Dimensions and Mass
Name: Devdatta H.
Can a thing which has only 2 dimensions have mass? Can we
see it? What about the things which have more than 3 dimensions?
The first thing comes to mind with a two-dimensional object is it cannot
have any atoms. Atoms are three-dimensional objects. Of course, there is
no law that all things must be made of atoms. There is no law that only
three-dimensional objects have mass. Quantum physicists have invented
models for theoretical two-dimensional objects, but I do not know of any
that have ever been really detected. As for "seeing" such an object, I do
not know how it could interact with anything passing through it. Energy
transfer usually requires some distance over which it can occur. A 2-D
object would need light traveling along its surface for our eyes to notice
As for more than three dimensions, such objects do exist, and you are one of
them. The only difference is that our senses don't deal with the fourth
dimension in the same way as the first three. Our senses notice the fourth
dimension as passage of time. We can think of ourselves now, or two days
ago. We can think of ourselves as here, or three feet back. Therwe really
isn't a huge amount of difference. Einstein was the first to notice that in
many ways passage of time behaves a great deal like passage of distance. He
joined them together into a four-dimensional "space-time".
Dr. Ken Mellendorf
This Is Only My Guess:
There is no real, physical, 2-D object. One can
imagine that if it were to exist, it would carry no
4-D objects do not (as far as I know) exist either.
However, I've met people who claimed to be able to
visualize 4-D objects. The University of Illinois in
Urbana-Champaign has a room called The Cave. In
there, images are projected onto all the walls,
allowing participants to see objects in 3-D. With
this room, many professors have been able to use Time
to see the 4th dimension. Note, I said USE Time; Time
is NOT the 4th dimension that many of us believe.
I was given a short lecture on how this actually
works. If you are curious, I can send you a more
detailed letter explaining the concept behind this
rather amazing visualization experiment.
The subject of dimensions has fascinated mankind for centuries. For some
is an answer to your question - an answer assuming the limits of our three
dimensional world. For others the answer resists the limits of our 3D world.
For the first group... 2D objects do not exist in reality, only as illusions
such as a motion picture image on a screen. This group would answer your
question, "No, 2D objects have no mass." This group would also consider the
4th dimension an illusion with the possible exception of time. Height, width,
depth (that's three) and how long it has been there (the 4th).
Other suggest, but have a hard time proving the existence of object that exist
with a different number of dimensions. Perhaps mass is only a property of 3D
objects and objects with varying numbers of dimensions possess other
properties. You might find interesting reading in "Flatland" (sorry, don't
recall the author) that is the story of 2d beings. Or, try reading (a much
tougher read) "Hyperspace" by Kaku who suggests the ultimate existence of 10
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Update: June 2012