Concentric circles are parallel?

In summary, the conversation discusses the concept of parallelism, specifically in relation to lines and curves. The usual definition of parallel in Euclidean geometry only applies to straight lines, but there are other definitions that include curves. The key characteristic of parallelism is maintaining a constant distance between two objects, regardless of whether they are straight lines or curves. However, the understanding of parallelism is limited by humanity's focus on straight lines, making it difficult to understand non-Euclidean geometries. There is a need for a more inclusive definition of parallelism that recognizes its presence in natural phenomena.
  • #141
G037H3 said:
you think that a 'line' is any 1 dimensional continuum, this is not so

all 1 dimensional continuums are curves, and the curves that are perfectly straight (parallel with at least one other straight line, etc.) are called lines
I not too understand.
 
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  • #142
I propose the creation of a new word: "Phyallel!"

The definition of "phyallel"?:_____(insert definition here)______

:-)
 
  • #143
lol :approve:
 
  • #144
Dr Lots-o'watts said:
I propose the creation of a new word: "Phyallel!"

The definition of "phyallel"?:_____(insert definition here)______

:-)

In the analytic geometry,
Supposition
the straight line L1 equation is y=kx,
the straight line L2 equation is y=kx+c,
then L1∥L2 ,
if c→0, then still L1∥L2.
When c=0,
L1 and L2 superposition,
if L1 and L2 not parallel, then L1 and L2 will not superpose, will intersect.
L1 and L2 superpose, not intersect.
Therefore still L1∥L2,
Therefore the straight line own and oneself is parallel, otherwise the straight line will not be a straight line, will intersect.
The curve is also so, the curve is also own and own parallel, therefore the curve is also may mutually parallel.
Does my this logic have what question?
 
  • #145
Your statement that superposed lines do not intersect is incorrect.

If two lines do NOT intersect there is NO point that lies on both lines. That is obviously incorrect for superposed lines.
 
  • #146
So two lines phya-intersect iff they intersect but are unequal.

Has anyone yet figured out what it means to be phya-parallel ("phyallel" as Dr Lots-o'watts puts it)?
 
  • #147
HallsofIvy said:
Your statement that superposed lines do not intersect is incorrect.

If two lines do NOT intersect there is NO point that lies on both lines. That is obviously incorrect for superposed lines.
Your view is also not correct, the superposition is two straight line all corresponding points overlapping, but intersects has a spot superposition, but other spots do not superpose. Therefore the superposition is not the intersection.

“If two lines do NOT intersect there is NO point that lies on both lines” is correct.but the superposition is not the intersection.
 
  • #148
HallsofIvy said:
Your statement that superposed lines do not intersect is incorrect.

If two lines do NOT intersect there is NO point that lies on both lines. That is obviously incorrect for superposed lines.
The intersection is two straight lines has a common point, but superposes is two straight lines becomes a line straight line. Therefore the intersection and the superposition are different.
 
  • #149
I agree with HallsofIvy. If you have two straight lines that are parallel (no intersection points) and you translate one of them so that it coincides with the other line, then the two lines intersect at every point.

No doubt it's a problem with your command of English. "To intersect" does not necessarily mean that the lines have to cross at some nonzero angle.
 
  • #150
Mark44 said:
I agree with HallsofIvy. If you have two straight lines that are parallel (no intersection points) and you translate one of them so that it coincides with the other line, then the two lines intersect at every point.

No doubt it's a problem with your command of English. "To intersect" does not necessarily mean that the lines have to cross at some nonzero angle.

Actually we may regard as a straight line are two superpose in the together straight line, they look like are a straight line, under such situation, these two straight lines was not being parallel? Obviously, although they superpose in together, but they are parallel.
 
  • #151
Mark44 said:
I agree with HallsofIvy. If you have two straight lines that are parallel (no intersection points) and you translate one of them so that it coincides with the other line, then the two lines intersect at every point.

No doubt it's a problem with your command of English. "To intersect" does not necessarily mean that the lines have to cross at some nonzero angle.
The superposition straight line, their included angle is zero mutually, but intersects the straight line, their included angle is not zero. Therefore is different.
 
  • #152
Mark44 said:
I agree with HallsofIvy. If you have two straight lines that are parallel (no intersection points) and you translate one of them so that it coincides with the other line, then the two lines intersect at every point.

No doubt it's a problem with your command of English. "To intersect" does not necessarily mean that the lines have to cross at some nonzero angle.
In the attached figure is an animation, explained that anything is the superposition, any intersection, they are different.
 

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  • #153
The animation clearly shows that when one line is superimposed on another, there are an infinite number of intersection points.
 
  • #154
Mark44 said:
The animation clearly shows that when one line is superimposed on another, there are an infinite number of intersection points.

there are an infinite number of intersection points. ???
 
  • #156
phya said:
there are an infinite number of intersection points. ???

a line is a set of infinite points sharing a value, a two dimensional continuum of those points

if a line has an infinite number of points, and another line merges with the first, then both have an infinite number of points, and an infinite number of intersection points

if you have two lengths of rope that are infinitely long, and place one on top of the other, then there are an infinite number of places you could stick a nail through both ropes o_O
 
  • #157
Let's not use any analogies from real life, or we'll never hear the end of how the ropes can't be truly merged, only touching each other.
 
  • #158
Mentallic said:
Let's not use any analogies from real life, or we'll never hear the end of how the ropes can't be truly merged, only touching each other.

