## 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.

devans99 wrote: Tue Nov 27, 2018 1:32 pmYes.
OK cool. So.

lim x->∞ (1/x) ~= 0
lim x->∞ (2/x) ~= 0
lim x->∞ (2/x) lim ~= lim x->∞ (1/x)

since we never actually evaluate FOR infinity (that's illegal) then:

at x = 0.01 -> 200 ~= 100
at x = 1 -> 2 ~= 1
at x = 99999999999999 then 0,0000000002 =~ 0,0000000001

Is this correct?
Last edited by TimeSeeker on Tue Nov 27, 2018 1:39 pm, edited 1 time in total.
attofishpi
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### Re: Universe can't be infinite.

Maths is the only form that infinities exist, and as a form of convenience.
TimeSeeker
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### Re: Universe can't be infinite.

attofishpi wrote: Tue Nov 27, 2018 1:39 pm Maths is the only form that infinities exist, and as a form of convenience.
Yes. But You have to listen to his post-hoc justification

He rejects infinities BUT..... he wants to use them for limits

And he objects to being called a hypocrite for engaging in a performative contradiction.
attofishpi
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### Re: Universe can't be infinite.

TimeSeeker wrote: Tue Nov 27, 2018 1:40 pm
attofishpi wrote: Tue Nov 27, 2018 1:39 pm Maths is the only form that infinities exist, and as a form of convenience.
Yes. But You have to listen to his post-hoc justification

He rejects infinities BUT..... he wants to use them for limits
Sure, but I am confused after the 3rd smiley.
devans99
Posts: 158
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### Re: Universe can't be infinite.

TimeSeeker wrote: Tue Nov 27, 2018 1:39 pm
devans99 wrote: Tue Nov 27, 2018 1:32 pmYes.
OK cool. So.

lim x->∞ (1/x) ~= 0
lim x->∞ (2/x) ~= 0
lim x->∞ (2/x) lim ~= lim x->∞ (1/x)

since we never actually evaluate FOR infinity (that's illegal) then:

at x = 0.01 -> 200 ~= 100
at x = 1 -> 2 ~= 1
at x = 99999999999999 then 0,0000000002 =~ 0,0000000001

Is this correct?
Just because two functions are equal as x tends to infinity does not mean they are equal for other values of x, as your calculation shows.
TimeSeeker
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Joined: Tue Sep 11, 2018 8:42 am

### Re: Universe can't be infinite.

devans99 wrote: Tue Nov 27, 2018 1:42 pm Just because two functions are equal as x tends to infinity does not mean they are equal for other values of x, as your calculation shows.
But they are NOT equal as x tends to infinity!!!!!!

If they were equal you would have said:

lim x->∞ (1/x) = 0
lim x->∞ (2/x) = 0

lim x->∞ (1/x) ~= 0
lim x->∞ (2/x) ~= 0

Does = mean the same thing as ~= now ?!?!?!?
devans99
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### Re: Universe can't be infinite.

The two functions are approximately equal when x tends to infinity. They are not not equal for any other value of x.
TimeSeeker
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### Re: Universe can't be infinite.

devans99 wrote: Tue Nov 27, 2018 1:46 pm The two functions are approximately equal when x tends to infinity. They are not not equal for any other value of x.
What does "approximately equal" mean?!? Things are either equal, smaller or larger than each other!

When dealing with real numbers only one of these is true!

A = B
A < B
A > B

What the hell does A ~=B mean ?!?!?!?
devans99
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### Re: Universe can't be infinite.

TimeSeeker wrote: Tue Nov 27, 2018 1:50 pm
devans99 wrote: Tue Nov 27, 2018 1:46 pm The two functions are approximately equal when x tends to infinity. They are not not equal for any other value of x.
What does "approximately equal" mean?!? Things are either equal, smaller or larger than each other!

