# Thread: Cunstruction with compasses and ruller

1. ## Cunstruction with compasses and ruller

Are there construction with compasses and ruler of non-Euclidean geometry?
Can I get a link to site of it?

2. ## Re: Cunstruction with compasses and ruller

Originally Posted by policer
Are there construction with compasses and ruler of non-Euclidean geometry?
Can I get a link to site of it?
If you have a computer file, then click the $\boxed{\text{Go Adavanced}}$ tab.
Find and click the $\boxed{\text{Manage Attachments}}$ tab & follow instructions.

3. ## Re: Cunstruction with compasses and ruller

I just what to understand if there is any information about comapasses and ruller in non-Euclidean geometries?
If not, it is o.k.!!!

4. ## Re: Cunstruction with compasses and ruller

Originally Posted by policer
I just what to understand if there is any information about comapasses and ruller in non-Euclidean geometries?
If not, it is o.k.!!!
I am looking at three textbooks in non-Euclidean geometries. No one of which even mention constructions. So I have no idea where you can find material in that topic if it even exists.

5. ## Re: Cunstruction with compasses and ruller

The straight edge, in Euclidean geometry, allows you to construct a line through two given points. The compasses allow you to construct the circle with given center and radius. What figures correspond to "lines" and "circles" in non-Euclidean geometry?

6. ## Re: Cunstruction with compasses and ruller

Althought the use of compasses and ruler in geometry, there is a possibility to use another tools.
In the history of math, there are also different tools that are different from those.
So, if the tools are not ruler and compasses.. you can build with another tools.
Why you are thinking that there are no-notes about it? (In the Internet?)

7. ## Re: Cunstruction with compasses and ruller

Originally Posted by policer
Althought the use of compasses and ruler in geometry, there is a possibility to use another tools.
In the history of math, there are also different tools that are different from those.
So, if the tools are not ruler and compasses.. you can build with another tools.
Why you are thinking that there are no-notes about it? (In the Internet?)
I think you are confusing two notions. For example, in ruler-compass constructions you have a collapsible compass and an unmarked straight edge. So you can't directly mark off a given length on a line and transfer that length to a different line with those tools. In other words, the compass can't be used like a mechanical drawing set of dividers, which hold their setting when lifted from the paper. But, with the ruler and collapsible compass you can effect the same thing with a few construction steps. So, effectively, you can add a set of dividers to your Euclidean toolset.

But your original post asked about tools for non-Euclidean geometry. That's a different thing. It's not my field, but I don't think you have addressed the points raised by HallsOfIvy in post #5.