My thoughts on the two:
1. No, here could be no such technological advances (super materials, interstellar travel, etc.) without calculations, ultra complex mathematical operations and working with immense numbers and variables at once. Unless there was such "matter" or solution that allowed sentient human beings to perform the calculations and run the diagrams, equations and such complex numbers, a computer or similar device would prove indispensable.
All modern machinery, engineering and technology development depends entirely on these calculations and mathematical operations, often running billions of them in incredibly tiny amounts of time (modern computers are in the order of peta- or teraflops, a flop being a floating comma operation) and such calculations cannot be replicated by living beings.
2. A society with such "bracelet artifact" available for its citizens would end up just like your question from last week "what if everybody could control matter, never die or need food, never be ill...?" and same answers apply.
There would be no society to speak of, and every human being would essentially become a God, breaking all social, economic, physiological and biological barriers.
now they'd only be limited by nature's laws such as the laws of Thermodynamics (energy balance, in vs out, entropy...)
but if you suggest that the energy limitations to build, create and manipulate matter were put off and could be avoided/tricked (by accessing quantum vacuum and altering the physical laws of macro-dimensions by playing with micro-dimensions) then there would essentially be a non-recognisable Universe with altered aspect and illogical working physics and chemistry, controlled by entities with limitless power and potency
at least that's my view on it.
As usual, interesting questions SEF!
