Electron-Proton Collisions: Understanding the Quantum Dynamics

[cam875]

I think this is where I need to be thinking at a quantum level and not a classical level but i keep thinking if an electron travels at the right heading at an atom it would just crash into the nucleus and since opposites attract they would bond and have a nucleus with an electron sticking to it. I mean if the electron was traveling at the correct speed and heading it would enter a nice orbit and all would be good, but than again that's thinking about bohrs model and since that's not correct anymore i think i could be disproved quite easily. So basically change my thinking here lol, thanks in advance.

 

[malawi_glenn]

The electron approaching the nucleus in quantum physics, is decribed by a plane wave (or other rather a gaussian wave package).

The thing you must get used of in quantum physics is that particles are not small cannon balls / biliard balls.

A particle in quantum physics is an entity that has wave properties and properties of a tiny cannon ball.

You should perhaps study scattering theory, there are many good resources for that.

 

[edguy99]

I think this is where I need to be thinking at a quantum level and not a classical level but i keep thinking if an electron travels at the right heading at an atom it would just crash into the nucleus and since opposites attract they would bond and have a nucleus with an electron sticking to it. I mean if the electron was traveling at the correct speed and heading it would enter a nice orbit and all would be good, but than again that's thinking about bohrs model and since that's not correct anymore i think i could be disproved quite easily. So basically change my thinking here lol, thanks in advance.

Hopefully someone corrects me if wrong, but the crash does not happen as both the electon and proton are assumed to be point charges with no definable size that would allow the crash. They seem to pass right though each other.

 

[malawi_glenn]

but the proton is not point particle, and you are again thinking "classical", particles as tiny balls.

 

[cam875]

ok so if the electron is a wave than what exactly happens when it approaches the waves of the quarks, does it scatter or something, is that why you told me to study scattering theory of waves?

 

[malawi_glenn]

yes, scatter. Some elastic scattering, and some inelastic scattering

 

[cam875]

is it heavy mathematical? I am still a high school student so...

 

[edguy99]

but the proton is not point particle, and you are again thinking "classical", particles as tiny balls.

Thank you for the correction.

In post #2 you say "The thing you must get used of in quantum physics is that particles are not small cannon balls / biliard balls.

A particle in quantum physics is an entity that has wave properties and properties of a tiny cannon ball."

I am not sure I understand your distinction between the "small cannon balls" vs "tiny cannon ball"?

 

[malawi_glenn]

is it heavy mathematical? I am still a high school student so...

well it is upper undergraduate/early graduate - level, so maybe wait 3-4 years ;-)

 

[malawi_glenn]

Thank you for the correction.

In post #2 you say "The thing you must get used of in quantum physics is that particles are not small cannon balls / biliard balls.

A particle in quantum physics is an entity that has wave properties and properties of a tiny cannon ball."

I am not sure I understand your distinction between the "small cannon balls" vs "tiny cannon ball"?

i) grammar: in first quotation I was talkning about particleS, hence the sentence must end with ballS

ii) small and tiny are synomous words, they mean the same thing

 

[cam875]

is it ok and safe to make a jump and think about all fundamental particles purely as waves or does it not work unless their both particles and waves, because waves seems the way to go since quantum mechanics is basically wave mechanics.

 

[edguy99]

"The thing you must get used of in quantum physics is that particles are not small cannon balls / biliard balls.

A particle in quantum physics is an entity that has wave properties and properties of a tiny cannon ball."

I was not confused about the "s", but was hoping to get you to elaborate on the principle of not a small cannon ball(s) in the first sentence vs having the properties of a tiny cannon ball(s) in the second sentence. The 2 sentences seem to be contradictory, but I thought you were perhaps trying to make a point by wording it that way.

 

[malawi_glenn]

is it ok and safe to make a jump and think about all fundamental particles purely as waves or does it not work unless their both particles and waves, because waves seems the way to go since quantum mechanics is basically wave mechanics.

In non relativistic quantum mechanics one descibe particles by probability waves (wavefunction) but also with charge-(or whater ever quantity) distributions (i.e to determine their "shape")

In relativistic quantum mechanics (Relativistic quantum field theory) situation is different.

 

[malawi_glenn]

"The thing you must get used of in quantum physics is that particles are not small cannon balls / biliard balls.

A particle in quantum physics is an entity that has wave properties and properties of a tiny cannon ball."

I was not confused about the "s", but was hoping to get you to elaborate on the principle of not a small cannon ball(s) in the first sentence vs having the properties of a tiny cannon ball(s) in the second sentence. The 2 sentences seem to be contradictory, but I thought you were perhaps trying to make a point by wording it that way.

The first sentence says that the ARE not small balls. The second says that they have properties AS IF they would be small balls, but since they also have many other properties (which is also contradictorous to how a ball behave in Newtonian dynamics), they are simply not balls.

 

[ZapperZ]

Just in case people didn't know this, HERA at DESY is an electron-proton collider. So electron colliding into a "nucleus" (a proton is, after all, the hydrogen nucleus) is a well-known and well-studied process.

Zz.