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I think I broke it: Question: Why did civilization form when it did? Answer: The Earth formed about 4.5 billion years ago. The first life forms appeared about

I think I broke it: Question: Why did civilization form when it did? Answer: The Earth formed about 4.5 billion years ago. The first life forms appeared about 3.5 billion years ago. The first single-celled organisms were probably bacteria. The first multi-celled organisms were probably protists. The first animals were probably sponges. The first plants were probably green algae. The first land plants were probably mosses. The first animals to live on land were probably insects. The first vertebrates were probably fish. The first amphibians were probably amphibians. The first reptiles were probably reptiles. The first mammals were probably mammals. The first birds were probably birds. The first dinosaurs were probably dinosaurs. The first mammals to live on land were probably mammals. The first reptiles to live on land were probably reptiles. The first amphibians to live on land were probably amphibians. The first fish to live on land were probably fish. The first insects to live on land were probably insects. The first plants to live on land were probably plants. The first land animals were probably..

otabdeveloper4 4y ago
Speed of sound in vacuum The speed of sound in vacuum is the speed of sound in a perfect vacuum. In a perfect vacuum, there are no molecules to support the propagation of sound, so sound cannot propagate through it. This speed is usually referred to as "the speed of sound" and is usually denoted by c, which is the standard notation for the speed of light. In fact, the speed of light is very close to the speed of sound in a perfect vacuum. The speed of sound in a perfect vacuum is the theoretical upper limit for the speed of sound in any substance.
- JPLeRouzic 4y ago
  > the speed of light is very close to the speed of sound in a perfect vacuum I am not knowledgeable in physics but this looked wrong to me until I reflected that in a near vacuum, the elasticity is very high and density nearer to zero. So per the equation of speed of sound, (square of ( elasticity / density ) ) is extremely high, so near the speed of light. Not so bad.
  - orbifold 4y ago
    The reply to the prompt is almost complete non-sense. In particular the statements about the speed of sound in vacuum. However in some instances (synthetic quantum systems) you can treat the speed of sound in an ultra-cold gas as the „light-speed“ in a curved space-time. This was recently experimentally demonstrated. I think in the future humans will need to invent secret languages, not digitized or shared with computers in order to be able to filter wrong but convincing information.

otabdeveloper4 4y ago

Speed of sound in vacuum The speed of sound in vacuum is the speed of sound in a perfect vacuum. In a perfect vacuum, there are no molecules to support the propagation of sound, so sound cannot propagate through it. This speed is usually referred to as "the speed of sound" and is usually denoted by c, which is the standard notation for the speed of light. In fact, the speed of light is very close to the speed of sound in a perfect vacuum. The speed of sound in a perfect vacuum is the theoretical upper limit for the speed of sound in any substance.

JPLeRouzic 4y ago
> the speed of light is very close to the speed of sound in a perfect vacuum I am not knowledgeable in physics but this looked wrong to me until I reflected that in a near vacuum, the elasticity is very high and density nearer to zero. So per the equation of speed of sound, (square of ( elasticity / density ) ) is extremely high, so near the speed of light. Not so bad.
- orbifold 4y ago
  The reply to the prompt is almost complete non-sense. In particular the statements about the speed of sound in vacuum. However in some instances (synthetic quantum systems) you can treat the speed of sound in an ultra-cold gas as the „light-speed“ in a curved space-time. This was recently experimentally demonstrated. I think in the future humans will need to invent secret languages, not digitized or shared with computers in order to be able to filter wrong but convincing information.