Does the length of a string depend on it's energy?

Click For Summary

Discussion Overview

The discussion centers around the relationship between the length of a string and its energy, as well as the relationship between the area of a d-brane and its energy. Participants explore whether one quantity depends on the other or vice versa, raising questions about the nature of these relationships.

Discussion Character

  • Exploratory, Debate/contested, Conceptual clarification

Main Points Raised

  • Some participants question whether the length of a string depends on its energy or if the energy depends on the length.
  • Others introduce the idea that if x(y) is a function of y, then y(x) is also a function of x, provided the function is single-valued.
  • A participant clarifies that there is a distinction between a function without an explicit expression and a relation that does not map arguments to values.
  • There is a suggestion that the discussion may not be worth pursuing further, indicating a potential disagreement on the relevance of the argument about functions and relations.

Areas of Agreement / Disagreement

Participants express differing views on the nature of the relationships between length and energy, with no consensus reached on the fundamental questions posed.

Contextual Notes

Some assumptions about the nature of functions and relations are not fully explored, and the discussion does not resolve the implications of these relationships.

Nickyv2423
Messages
46
Reaction score
3
Does the length of a string depend on its energy, or does its energy depend on its length? Similarly, does the area of a d brane depend on its energy, or does its energy depend on its energy?
Are these stupid questions?
 
Physics news on Phys.org
Well, if x(y) is a function of y, then y(x) is a function of x, whether you can explicitly write it down or not :P
 
haushofer said:
Well, if x(y) is a function of y, then y(x) is a function of x,

If the function is single valued, at least (which of course it is in the OP's question). Otherwise one gets a relation, not a function.
 
That's what I meant by the part you left out.
 
haushofer said:
That's what I meant by the part you left out.

Okay. To me there is a difference between a function that has no "explicit expression" (say the Gauss error function), and a relation which simply does not map arguments to values at all. But anyway, it's not worth arguing about this much further here.
 

Similar threads

Undergrad Unifying string theory and loop quantum gravity
  • · Replies 2 ·
Replies
2
Views
5K
Undergrad String Basics question from an ABJECT ignoramus
  • · Replies 4 ·
Replies
4
Views
2K
Graduate Can strings increase length without changing their energy?
  • · Replies 6 ·
Replies
6
Views
2K
High School On a basic level why aren't loops ##\equiv## strings?
  • · Replies 4 ·
Replies
4
Views
3K
Graduate Basic Scheme and Fundamental Equations of String Theory
  • · Replies 26 ·
Replies
26
Views
4K
Undergrad Why don't strings have a Planck mass?
  • · Replies 7 ·
Replies
7
Views
4K
High School Size of strings in string theory
  • · Replies 11 ·
Replies
11
Views
4K
Undergrad String theory in 4 dimensions?
  • · Replies 2 ·
Replies
2
Views
3K
Undergrad Brane cosmology without string theory?
  • · Replies 1 ·
Replies
1
Views
2K
Undergrad String theory vs Quantum field theory
  • · Replies 1 ·
Replies
1
Views
3K