#help-28

1 messages · Page 281 of 1

twin wolf
#

in order to move forward in life you must look backwards

knotty grail
#

an x direction is to help you locate

olive saffron
#

the "x axis" is simply an infinitely long 'line' that you can define

covert heath
#

btw @olive saffron for the record, OE replied to this and explained stuff really well until he had to go for a lecture

olive saffron
#

in 3D space you can choose any straight line and call this the x-axis

covert heath
#

so i dont know what this is about

#

i thought we had moved on

austere cove
#

lecture was cancelled, no one showed up but me.

valid nimbus
knotty grail
#

holy moly

covert heath
#

Hi OE!

austere cove
#

hi!

covert heath
#

welcome back

austere cove
#

I'm back

olive saffron
covert heath
#

he just copypasted the same thing again.

#

holy shit

wary condor
olive saffron
#

I see

valid nimbus
#

wouldn't it end up in the wrong place

#

most likely

olive saffron
#

Well there is little to be gained with a running meta-narrative on what has happened in this channel

valid nimbus
#

when the object b is already placed

austere cove
#

so first off, "x" direction is leading, you don't even need the directions to be orthonormal, just independent. Your space might not have a well defined notation of the "x" direction as we generally think of it.

olive saffron
#

You can create a 3D space without any objects in it whatsoever

austere cove
#

however, for any euclidean space we can choose an orthonormal set of vectors that span it.

wary condor
valid nimbus
olive saffron
#

Sure, you can consider a line to be an object in some sense

austere cove
#

Well, I did explain how to construct a line previously.

olive saffron
#

Likewise for a point

valid nimbus
#

if u take x, y, z axis to be in any direction

#

u have have multiples of co ordinates and equations

#

that lead to the same line

olive saffron
#

Define "construct"

covert heath
valid nimbus
covert heath
#

it's like a broken record

#

I thought we had moved on!!

#

damnit

valid nimbus
#

hmm well

austere cove
olive saffron
#

Again, the meta-narrative doesn't help

austere cove
#

ok, so there are two separate things going on here. First, you have a space, and second, you have some set of coordinate systems.

covert heath
#

Because... it was answered, right?

austere cove
covert heath
#

Anyway if you're fine reexplaining I'm not complaining

austere cove
#

Any coordinate system you define can address any point uniquely in the space with a ordered triple

olive saffron
#

One must assume good faith until given good reason to assume otherwise

austere cove
#

And the same point can have different addresses when different coordinate systems are in use.

covert heath
#

but maybe one can just go back and reread and ask follow up questions?

#

rather than the same thing again

covert heath
austere cove
#

So circling back (no pun intended), we have a space, and we have points in that space, and we have multiple ways of specifying how to get to points in that space (coordinate systems)

valid nimbus
#

currently, my confusion just lies in this;
there's set 2 points, from point a u have to reach point b via a line, but if someone says just any co ordinates such as 5,0,0 for point b and point a to be 0,0,0.
then u can take numerous directions as x, y and z axis, u would have numerous answers, but only one of them is correct.

My question is, what tells the point a which one is the correct representation in relative directions of point a

austere cove
#

any coordinate system is equal to any other, in the sense that if we construct things like lines, etc using the coordinate systems, the lines will always be the same.

#

even if the numbers we use to represent the points are different between coordinate systems, the points themselves are the same points.

valid nimbus
#

well yes

austere cove
#

congrats by the way, we've argued about this enough that you've gotten active catgiggle

valid nimbus
#

5,0,0 with x axis being in one direction and so and so, could be the same as 0,10,6384 with another representation of x axis

austere cove
#

exactly.

valid nimbus
#

But

olive saffron
#

There is a mathematical concept of "changing basis" which you seem to be kinda hitting on without necessarily realising it

valid nimbus
# austere cove exactly.

if we have a situation where we have no other information as to which direction we should represent x, y and z axis towards to get to the right point B

onyx glen
valid nimbus
austere cove
valid nimbus
#

hmmmmmmmmmmmmmmmmm

valid nimbus
#

but then their connection broke off

austere cove
#

For instance, you are correct that there are multiple (infinite really!) coordinate systems such that point A is at (5, 0, 0)

valid nimbus
#

before human 2 could specify the x, y and z by a map

#

now how would human 1 navigate?

austere cove
#

without more information, we can't figure out which coordinate system is in use just from this

valid nimbus
#

I see

#

so human 1 cannot navigate

austere cove
#

without more information

#

you need to give the coordinate system. Alternatively, you can give the locations of 4 points

#

(noncoplanar)

valid nimbus
#

what really bothers me is, how can 3 dimensional objects even realize something so small

#

i mean

austere cove
#

I don't understand what you mean by "realize" here

valid nimbus
#

Also

austere cove
#

we are dealing with math, if I say a point is at (pi, e, -1) then it is precisely there.

#

error is its own can of worms

valid nimbus
austere cove
#

nothing, 1d objects can be infinite

#

a line is infinite.

covert heath
#

3d space is infinite.

valid nimbus
#

I mean it in actual size

#

3d objects

#

Because

#

we can be infinities but bigger and smaller right?

