Understanding Spin: Share Your Ideas!

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Discussion Overview

The discussion revolves around the concept of spin in quantum mechanics, exploring its nature, understanding, and implications. Participants share their thoughts on how to conceptualize spin, its mathematical representation, and its relation to other quantum principles.

Discussion Character

  • Exploratory
  • Conceptual clarification
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • Some participants express difficulty in forming a mental image of spin, questioning its nature and representation.
  • One participant suggests that spin is a conserved quantity, similar to energy and momentum, referring to it as "conservation of spin."
  • Another participant argues that spin, like many quantum concepts, is fundamentally ungraspable and should be learned mathematically rather than through visualization.
  • Some participants propose that visualization can be achieved by likening spin to the Earth's rotation, although this analogy may not fully capture its quantum nature.
  • There is a reference to Einstein's skepticism towards quantum theory, with a participant cautioning against using his quotes in discussions about quantum mechanics.
  • One participant mentions John Bell's inequalities and their implications for quantum entanglement, suggesting that the debate over the completeness of quantum theory remains unresolved.

Areas of Agreement / Disagreement

Participants do not reach a consensus on how to understand spin, with multiple competing views on its conceptualization and the validity of visualization versus mathematical learning. The discussion remains unresolved regarding the nature of spin and its implications in quantum mechanics.

Contextual Notes

Some limitations in understanding spin are noted, including the reliance on mathematical definitions and the challenges posed by human imagination in grasping abstract quantum concepts.

luxiaolei
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Hi, all.

Would anyone suggest your own idea about what actually spin it is? I can not form an image

in my head about spin...

Spin is vector, can be 1/2 can be 1, and if say it is 1/2, then Spin's Z component can be -1/2 or +1/2 ...??! and the magnitude of spin vector is:

|S| = sqrt(S(S+1)) ?! how to really really understand it?

Please leave your own idea, it will be great helps!

Thanks in advance!
 
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luxiaolei said:
Hi, all.

Would anyone suggest your own idea about what actually spin it is? I can not form an image

in my head about spin...

Spin is vector, can be 1/2 can be 1, and if say it is 1/2, then Spin's Z component can be -1/2 or +1/2 ...??! and the magnitude of spin vector is:

|S| = sqrt(S(S+1)) ?! how to really really understand it?

Please leave your own idea, it will be great helps!

Thanks in advance!

It may help to know that spin is a conserved quantity, just as energy or momentum are conserved quantities. Call this, "conservation of spin."
 
Spin is not understandable,just as many other quantum concepts,or as 4D space which cannot be imagined.
If you try hard to 'understand' it ,you will get yourself in trouble,since human imagination is limited to everyday stuff.Learn it mathematically.
 
netheril96 said:
Spin is not understandable,just as many other quantum concepts,or as 4D space which cannot be imagined.
If you try hard to 'understand' it ,you will get yourself in trouble,since human imagination is limited to everyday stuff.Learn it mathematically.

...But I can understand--in fact visualize--Heisenberg's Uncertainty Principle in action though!...
What was that maxim of Einstein's? Oh yeah. "Imagination is more important than knowledge."
 
Glen Bartusch said:
...But I can understand--in fact visualize--Heisenberg's Uncertainty Principle in action though!...
What was that maxim of Einstein's? Oh yeah. "Imagination is more important than knowledge."

Visualization is easy.Just regard spin as spin, like the Earth spinning around.


Einstein is a great scientist,but he is also famous for his dislike of quantum theory.You shouldn't cite his words when discussing quantum theory.
Otherwise I will cite " God does not play dice with the universe!"
 
netheril96 said:
Visualization is easy.Just regard spin as spin, like the Earth spinning around.


Einstein is a great scientist,but he is also famous for his dislike of quantum theory.You shouldn't cite his words when discussing quantum theory.
Otherwise I will cite " God does not play dice with the universe!"

Lulz, that last sentence of yours it's like... touche!
Anyways. Remember John Bell's inequalities [and their consequent violations] came most unexpectantly, so EPR was always considered more or less valid, up until Aspect conducted his great experiment (the Alain Aspect experiment) that verified entanglement and cast serious doubt on the concept of the hidden variable hypotheses.
I still believe Einstein has been right all along--that is to say that quantum theory is an incomplet one, just waiting for someone to come along with the Brilliant Idea which will explain the strange phonomena of entanglement...
 

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