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Time Dilation and Intergalactic Travel

Could You Upload Your Brain?

A new model suggests that the early universe may have contracted and expanded&mdash;at the same time.

A new model suggests that the early universe may have contracted and expanded—at the same time.

Do We Live in an Anamorphic Universe?

What is The Nature of Reality? It’s a blog, and it’s pretty much the biggest question we could think of. We can’t promise that we’ll answer the question once and for all – in fact, we can pretty much guarantee that we won’t – but we promise a space that welcomes big ideas about space, time, and the universe; where we take questions as seriously as we take answers; where physics is about way more than inclined planes and levers and pulleys. Stick around; we just might expand your cosmic horizons.

What is The Nature of Reality? It’s a blog, and it’s pretty much the biggest question we could think of.

The Nature of Reality

What is The Nature of Reality? It’s a blog, and it’s pretty much the biggest question we could think of.

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Time dilation is possibly the weirdest part of Einstein’s Theory of Special Relativity. According to time dilation, the faster you travel, the slower your time moves. But why does this happen? It’s actually a result of the fact that light always travels at the same speed, regardless of one’s frame of reference.The first of these two videos describes how the constancy of the speed of light implies the existence of time dilation. The second video explains how time dilation allows for intergalactic travel, and in this case to the Andromeda Galaxy.Time Dilation Explained:Intergalactic Travel &amp; Time Dilation:

The discovery that light gets redder as its source moves away from Earth led astronomers to uncover some of the universe’s strangest truths, including dark energy, dark matter, and the expansion of the universe.How well can you read these five clues and decode the universe’s best kept secrets?

5 of the Biggest Puzzles about the Universe

Just over a century ago, even the most pioneering astronomers still pictured the universe as a small, static thing that ended at the edges of the Milky Way Galaxy. But that all changed after an Indiana farm boy discovered a strange quirk of the cosmos in 1912: redshift.Over the course of a century, redshift, the shifting of light toward the red end of the spectrum, became a tool that led astronomers to uncover some of the biggest cosmic mysteries — and to discover the incredible breadth of the universe itself.

How Redshift Revealed the Universe

What the Physics?!, hosted by Dr. Greg Kestin, a theoretical physicist at Harvard University, is about the physics in you, the physics of you, and the physics around you.If you’ve been enjoying our videos, <a href="http://youtube.com/whatthephysics">find us on YouTube</a> to catch up on old episodes or subscribe to find out about new ones.

What the Physics?! Trailer

In 1998, astronomers hoped to discover whether the universe would expand forever or eventually collapse under its own gravity. What they found instead shattered every expectation: something was overpowering the pull of gravity and pushing the universe apart.They called it dark energy. But what is this invisible substance that makes up more than 70% of our universe? And what does it mean for the future?<div>
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What Is Dark Energy?

What would it take to make a copy of your brain?With the days of blurry mimeographs behind us and the technology to make copies spreading into 3D- and cyberspace, the possibilities might seem almost limitless. But are they?Physics itself—not technology, not human ingenuity—forbids perfect cloning, which might throw a kink in your plan to upload your brain.

Imagine the Earth gets swallowed by a black hole. Then, like all black holes, this one slowly evaporates away as particles radiate from its event horizon, until—poof—there’s nothing left.What happens to everything that has fallen in? Has it just been deleted from the universe? Could information somehow escape from behind the event horizon? Or did it never truly fall in in the first place?Ultimately, no one knows—and each one of these three unlikely answers breaks physics as we know it.

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Time Dilation and Intergalactic Travel

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Could You Upload Your Brain?

Do We Live in an Anamorphic Universe?

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Time Dilation and Intergalactic Travel

5 of the Biggest Puzzles about the Universe

How Redshift Revealed the Universe

What the Physics?! Trailer

What Is Dark Energy?

Could You Upload Your Brain?

The Black Hole Information Paradox