Register to reply

3D angles- can they exist?

by fromage
Tags: angles, exist
Share this thread:
fromage
#1
Feb12-13, 07:33 AM
P: 2
i would like to know if the 'angle' between lets say the walls of a room (ie. the intersection of 3 planes all perpendicular to each other) can be represented in mathematical terms, but as a kind of 3D angle- that is to say not as a combination of 2D angles but as an altogether new form of representing the gap between intersecting planes.
Is there any way to do this and if not why can't these 'angles' be represented in 3D?
Phys.Org News Partner Science news on Phys.org
Wildfires and other burns play bigger role in climate change, professor finds
SR Labs research to expose BadUSB next week in Vegas
New study advances 'DNA revolution,' tells butterflies' evolutionary history
Simon Bridge
#2
Feb12-13, 08:22 AM
Homework
Sci Advisor
HW Helper
Thanks
Simon Bridge's Avatar
P: 12,488
Welcome to PF;
Look up "solid angle".
dkotschessaa
#3
Feb12-13, 08:46 AM
dkotschessaa's Avatar
P: 598
Cool, Simon.

I'm in Linear Algebra right now, so correct me if I'm wrong... But isn't this also what we are talking about with certain linear transformations, which can be rotations in any number of dimensions?

-Dave K

HallsofIvy
#4
Feb12-13, 09:11 AM
Math
Emeritus
Sci Advisor
Thanks
PF Gold
P: 39,363
3D angles- can they exist?

No, a "solid angle" is NOT a rotation in three dimensions, any more than a regular angle is a rotation in two dimensions. You can use an angle, in two dimensions to define a rotation but you will also need to specify a point to rotate about. You can use a solid angle to define a rotation but in three dimensions, you will need to specify a point to rotate about and an axis of rotation.
Simon Bridge
#5
Feb12-13, 09:00 PM
Homework
Sci Advisor
HW Helper
Thanks
Simon Bridge's Avatar
P: 12,488
"angle" is one of those concepts you use, almost unconsciously, without really thinking about what it is. Looking at the "similar threads" section (below the "quick reply" box) there is a lot of discussion. You should look up the terms and then read some of the other threads.

Like HallsofIvy points out, it can be important to distinguish the thing from it's uses.
When you want to extend an idea that works in 2 or 3 dimensions, into 4 or more, then you really need to be clear about what the idea embodies.


Register to reply

Related Discussions
Obvious question on angles and solid-angles Differential Geometry 1
Cogito ergo sum,.. however, I dont know you exist, prove to me you exist General Discussion 31
Converting angles in to degree to angles in radians Introductory Physics Homework 2
Do mathematical proofs exist, of things that we are not sure exist? Math & Science Software 43
Refrence Angles & Positive/Negative Angles(Coterminals) HOW? Introductory Physics Homework 1