## Friday, December 07, 2007

### Dumbfounding Dimensions

For the past month or so, Sean has been fascinated with 2-dimensional vs 3-dimensional shapes. He's also been drawing tesselation of shapes. Brian was the one patiently teaching him about tesselation.

He's also asked numerous times for me to teach him to draw spheres, cones, cylinders, cubes, cuboids, pyramids and lately ellipsoid after he asked what a 3-d oval would look like.

Today I was stumped when he asked if a point was one-dimensional. We searched the net and I read that a point was zero-dimensional and lines are one-dimensional.

Brian explains to me what he understands about 1D, 2D and 3D:
"We are in a 3-dimensional world and everything, except shadows I think, is 3-D in our world, but what we view is just 2D. In a 2-dimensional world, what we can only see is a slit or a line, eg if you cut a very thin line on a piece of cardboard and look through it, that's how much you would see in a 2-dimensional world. For a one-dimensional view, you need to take a very very sharp pencil, and use it to make a hole in a piece of paper, that's how much you'll be able to see in a one-dimensional world. Basically, a point is what we see in a one-dimensional world, a line is what we see in 2-dimensional world and a plane is what we see in the 3-dimensional world."

I'll summarise if the above is true:
A point is zero-dimensional;
A line is one-dimensional;
A plane (any shape we draw) is two-dimensional;
And the stuff in our world are three-dimensional.

Please correct us if this is wrong. I think I'm gonna confuse my boys more and more with my incompetence in Science.

Sigh...I still have to find out how to answer Sean's other question, "What does 4-dimensional mean?"...Hellllpppp!

yun said...

Your sons are really very smart for their age (know only Brian's age from the ticker) and into science. The idea I had when you mention "4th dimension" was time. I think I only know that when I am in my 20s lor. And from wiki, the 4D can be not just time.

Lilian said...

Thanks Yun, are you the Yun I emailed my Hkg itinerary template to? Brian's 10 and Sean's 5.

Yeah, I also thought the 4th dimension was time. Even if I live to be a thousand years old, I don't think I'd ever understand all this.

Anonymous said...

hello!

some people believe the fourth dimension is time, while others think of it as the equivalent of what the third dimension is to the second. (that there is an entire world out there)

i personally follow the latter, though i believe it is not within our capabilities to fully comprehand what it really is.

http://tetraspace.alkaline.org/page1.htm

the website above is quite interesting

Lilian said...

Hi Anonymous, thanks for your comment and for the link too, clear explanations there.

Speaking of another entire world, my younger boy asked me just this week if there was such a thing as a parallel universe. Like you said, this is something we could never hope to comprehend and I'm not gonna pretend I know the answer, so I just said, "I don't know."

Drop by again soon!

yun said...

Yes, I am the same Yun. Haha...

Anonymous said...

i'm samantha by the way!

Lilian said...

@yun: So when's your trip to Hkg? Eat lots!

@samantha: Hello Samantha, hope to see you here again :)