So I’m only 3 episodes into the Netflix show but as a huge fan of the books, creating new physics wouldn’t work since they have broken our existing physics models with sophon tech :-) you could set up a base on the moon or mars to discover new physics, but then you’re losing maybe 50-100 years of resources leaving you less than 300 years to come with advanced enough tech to colonize multiple systems and spread humanity’s reach to avoid extinction l, create advanced enough weaponry to mount an offensive, or create advanced enough wormhole or some other space time manipulation tech to move your local sector into a higher or lower dimension or somehow mask all electromagnetic emissions from detection.