Newton, Time Arrow & Egg Unbreaking: Is it Possible?

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Discussion Overview

The discussion revolves around the possibility of reversing the breaking of an egg, exploring the implications of Newton's laws and the second law of thermodynamics. Participants examine the energy transformations involved in the process and the statistical nature of such reversals, touching on concepts of time's arrow and probability.

Discussion Character

  • Exploratory
  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • Some participants propose that Newton's laws do not explicitly forbid the unbreaking of eggs, suggesting that the second law of thermodynamics is the primary reason such events do not occur.
  • Others argue that while energy is conserved according to the first law of thermodynamics, the second law prevents the conversion of dispersed energy back into the organized energy needed to lift the egg back to its original position.
  • A participant compares the scenario to a superball, stating that it will never bounce back to the same height as it was dropped, implying a similar irreversibility in the egg's case.
  • One participant elaborates that if all surrounding molecules were to move in the same direction, theoretically, the egg could return to its original position, but this is statistically improbable.
  • Another viewpoint suggests that the arrow of time is determined by probability rather than physical laws, indicating a philosophical angle to the discussion.

Areas of Agreement / Disagreement

Participants generally agree that the second law of thermodynamics plays a crucial role in the impossibility of unbreaking an egg, but there are competing views on the implications of Newton's laws and the nature of time's arrow. The discussion remains unresolved regarding the philosophical interpretations of these concepts.

Contextual Notes

Limitations include the dependence on interpretations of thermodynamic laws and the statistical nature of molecular behavior, which are not fully resolved in the discussion.

Ratzinger
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Once in while I read that Newton laws do not forbid the unbreaking of eggs. The only reason that we don’t see it and similar events is the second law of thermodynamics.

Is that correct? If an egg falls off the table, isn’t then the reverse process also forbidden by Newton, then how should the egg shell and yolk go up against gravity and get to the table? Where should the energy come from?
 
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Ratzinger said:
Where should the energy come from?
Let's look at what happens when the egg falls. Gravitational potential energy is converted into kinetic energy. As the egg hits the ground, that kinetic energy goes into changing the internal energy of the floor and the egg (deforming aka breaking the egg) and into things like heat and sound.

The point is that energy is conserved according to the first law of thermodynamics. It would not be a violation of conservation of energy if all of that heat and internal energy went back into the egg to put it back together and give it enough kinetic energy to jump back up to the table.

However, like you said, according to the second law of thermodynamics that will never happen.
 
I also look at it this way: There is no "superball" that will ever bounce back to the same height as dropped(not throwing).
 
Ratzinger said:
Once in while I read that Newton laws do not forbid the unbreaking of eggs. The only reason that we don’t see it and similar events is the second law of thermodynamics.

Is that correct? If an egg falls off the table, isn’t then the reverse process also forbidden by Newton, then how should the egg shell and yolk go up against gravity and get to the table? Where should the energy come from?
The gravitational energy was converted into kinetic energy of the egg. When the egg crashed, that energy dispersed into the surroundings as heat, ultimately. It is still there. However, the second law prevents it from being used to do work to lift the egg back up to where it was.

If all the molecules in the surroundings under the egg suddenly moved in the same direction (up), the egg could move back to where it was. But it is statistically so improbable that it will never happen in 100 gazillion lifetimes of this universe.

So, the arrow of time is determined not by any law of physics but by the law of probability.

AM
 

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