ONLY ONE OF THESE IS TRUE:

lim x->∞ (2/x) = lim x->∞ (1/x)
lim x->∞ (2/x) < lim x->∞ (1/x)
lim x->∞ (2/x) > lim x->∞ (1/x)

What the hell does this mean !?!?
lim x->∞ (2/x) ~= lim x->∞ (1/x)

What the hell does ~= mean ?!
lim x->∞ (2/x) ~= lim x->∞ (1/x)
Both expressions tend to zero as x tends to infinity. But at no point on the way to infinity are the two expressions equal. So we write approximately equal.

We can also write
2/x > 1/x for all x except 0.

So maybe its best to write:

lim x->∞ (2/x) >~ lim x->∞ (1/x)

So '>~' denotes its approximately equal with 1/x always being less than 2/x.
TimeSeeker
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Joined: Tue Sep 11, 2018 8:42 am

### Re: Universe can't be infinite.

devans99 wrote: Tue Nov 27, 2018 1:56 pm lim x->∞ (2/x) ~= lim x->∞ (1/x)
Both expressions tend to zero as x tends to infinity. But at no point on the way to infinity are the two expressions equal. So we write approximately equal.

We can also write
2/x > 1/x for all x except 0.

So maybe its best to write:

lim x->∞ (2/x) >~ lim x->∞ (1/x)

So '>~' denotes its approximately equal with 1/x always being less than 2/x.
Sorry. No can do. This is special pleading.

lim x->∞ (2/x) lies on the real number line, does it not?
lim x->∞ (1/x) lies on the real number line, does it not?

A = B
A < B
A > B

Can ALWAYS be determined for any two real numbers, and since we never actually evaluate AT infinity itself then I will settle for nothing less than:
lim x->∞ (2/x) > lim x->∞ (1/x) for x > 0
lim x->∞ (2/x) < lim x->∞ (1/x) for x < 0
Last edited by TimeSeeker on Tue Nov 27, 2018 2:04 pm, edited 3 times in total.
devans99
Posts: 158
Joined: Wed Nov 21, 2018 1:21 pm

### Re: Universe can't be infinite.

TimeSeeker wrote: Tue Nov 27, 2018 1:59 pm
devans99 wrote: Tue Nov 27, 2018 1:56 pm lim x->∞ (2/x) ~= lim x->∞ (1/x)
Both expressions tend to zero as x tends to infinity. But at no point on the way to infinity are the two expressions equal. So we write approximately equal.

We can also write
2/x > 1/x for all x except 0.

So maybe its best to write:

lim x->∞ (2/x) >~ lim x->∞ (1/x)

So '>~' denotes its approximately equal with 1/x always being less than 2/x.
Sorry. No can do. This is special pleading.

lim x->∞ (2/x) lies on the real number line, does it not?
lim x->∞ (1/x) lies on the real number line, does it not?

A = B
A < B
A > B

Can ALWAYS be determined for any two real numbers, and since we never actually evaluate AT infinity itself then I will settle for nothing less than lim x->∞ (2/x) > lim x->∞ (1/x)
But its possible for BOTH of the following to be true at the same time:

A > B
A ~ B

So you see the advantage to the '>~' notation?
TimeSeeker
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### Re: Universe can't be infinite.

devans99 wrote: Tue Nov 27, 2018 2:02 pm A ~ B
Can you give me a value of X for which A ~ B is true ?
devans99
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### Re: Universe can't be infinite.

TimeSeeker wrote: Tue Nov 27, 2018 2:03 pm
devans99 wrote: Tue Nov 27, 2018 2:02 pm A ~ B
Can you give me a value of X for which A ~ B is true ?
A ~ B
1 ~ 1

For example.
TimeSeeker
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### Re: Universe can't be infinite.

devans99 wrote: Tue Nov 27, 2018 2:10 pm 1 ~ 1
Can you explain what this adds over and above =, < and > when dealing with real numbers?
devans99
Posts: 158
Joined: Wed Nov 21, 2018 1:21 pm

### Re: Universe can't be infinite.

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.