Noncommuting position variables due to quantum gravity

Click For Summary
SUMMARY

The discussion centers on the implications of quantizing gravity, specifically addressing the concept of the Planck length as the smallest measurable scale. It asserts that in quantum gravity, the position of a particle cannot be defined at a single point but rather within a neighborhood defined by the Planck length, leading to noncommuting position variables. The operators X, Y, and Z are identified as noncommuting, necessitating that [X,Y] is not equal to zero. The conversation references the paper "Noncommutative Field Theory" by Michael R. Douglas and Nikita A. Nekrasov, which explores the generalization of field theory in the context of noncommuting coordinates.

PREREQUISITES
  • Understanding of Quantum Mechanics principles
  • Familiarity with the concept of the Planck length
  • Basic knowledge of noncommutative algebra
  • Awareness of M theory and string theory frameworks
NEXT STEPS
  • Study the implications of the Planck length in quantum gravity
  • Explore noncommutative geometry and its applications in physics
  • Read "Noncommutative Field Theory" by Michael R. Douglas and Nikita A. Nekrasov
  • Investigate the relationship between quantum Hall states and noncommutative field theories
USEFUL FOR

Physicists, researchers in quantum gravity, and students of theoretical physics interested in the intersection of quantum mechanics and gravitational effects.

nabil0
Messages
20
Reaction score
1
I've read that if one wants to quantize gravity , there must be a smallest length scale " The Planck length " . If I want to measure the position of a point particle then in conventional Quantum mechanics I'll find it at the point $(x,y,z)$ at some-time $t$ with an arbitrary momentum but this can't be though in quantum gravity since the smallest length scale that can exist is the Planck scale so the particle must be at a neighbourhood of (x,y,z) of area that's equal to Planck length . So if we measured the X operator to find the eigenvalue x the particle must be spread in the eigenspace of the Y and Z operators that's X,Y,Z are not commuting operators So we must have [X,Y] not equal to zero .
Is this line of reasoning correct ? Have something of this sort been worked out ? It seems that many things in Quantum mechanics should be modified if we want to incorporate gravitational effects
 
Physics news on Phys.org
http://arxiv.org/abs/hep-th/0106048
Noncommutative Field Theory
Michael R. Douglas (Rutgers, IHES), Nikita A. Nekrasov (IHES, ITEP)
We review the generalization of field theory to space-time with noncommuting coordinates, starting with the basics and covering most of the active directions of research. Such theories are now known to emerge from limits of M theory and string theory, and to describe quantum Hall states. In the last few years they have been studied intensively, and many qualitatively new phenomena have been discovered, both on the classical and quantum level.
 
Sounds interesting . What mathematical knowledge required to be able to understand that paper ?
 
Last edited:

Similar threads

  • · Replies 1 ·
Replies
1
Views
3K
  • · Replies 5 ·
Replies
5
Views
3K
  • · Replies 26 ·
Replies
26
Views
6K
  • · Replies 1 ·
Replies
1
Views
3K
  • · Replies 7 ·
Replies
7
Views
3K
  • · Replies 16 ·
Replies
16
Views
7K
  • · Replies 15 ·
Replies
15
Views
6K
  • · Replies 105 ·
4
Replies
105
Views
16K
  • · Replies 1 ·
Replies
1
Views
4K
  • · Replies 12 ·
Replies
12
Views
3K