B Does tunneling affect the energy of a particle in a finite box?

  • B
  • Thread starter Thread starter houlahound
  • Start date Start date
  • Tags Tags
    Energy Particle
houlahound
Messages
907
Reaction score
223
using alpha decay as a concrete example is the energy of the alpha inside and outside the nucleus the same. it appears so from what I can see but alphas do have a range of energies usually up to between 4 - 9Mev. which is the same range as inside the nucleus.

my question really is does tunnelling for say a particle in a finite box to out of the finite box change the kinetic energy of the particle in any situation, always or never?

the formula for tunnelling probability does not supply info on the energy of the tunnelled particle ie from hyperphysics (simple solution);

upload_2016-10-25_8-17-51.png


how would one calculate the energy/frequency of the wave function for the tunnelled particle?
 
Physics news on Phys.org
Energy is conserved, but the potential inside in general won't match the potential outside.

"The energy of the alpha nucleus inside the nucleus" is not really a well-defined concept. You can use this as heuristics, but there are not physically two protons and two neutrons together bouncing around.
 
thanks mfb, so if energy is conserved the particle does have the same energy on the outside implying there is no loss of energy passing through the barrier?

if as mostly does a gamma is also emitted will the gamma energy reduce the alpha particle kinetic energy?
 
houlahound said:
thanks mfb, so if energy is conserved the particle does have the same energy on the outside implying there is no loss of energy passing through the barrier?
Sure.
Its kinetic energy will be different if the potential is different, the total energy is conserved.
houlahound said:
if as mostly does a gamma is also emitted will the gamma energy reduce the alpha particle kinetic energy?
Sure. Same concept: total energy is conserved.
 
Insights auto threads is broken atm, so I'm manually creating these for new Insight articles. Towards the end of the first lecture for the Qiskit Global Summer School 2025, Foundations of Quantum Mechanics, Olivia Lanes (Global Lead, Content and Education IBM) stated... Source: https://www.physicsforums.com/insights/quantum-entanglement-is-a-kinematic-fact-not-a-dynamical-effect/ by @RUTA
If we release an electron around a positively charged sphere, the initial state of electron is a linear combination of Hydrogen-like states. According to quantum mechanics, evolution of time would not change this initial state because the potential is time independent. However, classically we expect the electron to collide with the sphere. So, it seems that the quantum and classics predict different behaviours!
Back
Top