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The distances between the stars are so vast that they can make your brain melt. Take for example the Voyager 1 probe, which has been traveling at 35,000 miles per hour for more than 40 years and was the first human object to cross into interstellar space. That sounds wonderful except, at its current speed, it will still take another 40,000 years to cross the typical distance between stars.

Worse still, if you are thinking about interstellar travel, nature provides a hard limit on acceleration and speed. As Einstein showed, it's impossible to accelerate any massive object beyond the speed of light. Since the galaxy is more than 100,000 light-years across, if you are traveling at less than light speed, then most interstellar distances would take more than a human lifetime to cross. If the known laws of physics hold, then it seems a galaxy-spanning human civilization is impossible.

Unless of course you can build a warp drive.

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The Einstein-Bohr legacy: can we ever figure out what quantum theory means?

Quantum theory has weird implications. Trying to explain them just makes things weirder.

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  • The weirdness of quantum theory flies in the face of what we experience in our everyday lives.
  • Quantum weirdness quickly created a split in the physics community, each side championed by a giant: Albert Einstein and Niels Bohr.
  • As two recent books espousing opposing views show, the debate still rages on nearly a century afterward. Each "resolution" comes with a high price tag.
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My UFO experience

Like Fox Mulder, people have a lot of strong opinions about UFOs.

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  • Extraordinary claims, such as that UFOs have visited our planet or that aliens exist, require extraordinary evidence.
  • Personal testimonies are simply insufficient to conclude that UFOs and aliens are real.
  • Good luck having a rational conversation about it with anyone on Twitter.
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What happened before the Big Bang?

Asking science to determine what happened before time began is like asking, "Who were you before you were born?"

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  • Science can allow us to determine what happened trillionths of a second after the Big Bang.
  • But it likely never will be possible to know what brought about the Big Bang.
  • As frustrating as it might be, some things are entirely unknowable. And that's a good thing.
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How do we know the sun is a star?

Today, it's common knowledge, but it took scientists centuries to figure out.

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  • The simplest questions are often the hardest to answer.
  • At first blush, the sun and stars are very different. The former is close and hot, the latter far away and cold.
  • We couldn't confirm the sun to be a star until telescopes and spectroscopes were invented.
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The incredible story of Wu Hsin and Roy Melvyn

Must a religious story be confirmed as a true fact to be effective and inspiring?

Wu Hsin

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  • Wu Hsin is an allegedly ancient Chinese sage whose inspiring teachings were brought to light by an obscure character named Roy Melvyn.
  • Wu Hsin's teachings have inspired millions of people across the globe — even if all evidence indicates that he never existed and was made up by Melvyn.
  • The remarkable story of Wu Hsin and Roy Melvyn explores the conflict between the nature of faith and literal or interpretative readings of religious texts.
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