From StarTalk.

Neil answers if a “constant-acceleration” space drive could give artificial gravity. Yes—if you thrust the whole trip you feel acceleration like gravity (Einstein’s equivalence principle). The fast Mars plan is: accelerate to halfway, flip the ship, decelerate (“flip & burn”), but it demands huge propellant or refuel depots. Most current trips are coasts: push off Earth, drift, then fall into Mars—so astronauts are weightless because they’re in free-fall, not because “space has no gravity.” They also riff on movies that get this wrong and end with a head-scratcher on photons, time dilation, and redshift.

From ‘Answering Fan Queries About Strange Matter, the Insides of Black Holes & More’: https://youtu.be/i7vGoILa5qk?si=X8WyLHbwZHAdozHm

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