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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

#121

Post by kridsdale1 »

alfiedotwtf wrote: post #111
lubujackson wrote: post #92

Earlier quoted context omitted.

Imagine you are driving in a car coming up parallel to the sun on your left. Time moves a bit faster for you on the left side than the right side. This slight speedup makes your left side traverse space faster than the right side, which causes a slight drift to the left (and also makes you spin). Now just add massive scale and distances.

I’m going to ask the obvious next question… so if the sun and me in the car are next to each other but stationary, where is the attraction coming from now? As in, time may make the closer side slower, because we’re stationary, there’s no drift etc

You always have to define stationary when it comes to relativity.

There is no way to have a “zero speed orbit”. You’d be on a trajectory straight in to the middle of the sun or away from it (under your own power). The only way to stop is to push away with equal constant acceleration (which looks like “force”). This is what rockets do.

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

#122

Post by colordrops »

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…

I never liked the mattress analogy, because if gravity is the bending of the mattress, what is pulling the ball down the slope?

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

#123

Post by Retric »

bobbylarrybobby wrote: post #114
lubujackson wrote: post #92

Earlier quoted context omitted.

Imagine you are driving in a car coming up parallel to the sun on your left. Time moves a bit faster for you on the left side than the right side. This slight speedup makes your left side traverse space faster than the right side, which causes a slight drift to the left (and also makes you spin). Now just add massive scale and distances.

How does this cause a point particle to accelerate towards the sun? Must be something about the gradient, but how does the gradient of time cause you to curve towards the sun?

With QM there’s no pure point particles.

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

#124

Post by russdill »

bobbylarrybobby wrote: post #114
lubujackson wrote: post #92

Earlier quoted context omitted.

Imagine you are driving in a car coming up parallel to the sun on your left. Time moves a bit faster for you on the left side than the right side. This slight speedup makes your left side traverse space faster than the right side, which causes a slight drift to the left (and also makes you spin). Now just add massive scale and distances.

How does this cause a point particle to accelerate towards the sun? Must be something about the gradient, but how does the gradient of time cause you to curve towards the sun?

A point particle? You mean that useful mathematical approximation for excitations in a field?

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

#125

Post by CamperBob2 »

an0malous wrote: post #54
CuriouslyC wrote: post #19

Earlier quoted context omitted.

Blame Roger Penrose for the microtubule bullshit. Ironically, he's the opposite of new age, dude won a Nobel prize.

Maybe, just maybe, an eminent physicist who won the Nobel Prize knows more than us. At the very least his ideas deserve consideration instead of ridicule and dismissal. Also as far as I know, Penrose’s main argument is that consciousness can not be computational. If you can’t argue against an idea with reason and resort to name calling, you’re not being rational you’re just being dogmatic and censoring ideas.

Penrose's argument isn't rational itself, so I don't see why a rational argument should be required in order to dismiss it. As CuriouslyC points out, quantum consciousness is the equivalent of Newton's dalliances with alchemy and astrology.

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

#126

Post by twoodfin »

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…

What’s an example where it would be accurate to say 99%+ of the interaction is from the bending of space?

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

#127

Post by CamperBob2 »

an0malous wrote: post #58
bawolff wrote: post #55

Earlier quoted context omitted.

https://en.wikipedia.org/wiki/Nobel_disease

Again, if you disagree with Penrose’s idea, just explain your disagreement. It’s so ironic how you’ll call it bullshit and link to some pop culture skeptic idea with no scientific backing to try and undermine an idea in defense of “real science” > Another approach is to follow that word, heresy. In every period of history, there seem to have been labels that got applied to statements to shoot them down before anyone…

Again, if you disagree with Penrose’s idea, just explain your disagreement.

We can now simulate every aspect of consciousness except for long-term memory consolidation, to the extent that you can't tell if you're talking to a conscious person or a computer. The existence of LLMs means that no quantum woo is necessary to explain consciousness. Our brains just do the same thing by different means.

In short, Penrose's argument is a religious one, not a scientific one.

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

#128

Post by yubblegum »

wvbdmp wrote: post #41
yubblegum wrote: post #15

Earlier quoted context omitted.

You mean post quantum, theoretical physics. Up to 19th and early 20th, physicists somehow knew how to name things. It is possible that the nature of the beast itself has changed and it attracts a different kind of mindsets ...

Maybe Greek and Latin vocabulary is just overextended at some point? I don’t really see the issue with Snap, Crackle and Pop. The potential confusion around Magic seems much greater, although when you consider the vastly more common opposite effect, where specific scientific terms become popular and quickly gain wholly different colloquial meanings, perhaps it doesn’t really matter in the grand scheme of things. Perh…

> Maybe Greek and Latin vocabulary is just overextended at some point? I don’t really see the issue with Snap, Crackle and Pop.

What is "overextended" imho is an actual understanding of what these phenomena really are. Previously, we had some sense of what we meant by e.g. field or atom or electron, quantum, ...

So yea, if we don't know enough about the thing we're naming, we might as well pull random strings out of a hat and in that case "pop, snap, crackle, strange, charm, fifi, doodoo, woof, & meow" (note these latter 4 are my contributions to advancements of human understanding btw /g) are good enough!

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

#129

Post by zehaeva »

colordrops wrote: post #122
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…

I never liked the mattress analogy, because if gravity is the bending of the mattress, what is pulling the ball down the slope?

It's just an analogy, you're not supposed to think too deeply about them.

The main take away for a lay person is that _like_ the mattress space is being deformed. That's where the analogy stops. Taking it further, like with all analogies, breaks the analogy.

If the analogy was a perfect one, then it would just be the reason and not an analogy.

My main gripe is how hard for most people it is to extrapolate that deformed mattress into a 3d space.

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

#130

Post by whatshisface »

bobbylarrybobby wrote: post #114
lubujackson wrote: post #92

Earlier quoted context omitted.

Imagine you are driving in a car coming up parallel to the sun on your left. Time moves a bit faster for you on the left side than the right side. This slight speedup makes your left side traverse space faster than the right side, which causes a slight drift to the left (and also makes you spin). Now just add massive scale and distances.

How does this cause a point particle to accelerate towards the sun? Must be something about the gradient, but how does the gradient of time cause you to curve towards the sun?

That's a great question. The answer is, the stuff you are reading in this thread is not right (you figured it out). The real version of the story is, there is this thing called the "Christoffel symbol," which tells you where, at every point in space, you would end up if you went in a certain direction, including which way you would be facing if you went that way. It relates three vectors: your direction of motion, the direction you are currently facing, and the delta to your direction of facing that would result from taking that direction of motion.

If you let your current momentum be your direction of facing, and let the same momentum also specify your direction of motion, the Christoffel symbol tells you what your momentum vector would be after an infinitesimal amount of motion. This can be integrated to find the version of a straight line appropriate for a curved surface (imagine an ant walking straight forwards on the surface of a cone or something), a geodesic. A changing momentum is like a force is acting, so that's gravity.

There is more to learn than that, of course. Many many many books have been written about general relativity and you can read them.

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