The double-slit experiment

Jon

Administrator
Staff member
#1
For those who know about this famous experiment, I just wanted to say what a mind boggling outcome! It change the course of physics forever! The discovery that electrons fired from some kind of emitter through two slits would end up with a wave pattern, rather than two vertical lines was eye opening. How is it that electrons can behave as both particles and waves?

https://plus.maths.org/content/physics-minute-double-slit-experiment-0
 

The_Doc_Man

Founding Member
#2
Because we don't truly know what particles or waves are (in this context), the problem is human-imposed. Nature is doing just fine. We're the ones still playing in the mud.
 

Insane_AI

Founding Member
#3
I've seen the experiment multiple times. They never seem to account for variances in the trajectory or address the concept that the particles may be interacting with the shield before the background and thus the variance could simply be ricochet.

It's like watching a magic show; you know there's a reasonable explanation for it all, but you aren't getting it from the presenter.
 

The_Doc_Man

Founding Member
#4
the variance could simply be ricochet.
This viewpoint is emphasizing the particle nature of the electron beam when you must remember that they are moving at high speed and thus have a non-trivial DeBroglie wavelength as well. As such, they are moving bits of whatever a string becomes when it combines with other strings. Whatever it is, OUR IMPERFECT VIEWPOINT is the reason for confusion. We don't fully understand it so we fuss over it. But Mother Nature is not trying to fool us. She is just waiting for us to gain enlightenment.
 

Uncle Gizmo

Founding Member
#6
I get regular emails about cutting Edge science and I recall receiving one the other day about an unknown organizing principle. As a layman explaining it in layman's terms, I'm in danger of getting it wrong! However it appears that superconducting metals exhibit a strange property which scientists are just beginning to grasp the nature of. It appears that at a particular temperature "all" of the electrons become quantum entangled. I'm not 100% sure if it has been verified yet, however it's an interesting read. If they can prove it's an actual effect then it will hopefully give insights into the whole area of quantum physics.

This was the simplest to read article I could find with a 5-minute search...

Extract:-
a growing belief among physicists that an unknown organizing principle governs the collective behavior of particles and determines how they spread energy and information

https://www.theatlantic.com/science...-superconductors-electron-speed-limit/576484/
 

The_Doc_Man

Founding Member
#7
Excellent choice of article, Uncle G. I noted in the body of that article that two of the researchers earned a Nobel Prize for their work. They are not the first to have earned one, though, in the field of superconductivity. John Bardeen, Leon Neil Cooper and John Robert Schrieffer won the Nobel Prize in 1972 for their work on the subject. They treated superconductivity as a "2nd order phase transition" and their math solidified the concept.

To simplify the idea of "phase transitions," various properties of matter change with changes of temperature. For example, ice melts or water freezes; water boils or steam condenses. These are changes to/from solid, liquid, or gas. These are called "1st order phase transitions." Simple enough, right? An example of a 2nd order transition is when you heat up a permanent magnet above the Curie temperature, the magnetism is lost because the atomic-level "magnetic domains" of the magnetic material become scrambled. The magnet doesn't melt (so not 1st order) but DOES lose its magnetism. We now understand that this means the spin orientation of the valence electrons of the magnet, which had been aligned, become randomized. Bardeen and his colleagues showed that like magnetic disorientation through heat, the development of superconductivity through cold was a 2nd order transition. Chalk up yet another big win for Bell Labs.

Their idea of electrons "joining up with one another" was the early statement of entanglement before that word had come into common usage in terms of quantum physics. I had to do a presentation on this topic as part of my doctoral program. Their work put a stronger theoretical foundation under something that was just being discovered at the time - measuring devices that used superconductivity to improve sensitivity by literal orders of magnitude. One example I recall was a bolometer (remote sensor of infra-red heat emissions) that became capable of measuring things to the level of 100 nanowatts. (In 1972, that was BIG stuff for astronomers trying to measure information about stellar gas emissions.) This was important to chemists because more sensitive detection devices permit more precise measurements.
 
Top