Gaming’s Top 5 Busted Laws of Physics

Virtual worlds tend not to have a close relationship with the order of the natural universe. Considering the enormous complexity modern physics uses to describe the governances of reality, it’s perhaps not surprising that the limited worlds coded by humans often have difficulty providing accurate replication of many physical principles. As someone who’s studied physical sciences for a long time, aspects of gaming worlds that violate well established natural principles can sometimes stick out like a sore thumb. I compiled the following list as a fun, only marginally serious examination of these inaccuracies. A lot of these exist for good reasons related to game design and the experience that is trying to be crafted, but others exist as the result of either intentional or unintentional oversight.

 

5. Sound needs a medium to propagate

Issue: There is no sound in space.

This one is a bit of a low-hanging fruit that is mentioned constantly, and it is a scientific faux pas that permeates science fiction and space opera across the range of audiovisual arts. From Star Wars and Trek to Wing Commander, Starcraft and a whole lot of shmups, loud boisterous explosions and other exciting clamors are often heard reverberating through the vacuum of space during the great clashes of star faring factions. Of course, space is permeated by an incredibly low pressure of gas (density is roughly on the order of a few atoms per cubic meter), which simply cannot carry sound as depicted by these great space epics. The intention is of course clear, as these sounds are used to convey the calamity of battle. I’ve always wondered though, what would a space battle feel like without the din of war? I actually think it might be a little creepy and unsettling to watch starships zip through the emptiness of space, unleashing blazing munitions on each other, and bursting into balls of fire all in deafening silence.

 

4. First Law of Thermodynamics

Issue: Energy is neither created nor destroyed.

This one is a little more complicated, so stick with me here for a moment. Depending on how you look at it, respawns violate this law, as well as how enemy bodies just sort of vanish after they die. When your character dies, say in Unreal Tournament or something modern like Halo, a new body for the player just sort of magically materializes out of the ether. This is a violation of conservation of energy, as new matter (which is linked to energy by Einstein’s famous equation) is spontaneously generated during such an event. You may be able to argue around this one if, perhaps, the player’s former body disappears at the same time as the player respawns, so that total quantity of matter doesn’t change. And while in a lot of shooters dead bodies tend to disappear after a short amount of time which allows for matter to eventually be balanced, the contradiction of thermodynamics is far more definite in RPGs like Diablo, where the player actually goes off on corpse runs to recover loot off of their mortal remains.

There are of course obvious game design reasons for a character to miraculous rematerialize after death, and it is a topic that has been discussed in more existential and philosophical terms when relating to the impermanence of death in video games. Another violation of this law is the hammer space that so many video game characters seem to have access to. Character inventories are often rarely visually depicted as being on their person. When they draw a gun or an item it usually just materializes out of thin air. One glaring example of this that gave me a chuckle was in Metal Gear Solid 4 when Solid Snake carries a large oil drum to conceal himself in. When drawn from his inventory, suddenly this oil drum that is wider than Snake and almost as tall suddenly just appears. It’s a lot easier to suspend disbelief when only relatively small items like guns and health packs vanish and reappear at will.

 

3. Coulomb’s Law

Issue: Like charges repel, unlike charges attract.

Coulomb’s Law is the inverse square law that governs the forces that electrical charges exert on one another. It is also at least partly the reason that solid objects cannot pass through one another. When two atoms are forced into close proximity, electron clouds from each atom begin to overlap and the negative charges repel each other (the Pauli Exclusion Principle also plays a role here). There are of course countless situations in video games where solid objects briefly exist in the same place at the same time. A common example is in multiplayer shooters where often members of the same team can pass through one another with great ease. Other examples are those kinds of walls that can be walked through to gain access to secret areas, or how when a player takes damage in a sidescroller they are usually given a few frames of invincibility that allow them to cross enemies unharmed. The reasons for these things are of course clear. Players can pass through teammates to make less hassle, secret hiding places in games are just fun, and invincibility frames keep enemies from trapping players and becoming one hit kills.

 

2. Newton’s First Law of Motion

Issue: An object in motion tends to stay in motion. An object at rest tends to stay at rest.

This is a big pet peeve of mine in a lot of video games, especially platformers. Consider what happens if, say, you were riding a train and decided to jump straight up. In the real world, you will land in roughly the same spot on the train as you jumped (assuming the train is travelling at a constant speed in a constant direction). This is a result of Newton’s First Law of Motion; essentially it is your inertia that would keep you moving in the same direction as the train, not the friction of your feet on the train floor.

In a lot of games, this is not what happens. In many games, if, say, your character is riding a moving platform, jumping straight up will cause the character to remain in the same horizontal position relative to the screen, not relative to the platform. Essentially your character flies backwards relative to the moving platform. Even games lauded for quality, such as the Super Mario Bros. 3 and Sonic the Hedgehog, suffer from this bizarre distortion of Newtonian mechanics. Half-Life has an example of this that has always hit a nerve with me. In the start of the game while riding the tram into Black Mesa, if you press the spacebar and jump, Gordon goes flying backwards and slams into the back of the tramcar. It’s sort of a hilarious “bug” for a game about a MIT-graduated physicist working in a high-level government research program.

Unlike double jumping or sound in space, there’s not necessarily a good reason for this to occur in the game. It is more a product of crude coding (or perhaps a bad understanding of motion) than a functional game design choice, and, unlike the others on this list, the sheer way in which this one annoys me gives it a place here.

 

1. Newton’s Third Law of Motion

Issue: For every action, there is an equal and opposite reaction.

The principal violator of this law is air control, but double jumping violates this principle as well. What would games be without air control, a complete violation of Newton’s Third Law of Motion? When in midair, a human (or humanoid) has very little ability to control their trajectory without some sort of wings or propulsive equipment, yet Mario, Megaman, Sonic, and most sidescrolling heroes have the uncanny gift of being able to slide midair in whatever horizontal direction they please. Not only that, but it is often required they perform this fantastical feat to complete their quests. There are a few occurrences of sidescrollers where this is not allowed, Castlevania and Another World come to mind. In these games, the spot you’ll land is entirely determined by the spot (and forcefulness) of your jump, as it would be in the real world. This, of course, can be used to make games more challenging and methodical, sometimes for the better, sometimes for the worse.

This one ranks at the top of the list because it just makes games so much more amusing. Remember the parts in Megaman games where you’re falling and have to slyly maneuver yourself through a curving pit of wall to wall spikes? What would Mario or Sonic be like if you couldn’t alter your course midair by just a little bit to perfectly land on that goomba or badnik?   Super Meat Boy’s in-flight agility is what makes that game so enjoyably fast and fluid. I could go on with countless examples of how air control is just fun. So while it’s not accurate, it’s highly appealing. Which is fine, as slavish devotion to reality needn’t be a requirement for a good virtual world.