What Are Time Crystals? The Strange Matter That Ticks
When I first heard the phrase “time crystals”, I pictured something from Doctor Who. The reality is stranger, and sadly has nothing to do with time travel. So what are…
Mass vs Weight: What Is the Difference?
Ask most people their weight and they will give you a number in kilograms. To a physicist, though, that answer is technically a measure of mass, not weight. So what…
Is Zero an Even Number? Yes. Five Ways to Prove It
Yes, zero is an even number. It is not odd, it is not both, and it is not some special third category that sits outside the rules of arithmetic. Zero…
Are Black and White Colours? It Depends on Light or Paint
It sounds like a trick question from a primary school quiz. Are black and white colours? The honest answer is that it depends on whether you are talking about light…
Speed vs Velocity: What Is the Difference?
In everyday conversation, “speed” and “velocity” mean pretty much the same thing. In physics, they are different, and the difference between speed and velocity comes down to one thing: direction.…
Is Time Travel Possible? Yes, but Only One Way
Who hasn’t daydreamed about skipping ahead a few centuries to see the future, or slipping back to fix a mistake? So, is time travel possible? Surprisingly, partly yes. Travelling into…
What Is Static Electricity? And Why You Get Zapped
You walk across the carpet, reach for a door handle, and zap. Or you slide out of the car on a dry day, touch the door, and get a sharp…