#

just like the set of natural no.s

austere cove
#

even "finite" objects tend to be comprised of infinite sets of points. A sphere is every point that is within a certain distance of another.

valid nimbus
#

and rational numbers

valid nimbus
#

but

austere cove
#

natural numbers and rational numbers are both the same size infinity, for the record. But let's not confuse things by introducing new topics.

valid nimbus
#

i dont see the limitation of 3d masses

#

being finite

#

I don't see the limitation that I see for numbers like 3

austere cove
#

I don't understand what you mean by "masses" here.

valid nimbus
#

3d objects being, 3 meters square or 5 meters cube

proud dirge
#

Why would there be a limitation

valid nimbus
austere cove
valid nimbus
#

a meter cube that we measured couple also be infinite

austere cove
#

it has a finite volume, but the points themselves are infinite.

valid nimbus
#

but this object is like rational numbers, and more infinite than a meter cube of object

valid nimbus
#

a sphere could be infinite

austere cove
#

every sphere has infinite points inside of them.

valid nimbus
#

right but

#

how about u see a thought experiment first

austere cove
#

so what do you mean by infinite here? What I'm trying to get you to do is make what you're talking about precise.

restive geyser
#

That is, these words have meanings already; so if you're going to use a differing meaning, it's your job to explain what they are.

valid nimbus
# valid nimbus how about u see a thought experiment first

imagine that, just like our universe, another exact copy of the universe is present in our 3d space,
But this copy universe, is soo small in diameter.
as in; if we take a scale of one quark to this entire universe, the copy universe would be like that quark, to an actual our quark

austere cove
#

because it is my thought that maybe the reason you're getting so confused over things is that you are being imprecise, and then tripping over yourself when you attempt to use imprecise things to reason.

valid nimbus
#

exact same perceptions

#

but different sizes

#

wouldn't this be able to be possible

#

and we be infinite, really

#

just like set of natural numbers

#

and rational numbers

#

we differ in sizes

#

but are infinite

#

how about this?

restive geyser
#

stop talking

#

like this

#

for each phrase

valid nimbus
#

because I don't see something quantifing 3d objects

#

alright

proud dirge
austere cove
#

If you shrink the entire universe down to a point, and then ask "what happens if I explore within this point"? No. If you shrink it to a point, then it ceases to be 3d. Points are definitionally 0d.

restive geyser
#

It's really difficult to read and parse through

austere cove
#

anything larger than a point, and it wouldn't matter.

valid nimbus
austere cove
#

we just have a different set of coordinates to deal with the small scales involved.

valid nimbus
#

and in that copy universe, there would be another copy universe

#

same exact idea

#

and so and so

#

making us infinite

#

so mass could be infinite right

austere cove
#

you're confusing several concepts here

valid nimbus
valid nimbus
austere cove
#

we're not talking about the "universe" or "mass" or anything do to with physics. We are still talking purely mathematics, yes?

valid nimbus
#

but I just wanna know why mass isn't infinite like this

jade pebble
#

what is the original question?

valid nimbus
#

but consider this a thought experiment of maths

#

why would mass be limited here

#

I mean.. 3d objects

jade pebble
#

well, what was.

valid nimbus
#

whyd they be finite here

austere cove
#

mathematically speaking what is "mass"? Mass is typically a physical quantity of objects in physics. Not in mathematics.

valid nimbus
#

right sorry

#

3d objects, whyd they be finite here

maiden vapor
jade pebble
austere cove
#

What do you mean by finite and infinite?

proud dirge
valid nimbus
#

if u couldn't do that infinitely without breaking down into 0 of each

austere cove
valid nimbus
#

then that would be finite

valid nimbus
austere cove
#

any 3d object that consists of infinitely many points, such as lines, circles, discs, squares, balls, etc, would be infinite in this framework

valid nimbus
#

it isn't just points tho

#

it's infinitely many actual 3d objects

#

not just 0d points

#

actual 3d objects

#

so that would make it infinite right

austere cove
#

define what an "actual 3d object" is, please.

valid nimbus
#

length width breadth

covert heath
#

length width breadth is an object?

austere cove
#

a pyramid doesn't have a single length width and breadth?

valid nimbus
austere cove
#

would you consider a tetrahedron to be a 3d object?

valid nimbus
#

but it's non zero and positive

jade pebble
#

A point in an n dimensional space can be described as a list of n values.

covert heath
#

also why are we talking about infinities now

#

i mean sure we can talk about infinities

#

but did you figure how lines work, yet

valid nimbus
#

Tetrahedrpn

covert heath
#

are we gish galloping

austere cove
#

I think what you're saying is roughly, and correct me if I am wrong: "a 3d object is a set of points for which the smallest rectangular prism that contains all of the points is not degenerate (i.e. has a non-zero volume)"

austere cove
#

is this what you are trying to define?

valid nimbus
#

points have no width, no length no breadth

#

even if u place 2 points together

#

it would form no length no width

#

no breadth

covert heath
#

valid question

valid nimbus
#

and

#

that's why I argue 3d objects essentially have to be infinite

#

because there's nothing that makes them up finitely

#

u have infinitely smaller 3d "objects" that make them up

#

like numbers of a set

covert heath
#

'numbers of a set'?

valid nimbus
#

well, bad analogy maybe

covert heath
#

analogy?

proud dirge
jade pebble
#

moderators, please don't purge this channel, let this be historic site.

covert heath
#

why bring up analogies

split hatch
#

Why must a "3d object" be infinite? Take any 5 vertices that form a square pyramid, then this set of 5 points is surely 3-dimensional?

