Physics in Film

I had asked the library to get a copy of the original “Godzilla” (1954), but it appears it was easier for them to get a copy of the much more recent remake (1998). It’s not really that I thought the original (which I still have not seen myself) would be a higher quality movie (Godzilla was, after all, one of the stalwarts of 1950’s era B-rated sci-fi flicks, so you have to appreciate it for what it is). It’s just that the original (Japanese) version made a little more of a political statement about the effects of nuclear testing and the nuclear age in general. The more recent version sweeps most of the politics under the rug (blaming the French instead of the Americans for creating Godzilla, for instance) and appears satisfied to just be a corny monster movie. I could live with that except that our goal this week is to consider the role movies play in shaping and reinforcing people’s opinions about scientific issues. Nuclear power is one such issue. By some estimates 27% of Americans say they fear nuclear power, even though a far smaller percentage actually understand it at even a rudimentary level.

Assignment: Write a blog entry on how you perceive nuclear power. Do the pros of: 1) relatively cheap energy and 2) energy independence outweigh the cons of: 1) nuclear waste disposal and 2) safety concerns. What factors have influenced your thinking? What about nuclear weapons? Do you feel they have a role in modern warfare or are they too devastating to actually use? Do you favor the development of “tactical” nuclear weapons (low yield devices intended for use on the battlefield) or is that too likely to provide further impetus for other countries to develop and use nuclear weapons? Movies about nuclear armageddon were popular during the Cold War, but the theme has fallen out of favor in Hollywood in the last couple decades. Do you think a nuclear holocaust could happen in today’s world? Under what scenarios?

Please post your response on your blog by Monday, 27 Oct.

I thought I’d share a link to a physics blog a colleague pointed me to today. The blog is called “Cocktail Party Physics.” You might enjoy reading the post on “Prime Time Science” which reviews the science content of many current prime-time television shows.

Ch. 5 – Don’t Try this at Home
Ch. 17 – ISMP

Ch. 4 – Don’t Try this at Home
Ch. 15 – ISMP

There is plenty of bad physics in this movie, just like “The Core”. Enough that we could make another assignment of just trying to find as many examples as we can. Instead, though, I want to shift gears a bit with this assignment. Rather than looking at a bunch of different specific examples of science in this movie, I want you to focus on the overarching science in the movie – that of global warming. Clearly this is a controversial issue, at least among the public and politicians; scientists are mostly in agreement about the problem, although not necessarily about the potential impact or how to solve it. One of the problems seems to be that, although the bulk of the reliable scientific evidence points toward the reality of global warming and man’s role in it, there are occasionally studies released that appear to contradict this conclusion or scientists who are willing to speak out against this conclusion. However, none of these counter-claims has ever been able to produce as compelling and large a body of evidence against global warming as that in support of it. The naysayers only a few small anecdotal pieces of evidence that seem to point the other way. For unscrupulous politicians and others who have vested interests in the status quo, however, this is usually all they need. People (particularly non-scientists) are willing to discard mountains of evidence that go against their opinions in favor of a much smaller body of evidence that support them. This is a very illogical way to make decisions, but it happens all the time. This is a great week to discuss this issue because on Thursday, during class, Dr. Terry Richardson from here in the Physics department will come in to lecture exactly on the topic you are to be writing on – the science and policy of global warming. Also, on Thursday at 12:15 in our usual classroom, the Physics Colloquium speaker will be a former CofC graduate who now works as a Regional Climate Extension Specialist, whose job it is to try to bridge the gap between the science of global warming and the policy. I encourage all of you to attend that talk if you can.

Assignment: Analyze and discuss the movie “The Day After Tomorrow” from the perspective of how did/does this movie and others like it affect public discourse and opinion on the topic of global warming. Does the movie present any compelling and accurate information or arguments? You may also want to consider the role that documentaries, such as “An Inconvenient Truth”, play. Is there any evidence that either of these movies affected public opinion? Is that a good thing or a bad thing?

