The article is very light on details, but I believe what's being proposed is an evacuated tube with maglev propulsion, used to accelerate a rocket up to 5000mph (as stated in the article) while on the ground. The rocket is then released, and travels until some altitude is reached, at which point engine then starts and it continues to orbit. This results in a large fuel saving over a conventional rocket.
The g-forces involved would be very high, well beyond lethal to a human, so this would be for launching robust satellites, raw materials, or fuel cheaply into space. They would still be substantially lower than those of a space gun / intercontinental artillery.
https://en.wikipedia.org/wiki/Mass_driver
The g-forces involved would be very high, well beyond lethal to a human, so this would be for launching robust satellites, raw materials, or fuel cheaply into space. They would still be substantially lower than those of a space gun / intercontinental artillery.
https://en.wikipedia.org/wiki/Space_gun#Practical_attempts