Secrets of the Cosmic Microwave Background

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Hook up an old antenna to your TV and scan between channels. The static buzz you hear is mostly due to the ambient radio produced by our noisy pre-galactic civilization. But around one percent of that buzz is something very different – it’s the cosmic microwave background radiation – the remnant of the heat-glow released when the hot, dense early universe became transparent for the first time. It sound likes random static, but that buzz contains an incredible wealth of hidden information. It holds the secrets of the universe’s fiery beginning,

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Sound Waves from the Beginning of Time

Hosted by Matt O'Dowd
Written by Matt O'Dowd
Graphics by Luke Maroldi
Directing by Andrew Kornhaber

It’s not surprising that scientists have spent half a century and built multiple satellites to unlock the mysteries of the cosmic microwave background. We’ve delved into its nature before – from its formation 380,000 years after the Big Bang, to its 1964 discovery by Penzias and Wilson with the Holmdel Horn Antenna, to its increasingly accurate mapping across the sky with ever-better satellites. It all culminated in this – the Planck satellite’s map of the CMB.

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سلطان الخليفي

[seanmortazyt]

I admire the audacity of you guys even /attempting/ to explain such advanced topics and actually succeeding.

[Dwrnold]

where discovery channel makes me bored out of my skull. this channel leaves me in the fetal position rocking back and forth.

best content on youtube.

[fobusas]

The amount of stuff scientists can figure out from something like CMB is unbelievable. And how it all comes together, independently verifying each other... Congratulations on very clearly presented video!

[DanielZajic]

This was one of my favorite episodes ever. I'm amazed how we're able to find out so much from what seems like so little evidence.

[darkdoescosplays]

One thing I love about these videos is that, even where the content gets more advanced than my current knowledge, they're explained in such a way that it's possible to understand the abstract concepts. Which also then makes it much easier to fill in the gaps of my knowledge. This is a brilliant series, and a great public service. Thank you.

[alyasgrey]

I will never fail to be amazed at the depth of measured and modelled evidence for the models of the universe, and frankly everything 'established' in cosmology.

Anyone who doesn't appreciate the work put in by cosmologists and other professions involved in cosmology simply does not understand the multitude of information they account for. Thank you for everything, scientists and support workers.

[leaturk]

That was one of the best explanations I've had the pleasure of listening to.

[technocore]

I’ve watched all of these videos and when you mentioned the geometry of the universe before you explained what that meant I knew it referred to whether triangles are 180deg or not!!! It seems the primary benefit of watching SpaceTime videos is being able to understand SpaceTime videos! 🤣🤣🤣

[emiliavlahos]

i have spent the last 2 days trying to understand this for my midterm tomorrow and this is the only helpful explanation i have found online. Thank you i feel so enlightened

[Aidan]

PBS Space Time has to be the absolute best Science communicator I've seen. They don't really dumb things down in any significant measure and Matt is always careful to set the record straight to avoid falsely hyping things as the media so often does (ie. "That star over there might have an alien megastructure" one of my favorite examples of the media's clickbaiting pranks)

[danielhenderson]

Sometimes I feel like I'm keeping up with you and I'm like "yes OMG, go on.."and then I get distracted for a spit second and I've lost it. I love this channel, and I love even half understanding what you say half the time. Don't ever leave :)

[nathandaniel]

Thanks man, you are one of my big motivations to get into astrophysics and particle physics. I'm currently at university and these videos still boggle my mind. Like "baryon-photon plasma" when I heard that I almost yelled "WHAT?!" I haven't even studied QM or relativity yet but I'm mind boggled at the idea that the speed of light is the same in all inertial reference frames. Physics YouTuber like yourself absolutely make me crave my textbooks Just to be able to understand why things do thing.

[danclaydon]

We truly are blessed to have channels like this.

[miriamgonczarska]

Wow your programs, are becoming better and better! Thank you so much! Fascinating :)

[avov]

Proud supporter of pbs spacetime. Ive watched every vid

[J.Rod_Drums]

I wish I'd've known that the Physics skill tree is required to unlock the Wizard class....

[ThEpitapH]

the music you guys have had in the videos for the past couple weeks has been great. really nice touch, and subtle enough to not distract.

[carsonmyers]

"In that noise can be found, the secrets..."
oh yeah here it comes
"of the earliest epochs..."
wait wtf
"of space time."
YOU TRICKED ME

[pumpupthevolume]

How this was even put into a coherent presentation is mind blowing which doesn't even scratch the surface on the science that went into figuring all this out. I am humbled.

[Verlisify]

Finally. A Space time I can understand