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Post Reply Is there a genius that could theorize space time structure?
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Posted 4/14/18 , edited 4/15/18


No Fred. Your faulty human eyes perceive in 3 dimensional. Spacetime is 4 dimensional. As far as "force" is concerned; spacetime does not contain a force per say. There are four fundamental forces to discuss though.






Gravity (Relativity)

In general relativity, gravity is not a force between masses. Instead gravity is an effect of the warping of space and time in the presence of mass. Without a force acting upon it, an object will move in a straight line. This is where one would have to be even more studious in General Relativity to discuss how the electromagnetic/weak/strong forces influence the Riemann curvature of spacetime?

In GR, the answer would be that all of these forces contribute to the stress-energy tensor T, which in turn sources the Einstein tensor G through the field equations, Gab=8πTab, and the Einstein tensor is the trace-reverse of the Ricci tensor, which is a contraction of the Riemann curvature tensor. So in this sense, the forces all influence the curvature of spacetime.

Strong Force

A force which can hold a nucleus together against the enormous forces of repulsion of the protons is strong indeed. However, it is not an inverse square force like the electromagnetic force and it has a very short range. Yukawa modeled the strong force as an exchange force in which the exchange particles are pions and other heavier particles. The range of a particle exchange force is limited by the uncertainty principle. It is the strongest of the four fundamental forces

Since the protons and neutrons which make up the nucleus are themselves considered to be made up of quarks, and the quarks are considered to be held together by the color force, the strong force between nucleons may be considered to be a residual color force. In the standard model, therefore, the basic exchange particle is the gluon which mediates the forces between quarks. Since the individual gluons and quarks are contained within the proton or neutron, the masses attributed to them cannot be used in the range relationship to predict the range of the force. When something is viewed as emerging from a proton or neutron, then it must be at least a quark-antiquark pair, so it is then plausible that the pion as the lightest meson should serve as a predictor of the maximum range of the strong force between nucleons.

Electromagnetic Force
The electromagnetic force manifests itself through the forces between charges (Coulomb's Law) and the magnetic force, both of which are summarized in the Lorentz force law. Fundamentally, both magnetic and electric forces are manifestations of an exchange force involving the exchange of photons. The quantum approach to the electromagnetic force is called quantum electrodynamics or QED. The electromagnetic force is a force of infinite range which obeys the inverse square law, and is of the same form as the gravity force.

The electromagnetic force holds atoms and molecules together. In fact, the forces of electric attraction and repulsion of electric charges are so dominant over the other three fundamental forces that they can be considered to be negligible as determiners of atomic and molecular structure. Even magnetic effects are usually apparent only at high resolutions, and as small corrections.

Weak Force
The weak interaction involves the exchange of the intermediate vector bosons, the W and the Z. Since the mass of these particles is on the order of 80 GeV, the uncertainty principle dictates a range of about 10-18 meters which is about 0.1% of the diameter of a proton.

The weak interaction changes one flavor of quark into another. It is crucial to the structure of the universe in that

1. The sun would not burn without it since the weak interaction causes the transmutation p -> n so that deuterium can form and deuterium fusion can take place.
2. It is necessary for the buildup of heavy nuclei.

The role of the weak force in the transmutation of quarks makes it the interaction involved in many decays of nuclear particles which require a change of a quark from one flavor to another. It was in radioactive decay such as beta decay that the existence of the weak interaction was first revealed. The weak interaction is the only process in which a quark can change to another quark, or a lepton to another lepton - the so-called "flavor changes".

The discovery of the W and Z particles in 1983 was hailed as a confirmation of the theories which connect the weak force to the electromagnetic force in electroweak unification.

The weak interaction acts between both quarks and leptons, whereas the strong force does not act between leptons. "Leptons have no color, so they do not participate in the strong interactions; neutrinos have no charge, so they experience no electromagnetic forces; but all of them join in the weak interactions."(Griffiths)
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Posted 4/16/18 , edited 4/16/18

Shishiku wrote:



No Fred. Your faulty human eyes perceive in 3 dimensional. Spacetime is 4 dimensional. As far as "force" is concerned; spacetime does not contain a force per say. There are four fundamental forces to discuss though.






Gravity (Relativity)

In general relativity, gravity is not a force between masses. Instead gravity is an effect of the warping of space and time in the presence of mass. Without a force acting upon it, an object will move in a straight line. This is where one would have to be even more studious in General Relativity to discuss how the electromagnetic/weak/strong forces influence the Riemann curvature of spacetime?

In GR, the answer would be that all of these forces contribute to the stress-energy tensor T, which in turn sources the Einstein tensor G through the field equations, Gab=8πTab, and the Einstein tensor is the trace-reverse of the Ricci tensor, which is a contraction of the Riemann curvature tensor. So in this sense, the forces all influence the curvature of spacetime.

Strong Force

A force which can hold a nucleus together against the enormous forces of repulsion of the protons is strong indeed. However, it is not an inverse square force like the electromagnetic force and it has a very short range. Yukawa modeled the strong force as an exchange force in which the exchange particles are pions and other heavier particles. The range of a particle exchange force is limited by the uncertainty principle. It is the strongest of the four fundamental forces

Since the protons and neutrons which make up the nucleus are themselves considered to be made up of quarks, and the quarks are considered to be held together by the color force, the strong force between nucleons may be considered to be a residual color force. In the standard model, therefore, the basic exchange particle is the gluon which mediates the forces between quarks. Since the individual gluons and quarks are contained within the proton or neutron, the masses attributed to them cannot be used in the range relationship to predict the range of the force. When something is viewed as emerging from a proton or neutron, then it must be at least a quark-antiquark pair, so it is then plausible that the pion as the lightest meson should serve as a predictor of the maximum range of the strong force between nucleons.

