By getting superconducting theory right (or making enough progress from theory and better experiment), we could guide material design of room temperature superconductors, higher current density material, better electronics, better power grid, possible magnetically ground launched space craft.

Room-temperature superconductors would be an important milestone on the path to complete mastery (within the actual limits of physics) of information, light, energy, magnetism, and matter. (ILEMM control)

What seems doable with far greater mastery of ILEMM:
Molecular nanotechnology

Large scale Quantum computers (millions of qubits)

Large scale space structures for solar energy collection and propulsion

Magnetic formation flying

Magnetically inflated cable

Light sails and beamed propulsion

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Advanced metamaterials

Antimatter storage and harvesting work could eventually lead to the large scale creation of artificial mini-magnetospheres to allow antimatter to be created and collected.

Brian Wang

Brian Wang is a Futurist Thought Leader and a popular Science blogger with 1 million readers per month. His blog Nextbigfuture.com is ranked #1 Science News Blog. It covers many disruptive technology and trends including Space, Robotics, Artificial Intelligence, Medicine, Anti-aging Biotechnology, and Nanotechnology.

Known for identifying cutting edge technologies, he is currently a Co-Founder of a startup and fundraiser for high potential early-stage companies. He is the Head of Research for Allocations for deep technology investments and an Angel Investor at Space Angels.

A frequent speaker at corporations, he has been a TEDx speaker, a Singularity University speaker and guest at numerous interviews for radio and podcasts. He is open to public speaking and advising engagements.