People forget that the Earth is about 99.9% either molten or quasi-solid core (iron, nickel, or Uranium and Thorium).
The heat of Accretion does not explain this phenomenon. You can calculate the Heat from Accretion using the Kelvin-Helmowitz equations, and Accretion should only have kept the Earth molten for a few hundred thousand to a few million years. IN order to keep the Earth molten for eight billion years, you need a significant portion of its original mass to be Radioactive materials, such as Uranium and Thorium, OR you'd need "Cold Fusion" reactions, a. k. a. "Low Energy Nuclear Reactions" to be happening inside the Earth's core.
Another possibility is the Earth's Magnetic Field actually heats up the Core as the Sun's Solar Wind interacts with the Magnetic Field, producing friction with the Magnetic Field, and delivering Heat from the Sun directly into the Core of the Earth, which also ultimately has the Earth's Heat coming from a Fusion (nuclear) reaction inside the Sun, rather than radio-isotopes inside the Earth itself.
Anyway, Accretion does not at all explain how the Earth could remain 99.9% molten or quasi-crystalline metal for 8 billion years.
The heat of Accretion does not explain this phenomenon. You can calculate the Heat from Accretion using the Kelvin-Helmowitz equations, and Accretion should only have kept the Earth molten for a few hundred thousand to a few million years. IN order to keep the Earth molten for eight billion years, you need a significant portion of its original mass to be Radioactive materials, such as Uranium and Thorium, OR you'd need "Cold Fusion" reactions, a. k. a. "Low Energy Nuclear Reactions" to be happening inside the Earth's core.
Another possibility is the Earth's Magnetic Field actually heats up the Core as the Sun's Solar Wind interacts with the Magnetic Field, producing friction with the Magnetic Field, and delivering Heat from the Sun directly into the Core of the Earth, which also ultimately has the Earth's Heat coming from a Fusion (nuclear) reaction inside the Sun, rather than radio-isotopes inside the Earth itself.
Anyway, Accretion does not at all explain how the Earth could remain 99.9% molten or quasi-crystalline metal for 8 billion years.