valid nimbus
covert heath
valid nimbus
#

a point has 0 width

proud dirge
#

So what

austere cove
#

@valid nimbus take a cube, and consider any vertex. This vertex is joined to 3 others. Now remove the entire cube except for the three lines that join these 4 vertices. Is this object a "3d object"?

valid nimbus
#

it would be 0 width

proud dirge
#

No

valid nimbus
#

wouldn't be able to touch positive

jade pebble
#

A point in an n dimensional space can be described as a list of n values.

valid nimbus
#

hoe so

#

0 times n is 0

proud dirge
#

You have infinite points

jade pebble
#

A point in an n dimensional space can be described as a list of n values. @valid nimbus

proud dirge
#

You can't just add 0 infinite times

#

A course in measure theory would help here

austere cove
#

or topology yeah

covert heath
valid nimbus
#

I think ur onto something here

#

well

#

the 3 lines

#

would be 2d

covert heath
#

this would end so much quicker if he heeded any of our advice to 'just pick up a book'

valid nimbus
#

but the intersection

#

should have

#

width length breadth

#

sheesh

austere cove
valid nimbus
#

yeah same same

#

hmmmm

#

but

valid nimbus
#

something doesn't feel right

jade pebble
#

A POINT IN AN N DIMENSIONAL SPACE IS A LIST OF N VALUES, AN OBJECT IN AN N DIMENSIONAL SPACE IS A COLLECTION OF SUCH POINTS, OR LISTS.

valid nimbus
#

how can u have

#

infinite points

#

at one point

covert heath
#

wha

proud dirge
#

what

austere cove
#

sorry, but that question is nonsensical

valid nimbus
#

well u see here

#

those 3 lines

#

are one dimensional

#

but the intersection, if it is 3 dimensional, that means it's made up of infinite points

#

but it should be just one point

#

of really small lwb

austere cove
#

so I would define an "object" in 3d space as I defined it before. it's a set of points for which the smallest rectangular prism that contains all the points has a non-zero volume. For some precise definition of smallest (infinum)

valid nimbus
#

hmm

austere cove
#

by that definition, not all 3d objects have infinite numbers of points.

#

but most common 3d objects that you care about do

proud dirge
#

This whole conversation is the reason why definitions are important in mathematics

austere cove
#

note that you shouldn't conflate the notion of infinite amounts of points with infinite volume

valid nimbus
#

sorry I don't understand something here

jade pebble
austere cove
valid nimbus
jade pebble
valid nimbus
#

I'd understand why not for something like a 1/2/3d object

#

but not a 0d object

#

that shares no space

jade pebble
#

i am trying my best ok

proud dirge
#

And a point is a point

austere cove
#

How would you distinguish two points from each other, if they are located in the same spot?

#

two objects in math are the same if every feature that we care about is the same, right?

#

the only features a point has is its location

valid nimbus
covert heath
#

what?

austere cove
#

I can define a point by simply taking my coordinate system, and then identifying it using the coordinate system

#

My point is at (0, 0, 5) for instance

#

now you say that I have "infinitely many" points at (0, 0, 5), but how can you tell?

#

there certainly is a point at (0, 0, 5)

#

If there are infinitely many points at some coordinates but not others how would you distinguish between the two cases?

#

(heck if there are 2 points at a point instead of just 1 how would you tell?)

#

@valid nimbus you still with us?

jade pebble
#

archive this channel as a historical site and create a new help 28 channel.

full forumBOT
#

@valid nimbus Has your question been resolved?

jade pebble
#

he's back

covert heath
#

he has!

valid nimbus
#

well you'd be right kind of

valid nimbus
austere cove
#

there is no next point

valid nimbus
#

5.00000...1?, 0,0

valid nimbus
#

why can't u

#

make

#

another one

#

Beside it

austere cove
#

this is a feature not of our coordinate system, but of any numbering system that is "dense"

#

The rationals, for instance, are dense.

#

Let's say I define a number, let's call it x

#

and then I say that the next number is y

#

but then I can construct a new number between them

valid nimbus
#

Hm

austere cove
#

we have y > x, so y-x is positive

#

then I consider the number x + (y-x)/2

#

this number is strictly between x and y

#

so there is no "next" number

proud dirge
#

I don't think bringing more concepts into the conversation is a good idea 😭

restive geyser
#

-# Unfortunately, there's looking to be little alternative

valid nimbus
proud dirge
#

No

covert heath
#

no

austere cove
valid nimbus
#

hmmm

#

well

#

okay, how do u categorize masses then? if they're made up of infinitely small points, how many infinitely small points is 1 unit?

austere cove
#

So you're asking a lot of questions that require more learning on your part to understand the answers.

#

Specifically, as mentioned I think half a dozen times so far, you're looking for "measure theory"

valid nimbus
#

Hmm

austere cove
#

I know

#

it's a bit of a trek to get from where you're at to where you need to go

proud dirge
#

Learning measure theory in 9th grade would be wild

azure onyx
#

if the helper is asking questions that demand knowledge of particular fields, I think it's better to be honest than to tell them, "you'll get it later".

austere cove
#

but I'll try to boil it down

azure onyx
#

helpee*, sorry.

austere cove
#

so let's ignore 3d for a moment

jade pebble
austere cove
#

let's instead take an easier case of 1d.

valid nimbus
#

hmm

austere cove
#

now we can define a measure of 1 as all of the real numbers on the interval of (0, 1)

#

so if we have a line segment from (-2, 3) then that line segment has a measure of 5

#

we start asking questions about what happens if we start removing points, how does this change the measure?

valid nimbus
#

Hm

austere cove
#

we can actually remove infinite sets points without changing the measure

#

but formalizing this is the key

#

we can also have finite sets of points with 0 measure.

