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mathslover Group TitleBest ResponseYou've already chosen the best response.0
yes a point is dimensionless
 2 years ago

zepp Group TitleBest ResponseYou've already chosen the best response.6
0D = Dot 1D = Line 2D = Plane 3D = Solid 4D = Spacetime 5D = ...idk :P
 2 years ago

abdul_shabeer Group TitleBest ResponseYou've already chosen the best response.0
Then how does it make a line?
 2 years ago

zepp Group TitleBest ResponseYou've already chosen the best response.6
What do you mean?
 2 years ago

zepp Group TitleBest ResponseYou've already chosen the best response.6
. < This is not a point, it's just a representation because a point has no height, no length, no thickness.
 2 years ago

zepp Group TitleBest ResponseYou've already chosen the best response.6
One dimension: A line, numbers, they have only a length;
 2 years ago

zepp Group TitleBest ResponseYou've already chosen the best response.6
2D: Shape, Length and width 3D: Solids, Length, width and thickness
 2 years ago

abdul_shabeer Group TitleBest ResponseYou've already chosen the best response.0
What is the definition for a line?
 2 years ago

zepp Group TitleBest ResponseYou've already chosen the best response.6
4D Spacetime: 3 dimentional object travelling/moving through time and space.
 2 years ago

zepp Group TitleBest ResponseYou've already chosen the best response.6
Straight objects without depth and width.
 2 years ago

abdul_shabeer Group TitleBest ResponseYou've already chosen the best response.0
Is it made of many points?
 2 years ago

zepp Group TitleBest ResponseYou've already chosen the best response.6
Um, you can see it that way :)
 2 years ago

abdul_shabeer Group TitleBest ResponseYou've already chosen the best response.0
When a point has no dimension then how can a collection of points make a line?
 2 years ago

zepp Group TitleBest ResponseYou've already chosen the best response.6
A point has no length, depth, width, when you align then, you just created a length
 2 years ago

TuringTest Group TitleBest ResponseYou've already chosen the best response.5
take a point and send it in some direction through space the path that it traces out is a line the real number line is infinitely dense so now we are getting into some of the trickyness of infinity
 2 years ago

TuringTest Group TitleBest ResponseYou've already chosen the best response.5
dw:1341410594698:dwhere is the real number line (still a line, consisting of infinitely many points) I can ask you to pick out the point 1
 2 years ago

TuringTest Group TitleBest ResponseYou've already chosen the best response.5
dw:1341410679112:dwand there it is I can also ask you to find numbers between numbers so if I ask you to find 1.5 it should be on the line
 2 years ago

abdul_shabeer Group TitleBest ResponseYou've already chosen the best response.0
My doubt is when a point has zero dimension, then how can it make a line that has one dimension?
 2 years ago

TuringTest Group TitleBest ResponseYou've already chosen the best response.5
dw:1341410742343:dwsimilarly I can keep asking you to find points between the two we have already found 1.75 must be on the line 1.85 1.8 1.8243574687654365768.... etc. must all be on the line therefore there are infintiely many points on a line
 2 years ago

TuringTest Group TitleBest ResponseYou've already chosen the best response.5
between any two points there are infinitely many numbers, do you agree?
 2 years ago

TuringTest Group TitleBest ResponseYou've already chosen the best response.5
like between 1 and 2 are there not an infinity of numbers?
 2 years ago

abdul_shabeer Group TitleBest ResponseYou've already chosen the best response.0
Though there are infinitely many points, each has zero length, zero breadth etc.
 2 years ago

TuringTest Group TitleBest ResponseYou've already chosen the best response.5
but you are trying to add an infinity of infinitely tiny lengths!\[\infty\cdot\frac1\infty=\text{undefined}\]you can't treat infinity like a number and perform addition on it; it is a concept, rather than a number.
 2 years ago

TuringTest Group TitleBest ResponseYou've already chosen the best response.5
it would require an infinity of points lined up in a row, and they still would have not length this may seem paradoxical, but it reflects the infinite density of number distribution on the real line, so it is not trivial
 2 years ago

abdul_shabeer Group TitleBest ResponseYou've already chosen the best response.0
Wouldn't 0+0+0+0........ be zero?
 2 years ago

TuringTest Group TitleBest ResponseYou've already chosen the best response.5
no, because \(0\cdot\infty\) is undefined
 2 years ago

TuringTest Group TitleBest ResponseYou've already chosen the best response.5
again, I know this does not make instinctive sense infinity is a tricky topic that has driven many mathematicians mad!
 2 years ago

abdul_shabeer Group TitleBest ResponseYou've already chosen the best response.0
When 0*infinity is undefined, then how does it produce a length?
 2 years ago

