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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

#111

Post by alfiedotwtf »

lubujackson wrote: post #92
AnimalMuppet wrote: post #69

Earlier quoted context omitted.

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

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

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

#112

Post by dwroberts »

an0malous wrote: post #94
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.

> 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. Is this actually stated somewhere by the institutions that take taxpayer money for this research, or just your opinion?

If you’re talking about taxpayer money and you’re in the United States, maybe a better starting point is the ‘jobs program’ they’re running for military personnel

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

#113

Post by Erem »

sigmoid10 wrote: post #108
Erem wrote: post #65

Earlier quoted context omitted.

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

Imaginary numbers are a helpful tool for calculating things in our universe. All these holographic theories and their insights are based on a universe that behaves basically opposite to ours.

From Wikipedia, imaginary numbers...

> Originally coined in the 17th century by René Descartes[4] as a derogatory term and regarded as fictitious or useless, the concept gained wide acceptance following the work of Leonhard Euler in the 18th century, and Augustin-Louis Cauchy and Carl Friedrich Gauss in the early 19th century.

I think the jury is still out wrt utility of AdS spaces. They could be useless toys, or they could be in the Descartes phase rn.

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

#114

Post by bobbylarrybobby »

lubujackson wrote: post #92
AnimalMuppet wrote: post #69

Earlier quoted context omitted.

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

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?

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

#115

Post by izucken »

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…

Should call the next big physics thing doubtscumbagium...

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

#116

Post by __turbobrew__ »

djsamseng wrote: post #99
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.

If the sun is on my left, doesn’t that mean time moves a bit slower on my left and the slowdown on the left means I’ve traveled less on my left side? Thus I turn left toward the sun.

I believe that is correct.

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

#117

Post by throwaway894345 »

AnimalMuppet wrote: post #103
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.

One nit: Time moves a bit slower on the sun's side. Other than that, thank you for a very clear explanation.

If a particle was dropped into the sun’s gravity (not with “horizontal” motion that might cause it to orbit), is it time dilation that causes it to accelerate toward the sun somehow?

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

#118

Post by chowells »

mixmastamyk wrote: post #104
nilkn wrote: post #88

Earlier quoted context omitted.

That's right -- the atmosphere stays attached to the Earth mostly thanks to gravity, and the Earth's gravity in GR is almost entirely the gradient in clock rate near the Earth. Near Earth’s surface, clocks lower down tick very slightly slower than clocks higher up. The change in tick rate is on the order of 10^(-16) per meter. While extremely small, that's enough to generate the familiar 9.8 m/s^2 spatial acceleratio…

I’ve seen this described before in terms of how GPS is able to do what it does, so not surprising. But still haven’t explained why time would so dominate the space dimension. Edit: The response below is dead for some reason, please vouch.

Everything we experience is far larger in time than space, so of course time effects dominate on scales we perceive.

But this just raises the question of what it means to be larger in time than space. You can look at it in terms of multiples of Planck distance or time, but I think there's a more enlightening way to look at it. If you express the speed of light in those Planck units, it's 1. But the speed of light is also the maximum speed of causality. Any causally-bound system must run long enough for chains of causation to propagate, usually far below the speed of light in practice. This means that basically anything that exists within the bounds of our manipulation must be happening at scales where there is far more time involved than space.

We all exist below the diagonal because the diagonal is the bound at which the ways chemistry and biology work no longer even are theoretically possible.

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

#119

Post by izucken »

wasabi991011 wrote: post #78
yxhuvud wrote: post #13

Earlier quoted context omitted.

Not just the headline. Is it possible to take any scientist talking about something they term as magic seriously?

Would you prefer "non-Cliffordness"? Does using words that are more of a mouthful make scientist more credible?

Absolutely. "non-Cliffordness" by consturction already implies "Cliffordness", which by construction implies "Clifford" and then connects other related things. Magic doesn't do that exactly, but instead slips unnecessary connections. Clifford as a name relates to a matematician who was probably dead by the time anyway. It is considerably more neutral as a name and "free" of unrelated context. I am not knowledgeable about it, but I also wouldn't be suprised if Clifford works are also related to mathematical facilities in quantum theories where the name is invoked.

When trying to understand the reality and then convey that understanding, "mouthfulness" seems like not a concern at all.

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

#120

Post by ck2 »

wizzwizz4 wrote: post #75
AnimalMuppet wrote: post #69

Earlier quoted context omitted.

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

All objects move through spacetime at the speed of light, but a stationary object is moving in the time direction. (And the time dimension has opposite sign to spatial dimensions, so (Lorentzian) rotation's effect on length works opposite to what you'd expect from Euclidean rotations: https://commons.wikimedia.org/wiki/File:Spacetime_diagram_of... .) Suppose we drop a test mass from the top of the leaning tower of Pi…

it's the speed of causality (limit of information transfer)

https://www.youtube.com/watch?v=8yhk1EZq9tY

fortunately that video is more gentle but the math in that youtube channel absolutely melts my brain some days, I can keep up for the first minute but then all bets are off as he dives in and I realize there are some insanely brilliant people out there

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