Response to critiques on Observation of the Wigner-Huntington transition to metallic hydrogen

Understand

We reported the first observation of metallic hydrogen (MH) in the low temperature limit at a pressure of ~495 GPa in an article published in Science (1).

• This transition was first predicted by Wigner and Huntington (WE) over 80 years ago (2) at a pressure of ~25 GPa.
• In recent decades it became clear that the required pressure for metallization was far greater, in the 400-500 GPa range.
• Until now the observation of the WE transition in diamond anvil cells (DACs) has been prevented by one problem: the diamonds break before a sufficiently high pressure has been achieved.