How do you know when it’s finally time to pack up and move on, to just go for it? Some will encourage you, but what if you’re not ready, and fall flat on your face?

This ancient mathematical trickery posits that a mighty hero cannot overtake a tortoise. Zeno of Elea (born c. 490 BCE) is the author of this and other paradoxes.

The more you think about it, the more complex time travel seems! This video explains a key paradox that is one of the main reasons for this.

John Searle's thought experiment, called "The Chinese Room," presents an argument against the idea that computers could ever be truly intelligent.

If a hotel with an infinite number of rooms has an infinite number of guests, how could it free up space when new guests arrive? Hilbert's “Grand Hotel” paradox has fascinated mathematicians, physicists, philosophers, and theologians, as it encourages another way of thinking about the notion of infinity.

How can one brother travel into space and return younger than his twin? In just sixty seconds, a startling side effect of Einstein’s Theory of Relativity is explained to us.

Schrodinger’s hypothetical experiment involved putting an unfortunate cat into a box with a Geiger counter and a vial of deadly poison. Until the box was opened, the cat could be said to be alive, or dead… or possibly in both of these states simultaneously.

In a heartfelt cry for change and equality, 4 Non Blondes despair of the status quo and of the suppressive conventions they face up to in adult life. It’s hard to believe that this was their only major hit. What’s going on?!

This is grunge band 3 Doors Down with their song “When I’m Gone”. Happy listening!

Automobile Magazine associate editor Greg Migliore gives you a first look at the all-new 2015 Chevrolet Corvette Z06.

PopTopic TV: Rihanna is up for an amazing 18 awards this year, including the evening’s coveted Top Artist award. She started things off with her racy ‘S&M’ single, clad in a barely there, white patent leather dominatrix ensemble, slithering across the stage at the MGM Grand Garden Arena in Las Vegas on Sunday night.

69 million children remain out of school, efforts must be increased by leaders around the world to ensure every child has the chance for an education by 2015. This video summarising the work of the 1GOAL campaign so far was shown at the UN Millennium Development Goals Summit in New York.

Brothers Dudley and Chris had the honor of being part of the first ever Jamaican bobsled team, competing at the nineteen eighty-eight Winter Olympics. We hear the true story of how this unlikely team came into existence, and how Chris went from being a spectator to an Olympic competitor with less than a week’s training.

Decades later, the events of the nineteen eighty-eight Winter Olympics seem harder and harder to believe, even to the men at the heart of the original Jamaican Bobsled team. But it really did happen, and the proof is in the strong sporting and commercial legacy they leave for the next generations.

The charming Natalie Merchant of the American rock band 10,000 Maniacs sings the song “Like the Weather,” which honestly and clearly reflects on a sad mood.