Is Gravity RANDOM Not Quantum?

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The holy grail of theoretical physics is to find the long-sought theory of quantum gravity. But what if this theory is as mythical as the grail of legend? What if gravity isn’t weirdly quantum at all, but rather … just a bit messy? Or random? So says the postquantum gravity hypothesis of Jonathan Oppenheim.

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Hosted by Matt O'Dowd
Written by Christopher Pollack, Lorenzo Braccini, & Matt O'Dowd
Post Production by Leonardo Scholzer, Yago Ballarini & Stephanie Faria
Directed by Andrew Kornhaber
Associate Producer: Bahar Gholipour
Executive Producers: Eric Brown & Andrew Kornhaber
Executive in Charge for PBS: Maribel Lopez
Director of Programming for PBS: Gabrielle Ewing
Assistant Director of Programming for PBS: John Campbell

Spacetime is a production of Kornhaber Brown for PBS Digital Studios.
This program is produced by Kornhaber Brown, which is solely responsible for its content.
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[lightfish]

We got Oppenheim and Oppenheimer, but Openheimest is still missing.

[novigradian]

The intro was louder than the big bang lol

[summersnooze]

“Oh sweet 😊 time for a nice relaxi—“

BOOOM BOOODOOODOOO BOOOM BOOOOM

😱🤯🫥

[spladam]

Audio guy making sure Space Time has your attention.

[YossiSirote]

I think it is important to note that Oppenheim’s theory is testable. That is a great advantage compared to many other attempts. Hopefully within a decade or so it will be tested and we will know if this idea is correct or not.

[MarshmallowRadiation]

This feels less like a revolutionary mind-bending theory-of-everything and more like a funny math trick to get things to work together that really shouldn't, with some strange logical side effects that don't seem likely to be physically real but still somehow could be.

Which, given the history of physics, means that is is probably a major breakthrough. An "oops I thought the Planck constant would reduce to zero but I accidentally quantized the electromagnetic field" moment. A "let's balance out this equation with a positively-charged electron going in reverse like some kind of 'anti-matter'" moment.

[TehPwnerer]

You gotta talk to your audio guy about levels and keeping them relatively consistent. Can barely hear you in the start, crank up the volume & then get my head blown off by the intro 🤯

[K.F-R]

Douglas Adams and/or Terry Pratchett would be having so much fun with this.

[Nono-dezi]

I love it. 35 years of studying and modeling biomolecular mechanisms led me to view all such as biased stochastic processes. How randomness can lead to apparent determinism is underestimated.

[llywyllngryffyn]

You don't have 'An' apple moving toward the Superposition Earth, you have a Superposition set of Apples moving toward a Superposition set of Earths. Collectively it functions like a Classical system.

[jajssblue]

2:07 I still wish we could have a video deep diving into how naive quantization of GR fails mathematically. Everyone just waves their hands and says that it causes non-sensical singularities in the equations.

[falxonPSN]

That last comment about Eve online being spreadsheets in space hit hard. I used to run a multi-hundred person corporation (and later alliance) and it literally became actual work.

[toad]

Ive determined the volume of the intro was randomly as loud as possible

[MarcoLogan]

It's incredible that after so many years this show can still deliver such amazing episodes. One of the best I remember, absolutely intriguing.

[sechran]

[Einstein] "God does *not* play dice with the universe!"
[God Making Gravity] "Whoo! Yahtzee!"

[lookatdatcake]

How funny, I just sat in on a talk by a fields medalist who explained how continuous brownian motion has a lot of parallels to gravitational fields

[mikelastname]

I've always thought I was clumsy, but actually, random gravity does a great job of explaining why I fall over at such incomprehensible times and places.

[spidalack]

Seriously, your voice is super quiet and the theme almost made my ears explode

[lloyddomke]

Old school THX system REALLY let me know there was some dynamic range to the intro music. Going to peel my cat off the ceiling now.

[cineblazer]

As a machine learning researcher, stochasticity in gravity feels pretty intuitive to me. I'm a big fan of Oppenheim's theory!