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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

#71

Post by taeric »

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…

To be fair, it isn't that different from why we have imaginary numbers. Or why the reals are calls reals.

Which. Yeah, has been a pretty bad thing for people in understanding those. :(

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

#73

Post by stuff4ben »

AnimalMuppet wrote: post #69
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?

And also, how does one bend time?

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

#74

Post by wasabi991011 »

greenbit wrote: post #31

Greek 'anameixi' loosely means a mixture or a blending. The special states could be called 'anameixic', the property could be called 'anameixicity'. Why am I trying to find a name for this? Otoh, why are so many physicists trying so hard to popularize their projects for the last 40 or 50 years? Oh .. I think I just answered my own question.

Are you suggesting "anameixi" to replace "magic"?

But magic is related to non-Cliffordness, not mixing.

Also, the term "magic" is pretty well used in quantum computing, it really doesn't need to be popularized. The concept is quite important already and would be talked about regardless of its name.

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

#75

Post by wizzwizz4 »

AnimalMuppet wrote: post #69
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?

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 Pisa. The "forwards through time" direction takes the object deeper into the local gravity well: as far as the test mass is concerned, it's just moving forwards through time according to Newton's First Law, and everything else is accelerating towards it for no apparent reason.

It may help your intuition to consider the extreme case of a black hole. The event horizon is where time is so warped that no possible future trajectories lead outside of the black hole, and you need a magical time machine to escape. (Of course, the best way to gain intuition is to work through the mathematics, either symbolically or with diagrams, rather than reading English-language descriptions.)

There is a sense in which an orbit is a straight line. Obviously, an orbit is not a straight line through space (unless you count the perfect and unobtainable orbit of a beam of light around a black hole, some distance from the event horizon), but we often think of them as spirals through spacetime: there's an argument that really we should think of them as straight lines through spacetime, much like how a great circle is a straight line along the earth's surface.

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

#76

Post by CuriouslyC »

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.

I didn't say all his theories were garbage, though the theories inspired by them developed by laypeople almost certainly are. I just don't find his argument compelling enough on its face to warrant holding them up as real progress.

Also, remember that Isaac Newton was deep into alchemy and religious prophecy. Just because you have one good idea and you're smart enough to follow it to its logical conclusion doesn't mean every idea you have is good.

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

#77

Post by wasabi991011 »

greenbit wrote: post #26

Calling something 'magic' is like an admission that you have no clue about what is going on. Seems to me, they do have some clue, namely that instead of codes with perfect isolation, there might be some advantage to studying ones that allow some blending. The resulting spaces may (or may not) lead to a better description of reality, but doing science means to peel back that mystery. So to go and promote this under th…

They are not "promoting" the term magic. It is a well-known and commonly used term in quantum computing research. It is also pretty well understood as a concept (mathematically), even if it's not always easy to recognize in nature or easy to know when it needs to be used in algorithms.

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

#78

Post by wasabi991011 »

yxhuvud wrote: post #13
tetrisgm wrote: post #5

I gotta say every aspect of this headline reads like bullshit. Unfortunately

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?

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

#79

Post by nilkn »

stuff4ben wrote: post #73
AnimalMuppet wrote: post #69

Earlier quoted context omitted.

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

And also, how does one bend time ?

It means clocks tick at different rates depending on where they are.

Imagine spacetime as a field of local clocks. Far from the Sun, clocks tick faster. Near the Sun, clocks tick slower. A freely moving object tries to follow the straightest possible path through spacetime. But because the “time axis” changes from place to place, what counts as “straight ahead into the future” tilts slightly inward near the Sun. So the Earth’s path through spacetime curves toward the Sun.

Earth’s spatial speed around the Sun is about 30 km/s. But through spacetime, its “timeward” motion is basically c, 300,000 km/s. So even a tiny tilt in the time direction creates a significant spatial acceleration. That is why the time-warping term dominates for slow massive bodies.

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

#80

Post by marcosdumay »

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.

Let he go first and start arguing for this one with reason. If he insists on using discredited ideas that are known not to lead to the results he insists on, name-calling is an appropriated response.
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