Bad physics:
1. The wavelength (and speed) of sound changes when it passes from one medium to another, but not the frequency.
2. Birds don’t have enough mass or fly fast enough to have the momentum required to break through a piece of glass.
3. The shuttle does not spin around nearly as quickly as portrayed. The amount of angular momentum involved would require a huge (and perfectly timed) thruster burn. The real thing would be done much more gradually. You’ve watched NASA television, right?
4. The Earth does not have an electric field, only a magnetic one.
5. THE BIG ONE: Angular momentum conservation requires that if the Earth’s core stop spinning, something else must take up the angular momentum lost by the core. In the movie angular momentum apparently can just disappear. I don’t know if the movie’s numbers are right, but the movie even claims that there are “a trillion tons of hot metal moving at 1000’s of miles per hour”. That’s a lot of momentum.
6. OK, another big one: conservation of mass. What happens to all the matter that makes up the rock that the laser obliterates. Even if the laser completely vaporizes the rock, that vapor has to go somewhere.
7. An explosive charge inside the Earth would not restart its rotation. Again, conservation of angular momentum must apply and angular momentum can only change whenever a torque is applied. An explosion inside Earth would not create a torque.
8. When they break through the “geode” the terranauts would be in freefall. They would “float” like astronauts, not dangle in their seatbelts.
9. Not quite sure how walking from compartment to compartment works with the whole gimbal system…
10. Microwaves don’t fry the planet, though they are pretty useful for making a quick bag of popcorn. Also, your cell phones work in the microwave band. They are not particularly harmful and certainly the intensity of microwaves from the Sun is not enough to do any damage (microwaves make it right through the Earth’s magnetic field and atmosphere, anyway).
11. Just having some extra plutonium around is not going to make a nuclear bomb stronger.

Obviously I let a few bad physics examples pass. I tried to just concentrate on some of the really big ones.

Good physics:
1. An electromagnetic (EM) pulse could disrupt all electronics within some specified radius. However, the only weapon that is known to create an EM pulse this large is a nuclear bomb, which creates many things other than just an EM pulse. [FYI, a supposed prototype EM pulse weapon was used by Ocean's gang in the movie "Ocean's 11" to knock out the electricity in Las Vegas.]
2. Earth’s auroras are the result of the interaction between the solar wind, the Earth’s magnetic field, and the Earth’s atmosphere. Changes in our magnetic field would affect the auroras over time.
3. The Earth does have a crust, a mantle, and a core made of two components: a solid inner core and a molten outer core.
4. The deepest humans have ever penetrated inside the Earth’s surface is 2 miles (significantly less than the 7 miles claimed in the movie). The point, though, is that we have barely even scraped into the crust. The mantle goes down to a depth of 1800 miles or so, hundreds of times deeper than we’ve ever gone.

Good/Bad physics:
1. Some birds do navigate using the Earth’s magnetic field. However, this is for long-distance navigation, not to fly around in a public square. I doubt birds would suddenly start flying into objects even if the Earth’s magnetic field suddenly changed (birds can see after all).
2. The solar wind is not “radioactive particles and microwaves”. It’s made of ions, protons, and electrons. But the Earth’s magnetic field does deflect the solar wind away from the Earth.

