Energy and the end of the universe.

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Discussion Overview

The discussion centers on the concept of energy in relation to the "heat death" of the universe, exploring the implications of energy conservation, entropy, and the potential for future states of the universe. It touches on theoretical interpretations and the nature of energy, particularly in the context of thermodynamics and cosmology.

Discussion Character

  • Exploratory
  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • Some participants question the notion of "heat death," arguing that while energy cannot be created or destroyed, its ability to effect change diminishes as it becomes uniformly distributed as heat.
  • There is a proposal that entropy represents the conversion of free energy into heat energy, and that the statistical nature of states may allow for fluctuations that challenge the idea of a definitive heat death.
  • One participant suggests that the concept of heat death may be outdated, raising questions about the potential for new structures or elements to emerge in a future universe.
  • Another participant clarifies that "not free" energy refers to energy confined to motion without temperature differentials, leading to a state of equilibrium dominated by photons.
  • There is a mention of proton decay as a theoretical consideration, with a participant noting that it has not been experimentally detected.

Areas of Agreement / Disagreement

Participants express differing views on the implications of energy conservation and the validity of the heat death concept, indicating that multiple competing perspectives remain without consensus.

Contextual Notes

Participants highlight the limitations of current understanding regarding proton decay and the assumptions underlying the heat death theory, indicating that these aspects are still open for discussion.

mee
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If energy can neither be created or destroyed, why is there supposedly a "heat death" or any sort of death to the universe.
 
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Energy can be free or not. If it's free it can do things, if it's not the only thing it can do is make heat. If the heat is the same temperature everywhere, nothing physical can happen on the larger scale. Entropy is the conversion of free energy into heat energy. The energy is not destroyed but its ability to effect change is no more.

This is now seen as a statistical effect, of the more probable states succeeding the less probable ones. And there could always be a quantum fluctuation, so the heat death is not the ultimate last thing the nineteenth century physicists envisioned.
 
Last edited:
heat and energy

selfAdjoint said:
Energy can be free or not. If it's free it can do things, if it's not the only thing it can do is make heat. If the heat is the same temperature everywhere, nothing physical can happen on the larger scale. Entropy is the conversion of free energy into heat energy. The energy is not destroyed but its ability to effect change is no more.

This is now seen as a statistical effect, of the more probable states succeeding the less probable ones. And there could always be a quantum fluctuation, so the heat death is not the ultimate last thing the nineteenth century physicists envisioned.

I assume by non free energy you mean matter and by heat you mean fusion or like in the Earth's core perhaps. Does heat not mean like in the cores of stars? Would this heat not effect change like fusion? Will there perhaps be a universe which is full of higher elements with new types of structures we currently don't understand coming into being? Are you basically telling me that "heat death" of the universe is an outdated concept?
 
No, by not free I mean energy confined to jiggling, with no temperature differential anywhere. Matter is unstable on the longest scale (protons eventually decay even in the standard model), so that eventually we are talking about a bath of photons at equilibrium.
 
Thank you.

selfAdjoint said:
No, by not free I mean energy confined to jiggling, with no temperature differential anywhere. Matter is unstable on the longest scale (protons eventually decay even in the standard model), so that eventually we are talking about a bath of photons at equilibrium.

But we have never actually detected a proton decay right?
 

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