Do parallel universes really exist?

Remember that traffic accident you avoided the other day? In another universe, you died. Or at least you did according to the Many-Worlds theory. Explore some sticky questions.

Has a surfer discovered the theory of everything?

Surfer and physicist A. Garrett Lisi may have solved one of physics' greatest mysteries -- the theory of everything. It's a mathematical link to how the universe works.

How Exploding Manholes Work

Manhole covers have been blasting out of the ground in New York City. Find out what causes these strange explosions and how powerful they really are.

How Magnets Work

Magnets are used in all kinds of applications, but do you ever wonder exactly why it sticks to certain metals? Find out the answer to this and other questions as we explore exactly how magnets work.

How many regular-sized helium-filled balloons would it take to lift someone?

How many regular-sized helium-filled balloons would it take to lift someone? What is the equation to figure it out?

How Pi Works

Pi is an extremely interesting number that is important to all sorts of mathematical calculations. Did you know it can be calculated without the use of circles? Find out how you can calculate it yourself.

How Quantum Cryptology Works

Swiss citizens recently cast their parliamentary election votes, which were transmitted using quantum cryptology, a method of encoding and decoding voting data using photons.

How Quantum Suicide Works

A man has a gun. But this is no ordinary man, and this is no ordinary gun. This isn't a setup for a sci-fi thriller. It's the premise for quantum suicide. What exactly is quantum suicide?

How Special Relativity Works

Special relativity deals in phenomena that don’t agree with our historical or commonsense views of how the universe works. In fact, many of the theory’s assertions almost appear ludicrous. Yet, there have been several observations that agree with Einstein’s predictions.

How Teleportation Will Work

Looking forward to instantaneous travel? The Star Trek teleporter is one step closer to reality. Scientists have now teleported a laser beam. Could humans be next?

How Time Works

Ever wonder why we start our year on the first of January? Or why we have January and the other 11 months in the first place? Find out all about time.

What if I forgot to remove a piercing before an MRI?

The magnets found in an MRI machine are incredibly powerful. It can pull a stethoscope right out of a doctor's lab coat. So what would happen if you forgot to take out an earring? Ouch!

What if I threw a penny off the Empire State Building?

You might have heard the tale about a person who, standing on the observation deck of the Empire State building, throws a penny and kills a pedestrian on the sidewalk below. Does this story have any truth to it?

What if someone shot a gun on an airplane?

There are lots of scenes in movies where terrorists or hijackers take over an airplane and start shooting up the place. Wouldn't the plane explode or depressurize as soon as the bullet hit the skin of the airplane?

What if two people stumbled into quicksand: Would the heavier person sink faster?

We've all seen it in the movies: A guy stumles across quicksand, and before we know it, he's waist deep and can't get out. Does Hollywood have it all wrong?