I thought that he would be able to reason that, since we're talking about plane geometry, a distinction in 3 dimensions can't be made, since it is a top-down view...
 
  • #159
Mark44 said:
So you now agree with me and HallsofIvy?

No, I did not agree, I thought in the animation shows the superposition is the parallel one kind, but in animation intersection, is not is parallel.
 
  • #160
Mentallic said:
Let's not use any analogies from real life, or we'll never hear the end of how the ropes can't be truly merged, only touching each other.
:wink:

Actually, after the superposition straight line is a straight line, is two straight lines becomes a straight line, therefore I asked that the straight line is own and oneself is parallel.
 
  • #161
The parallel essence is the distance maintains invariable, but is not the intersection does not intersect. .
 
  • #162
Why? Because you say so?

Parallel is defined as two or more lines that maintain a constant distance between each other and as such, they don't intersect.

Notice: two or more lines.
 
  • #163
Mentallic said:
Why? Because you say so?

Parallel is defined as two or more lines that maintain a constant distance between each other and as such, they don't intersect.

Notice: two or more lines.
Actually, parallel was aims at two lines, the parallel essence was two line distances maintains invariable.
 
  • #164
Mentallic said:
Why? Because you say so?

Parallel is defined as two or more lines that maintain a constant distance between each other and as such, they don't intersect.

Notice: two or more lines.

Parallel aims, a pair, a pair of line.
 
  • #165
phya said:
the parallel essence was two line distances maintains invariable.

Yes, two distinct lines.
 
  • #166
Mentallic said:
Yes, two distinct lines.

But the superposition line is two line special situations,
 
  • #167
Two congruent triangles may superpose a triangle. Two straight lines are congruent, two straight lines may also superpose a straight line.
 
  • #168
Do you realize you've nearly hit 150 posts and most - if not all of it - has consisted of crackpottery?
 
  • #169
phya, geometry is one of those things where you should accept the ideas put forth by the people who created and developed it...the definitions have been argued about for thousands of years and conclusions have been reached based on logical arguments

if you really want to learn geometry, go pick up all three volumes of https://www.amazon.com/dp/0486600882/?tag=pfamazon01-20 and work through it; it explains all of the definitions and ideas in great detail
 
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  • #170
G037H3 said:
phya, geometry is one of those things where you should accept the ideas put forth by the people who created and developed it...the definitions have been argued about for thousands of years and conclusions have been reached based on logical arguments

if you really want to learn geometry, go pick up all three volumes of https://www.amazon.com/dp/0486600882/?tag=pfamazon01-20 and work through it; it explains all of the definitions and ideas in great detail
Yes, the Euclidean geometry already had over a thousand year history, but afterward presented the non-Euclidean geometry, this explained that the geometry is in the development.
 
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  • #171
phya said:
Yes, the Euclidean geometry already had over a thousand year history,

2500 years, and Greek geometry is the first use of rigorous proof in science.

but afterward presented the non-European geometry,

Non-Euclidean or Non-European? Regardless, if you want to learn plane geometry, take my suggestion, a few hours of study will blow your mind.
this explained that the geometry is in the development.

Plane geometry is well understood lol.
 
  • #172
You must acknowledge that parallel is the distance maintains invariable, because the distance has changed, therefore only will then intersect. The concentric circle and straight line parallel is similar, they are the distance maintain invariable. Whether you do acknowledge this point?
 
  • #173
In Europe, the supposition we give human's definition are “the white skin biology”, afterward Columbus's ship to the Americas, the crews has discovered some living thing, is similar with the human, but their skin is the black, therefore the crews had the argument, the most people had thought that these living thing were not the human, because they did not conform to human's definition, most only might call them the kind of human biology, but the small number of people believed that these living thing were also the human, was only their skin's color is different.
Are we about the parallel line question argument are also so?
 
  • #174
phya said:
In Europe, the supposition we give human's definition are “the white skin biology”, afterward Columbus's ship to the Americas, the crews has discovered some living thing, is similar with the human, but their skin is the black, therefore the crews had the argument, the most people had thought that these living thing were not the human, because they did not conform to human's definition, most only might call them the kind of human biology, but the small number of people believed that these living thing were also the human, was only their skin's color is different.
Are we about the parallel line question argument are also so?

That's 100% wrong. Europeans have known of the swarthy races (subspecies) for a very long time. Aryan invasion of India? was at least 3,500 years ago.

If you don't want to actually study the nature of the things you're talking about, fine. But don't try to change standard definitions to suit your opinion when there is material available for you to study so you can understand why things are labeled as they are.
 
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  • #175
So all you're hoping in doing is that you'll make a contribution to mathematics somehow? You need a reputation first, and that is to know that specific topic inside out.

There is a reason we coined the term crackpot to describe those that suggest new crazy far out theories in science with little to no math ability or even a respectable knowledge in the topic at hand. If you just looked at all the crackpot theories in relativity...

And judging by some of your ideas, mainly that the absolute of a number is an "unsigned" number and not positive because that is being prejudice, then I can only suggest that you put your theories away in the basement, study the maths for many years to come - particularly geometry. It will give you the time to fully appreciate what the collective thinking of millions of mathematics over thousands of years have been able to produce - and once you're grown ripe in age and have a firm position in the understanding of modern geometry, take a look at those dusty old tomes again that you threw into the basement. See if those theories are still sound, and if they are, pursue them further with your new status of being a professional in that topic.
 
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