In the film depicting the testing of Oppenheimer's bomb, there's a notable scene where the sound appears to come in late, creating an unusual effect.
This choice seems intentional, but I'm curious about its rationale. Was this a deliberate artistic decision for dramatic effect, or does it have a historical or technical basis? I'm interested in understanding the director's intention or any technical aspects that led to this unique auditory experience in the scene.
Light travels faster than sound, that's the same reason we see lightning before we hear thunder. The same tried to be portrayed in the movie.
Screenrant tried to cover it too:
The delayed sound in Oppenheimer's Trinity test scene scientifically portrays how light travels faster than sound. According to the Trinity test site map, the first observation deck, from where Oppenheimer and his team observed the nuclear detonation, was located about 6 miles away from the detonation site. Since time = distance/speed, where the distance is 9656.06m (6 miles), and speed is 343 m/s (speed of sound), it would take close to 28 seconds for the sound of the nuclear explosion to reach the observation deck from where Oppenheimer and his team were observing the test.
WGTC covered it well with the words of Richard Feynman himself:
It’s a great moment in the film, but was it the case in real life? The answer is yes. For around 90 seconds, the New Mexico desert was deathly quiet, despite the blinding flash and plumes of fiery smoke seen rising into the sky. To Oppenheimer and his team of observers, it must have seemed a lifetime.
Physicist Richard Feynman explained what happened next. “Finally, after about a minute and a half, there’s suddenly a tremendous noise – BANG, and then a rumble, like thunder.” Feynman waited unmoving with his fellow horrified onlookers. After a few moments, a man standing next to him asked, “What’s that?” Feynman replied, “…That was the bomb.”
