Does 'Isolated' and 'Free' Mean the Same in Physics Context?

  • Context: Undergrad 
  • Thread starter Thread starter grzz
  • Start date Start date
  • Tags Tags
    Mean
Click For Summary

Discussion Overview

The discussion revolves around the terminology used in physics, specifically whether the terms 'isolated' and 'free' convey the same meaning when describing particles. Participants explore the implications of these terms in various contexts, including theoretical and conceptual considerations.

Discussion Character

  • Conceptual clarification, Debate/contested

Main Points Raised

  • One participant questions if the phrase ‘an isolated free particle’ is redundant, suggesting that the terms may imply each other.
  • Another participant acknowledges the potential for redundancy but argues that natural language's imprecision justifies the use of both terms.
  • A different participant speculates on whether Dirac would have used the phrase, indicating a historical or theoretical perspective.
  • One participant asserts that there is no redundancy, providing examples such as an ion in an ion trap, which is isolated but not free, and electrons in a free electron laser, which are free but not isolated. They define 'isolation' as the absence of interaction with the environment and 'free' as unrestricted motion.

Areas of Agreement / Disagreement

Participants express differing views on whether 'isolated' and 'free' are redundant, with no consensus reached on the matter.

Contextual Notes

Participants rely on specific examples to illustrate their points, which may depend on the definitions of 'isolation' and 'freedom' in different physical contexts.

grzz
Messages
1,036
Reaction score
28
Is there redundancy in the phrase ‘an isolated free particle’?

Do not the words ‘free’ and ‘isolated’ imply each other?

Any help is much appreciated.

Thanks
 
Physics news on Phys.org
grzz said:
Is there redundancy in the phrase ‘an isolated free particle’?
Do not the words ‘free’ and ‘isolated’ imply each other?

Perhaps they should, but natural language is sufficiently imprecise that we're better off with a bit of redundancy.
 
Thanks Nugatory.

I wonder whether Dirac would have used the phrase ‘an isolated free particle’!
 
No, I don't think there is redundancy.
E.g. an ion in an ion trap can be extremely well isolated from the environment but you could hardly refer to it as "free".
The electrons in a free electron laser are (obviously) free, but since they are radiating they are not isolated.

I think of "isolation" as referring to the absence of interaction with the environment, whereas "free" means that the motion of the object itself is not restricted.
 

Similar threads

  • · Replies 1 ·
Replies
1
Views
757
  • · Replies 8 ·
Replies
8
Views
4K
  • · Replies 5 ·
Replies
5
Views
2K
  • · Replies 17 ·
Replies
17
Views
3K
  • · Replies 26 ·
Replies
26
Views
3K
  • · Replies 3 ·
Replies
3
Views
2K
Replies
9
Views
2K
  • · Replies 5 ·
Replies
5
Views
2K
  • · Replies 22 ·
Replies
22
Views
4K
  • · Replies 116 ·
4
Replies
116
Views
4K