Geophysical and mineral physics studies confirm that temperatures within Earth's deep interior, including the core-mantle boundary and inner core, reach several thousand degrees Celsius.
The retrieved papers examine core and mantle temperatures under high pressure using experimental and computational methods. They consistently report melting and eutectic temperatures at the core-mantle and inner-core boundaries exceeding 3,000 to 4,300 Kelvin (thousands of degrees Celsius), directly supporting the claim.