Why Do Spin 1/2 Particles Behave Like a Twisted Ribbon?

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Discussion Overview

The discussion revolves around the behavior of spin 1/2 particles, using a metaphor involving a stein and a ribbon to illustrate the concept of spin in quantum mechanics. Participants explore the implications of this analogy and the nature of spin itself, questioning its interpretation and relevance.

Discussion Character

  • Exploratory
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • One participant suggests that the analogy of the stein and ribbon illustrates how spin 1/2 particles return to their original state after two full turns, unlike other particles.
  • Another participant humorously proposes that the trick is actually performed by another person, implying that the concept of spin is misleading and questioning the validity of physics as a whole.
  • A different viewpoint presents a more abstract interpretation, suggesting that the nature of spin 1/2 is tied to the particle's surface rather than its geometric center, hinting at deeper implications for understanding gravity.
  • One participant diverts from the scientific discussion to humorously suggest a personal interaction, offering a telephone number instead of addressing the scientific question.

Areas of Agreement / Disagreement

Participants do not reach a consensus, as multiple competing views and interpretations of the spin concept are presented, with some focusing on the metaphor and others questioning the underlying physics.

Contextual Notes

The discussion includes speculative interpretations of spin and its implications, with varying degrees of seriousness and humor, reflecting a lack of resolution on the nature of spin 1/2 particles.

Edward Green
The first two vanish into the back room to play a game of darts,
leaving the third to chat up the barmaid. After emptying a stein, he
pulls a bit of ribbon from his pocket and entertains her with a trick
whereby he ties the ribbon to the handle, twists the stein around two
full turns, and then magically untwists the ribbon without moving the
stein. He tells her how particles he studies have a property called
"spin", and that particles whose spin is 1/2 actually behave like the
stein with the ribbon tied to it: coming back where they started only
after two, but not one, full turns. Feynman then leans closer, and
conspiratorially whispers to her why (in language a barmaid can
understand), just spin 1/2 particles act this way, and not other
particles.

What story does the Feynman tell the barmaid?
 
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Edward Green wrote:

> The first two vanish into the back room to play a game of darts,
> leaving the third to chat up the barmaid. After emptying a stein, he
> pulls a bit of ribbon from his pocket and entertains her with a trick
> whereby he ties the ribbon to the handle, twists the stein around two
> full turns, and then magically untwists the ribbon without moving the
> stein. He tells her how particles he studies have a property called
> "spin", and that particles whose spin is 1/2 actually behave like the
> stein with the ribbon tied to it: coming back where they started only
> after two, but not one, full turns. Feynman then leans closer, and
> conspiratorially whispers to her why (in language a barmaid can
> understand), just spin 1/2 particles act this way, and not other
> particles.
>
> What story does the Feynman tell the barmaid?[/color]

Ah ha he tells her : The trick is one of the other Feynmans sneaks out of
the back room and untwist the ribbon when she isn't looking. The quantum
particles are not spinning so calling this property spin is also a trick."

This makes the barmaid think "All physics is crap. But hey those guys make
plenty of money. Right?"

--
You do realize...
 
Edward Green wrote:
> The first two vanish into the back room to play a game of darts,
> leaving the third to chat up the barmaid. After emptying a stein, he
> pulls a bit of ribbon from his pocket and entertains her with a trick
> whereby he ties the ribbon to the handle, twists the stein around two
> full turns, and then magically untwists the ribbon without moving the
> stein. He tells her how particles he studies have a property called
> "spin", and that particles whose spin is 1/2 actually behave like the
> stein with the ribbon tied to it: coming back where they started only
> after two, but not one, full turns. Feynman then leans closer, and
> conspiratorially whispers to her why (in language a barmaid can
> understand), just spin 1/2 particles act this way, and not other
> particles.
>
> What story does the Feynman tell the barmaid?[/color]

A spin as described where the Feynman theorest is the only allowed
answered is a quite simple story.

"A spin to the stein takes the steinist out of all."

A story where the particle never quite entertains the state in
question. A transverse.

Why spin 1/2 exists is the stein. A large effect making the surface the
particle as opposed to the geometric center. Causing all dilemma to
vanish. Gravity all.
 
Edward Green said:
The first two vanish into the back room to play a game of darts,
leaving the third to chat up the barmaid. After emptying a stein, he
pulls a bit of ribbon from his pocket and entertains her with a trick
whereby he ties the ribbon to the handle, twists the stein around two
full turns, and then magically untwists the ribbon without moving the
stein. He tells her how particles he studies have a property called
"spin", and that particles whose spin is 1/2 actually behave like the
stein with the ribbon tied to it: coming back where they started only
after two, but not one, full turns. Feynman then leans closer, and
conspiratorially whispers to her why (in language a barmaid can
understand), just spin 1/2 particles act this way, and not other
particles.

What story does the Feynman tell the barmaid?

He gives her his telephone number & map to his home... "See you after work dear lass." :-p
 

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