TuringTest Group TitleBest ResponseYou've already chosen the best response.5
because you don't have to build a line one point at a time; it's a mathematical construct that contains infinitely many points
 2 years ago

TuringTest Group TitleBest ResponseYou've already chosen the best response.5
if there were some finite number of points that you could put together to make a line, then the real number line would not be infinitely dense (i.e. some points would be missing from the line because there would have to be a limit on the number of times I can tell you to find the midpoint between two points)
 2 years ago

TuringTest Group TitleBest ResponseYou've already chosen the best response.5
dw:1341411610187:dwtake any line segment; I want the midpoint (whatever it is)
 2 years ago

TuringTest Group TitleBest ResponseYou've already chosen the best response.5
dw:1341411643038:dwnow I want the midpoint of the right half
 2 years ago

TuringTest Group TitleBest ResponseYou've already chosen the best response.5
dw:1341411666632:dwnow again, the midpoint of the right half
 2 years ago

TuringTest Group TitleBest ResponseYou've already chosen the best response.5
dw:1341411687412:dwwe could do this forever, right? that means there are infinitely many points on that line; I can always ask you to find the midpoint between any two points.
 2 years ago

TuringTest Group TitleBest ResponseYou've already chosen the best response.5
yet even though it is an infinity of points, they only add up to a finite line segment, so an infinity of things can add to something finite. Reference to Zeno's paradox.
 2 years ago

abdul_shabeer Group TitleBest ResponseYou've already chosen the best response.0
What does "though it is an infinity of points, they only add up to a finite line segment" mean?
 2 years ago

zepp Group TitleBest ResponseYou've already chosen the best response.6
TuringTest just showed that there's an amount of point between two point, but when this infinite adds up, it gives something finite, something you can just count on your fingers.
 2 years ago

zepp Group TitleBest ResponseYou've already chosen the best response.6
an infinite amount*
 2 years ago

abdul_shabeer Group TitleBest ResponseYou've already chosen the best response.0
How can infinite things add and give some finite value?
 2 years ago

nbouscal Group TitleBest ResponseYou've already chosen the best response.0
It is important to understand here that points and lines are simply geometric realizations of abstract concepts. As mentioned earlier, a . is not a point, nor is a drawing of a line actually a line. A point takes up no space, so it can't be shown, and similarly a line can't be shown because it has no height. Even a plane can't be shown really, because it has no depth. So, when you're asking these questions, it is best to avoid relying too heavily on your geometric interpretation of the concepts. Instead, it is better to look at them using the tools of analysis. TuringTest is referring to some relevant results of analysis, for example, the uncountability of the real line. Not only is the real line infinite in the number of points, it is uncountably infinite. This ends up implying that the number of points between 0 and 1 is actually the same as the number of points on the entire real line. So, to interpret this somewhat geometrically, you can zoom in as close as you would like to the real line and still be looking at the same number of points. Of course, this doesn't work like any realworld object. Another relevant way of looking at the real line is through the lens of topology. We can talk about the real line as a metric space, and we define the metric abstractly. We simply define how distance works. One sees by learning some introductory topology that the real line is actually just one way to look at the set of real numbers, and there are many others. So, this is another way to look at the problem.
 2 years ago

TuringTest Group TitleBest ResponseYou've already chosen the best response.5
in answer to how an infinity of things can add up to something finite do you know what an infinite series is @abdul_shabeer ?
 2 years ago

abdul_shabeer Group TitleBest ResponseYou've already chosen the best response.0
No @TuringTest
 2 years ago

zepp Group TitleBest ResponseYou've already chosen the best response.6
The sum of all terms of the geometric sequence that halves each time would be the perfect example :D
 2 years ago

TuringTest Group TitleBest ResponseYou've already chosen the best response.5
\[\sum_{n=1}^\infty(\frac12)^n=\frac12+\frac14+\frac18+...=1\]when you study them this may make a little more sense the one above can be said to represent Zeno's paradox
 2 years ago

nbouscal Group TitleBest ResponseYou've already chosen the best response.0
In general, we don't have an infinity of things simply "adding up" to finite value. We have an infinity of things approaching a limit that has finite value.
 2 years ago

asnaseer Group TitleBest ResponseYou've already chosen the best response.0
Hey guys  I'm at work at the moment but spotted this discussion and remembered a thread I saw that might help explain this to to you @abdul_shabeer : http://mathforum.org/library/drmath/view/55297.html Hope it helps  back to work now... :)
 2 years ago

UnkleRhaukus Group TitleBest ResponseYou've already chosen the best response.0
dw:1341412717556:dw
 2 years ago