• Support PF! Buy your school textbooks, materials and every day products via PF Here!

4th dimension?

  • Thread starter hafiz ns
  • Start date
16
0
1. Homework Statement
is there a 4th dimension. if yes can anyone explain it ?


2. Homework Equations


3. The Attempt at a Solution
4th dimension includes time also am i right ? which is X,Y,Z + time
 

HallsofIvy

Science Advisor
Homework Helper
41,709
876
Do you understand what a "dimension" is? A "dimension", in a given problem, is just a number you use to specify all the conditions of the problem. If I were doing a geometry problem connected with spheres of different radii with centers at different points in space, to identify a specific such sphere, I would have to give the three coordinates of its center and its radius- four numbers so this is a "four dimensional" problem. If I were doing a problem involving points in the plane, I might set up an xy coordinate system and label each point by its x and y coordinates- two dimensions because two numbers. If I were doing a problem involving points in "R3" I would set up a coordinate system with x, y, and z axes and every point would be labeled by (x, y, z)- three numbers so three dimensions.

In physics, we are concerned with "events"- things that happen at a particular point in space at a particular time. We require three numbers (coordinates) to identify the point and one number to identify the time. In that sense we are working with four dimensions. Of course, which is the "first", "second", "third", or "fourth" dimension is purely conventional.
 
16
0
thanks hallsofivy ...
 
Also, you could plot a four dimensional point using a constantly changing graph, say, point A's coordinates are 1 by 2 by 3 by 4, which could mean the x is one, the y is 2, and the z is 3 after 4 seconds have passed. Graphing functions like this also works.
 

Want to reply to this thread?

"4th dimension?" You must log in or register to reply here.

Related Threads for: 4th dimension?

  • Posted
Replies
2
Views
1K
  • Posted
Replies
1
Views
297
  • Posted
Replies
8
Views
959
Replies
1
Views
11K
  • Posted
Replies
2
Views
837
Replies
1
Views
8K
Replies
2
Views
2K
Replies
4
Views
947

Physics Forums Values

We Value Quality
• Topics based on mainstream science
• Proper English grammar and spelling
We Value Civility
• Positive and compassionate attitudes
• Patience while debating
We Value Productivity
• Disciplined to remain on-topic
• Recognition of own weaknesses
• Solo and co-op problem solving
Top