Is Our Understanding of Gravity and Entropy Incomplete?

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In summary, the conversation discusses the concept of the universe's origin and its current state of disorder. The speaker concludes that the number of possible states of existence has increased over time and that the understanding of gravity and entropy is incomplete. They express discomfort with relying on untestable explanations such as strings and extra dimensions. Additionally, the concept of causality is questioned and the idea of a universe without predictable consequences is deemed impossible. Finally, the idea of galaxies as disorder is challenged and the progression from a disordered gas to a more orderly universe is mentioned.
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Chronos
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It is fairly evident the universe originated in a more highly ordered state than we presently observe. It is also fairly evident it has become increasingly disordered over time [e.g., expansion and those inexplicable clumps of matter called galaxies, stars, etc.]. I am therefore forced to conclude the number of possible states of existence have increased over time. The concept of action and reaction [blame Newton and Laplace] seem to insist current explanations for gravity and entropy are incomplete. I am very uncomfortable having to rely upon untestable explanations. Strings and extra dimensions are not very satisfying. They appear to require a higher order of 'law' that is inherently impossible to validate by observation. The long and the short of it... a universe without predictable consequences [causality] cannot exist in my local reference frame.

Thoughts?
 
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IIRC, according to BBT, there was much more homogeneity to the universe once upon a time. no large atoms, only H and maybe some He. just clouds of gas waiting for gravity to do its magic.

by "order", do you mean neat rows of similar things? do you mean repetition? do you mean "information" ?

what do you mean by "states of existence" ?
do you mean thermodynamic microstates? since that's what entropy deals with?

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how are galaxies considered "disorder"? It seems like the universe went from conceptually disordered (a bunch of spread out, whizzing-around, light atoms in a gas) to what we would conceive of as "order". Solids, crystals, planets, regular motion about centers of gravity, etc.

:rolleyes:
 
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FAQ: Is Our Understanding of Gravity and Entropy Incomplete?

1. What is entropy?

Entropy is a measure of the disorder or randomness in a system. It is a concept used in thermodynamics and statistical mechanics to describe the distribution of energy and the degree of disorder in a system.

2. How is entropy related to classicality?

In classical physics, entropy is closely related to the concept of disorder. As a system becomes more disordered, its entropy increases. In terms of classicality, entropy can be seen as a measure of the system's departure from a classical state of equilibrium.

3. Can entropy be reversed?

In classical physics, entropy is a measure of the probability of a system to evolve into a more disordered state. This means that it is highly unlikely for entropy to decrease or for a system to become more ordered. However, in certain cases, such as in a closed system, entropy can decrease temporarily but will eventually increase again.

4. How does entropy relate to the laws of thermodynamics?

The second law of thermodynamics states that the total entropy of a closed system will always increase or remain constant. This means that energy will naturally flow from highly organized states to more disordered states, leading to an increase in overall entropy. In this way, entropy is closely related to the laws of thermodynamics.

5. What is the difference between classical and quantum entropy?

Classical entropy is based on the concept of disorder and can be calculated using statistical mechanics. In contrast, quantum entropy is a measure of the uncertainty or information contained in a quantum system. It is based on the principles of quantum mechanics and is often described as a measure of the "quantumness" of a system.

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