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Entanglement Builds Space-Time. Now "Magic" Gives It Gravity

quantamagazine.org

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Re: Entanglement Builds Space-Time. Now "Magic" Gives It Gravity

#61

Post by zchrykng »

dwroberts wrote: post #12
sigmoid10 wrote: post #3

>In holographic theories, physicists may have traced the pliability of space-time to its quantum roots ...ah yes holography again. Not to say that all these insights from it are completely worthless, but unless we actually find a holographic dual of our universe instead of AdS spaces (which are the opposite of our universe if anything), this whole field is starting to feel more like a jobs program for mathematicians…

> this whole field is starting to feel more like a jobs program for mathematicians out of new ideas. So sick of seeing phrases like this. Science is not business. It is not about producing results that you personally think are important. It is understanding the nature of the universe for the sake of it.

Please enlighten us how purely theoretical mathematical constructs, that are impossible to test, help us understand anything about our universe.

Re: Entanglement Builds Space-Time. Now "Magic" Gives It Gravity

#62

Post by zchrykng »

MeteorMarc wrote: post #48
echelon wrote: post #32

Earlier quoted context omitted.

Is any of this experimentally testable in the real world? Would gravity or spacetime under these definitions behave differently and yield something we can observe? Or is this fancy math modeling that looks nice on paper, but that we won't be able to test until we become a Kardashev type III civilization?

See the end of the article, after further research quantum gravity could be simulated on a quantum computer. The links between research on quantum computing and quantum gravity are fascinating anyway!

Simulating it on a computer, even a "quantum computer", is not the same as testing it against actual reality.

Re: Entanglement Builds Space-Time. Now "Magic" Gives It Gravity

#63

Post by krapp »

lioeters wrote: post #50
lloeki wrote: post #21

Earlier quoted context omitted.

Is it measured in Thaum? (which, as everyone surely knows by now is the amount of magic needed to create one small white pigeon or three normal-sized billiard balls)

> The thaum is the basic unit of magic. The thaum is made up of so called resons, which are themselves made up of at least five flavours including up, down, sideways, sex appeal and peppermint.

400 billion dollars and a portal to hell later scientists discover evidence of the elusive spearmint.

Re: Entanglement Builds Space-Time. Now "Magic" Gives It Gravity

#65

Post by Erem »

zchrykng wrote: post #61
dwroberts wrote: post #12

Earlier quoted context omitted.

> this whole field is starting to feel more like a jobs program for mathematicians out of new ideas. So sick of seeing phrases like this. Science is not business. It is not about producing results that you personally think are important. It is understanding the nature of the universe for the sake of it.

Please enlighten us how purely theoretical mathematical constructs, that are impossible to test, help us understand anything about our universe.

Imaginary numbers are purely theoretical, but they turn out very helpful in almost every engineering discipline

Re: Entanglement Builds Space-Time. Now "Magic" Gives It Gravity

#66

Post by wasabi991011 »

Terr_ wrote: post #2

> a measure of quantumness known as “magic.” This naming-proposal couldn't possibly cause any problems down the line... > They had worked out a way of running software on a classical computer that would mimic a quantum task. When it comes to using a regular computer to mimic (read: fake) the execution of an exotic program/API for nonexistnet future hardware, I highly recommend the humorously titled talk: "Temporally…

> This naming-proposal couldn't possibly cause any problems down the line...

You're a little late here, "magic" is already a fairly well known term in quantum computing literature. There's "magic states" and protocols for "magic state distillation" and "magic state injection", there's "shallow magic depth circuits", etc.

Re: Entanglement Builds Space-Time. Now "Magic" Gives It Gravity

#67

Post by nilkn »

"Einstein cast gravity not as a force but as the geometric bending of space and time. In a popular analogy, the fabric of space-time is like the flat expanse of a mattress, and a massive object like a star is like a bowling ball sitting on top. The weight of the bowling ball compresses the mattress, forming a dimple — matter tells space-time how to curve.

In this analogy, a planet is like a smaller ball. If it rolls close enough to the bowling ball, its path will be altered by the dimple in the mattress — space-time tells matter how to move."

This analogy is wrong in a way that even people who've studied physics often don't realize.

On an everyday scale like the Earth orbiting the Sun, almost none of that gravitational interaction is from the bending of space. Far beyond 99% (actually, about 99.999999%) of it is from the bending of time.

Re: Entanglement Builds Space-Time. Now "Magic" Gives It Gravity

#68

Post by IsTom »

seanhunter wrote: post #53
apothegm wrote: post #14

That is an incredibly unfortunate term to use for the phenomenon.

I agree, although there is a long tradition of terrible naming in the sciences. One of the most boring and yet egregious examples imo is "Random Variable". So named because - they aren't random and - they aren't variables.[1] A "random variable" is actually a measurable deterministic function from the set of possible outcomes of some experiment to the real numbers. But you can see why the name "random variable" is co…

> A "random variable" is actually a measurable deterministic function from the set of possible outcomes of some experiment to the real numbers.

I don't think that this was the formalization that was used when the term was coined, given how late set and measure theory were formalized.

Re: Entanglement Builds Space-Time. Now "Magic" Gives It Gravity

#69

Post by AnimalMuppet »

nilkn wrote: post #67

"Einstein cast gravity not as a force but as the geometric bending of space and time. In a popular analogy, the fabric of space-time is like the flat expanse of a mattress, and a massive object like a star is like a bowling ball sitting on top. The weight of the bowling ball compresses the mattress, forming a dimple — matter tells space-time how to curve. In this analogy, a planet is like a smaller ball. If it rolls…

Could you be more specific? How does bending time cause the Earth to orbit the Sun?

Re: Entanglement Builds Space-Time. Now "Magic" Gives It Gravity

#70

Post by camel_gopher »

nilkn wrote: post #67

"Einstein cast gravity not as a force but as the geometric bending of space and time. In a popular analogy, the fabric of space-time is like the flat expanse of a mattress, and a massive object like a star is like a bowling ball sitting on top. The weight of the bowling ball compresses the mattress, forming a dimple — matter tells space-time how to curve. In this analogy, a planet is like a smaller ball. If it rolls…

Aka the Einstein tensor
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