#

but again, which sets matter, and formalizing it is the key

#

what I'm trying to get at is you're asking good questions, but the answers to your questions are complicated and depend on mathematics that you probably won't encounter for a good 5+ years.

valid nimbus
#

hmm

austere cove
#

we generally deal with "nice" sets

#

so if your set of points is "nice" for some precise definition of nice

#

then we can say that the measure (which in 3d space we typically refer to as a volume) is a particular limiting process that involves counting up tiny cube volumes and defining the volume of each cube to the its side length cubed.

valid nimbus
#

i see

austere cove
#

but there are stranger spaces we can work in than simple 3d euclidean space, and different notions of volume we can use, and the key is all of this needs to be defined.

#

nothing is "for free" in math, we have to be very careful how we import our intuitions

valid nimbus
#

wait for some reason this brings me back to that idea

#

if you wanna form a line between two points, you have to specify the x axis, y axis and z axis direction, which is usually given by the co ordinate system

#

But if direction is a line

#

Like axis would be depicted as,

#

Then you need to define that x axis, y axis and z axis's directions

#

in the form of a line

#

but to generate that line

#

you need to specify the axis you're using

#

while doing so, you form lines of direction

#

and it continues

austere cove
#

so imagine I have a bag of points.

#

they are unlabeled.

valid nimbus
#

yeah

austere cove
#

but I have a method of grabbing points out of the bag.

#

just at random

valid nimbus
#

Ok

austere cove
#

I grab a point, I don't know where it is in this space, but I say "Ok, this point, I will name O, and I will say this point is (0, 0, 0)"

valid nimbus
#

Ok

#

I can agree upon that

austere cove
#

I grab a second point, I don't know where it is in this space, but I will say, "This point is A, and I will say this point is at (1, 0, 0)"

valid nimbus
#

Okay

#

that's cool too

austere cove
#

I grab a third point, I don't know where it is, but I will say "This point is B, and I will say this point is at (0, 1, 0)" but only after I test to make sure this point isn't in on the line OA

#

if it is on that line, I just grab a different point at random until it's not on that line

#

I can make the line OA because I already have O and A

valid nimbus
#

Hmm

#

you can

#

but

#

u need an equation

#

to do so

#

us drawing it isn't perfect like us saying oa

#

an equation, that shows all points of a set is what we need

#

right?

austere cove
#

What I'm saying is I can identify if two points are the same point by seeing if they're the same point in the space.

#

so if I have B and I have the line OA then these are both sets, and I can take the set intersection

#

if this intersection is empty then B is a valid third point, if it's not then I choose a different point

valid nimbus
# valid nimbus right?

but with this equation, we need to know about which direction x, y and z axis that the equation operates from, but the problem is, this equation literally would be for showing which direction x, y and z axis for our current line is

valid nimbus
#

u can get a point where it's not in oa line

valid nimbus
#

it seems self contradictary

#

or paradoxical

covert heath
#

why foes it seeem self contradictory

#

or paradoxical

valid nimbus
#

right now

#

you need to define the directions of x, y and z axis

covert heath
#

no you dont

austere cove
#

you're thinking about lines in terms of equations

valid nimbus
austere cove
#

but you don't need to think about lines in this way, you can think about this in terms of sets of points that satisfy some property

valid nimbus
#

sets of points

restive geyser
#

But that's not the only way you can define a line

valid nimbus
austere cove
valid nimbus
#

hmm

#

what else can u do

#

other than an equation

#

that shows an actual line

austere cove
#

I could just say, "here is an infinite bag of points" and it just so happens that each point in this infinite bag has that property

valid nimbus
austere cove
#

I just did

covert heath
#

he has

austere cove
#

Formally, this would be something like ${ P \mid P \in \overline{OA} }$

glossy valveBOT
#

OmnipotentEntity

austere cove
#

this is perfectly valid

valid nimbus
# austere cove I just did

I can say too that, in my mirror universe, there is a bag that has infinite points and follows the same property that omnipo entity described for his bag, but it follows a property that doesn't count as an actual property yet is a property with all mathematical rigour that exists and disturbs his logic but it would count as the same bag for some odd reason, that follows all axioms properly but disturbs it and contradicts it while being rigorously accepted by actual mathematics

covert heath
valid nimbus
# austere cove this is perfectly valid

well, that's only perfectly valid until u imagine logics/properties that disturb your thesis while not having to be considered as a different property bag, but still disturbing it

#

I'm not sure how or when or where

#

but in English, I can just say like that

valid nimbus
#

disturbing your logic, but still having to get counted as the same bag with properties

austere cove
valid nimbus
#

how would u say this then?

austere cove
#

(we are assuming euclidean space, so there is a unique line)

valid nimbus
#

u need to speak in terms of an equation

covert heath
#

(im fine thinking of other definitions)

austere cove
#

Let's talk about the Greeks. The Greeks did geometry of the plane without coordinates

#

we can construct a line via two points and a straight edge.

valid nimbus
#

the greeks drew pencil lines that mathematically wouldn't be counted as perfect lines

austere cove
#

no equation necessary

valid nimbus
restive geyser
austere cove
valid nimbus
#

but isn't mathematically rigorous enough

#

to differentiate if my nose

#

is different than those

#

why can't my nose, 3000 years later

restive geyser
#

Write a full sentence, THEN press enter, ffs

valid nimbus
#

be counted as a part of that line?