This is another movie we probably won’t officially review this semester, but I wanted the library to have a copy on hand. For car enthusiasts, it’s probably a must-see. For a physics class, you might think there’s not much to work with here. To some extent that’s true, but the movie does have one great physics scene: a 120 or so foot jump of a 1967 Shelby Mustang GT over the top of a traffic accident on the Vincent Thomas bridge in Los Angeles (view a clip of this scene on the Nicholls State U. website here). In the context of a “Physics in Film” class this scene is remarkable for one particular reason: it serves as the perfect contrast to the infamous bus jump scene in the movie “Speed” (view clip here). In “Gone in 60 seconds” the jump is depicted in a physically plausible (if highly dangerous) way; the car takes off with an appropriate launch speed and angle to make the jump and follows a realistic trajectory (we’ll analyze this scene in class), whereas the jump in “Speed” is not at all possible as portrayed in the movie. “Why does it matter?” you may ask. Maybe it doesn’t, but I would counter with the question, “If you can do the scene realistically and still make it exciting, why wouldn’t you?” For me, the scene in “Gone in 60 seconds” left me feeling “Wow!” The danger of the jump fits in with the plot – Randall Raines (Nicolas Cage) has already demonstrated he’s willing to give up everything (even his own life) to save his brother. If it’s going to take a nearly impossible jump over a log-jam of cars and emergency vehicles, so be it! The scene in “Speed,” on the other hand, left me feeling, “Oh, come on.” The plot is ludicrous as it is (a psycho ex-cop decides to hold a city hostage by booby-trapping a transit bus?), but the bus jump scene pushes the movie completely outside the realm of possibility. That’s not what I’m looking for in my action movies. So, my question to you is, why do Hollywood directors choose to film impossible scenes rather than construct equally exciting ones that are at least physically plausible? I think “Gone in 60 seconds” demonstrates emphatically that physically realistic scenes can still be exciting.

Another scene in this movie worth considering from the perspective of “Physics in Film” is the one where the police SUV gets knocked through the wall by the wrecking ball. It’s probably not realistic to think that the SUV would actually go through the wall (or that the cop involved wouldn’t have been more seriously hurt). Clearly that was a special “Hollywood” wall. Still, the scene was presented somewhat tongue-in-cheek. I mean consider the dialog following the scene:

G.R.A.B. special agent: “Are you alright?”
Patrol cop: “I think so.”
G.R.A.B. special agent: “Are you sure? ‘Cause you just went through a wall.”

Personally, I’m willing to forgive some lapses in physical reality, especially when they’re presented in a way that’s clearly not meant to be taken seriously, as in this scene.

This movie gets my vote for the worst movie physics of any of our feature films this semester; it even got ISMP’s vote as the #1 worst physics movie they’ve ever reviewed. To me, the bad physics is made even worse by the fact the movie takes itself way too seriously; there is very little humor; and I just don’t find myself connecting emotionally with any of the characters. So…

Assignment: The physics in this movie is so bad, your assignment is to try to keep track of all the physics blunders in the movie. You don’t have to work out all the details of why the physics is wrong, just give a brief description of each bit of bad physics you find in the movie. If you think you’ll need help, start by reading the ISMP review.

Please post your response on your blog by Monday, 29 Sep.

Ch. 14 – ISMP

OK, there are plenty of things to criticize in this movie from a physics perspective, but at least they get off on the right foot. The opening sequence describes pretty well the event most scientists believe killed off the dinosaurs (they even have the asteroid hitting the Earth in the correct location). It’s also true that something like this will happen again someday. After that, things get pretty sketchy to put it mildly. Of course, there is the obligatory destruction of NY City, even though the likelihood of a few stray meteorites hitting one of the largest cities on Earth are remote to say the least (remember 70% of the Earth’s surface is covered with water, so most likely the meteoroids are going to hit an ocean). Still, I find this movie entertaining. To me it never appears to take itself too seriously and there are some very humorous scenes. I’ll admit to even getting caught up in the stories of heroism and personal sacrifice. But when it comes right down to it, NASA’s plan to save the world (as portrayed in the movie) is pure bunk; it just wouldn’t work as we’ll discover in class.

Assignment: Come up with a plan of your own to save the Earth; hopefully one that will work. Remember, this scenario (asteroid collision threatening all humanity) will happen sooner or later, so it would be good to have a working plan. You can adjust any of the following variables you like: how much time you have, how big the meteoroid is, what it is made of, how massive it is, how dense it is. You cannot, however, adjust the fact that on final approach to Earth any meteoroid will be traveling at roughly 25,000 mph (1.1×10⁴ m/s – the escape velocity at the surface of the Earth). So, tell me, how are you going to save mankind? If you’re stuck, I encourage you to brainstorm with other members of the class.

Please post your response to your blog by Monday, 22 Sep.