One of the orders President Donald Trump is signing Monday calls for developing by 2028 the “first-ever quantum computer powerful enough for scientific research,” said Michael Kratsios, director of the White House’s Office of Science and Technology Policy. The second order seeks to bolster the nation’s cybersecurity, anticipating a time when such powerful computers will be able to break the best encryption. Trump’s directives mark the latest attempts to tap into the strange behavior of subatomic particles to build machines that could perform calculations at far higher speeds than conventional supercomputers.