#

alright

covert heath
#

(ftr i still wanna know wht logics are)

valid nimbus
austere cove
#

So in order to define a line, we need to define a few things about our space and about distance

austere cove
#

which means we need to define our metric

covert heath
austere cove
#

and now we're getting kind of into the weeds a bit.

covert heath
#

dont do thst.

valid nimbus
valid nimbus
austere cove
#

So our space is equipped with a notion of distance

jade pebble
#

if this entire conversation was spent explaining measure theory, @valid nimbus would have a phd by now.

austere cove
#

for any two points in our space we can define a function d(x, y) to give us back a number that represents the distance between these two points.

knotty grail
valid nimbus
#

I thought distance was relative to human units like a metre, a football field, a kilometre, 17 hamburgers, etc..

#

how do u define absolute distancw

covert heath
#

units

valid nimbus
#

without taking into consideration of relative units

valid nimbus
austere cove
#

to what?

covert heath
#

no its not

jade pebble
valid nimbus
austere cove
#

sure

valid nimbus
#

then it's relative to oa

covert heath
#

no its not

valid nimbus
#

and if u take oa as 17 units of ch

#

it's relative to ch

valid nimbus
#

if u say 10 units why can't I say 10039 units then?

#

that's why it's relative

austere cove
#

may I ask a favor of you

valid nimbus
#

yeah

austere cove
#

can I get you to read a thing?

valid nimbus
#

yeah

#

what is it?

covert heath
austere cove
valid nimbus
covert heath
#

a unit is whatever i say it is

valid nimbus
#

I can say a unit is whatever I say it is

covert heath
valid nimbus
#

and how do we mathematically, convey the true distance between a and be is

#

maybe

valid nimbus
#

Actually

covert heath
#

its the distance in units

austere cove
valid nimbus
#

Hmm

covert heath
#

(0,0,0) to (1,0,0) is 1 unit

#

literally

austere cove
#

I can't find it

#

but essentially, you're mistaking the map for the place

#

our space is the place, our units and metrics and so on are just a map

valid nimbus
austere cove
#

the maps should agree with the place, but they are not themselves the place.

valid nimbus
#

I mean, distance between a and b

covert heath
#

distance (a measure) is in units

valid nimbus
#

why do u need to say they're in so and so units?

#

what next

covert heath
#

actually not sure im using measure correctly

valid nimbus
covert heath
#

OE can correct me

#

(because words have meanings which matter)

valid nimbus
#

Hmm

#

so u could define a line

#

by talking about those units

#

hmmm

covert heath
#

no.

valid nimbus
#

no? why else the necessity of those units then

#

u just measure the distance for what?

covert heath
#

for MEASURES

#

again not sure im using the word correctly.

#

but.

#

lengths areas volumes allat

austere cove
#

I mean, yes, honestly, we can define and translate between different measures, and we commonly call these units of different sorts to distinguish them

#

the idea is there is some correspondence to any consistent set of measures and units that you can choose that all agree with each other.

valid nimbus
austere cove
#

many maps, all describing the same thing.

#

but they're all just maps

valid nimbus
#

when is measuring a distance between 2 points useful?

restive geyser
valid nimbus
#

are u playing "who's bigger"

covert heath
valid nimbus
#

or are u playing "I'm stronger"

austere cove
#

Stop taking pot shots please

valid nimbus
#

Alright

austere cove
#

if you're interested in learning, we're here to help

covert heath
#

i cant imagine why MEASURING STUFF is important

valid nimbus
#

I won't criticise doing it

#

but like why.. what next

austere cove
#

we can measure distances

#

how we choose to measure them isn't important, the exact units aren't important

covert heath
#

do you want rigorous... anything to do with spaces?

#

rigorous probability?

austere cove
#

and the reason why it's not important is because any other metric that describe the same space will have to give results that agree

valid nimbus
#

and this distances seems like human needs to me

covert heath
#

nobody said its relative.

austere cove
#

When I say distance, it has a lot of baggage in your brain that you've imported from the outside world.

covert heath
#

arbitrary \neq relative

valid nimbus
austere cove
#

but I'm not referring to any of that.

#

distance as it exists in the world of mathematics is just a function

#

it takes two input points, returns a positive value, and it has to satisfy the triangle inequality property, symmetry, and the fact that the distance from a point to itself is 0

#

any function that satisfies these properties is a metric.

restive geyser
#

(I'd rather something easier to digest than Wikipedia for this, tbh)

valid nimbus
# austere cove distance as it exists in the world of mathematics is just a function

but something seems troubling to me that distance is an actual real function, because distance in our real world is just useful for needs, and I don't see it being abstract.

