Factual error: The depiction of lasers is completely off in the movie. While surgical laser is indeed a real thing, such a highly concentrated beam with enormous cutting power seen in the film would take industrial size instruments and an extremely high power supply. Also, a laser beam simply doesn't look that way. Those scenes are way off into science fiction for an otherwise raw and realistic-looking thriller.
Factual error: Just after feeling the explosion from the south tower, Eddie's watch shows 17:37 whilst others and himself are stuck in the North tower elevator. The planes hit the towers in the morning. (00:35:00)
Factual error: One of the deaths involves a burning candle, a car and a leaking fuel tank, resulting in an explosion. This wouldn't happen. Multiple independent test evidence that petrol/gasoline can't be ignited this way, a flame isn't hot enough. Only the fumes can be ignited, which isn't what happens here, and the tank wouldn't explode anyway.
Factual error: No matter how sophisticated the STEM chip is, it would not enable Grey (Logan Marshall-Green) to go from a completely horizontal position to a completely vertical position in one fluid motion, without bending his knees, and he does this several times in the film.
Factual error: In the movie the professor's assistant says thst the professor was in OSS in the great war (WWI). OSS was first formed in 1941 by President Roosevelt.
Factual error: The opening shot is of a somewhat long and quite high bridge with an equally high waterfall behind it. After a couple views of the surroundings, Henry and Peter are standing in the middle (portion) of a stone barricade/wall (extension of the bridge?) with a huge lake behind it, waiting for the school bus. There's absolutely no legitimate or rational reason for such a location to be a school bus stop! School bus stops always have safety in mind, and this bus stop is anything but safe. (00:02:32)
Factual error: The police Lieutenant Hightower is wearing the rank of Captain.
Factual error: The accident takes place the night of July 18, 1969, and they show there being a full moon. That night the moon was actually waxing crescent with only 14% visible, and set at 10:27pm while the accident happened about 12:45am, so there was no moon in the sky anyway.