Traffic: The Science Behind Why Slower Cars Always Catch Up

Published: 01 April 2026. The English Chronicle Desk. The English Chronicle Online.

Every motorist knows the unique sting of frustration that comes with a sudden red light. You find a rare gap in the urban crawl and safely overtake a slower vehicle. Your engine roars briefly as you pull ahead into the open space of the road. However, your triumph is often short-lived when the next junction turns a bright crimson. As you sit idling, that same slow car rolls quietly up to your rear bumper. It feels as though the universe is playing a cruel joke on your hurried commute. This common occurrence has finally been explained by a fascinating new mathematical study from Ireland. Dr Conor Boland from Dublin City University has formally named this the Voorhees law of traffic. The name draws inspiration from the silent antagonist of the famous Friday the 13th films. Jason Voorhees is known for his slow, methodical pace while his frantic victims sprint away. Despite their speed, the killer always seems to appear right behind them in the end. In our modern world, traffic lights serve as the obstacles that halt our frantic escape. Boland published his findings in the esteemed journal Royal Society Open Science to widespread academic interest. He used complex equations to model how two cars interact across a network of lights. The research focuses on the spacing between vehicles as they navigate various light signal cycles. Spacing can increase, stay the same, decrease, or vanish entirely based on several specific factors. These factors include light duration, the time advantage of the faster car, and cycle patterns. For a single light, the study found that gains and losses balance out quite perfectly. This means that on average, the lead of the faster car remains remarkably stable over time. If this is true, why does it feel like we are always being caught? Boland suggests that our human brains are simply wired to remember these specific annoying encounters. We tend to ignore the times we successfully pull away and never see them again. Psychology plays a massive role in how we perceive our progress through a busy city.

When we are overtaken, our egos often feel a slight bruise from the other driver. Seeing that same car at the next light provides a sense of smug satisfaction. This creates a lasting memory that reinforces the idea of a law of traffic. However, the mathematics changes significantly when a driver faces a long string of traffic lights. In a city environment, catching up becomes a statistical certainty rather than a random chance. The probability of never being caught drops with every single new junction you might encounter. If you pass ten lights, the odds of a slower car reaching you are high. This happens because the slower car only needs to catch up at one single signal. Once the gap is closed, the time advantage of the faster driver is totally lost. For the faster car to stay ahead, they must beat every light in the sequence. This requires a level of luck that most urban road networks simply do not allow. Consequently, the aggressive driver often gains nothing but a higher bill for their fuel. Speeding between junctions rarely results in a significantly faster arrival at a final destination. Dr Boland hopes his work will encourage more patience and safety among all UK drivers. Professor Kit Yates from the University of Bath also shared his thoughts on the study. As a self-described slower driver, he finds the results to be both charming and validating. He often watches faster cars speed away only to meet them at the next stop. There is a quiet joy in realizing that hurrying often serves no practical purpose. Yates noted that the study makes a few simple assumptions to keep the math clear. It assumes cars travel at constant speeds without the usual lag of starting or stopping. In the real world, reaction times and acceleration also play a role in traffic flow. Even with these simplifications, the core message of the research remains very powerful and true. All models are limited, but this one is useful for explaining a universal driving truth. It reminds us that the rhythm of the city is set by the lights. No matter how much we hurry, we are all part of the same flow. The next time you are overtaken, just wait for the next red light ahead. You will likely see your speedy friend waiting there for the very same green. Patience on the road is backed by science and leads to a calmer life. We can all learn to drive a bit more like Jason Voorhees today. Just keep moving steadily and let the lights do the work for your journey. Safe driving is about timing and logic rather than just pure engine power alone. UK roads would be much safer if we all accepted this mathematical reality together. Understanding the Voorhees law might just save you some unnecessary stress tomorrow morning. Every red light is an equaliser that brings the whole world back into balance. So take a deep breath and enjoy the music on your car radio. You will get where you are going at the same time anyway, eventually. Mathematics has proven that the race is not always won by the fast. It is won by those who understand the inevitable patterns of the modern road.