If you do consider it abstract (don't ask me the meaning of abstract pls) and mathematical, then wouldnt u have a lot of usele- I mean, a lot of unsolicited functions just like distance as well?
For example, the number of 3d objects in a system could be a function, the edges of shapes in a 3d/2d/1d system could be a function

covert heath
#

(in case any of this is confusing, well... yes. it is.)

valid nimbus
#

there can be a lot of functions

#

just like distance

restive geyser
austere cove
#

good point, what does a function mean to you?

valid nimbus
#

this is something mathematically possible to create a formula of

#

right?

restive geyser
#

In general, what is a function?

austere cove
#

nope

covert heath
#

hooboy

austere cove
valid nimbus
covert heath
#

(something something sets)

restive geyser
#

You're jumping around again

covert heath
#

tell us what a function is

covert heath
valid nimbus
#

why care about measure theory and distance then

valid nimbus
#

a function is

restive geyser
#

-# If they were useless [assuming you mean by this that no one can understand what you mean by these], then they weren't profound to begin with

austere cove
#

@valid nimbus a function is any way of mapping values from an input set (called a domain) to an output set (called a codomain). Any method you can define to do this is valid, you don't need a formula.

covert heath
#

a function is a bijective relation between two sets.

#

okay OE does that better

austere cove
covert heath
#

no?

#

alright i guess

austere cove
covert heath
#

wait ofc not

valid nimbus
covert heath
#

apologies for being dumb

#

just any relation that doesnt map one preimage(?) to 2 images

#

or whatever the fuck the terms are

covert heath
#

11th grade math is wasted on me

valid nimbus
#

mapping values

#

From an input set

covert heath
#

(jee nahi hoga omg jaa raha hoon kuye mein koodne)

restive geyser
#

You could write a thousand pages, but if your premise is wrong (like the definition you'd given for a function), then the rest of your paper, I'm sorry to have to tell you this the hard way, would be bullshit.

valid nimbus
#

this seems like a perfectly fine function then

restive geyser
covert heath
#

what set does it map from

austere cove
#

In set theory, we can define a function as a set of ordered pairs (input, output) such that in the set each value of the input set only appears once.

covert heath
#

yeah thats good

#

why the fuck did i say bijective goddamn

valid nimbus
covert heath
#

i need to get chocolate to stop being dumb

valid nimbus
#

the inputs are same for this

#

u get the distance, u get the area of the 2 objects

covert heath
#

the input is a distance?

steel veldt
#

Is this still going on??????

valid nimbus
covert heath
#

yep

#

welcome

valid nimbus
#

of random functions id consider useless

#

not necessarily distance that's required here

#

see my idea

restive geyser
#

You see, that's not what a distance metric is

valid nimbus
#

why do we specialize distance as a function

austere cove
#

distance is required to set up a euclidean space

valid nimbus
#

and not those ideas

restive geyser
#

A distance metric is a type of function whose OUTPUT is called a distance

#

Not the INPUT(S)

valid nimbus
austere cove
#

if we use a different idea of distance then we get spaces with different properties and different notions of a line

valid nimbus
#

If u read what I said properly

austere cove
#

only a euclidean space has the same idea of a line that we're used to

covert heath
#

'map out the domain'

covert heath
#

please dont use words you dont understand

#

it doesnt help

valid nimbus
#

well so what do u do with this distance then

#

u use it to define a line?

#

Or

#

u use it to describe the line

#

a quality of the line

austere cove
#

So let's say we have two points O and A which define a line

valid nimbus
#

yeah

covert heath
covert heath
valid nimbus
covert heath
#

not the word id use

valid nimbus
austere cove
#

then for any point on the line, let's call it S, we have either d(S, O) = d(S, A) + d(A, O) or some permutation of this

valid nimbus
#

I mean

austere cove
#

and none of these equations are true if S is not on the line

valid nimbus
#

that would give all possible points

#

and yes

#

if any point is not holding true

#

then it's not a part of line

#

hmm

austere cove
#

so now we have defined a line using only our distance metric

valid nimbus
#

I see

austere cove
#

not appealing to any particular coordinate system

valid nimbus
#

well

#

it is kinda disappointing, because without co ordinates, you can't specify those 2 points/objects to be in 3 dimensional space or any space at all

#

or CAN you?

austere cove
#

the idea is we are building a coordinate system from scratch

valid nimbus
#

hmm

#

from scratch

#

so, what is our next step?

#

after determining that, we have a line and 2 points

austere cove
#

to review, we picked O, said it's (0, 0, 0)

valid nimbus
austere cove
#

then we picked A, said it's (1, 0, 0)

valid nimbus
valid nimbus
#

allllright

austere cove
#

next, we pick B, check if it's on the line OA (which we determine using our metric), if it's not on this line, we call it (0, 1, 0)

valid nimbus
#

alright

austere cove
#

Now we pick C, we determine if it's not on the plane OAB

valid nimbus
#

finally we enter relative directions now

austere cove
#

we can still do this using the metric

valid nimbus
#

never mind I mistook u

austere cove
#

if it's not on the plane, we say it's (0, 0, 1)

covert heath
covert heath
#

no words that have meanings in the real world.

#

theyre points.

#

this is not physics

austere cove
#

now we have a complete definition of the coordinate system

#

but it's not "nice"

#

it's not orthonormal

#

our right angles are not right angles, etc.

valid nimbus
#

so essentially

austere cove
#

d(O, A) could be like a million or an irrational number

valid nimbus
#

you just defined basis vectors

austere cove
#

yes

#

and once we have a set of basis vectors, we can use them along with our metric to define a set of orthonormal basis vectors.

valid nimbus
#

that's cool and all but

#

how do u make it nice now

austere cove
#

and once we have that, we have just a regular set of x, y, z axis that you're normally dealing with

valid nimbus
#

if we ignore relativity

#

and we end up here with a different

austere cove
#

In mathematics, particularly linear algebra and numerical analysis, the Gram–Schmidt process or Gram-Schmidt algorithm is a way of finding a set of two or more vectors that are perpendicular to each other.
By technical definition, it is a method of constructing an orthonormal basis from a set of vectors in an inner product space, most commonly...

