Cinematic Brilliance.
Nolan is by far one of my favourite directors, between the dark knight, Dunkirk, tenet, the prestige, among others, he has proven himself more than capable in many relms, and biopics appear to be no exception.
From the start the movie jumps between time periods, and settings, funnily enough with the present day being black and white, and the "past" being in colour (I use quotation marks as it is the past during the narrative of the movie, while the entire movie is set in the past), I found this added to my enjoyment all the more.
The attention to detail is great, from the breif explanation of wave-particle duality to the way one with little knowledge of physics could understand what was happening.
Overall the movie is in and around 3 hours long, but not once did I check my watch or feel that it was "dragging" in any way, the movie felt very well paced.
Now for the effects, weather digital or practical (as many were), the striking visuals in this film are second to none, whether it be transporting you to a university of the early 1900s or a senate hearing decades after WW2 had ended, you know what time period it is and you know where it is.
The message at the end of (and throughout) the movie, is quite strong, that being "they won't fear it till they've used it, and by then, it will be too late", this harkens through with many technologies of war, however, none moreso than nuclear weapons, we fear them only because we have seen their destructive power.
People who are leaving negative reviews seem to care mostly about the fact that it didn't show the explosion in Japan and it didn't really focus on the death toll, however, as the movie makes clear, Oppenheimer didn't drop the bomb, he merely made it, and it does show him being remorseful at one point, continually he argues, wondering if there's another way, arguing against the creation of the hydrogen bomb (knowing it would only be more deviating).
In conclusion, the movie feels somewhat like a heist film with cutbacks/flash forwards (depending on your viewpoint) to the planning, the execution, the aftermath, etc. while all the while keeping you engaged and on the edge of your seat with a movie you know the outcome of (after all, you know going in the doors that the bomb is going to work). On top of this, I need to point out that the film is 100% worth seeing in IMAX if possible, the sound and picture are perfect, especially since it isn't upscaled for the screen, but rather filmed with IMAX cameras.
The movie does well with keeping it simple for those without any knowledge of science, every concept is explained in a linear manner, allowing people to follow the plot, and enjoy the movie, regardless of their educational background, while at the same time, having enough detail so as to not disappoint those with knowledge of nuclear physics.
Reading reviews is great, but "theory will only get you so far" so my advice is to go see the movie and make your own mind up.