Was the Gravitational Wave Background Finally Discovered?!?

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A few weeks ago a large team of gravitational wave astronomers announced something pretty wild. The moderately confident detection of pervasive ripples in the fabric of space time that presumably fills the cosmos, detected by watching for subtle connections between the signals from rapidly spinning cores of dead stars in our galactic neighborhood. In other words, the gravitational wave background has probably been detected using a pulsar timing array.

Thumbnail Image Illustration Credit: Olena Shmahalo for NANOGrav

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Hosted by Matt O'Dowd
Written by Matt O'Dowd
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00:00 Introduction
01:02 Relativity and Gravitational Waves
02:21 Discovering Gravitational Waves
03:49 Gravitational Waves & Pulsars
05:04 Pulsar Timing Array Discovers GWB
06:48 Understanding the GWB
07:55 Are Pulsars Seeing Gravitational Waves?
09:00 Correlated & Anti-Correlated Pulsar Rates
10:07 Hellings and Downs Curve
11:44 Binary Supermassive Black Holes
13:39 NANOgrav Frequency Spectrum

[igortolstov]

Kudos to the team responsible for visual effects on this channel. They do amazing work

[himynameis]

I just love how you guys can communicate science to the layman such as myself. Ye make everything so accessible. I dunno, i reckon that ye deserve an award of some sort. Its always interesting and i always learn something new and fascinating. Thank you for the hours of entertainment and education. Favourite channel by far

[SeanGhaeli]

I'm so happy this channel is still around, it was a driving force for my interest in physics back in high school 6 years ago. Fast forward to today and I'm less than a year away from getting a degree in engineering physics

[some_words]

Love the Anton and Dr. Becky shoutouts. Anton in particular deserves all the love.

[dragonslayerslayerdragon]

Your graphical representations are phenomenal.

[minotaurbison]

It tickled me to see my other favorite science youtuber, Anton, in your video. You both are awesome creators!

[Jhary]

While I did watch Dr. Becky's video first, it's important to get the information from multiple sources...

I'm happy you referenced her, as that's added evidence of the quality of her channel. Thank you.

[gehteuchnichtsan]

this makes so much sense to me. that's why the universe on a macro scale looks like the light reflections of surface of water in motion, like a pool or something.

[newrever]

This channel continues to be among the very best on YouTube! Thanks so much for making these amazing discoveries a little more accessible to all of us!

...also, galactic gigawhale t-shirts when?

[LaunchPadAstronomy]

As always, I'm blown away by your visual and written explanations. You are the channel I want to be when I grow up.

[rby]

Channels like this are so important because monumental discoveries like this are otherwise buried in the noise that is our grasping pop culture soup. I’m constantly appalled that you never see coverage of these stories in mainstream media. (I’d say news but we don’t really have mainstream news sources anymore other than local newspapers.)

[marcusw]

Not to be *that* guy, but I know you value accuracy, so I have to point out that LIGO first detected gravitational waves in September 2015, not 2016. I say this with all humility and want to close by telling you how much I really love and appreciate what you do at Spacetime- thank you for opening new worlds to those of us who otherwise would not have access 🙂

[diabendoindia]

Fantastic- the animations and explanations are literally and figuratively out of this world

[gheckolock]

I've always believed in galactic giga whales. So glad to see space time positing a theory of their existence.

[mj.ray]

I've been really interested in all the discoveries and space missions that have been happening the last several years, and channels like this one help so much to understand this stuff without needing a degree in quantum physics or something. Thanks for these!

[daxmasterflex]

My favorite is when YouTubers reference other YouTubers similar videos, knowing their audience has probably seen said videos instead of bickering about who did it first or best.

[yourguard]

Omg, Matt has super massive black holes close to his heart?😱
Sounds dangerous....and bad ass.

[nathangek]

This is genuinely one of the best channels I know on YouTube. Thank you for producing such high quality astrophysics content.

[cabanford]

Wow! I actually could follow an entire episode 🎉🎉🎉

Love your channel (thanks for throwing the occasional "softball" 🤗)

[garyfilmer]

Wibbly-Wobbly right through the universe, it all vibrating waves, rippling through space-time. This gravitational wave background is fascinating, we have come such a long way in our understanding of the universe, thank you, excellent video.