#

This is how ^

valid nimbus
#

is there a way that u convert these

valid nimbus
#

Hmm

#

that is very interesting

austere cove
#

Note, once you do this, you will have a coordinate system that agrees with your metric, but you can have different equivalent metrics for your space

valid nimbus
#

hold on

austere cove
#

This all depends on your notion of distance. And this is a choice you need to make.

valid nimbus
#

something is not hitting me here

#

you defined basis vectors

#

by oa

#

distance, cool, cool everything is cool

#

but

#

if u were to take

#

another object or a point

#

at any arbitrary location

#

how do you plot it's location?

#

you're not just seeing the imaginary graph and saying it's at that location right? I mean.. theres a lot of error with that

#

is there a function that gives u like the exact position of it

austere cove
#

So we can do so with OABC directly, each point in space is some linear combination of these vectors

valid nimbus
#

of the vector perhaps

#

yeah

#

but how do u know

#

what the combination is

#

I mean.. it's really hard to guess

austere cove
#

it can be, yeah

covert heath
valid nimbus
#

that gives the precise exact answer

#

it seems impossible to guess

austere cove
#

so one thing you seem to need to get comfortable with is a non-constructive proof

valid nimbus
#

what is that

austere cove
#

I can prove to you that every point can be given by a unique combination of vectors, but that doesn't necessarily mean that I can give you a recipe for making each point.

#

just some combination exists, we don't know what it is apriori

valid nimbus
valid nimbus
austere cove
#

ok let's say that you have a nice set of orthonormal axes.

valid nimbus
#

we just have to do so by guessing?

austere cove
#

let's not fuss with how you got them

#

how would you located the point R using your axes?

#

This is the first time I mentioned R to you, and you don't know anything else about R.

valid nimbus
valid nimbus
austere cove
#

ortho meaning perpendicular, normal meaning of length 1.

valid nimbus
#

well to me as a human

#

I would

#

well I mean u have to show me the point and I would numerically try to narrow it down by removing chunks of area around it

#

I would cut and narrow it down into a point

#

visually

#

and calculate it numerically

#

with a scale

#

in regards to the basis vectors

austere cove
#

sure, that's a process that you could do, and you could estimate the point.

#

I could do something similar with my basis vectors.

valid nimbus
#

yeah

#

it's only estimation tho

#

and like thats

#

really approximately rough

austere cove
#

sure, but without knowing more about R, that's as good as you can do

valid nimbus
#

yeah

#

that is

austere cove
#

you can get an arbitrarily small region around R

valid nimbus
#

yeah

austere cove
#

there is some coordinate, but we might not be able to know precisely what that coordinate is.

valid nimbus
#

yeah

austere cove
#

and that's OK

valid nimbus
#

it kinda seems like a limitation

#

of the system

valid nimbus
#

okay?

#

huhhh

austere cove
#

in the sense that it's as good as you can do for any coordinate system, if this is your process.

valid nimbus
#

every answer is like 99.9999...% innacurate tho

austere cove
#

the key is that you can take the limit of this process.

valid nimbus
austere cove
#

to get the exact answer.

valid nimbus
#

I see

#

wait there's

#

an actual process to cutting smaller circles?

#

I can guess it yeah but like

covert heath
#

now we're gonna talk about calculus are we

valid nimbus
#

what if

#

the object is

#

not a point

austere cove
#

just like we can say that pi is just pi, or we can try to numerically approximate it by saying it's 3.141592653589793238...

covert heath
#

blud is gonna get very active any time now

valid nimbus
#

and has like a shape

valid nimbus
cinder thorn
#

NO WAY opencry

valid nimbus
#

for a point we can just narrow it down a lot

covert heath
valid nimbus
#

for a shape, we have to stop at some point

covert heath
#

at least make a different one

#

...later

#

idk unless OE wants to

austere cove
#

I actually need to go soon

covert heath
#

in which case sure ig you got mods on your side

#

ripp

austere cove
#

I mean, it's christmas, I'm alone at home, I have no car and absolutely nothing better to do, sure, I can spend several hours on this I guess.

#

But I do need to go shower.

knotty grail
covert heath
#

just keep it alive for another hour or so until OE comes back

#

how long has it been already

#

blud is def getting VA

austere cove
#

more than 3 hours so far

proud dirge
#

hi

foggy vapor
valid nimbus
knotty grail
valid nimbus
#

with respect to those weird co ordinates

#

of basis vectors

valid nimbus
#

well functions

covert heath
#

theyre not the same thing

valid nimbus
#

yeah

#

take functions

covert heath
#

points and objects are also not the same

valid nimbus
#

well they're kinda same over here

#

u need to find position of a point

#

u need to find position of an object

covert heath
#

basis vectors dont have 'coordinates'

#

etc etc

valid nimbus
#

well yeah

#

I spoke about the weird shape these basis vectors have

#

even though they're all 1,0,0 etc..

#

why do u take everything so literally

covert heath
#

well

#

its maths mate

restive geyser
#

This is the literal subject where nuance seldom has room to exist

wary condor
#

you now know more math than me @valid nimbus ! and you achevied all of that in one day!

