The NEW Crisis in Cosmology

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I have good news and bad news. Bad news first: two years ago we reported on the Crisis in Cosmology. Since then, it’s only gotten worse. And actually, the good news is also that the crisis in cosmology has actually gotten worse, which means we may be onto something!

The most exciting thing for any scientist is when something they thought they knew turns out to be wrong. So it’s no wonder that many cosmologists are starting to get excited by what has become known as the Hubble tension, or the crisis in cosmology. The “crisis” is the fact that we have two extremely careful, increasingly precise measurements of how fast the universe is expanding which should agree with each other, and yet they don’t.

Original Crisis in Cosmology

Sabine Hossenfelder's episode "Do we travel through time at the speed of light?"

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Hosted by Matt O'Dowd
Written by Matt Caplan & Matt O'Dowd
Graphics by Leonardo Scholzer, Yago Ballarini, Pedro Osinski, Adriano Leal & Stephanie Faria
GFX Visualizations: Katherine Kornei
Directed by Andrew Kornhaber
Assistant Producer: Setare Gholipour
Executive Producers: Eric Brown & Andrew Kornhaber

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[savandesouza]

Sometimes I lament the loss of my job due to covid, but combined with a reignited passion for physics and astronomy from this inspiring channel, I'm going back to school to pursue a different degree. Thank you Matt and all the fantastic digital artists of PBS!

[ravenatorful]

Love this quote: "Love being wrong, because finding the source of that wrongness can only lead to greater understanding."

[JonKukur]

"Baryon acoustic oscillations" has to be one of the most Star Trek phrases spoken on this channel.

[meinbherpieg]

"The most exciting thing for any scientist is when something they thought they knew turned out to be wrong" - this is also the most depressing thing for any student taking a test.

[mjhzen]

Glad to know Cosmology is in a crisis; it can join the rest of us.

[joecaves]

The cosmological constant, constantly changing.

[DanielTaylorOCMD]

The beginning of this video reminded my of Carl Sagan's quote about scientists -
“In science it often happens that scientists say, 'You know that's a really good argument; my position is mistaken, ' and then they would actually change their minds and you never hear that old view from them again. They really do it. It doesn't happen as often as it should, because scientists are human and change is sometimes painful. But it happens every day. I cannot recall the last time something like that happened in politics or religion.”

[Rep]

All my t-shirts and mugs from the 80s are now too small. Clearly showing how the Universe has expanded since then.

[jouhannaudjeanfrancois]

it's 1AM and according to my latest measurements, the distance between the couch and my bed has augmented

[joesphmontgomery]

I think we should give this “giant space ruler” a more legitimate effort.

[jgseg]

Bro, your ability to explain complex concepts in a simple and elegant way is remarkable. I've been learning quite a lot, thank you very much!

[Mitch-gudz]

7:12 Thank you for recognizing that I am too lazy to hold my finger up in front of my face.

[michaelupdike-bzrg]

As much as I love theoretical work you gotta hand it to those experimentalists for making my life harder and harder.

[chrisb]

"It is increasingly clear there is a hole in our understanding of the universe, " is such an understatement.

[stapler]

If the acceleration of expansion was different at different points in time, you might say the universe has been quite a jerk.

[DrPOP-jpeb]

I love the fact that "Dark Energy", "Red Dwarf", "Supernova" are all real scientific terms. JRR Tolkien could not have come up with anything better.

[mkism]

The UK has been rough today. So nice to have these fascinating and barely comprehensible videos to escape into.

[mugin]

A crisis in science, is always a good thing. It means we learn new things.

[MagnaMater]

Dear me, I fell asleep, the Algorithm choose what I should sleep to, but I woke on somebody telling me about 'duck energy'. I had to scroll backwards, and the energy turned out to be only dark, not duck, but at the same time much stranger than a LED powered by ducks could ever be.

[verdatum]

Stormtroopers _never_ miss. They are just firm believers in the utility of the warning shot.