Is it possible to construct a thermally isolated system?

[iScience]

If I'm just trying to design a system to minimize heat loss, would the following suffice?
The system or object would be magnetically levitated inside a vacuum chamber. The interior lining of the vacuum chamber would also be covered in a sheet of radiation reflecting material.

 

[anorlunda]

Those measures are good, but not perfect. We can't answer your question unless you provide some numerical requirements. How good does it need to be? How much money do you have?