#

I commend your endurance.

cinder thorn
#

How many times did we tell you that you need to be precise in your definitions

covert heath
#

please stop the word salad.

#

everything else is fine

valid nimbus
#

thank you

wary condor
valid nimbus
wary condor
valid nimbus
#

but alright

restive geyser
#

sometimes I'm not defining
is precisely the problem, since you're using words whose actual definitions differ to what you MEAN

covert heath
#

and never say 'logics' again

#

please

#

at least use real words

wary condor
#

I'm really impressed how OE was able to do all of this!!!!!!

valid nimbus
covert heath
#

hes fucking omnipotent

#

its in the name

valid nimbus
#

instead of the usual idea of what's right

covert heath
#

'Logics' is not a word.

restive geyser
#

It's more that you're using philosophically loaded words that DO NOT MATCH WHAT YOU MEAN

covert heath
#

There's Logic.

covert heath
#

Which is not related

#

at all

#

well at least not really

valid nimbus
#

I know philosophical logics are something different even though kinda same

covert heath
#

i dont say logically.

valid nimbus
#

but yeah

valid nimbus
#

alright why don't we accept I was at fault and move on!

covert heath
#

it's Logic!!

valid nimbus
#

I need to do something rq

#

I've been sitting here for 7 hours

#

arguing here

wary condor
austere cove
#

be nice

covert heath
#

clever edit

#

take my joy emoji

#

hi OE!

austere cove
wary condor
knotty grail
#

but really huge respect for standing on your own for a third of a day against 10-20 people

austere cove
#

I know one, they're sick 🙁

covert heath
#

hopefully he got something out of this

austere cove
#

I think he did

proud dirge
#

Can this chat be saved as a memorial

knotty grail
#

🫡

covert heath
#

i swear to fucking hell if i hear another 'how do we get coordinates'

wary condor
covert heath
#

ill just ping OE.

wary condor
#

90% of the helpfuls did crashout like 20 minutes in. (not-not-not discluding myself.)

austere cove
#

oh one thing I didn't mention @valid nimbus sorry about the ping.

I mentioned that the choice of metric is a choice, you can also just change the metric, once you have OABC, you can just define a new one based off of the natural coordinates they represent. In other words, OABC is an orthonormal set of basis vectors in the metric you defined based on the coordinates they give.

covert heath
#

im not crashing out i just dont wanna be asked the same blood thing like i could come up with a different answer this time

#

also the word salad

austere cove
#

if this seems strange to you, this is because you're not yet comfortable with the idea that space can be deformed by a linear transform and remains exactly the same afterwards.

#

anyway, I need to go AFK for a bit again

valid nimbus
#

but

#

I thought the major problem now is locating something with that astronomically hard and weird basis vectors

#

that I don't think we would have an intuition of

austere cove
#

locating anything with any basis vectors (without knowledge of exactly where it is a priori) is the hard part

#

but once you know exactly where something is, you can easily and rapidly construct coordinates for it in any basis

valid nimbus
valid nimbus
valid nimbus
#

that mushroom is really hard to know the exact co ordinates of

#

u said something called functions and limits would get me a good answer

#

knowing those functions would be hard tho I'm assuming

austere cove
#

Here's a procedure you can take

#

Consider a bounding box around your point, you located it to a region that has coordinates about (a, b, c) to (a', b', c')

covert heath
austere cove
#

the mushroom is the object lol

valid nimbus
covert heath
#

ah

valid nimbus
#

u have to be really studious to locate it precisely

#

very hard for me personally

covert heath
#

really disturbing imagery lol

austere cove
#

let a > a', b > b', and c > c'

austere cove
#

so we have a point in the middle of this box, ((a + a')/2, (b + b')/2, (c + c')/2) right

valid nimbus
#

how is it a bounding box

austere cove
#

yes, but they define the opposite corners of a box

valid nimbus
#

Oh

#

Opposite corners

#

wait lemme get the imagery of this

#

so

#

u have a box

#

inside that is the object btw

valid nimbus
austere cove
#

that's a 2d box

#

I'm talking about a 3d box

valid nimbus
#

ah well

#

imagine 2 rectanges ok

austere cove
#

or nd in the general case

valid nimbus
#

and tell me for the first rectangle

austere cove
#

anyway

valid nimbus
#

which corner

#

and second rectangle

#

which corner

#

then it's pretty easy to imagine the box

austere cove
#

you have a point in the center of the box

valid nimbus
#

wait

#

would that be

#

at the centre of the object as well

austere cove
#

no

#

your point is somewhere in the box

valid nimbus
#

oh

#

hmm alright

austere cove
#

your object is composed of many points, so you would need to do this procedure for each individual point

valid nimbus
#

now if that's a, b, c

valid nimbus
#

for now

austere cove
#

sure, let's talk about a single point

valid nimbus
#

one point in the box

#

alright

austere cove
#

we don't know where in the box this point is

valid nimbus
valid nimbus
#

well I mean

austere cove
#

(a, b, c) is the top left front corner of the box, and (a', b', c') is the bottom right back corner

valid nimbus
#

ohh yeah

austere cove
#

for relevant definitions of left front etc.

valid nimbus
#

I get it

#

yeah yeah sure

austere cove
#

so you choose some point in the box, and then you can use this point to make 8 smaller boxes inside of the box.

valid nimbus