Misconceptions About the Universe • 2014 Veritasium

Category: Astronomy
Download:

The expanding universe is a complicated place. During inflation the universe expanded faster than light, but that's something that actually happens all the time, it's happening right now. This doesn't violate Einstein's theory of relativity since nothing is moving through space faster than light, it's just that space itself is expanding such that far away objects are receding rapidly from each other. Common sense would dictate that objects moving away from us faster than light should be invisible, but they aren't. This is because light can travel from regions of space which are superluminal relative to us into regions that are subluminal. So our observable universe is bigger than our Hubble sphere - it's limited by the particle horizon, the distance light could travel to us since the beginning of time as we know it.

Veritasium • 2014 • 2 episodes •

Can You Solve This?

How do you investigate hypotheses?

Math

Misconceptions About the Universe

The expanding universe is a complicated place. During inflation the universe expanded faster than light, but that's something that actually happens all the time, it's happening right now. This doesn't violate Einstein's theory of relativity since nothing is moving through space faster than light, it's just that space itself is expanding such that far away objects are receding rapidly from each other. Common sense would dictate that objects moving away from us faster than light should be invisible, but they aren't. This is because light can travel from regions of space which are superluminal relative to us into regions that are subluminal. So our observable universe is bigger than our Hubble sphere - it's limited by the particle horizon, the distance light could travel to us since the beginning of time as we know it.

2014 • Astronomy

You might also like

Mystery of Planet 9

Examining a ninth planet that may be on the outer edge of the solar system. Scientists speculate that it could be 10 times the size of Earth and have moons capable of hosting life.

S5E2How the Universe Works • 2016 • Astronomy

The Day We Walked on the Moon

On July 16, 1969, hundreds of thousands of spectators and an army of reporters gathered at Cape Kennedy to witness one of the great spectacles of the century: the launch of Apollo 11. Over the next few days, the world watched on with wonder and rapture as humankind prepared for its "one giant leap" onto the moon--and into history. Witness this incredible day, presented through stunning, remastered footage and interviews that takes you behind-the-scenes and inside the spacecraft, Mission Control, and the homes of the astronaut's families.

2018 • Astronomy

Secrets of Time Travel

A look at the concepts behind changing the way we travel through the space-time continuum, and how extreme speed and extreme gravity can change the rules of the game.

S8E5How the Universe Works • 2020 • Astronomy

The Search for a Second Earth

Is there another Earth out there with liquid oceans, rocky continents and life like us? Astronomers seek the answer with spectroscopy, direct imaging and telescopes. They hope to find evidence of atmospheres, magnetospheres and signs of life.

S3E9How the Universe Works • 2014 • Astronomy

Hubble's Amazing Journey

The most amazing images of the universe captured by the space telescope, and a look at plans to launch a new and more advanced satellite in 2018. In this updated version of "Hubble's Amazing Journey” we reveal some of Hubble's latest observations: It has produced some of the most awe-inspiring images ever taken of the universe. But what is often forgotten about the Hubble Space Telescope is that after its launch 25 years ago it was originally labelled an embarrassing and expensive flop.

2016 • Astronomy

The Physics of Life

Our universe is prone to increasing disorder and chaos. So how did it generate the extreme complexity we see in life? Actually, the laws of physics themselves may demand it.

PBS Space Time • 2018 • Astronomy