nov 27, 2018 2:40 pm
devans99 wrote: Tue Nov 27, 2018 2:40 pm Well for the '~' to be complete, we need to decide what level of precision constitutes approximately. I've suggested that we just use it for limits, IE arbitrarily high precision.
How? :)

https://en.wikipedia.org/wiki/Decision_problem

All decision problems which are not algorithmic (deductive) require a value judgment.

Like I said earlier. ANY use of the ~= symbol incurs the precision-range trade-off.
https://en.wikipedia.org/wiki/Floating-point_arithmetic
This is off topic and you are not making sense. How? We simply adopt it as a mathematical notational convention.
TimeSeeker
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Re: Universe can't be infinite.

Post by TimeSeeker »

devans99 wrote: Tue Nov 27, 2018 2:51 pm This is off topic and you are not making sense. How? We simply adopt it as a mathematical notational convention.
It is not off-topic.

How many digits do you propose is "approximate enough" for 1 ~= 1?

5? 10? 100? 1000? 1000000? 100000000000000000? 1000000000000000000000000000000000000000000000000000000000000000000000?

How would we decide on this magical number?
devans99
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Re: Universe can't be infinite.

Post by devans99 »

TimeSeeker wrote: Tue Nov 27, 2018 2:53 pm
devans99 wrote: Tue Nov 27, 2018 2:51 pm This is off topic and you are not making sense. How? We simply adopt it as a mathematical notational convention.
It is not off-topic.

How many digits do you propose is "approximate enough" for 1 ~= 1?

5? 10? 100? 1000? 1000000? 100000000000000000?

How would you decide?
It's a potentially infinite number of digits. It's only for use with limits which become arbitrarily close to a given value.
TimeSeeker
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Re: Universe can't be infinite.

Post by TimeSeeker »

devans99 wrote: Tue Nov 27, 2018 2:54 pm It's a potentially infinite number of digits. It's only for use with limits which become arbitrarily close to a given value.
Weasel words!

How many digits makes 1 ~= 1?
devans99
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Re: Universe can't be infinite.

Post by devans99 »

Like I said its potentially infinite number of digits. IE it has to be approximately equal to arbitrarily high precision. So that is no fixed number of decimal places.
TimeSeeker
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Re: Universe can't be infinite.

Post by TimeSeeker »

devans99 wrote: Tue Nov 27, 2018 2:58 pm Like I said its potentially infinite number of digits. IE it has to be approximately equal to arbitrarily high precision. So that is no fixed number of decimal places.
Infinite number of digits? How does that work if infinities are only potential not real?

You are just trying to sneak infinity through the back door again!
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