How Would Our World Change if hbar Were Larger?

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    Conceptual Quantum
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Discussion Overview

The discussion explores the hypothetical implications of a larger reduced Planck's constant (hbar) on our macroscopic world, focusing on the potential changes in behavior of objects and the nature of physical laws. Participants consider the effects on quantum behavior, uncertainty principles, and the conceptual transition from classical to quantum mechanics.

Discussion Character

  • Exploratory
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • Some participants question how much larger hbar would need to be for macroscopic objects to exhibit quantum behavior.
  • One participant references Heisenberg's uncertainty principle to speculate on the consequences of increased uncertainty in position and momentum.
  • Another participant suggests that hbar's perceived smallness is dependent on the units used, proposing that if hbar were of order one in mks units, the world would resemble the atomic realm.
  • A participant reflects on the implications of higher momentum uncertainty, questioning whether it would affect the ability to know both position and momentum simultaneously.

Areas of Agreement / Disagreement

Participants express various speculative ideas about the implications of a larger hbar, but there is no consensus on the specific outcomes or the extent of changes that would occur in the macroscopic world.

Contextual Notes

Participants acknowledge the dependence of their arguments on the definitions and interpretations of quantum mechanics and uncertainty principles, but these aspects remain unresolved.

ayalam
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1. Planch's constant[h bar] is really small, so small that in our macroscopic world we generally can't notice it. what if [h bar] were larger, what would our world be like if it were larger? How much larger would it have to be to so that macroscopic objects displayed "quantum behavior'.

2. how will our world be different if [h bar] were larger?
 
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Take Heisenberg's uncertainty principle:

uncertaintyinposition*uncertaintyinmomentum>=h/4pi.

And try to imagine what could happen.
 
hbar is only seems small because it is a small number if you use mks units.
In the same way the Earth is tiny if you use light years.
If you use atomic units, hbar is of order one.
Then you get the atomic world of atomic physics.
If hbar were of order one in mks units, we would be living in the atomic world.
There are books by George Gamow, "Mr. Thompkins in Wonderland",
published by Dover, that describe this world.
 
So if hbar were higher then momentums uncertainty will be higher. I understand that, i understand that the world would be different. For example I could walk to the store you can either know where I'm at (positon)or know my momentum never both. would that be the case? It makes sense to me that a 5000 hp car although fast to us is slow compared to maybe a cosmic ray.
 

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