1. Hey! We know that a point has 0 dimensions - no height, no length, no width and also no area. If it has nothing in it, how do we know that it is something?
I mean, if it has no dimensions and no area, how are we able to identify it(or roughly, see it) ?? What is the THING that it has, which makes it something? (Apart from length, width and height)....

2.

3. Originally Posted by Gaurav(-26.7)
how are we able to identify it(or roughly, see it) ?? What is the THING that it has, which makes it something?
Location.
That's all it has.

4. Originally Posted by Dywyddyr
Originally Posted by Gaurav(-26.7)
how are we able to identify it(or roughly, see it) ?? What is the THING that it has, which makes it something?
Location.
That's all it has.
Is "location" relative?

5. To what?
We usually (in geometry) define a point (arbitrarily1) and work from there (IOW everything else is "relative" to that point).

1 So long as it's on the paper!

6. Do you have a point to make?

7. Originally Posted by Dywyddyr
To what?
We usually (in geometry) define a point (arbitrarily[sup1[/sup]) and work from there (IOW everything else is "relative" to that point).

1 So long as it's on the paper!
To a frame of reference? If A is moving wrt B is a point as seen by A different to the same point as seen by B?

These point particles are not just geometric entities are they? They have a "physical" reality ,don't they ?(am I just shamelessly displaying my ignorance?)

8. Originally Posted by MacGyver1968
Do you have a point to make?
Where should I put it?

https://4.imimg.com/data4/IS/BD/MY-2...in-250x250.jpg

9. Originally Posted by MacGyver1968
Do you have a point to make?
It's not too late to put you back in the box you know!

10. Originally Posted by geordief
To a frame of reference? If A is moving wrt B is a point as seen by A different to the same point as seen by B?
How can you have a "frame of reference" without defining a "start point"?
If A is moving and defines a point then, surely, that point is defined as (for example) 1 metre from my geometric centre (or 1 metre from the aft-most extremity of my body), in which case that point is already relative to a previously-defined point.
But both A and B can agree on where the point is (although for B it's a moving point...)

These point particles are not just geometric entities are they? They have a "physical" reality ,don't they ?(am I just shamelessly displaying my ignorance?)
They're as physical as "lines". I.e. no. They have no spacial extent, no mass, nothing but location.

11. Originally Posted by Dywyddyr
Originally Posted by geordief
To a frame of reference? If A is moving wrt B is a point as seen by A different to the same point as seen by B?
How can you have a "frame of reference" without defining a "start point"?

Agreed(I was wondering about the other points in relation to that starting point)

If A is moving and defines a point then, surely, that point is defined as (for example) 1 metre from my geometric centre (or 1 metre from the aft-most extremity of my body), in which case that point is already relative to a previously-defined point.
But both A and B can agree on where the point is (although for B it's a moving point...)

These point particles are not just geometric entities are they? They have a "physical" reality ,don't they ?(am I just shamelessly displaying my ignorance?)
They're as physical as "lines". I.e. no. They have no spacial extent, no mass, nothing but location.

It seems strange to have the term "point particle" if they are not physical but I realize I would need to learn about the subject to comment (I do now think I now that "particle" is not what I thought it was when I was at school)

12. Originally Posted by geordief
It seems strange to have the term "point particle" if they are not physical but I realize I would need to learn about the subject to comment (I do now think I now that "particle" is not what I thought it was when I was at school)
Ah.
"In the Standard Model, elementary particles are represented for predictive utility as point particles."
"A point particle (ideal particle[1] or point-like particle, often spelled pointlike particle) is an idealization of particles heavily used in physics."

13. I always thought of it like a zero, a beginning point. No real anything, just a place to start from. The point where negative turns to positive......Does that sound right?

14. Originally Posted by zinjanthropos
I always thought of it like a zero, a beginning point. No real anything, just a place to start from. The point where negative turns to positive......Does that sound right?
Point particles are concerned with physics. The Cartesian plain is composed of an infinitude of geometric points. In the Cartesian plain there is a single origin point, and it is at the orthogonal axis of the abscissa and ordinate lines and has coordinates (0,0).

 Bookmarks
##### Bookmarks
 Posting Permissions
 You may not post new threads You may not post replies You may not post attachments You may not edit your posts   BB code is On Smilies are On [IMG] code is On [VIDEO] code is On HTML code is Off Trackbacks are Off Pingbacks are Off Refbacks are On Terms of Use Agreement