De broglie wavelength and lorentz contraction

Click For Summary
SUMMARY

The discussion clarifies that the de Broglie wavelength, represented by the formula λ = h/p, does not explain the relativistic contraction of matter. While it is true that as the velocity of a particle, such as a proton, increases, its momentum also increases, leading to a smaller wavelength, this phenomenon is distinct from Lorentz contraction. The length contraction formula, lcontracted = l0/γ, where γ = 1/√(1 - v²/c²), describes the behavior of length at relativistic speeds. The de Broglie wavelength is valid in both relativistic and non-relativistic contexts, and the concept of "proper length" does not apply to particles at rest.

PREREQUISITES
  • Understanding of quantum mechanics, specifically de Broglie wavelength
  • Familiarity with special relativity and Lorentz contraction
  • Knowledge of momentum and its relationship with velocity
  • Basic grasp of wave mechanics and frequency concepts
NEXT STEPS
  • Study the implications of the de Broglie wavelength in quantum mechanics
  • Explore the derivation and applications of Lorentz contraction
  • Investigate the relationship between momentum and velocity in relativistic contexts
  • Examine the effects of frequency changes on wave properties at high velocities
USEFUL FOR

Students and professionals in physics, particularly those focusing on quantum mechanics and relativity, will benefit from this discussion. It is also relevant for researchers exploring the intersection of wave mechanics and relativistic effects.

serp777
Messages
117
Reaction score
6
Am I correct in thinking that the quantum mechanical de broglie wavelength explains relativity's contraction of matter? because lambda = h/p, as the velocity of say a proton increases, the momentum also increases, and the wavelength should get smaller because lim p-->infinity of h/p = 0. At very high velocities near light, the distance between amplitude peaks should shrink very close to the Planck length, and appear as a wall.
 
Physics news on Phys.org
Qualitatively, the de Broglie wavelength indeed shrinks when particle increases velocity. However, this has nothing to do with relativity, because actually the formula for length contraction is

[tex] l_{contracted} = \frac{l_0}{\gamma},[/tex]

where [itex]\gamma=\frac{1}{\sqrt{1-\frac{v^2}{c^2}}}[/itex]. When the rod is at rest, the rod still has length, [itex]l_0[/itex], which is a finite number.

The de Broglie formula gives

[tex] \lambda = \frac{h}{\gamma m v},[/tex]

which is different function of velocity than the length in Lorentz contraction. Also, there is no "proper length" which the particle would have at rest. Rather, if the particle is at rest, there is no wave, or in other words, the wavelength is infinite.

The de Broglie formula is valid even in non-relativistic wave mechanics; so it seems this shrinking of the wavelength is not relativistic phenomenon.
 
I think you would need to consider the effects of both [itex]\lambda[/itex] wavelength and frequency changes with velocity to arrive at the cumulative effect on both length and time metrics.
 

Similar threads

  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 6 ·
Replies
6
Views
3K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 28 ·
Replies
28
Views
6K
  • · Replies 6 ·
Replies
6
Views
2K
  • · Replies 14 ·
Replies
14
Views
3K
  • · Replies 17 ·
Replies
17
Views
5K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 28 ·
Replies
28
Views
8K