quantum tunnelling

[ayush garg]

what is quantm tunnelling and how it is used to measure the probability of electrons

[swansont]

Quantum tunneling is a phenomenon in which a particle can be found on the other side of a barrier which it could not classically overcome; the kinetic energy is smaller than the potential energy of the barrier in some region. The classical-analogy description is that they "tunnel through" the barrier; the QM solution shows that they can penetrate the barrier, and if it is thin enough, can appear on the other side.

 

Measure the probability of electrons doing what? Tunneling? You shoot electrons at a barrier and see what fraction make it through.

[granpa]

[steevey]

what is quantm tunnelling and how it is used to measure the probability of electrons

 

Particles have something called a wave function, which basically means it's a wave of existence but also a particle. A particle's wave function extends indefinitely as it can have higher and higher energy levels, but it's most probable to occur in the very small regions in and around an atom. What scientists suspect can happen, is that since an electron's probability can extend to great amounts, it's probability to appear in a location can exceed the boundaries of another object and appear there. Normally, this never ever happens with objects we can visually see, since it's the probability of one electron, which has to appear through at least 1,000,000 atoms, and the probability of electrons appearing at very far distances is about as close to nothing as you can keep getting. However, despite this, things still work in small distances, and some scientists think this quantum tunneling phenomena is the reason why fusion in the Sun occurs. They said they've done the math, and there just isn't enough heat an pressure to overcome the strong forces of particles to fuse them. So, what they think happens, is because protons also have a wave function, their probability can exceed each other's boundaries and find themselves in contact with ane another.