Electromagnetic Force
The electromagnetic force manifests itself through the forces between charges (Coulomb's Law) and the magnetic force, both of which are summarized in the Lorentz force law. Fundamentally, both magnetic and electric forces are manifestations of an exchange force involving the exchange of photons. The quantum approach to the electromagnetic force is called quantum electrodynamics or QED. The electromagnetic force is a force of infinite range which obeys the inverse square law, and is of the same form as the gravity force.

The electromagnetic force holds atoms and molecules together. In fact, the forces of electric attraction and repulsion of electric charges are so dominant over the other three fundamental forces that they can be considered to be negligible as determiners of atomic and molecular structure. Even magnetic effects are usually apparent only at high resolutions, and as small corrections.

Weak Force
The weak interaction involves the exchange of the intermediate vector bosons, the W and the Z. Since the mass of these particles is on the order of 80 GeV, the uncertainty principle dictates a range of about 10-18 meters which is about 0.1% of the diameter of a proton.

The weak interaction changes one flavor of quark into another. It is crucial to the structure of the universe in that

1. The sun would not burn without it since the weak interaction causes the transmutation p -> n so that deuterium can form and deuterium fusion can take place.
2. It is necessary for the buildup of heavy nuclei.

The role of the weak force in the transmutation of quarks makes it the interaction involved in many decays of nuclear particles which require a change of a quark from one flavor to another. It was in radioactive decay such as beta decay that the existence of the weak interaction was first revealed. The weak interaction is the only process in which a quark can change to another quark, or a lepton to another lepton - the so-called "flavor changes".

The discovery of the W and Z particles in 1983 was hailed as a confirmation of the theories which connect the weak force to the electromagnetic force in electroweak unification.

The weak interaction acts between both quarks and leptons, whereas the strong force does not act between leptons. "Leptons have no color, so they do not participate in the strong interactions; neutrinos have no charge, so they experience no electromagnetic forces; but all of them join in the weak interactions."(Griffiths)





From Fred:


Yes, since we can "perceive" space time in 3 dimensions, we can re-create it in 3 dimensions. It could be a 4 dimensional structure in 3 dimensional space(I dunno what I am talking about). The point is, we can recreate this structure, it could be a string, a spiral, a pointy triangle, anything. We recreate this structure inside a computer and bang we got space time. It comes with force and with time.

But how does time and force arise out of a structure like jello? Beats me. How do you create a moving space time out of a non-moving structure, that is what I am trying to figure out. This is out of speculation but, this structure could exist, and someone could have theorized it already.

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Posted 4/16/18 , edited 4/16/18
^^^
Shots fired.

What I'll say is this, do not underestimate the power of the Human consciousness, ego and mind. Things that were once said impossible are a reality now.

Give the science community the same funding you give to murdering civilians over seas I mean the military(We're looking at you America) and enough time I'm sure you will come to realize things that are impossible now, may be possible tomorrow.

The Natural laws we observe here on our Pale Blue Dot may possibly not apply elsewhere in the Universe, we still know so little when it comes to the Universe and its true nature and functionality and we may never know unless we are given eons(hypothetical unit of time, maybe less depending on if/how fast humanity unites as a whole). Yes we can observe laws that are applicable in other parts of our Galaxy or even other galaxy's, but I can easily argue "But you can't confirm it 100% because you haven't been on the other side of the Universe to extract sufficient data to proclaim an absolute Law of the Universe.

IMO.
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Posted 4/16/18 , edited 4/16/18
From Fred:


Yes, since we can "perceive" space time in 3 dimensions, we can re-create it in 3 dimensions. It could be a 4 dimensional structure in 3 dimensional space(I dunno what I am talking about). The point is, we can recreate this structure, it could be a string, a spiral, a pointy triangle, anything. We recreate this structure inside a computer and bang we got space time. It comes with force and with time.

But how does time and force arise out of a structure like jello? Beats me. How do you create a moving space time out of a non-moving structure, that is what I am trying to figure out. This is out of speculation but, this structure could exist, and someone could have theorized it already.

Za Warudo



It is not a matter of "can" - you DO perceive in 3d. Yet reality is different from what you PERCEIVE. You can make structures in 2D does that make it a true representation of a structure? Not necessarily, not that certain models that are not true representations cannot give us insight and data, but it is still not the actual representation of the structure.

This is where we should go into Knot theories since you are implying strings and spirals - which are more advanced knot theories. & With this we will shift from real world applications and move to more mathematical theory which are not true representations of the world, yet house a lot of insight anyways. Which you should enjoy.

Witten explains how the method developed by Jones and other mathematicians for comparing knots that differ by how a missing piece is filled in has led to many links between the Jones polynomial and mathematical physics.

In quantum physics, a knot may be regarded as the orbit in spacetime of a charged particle. One way of calculating the Jones polynomial in quantum theory involves using the Chern-Simons function for gauge fields. But to use the Chern-Simons function, the knot must be a path in a spacetime of three dimensions (two space dimensions and one time dimension) rather than the four dimensions (three space dimensions and one dimension of time) of the real world. Beginning in the 1980s, efforts by Members in the School of Mathematics—primary among them Igor Frenkel, Louis Crane, and Michael Khovanov—have generalized the Jones polynomial to introduce a concept known as Khovanov homology, which allows the knot to become a physical object in four spacetime dimensions.

During the last decade, Sergei Gukov, Albert Schwarz, and Cumrun Vafa, former Members in the Schools of Mathematics and Natural Sciences, have developed a quantum interpretation of Khovanov homology. Witten spent the last year constructing his own approach, which involves Chern-Simons gauge theory and electric-magnetic duality and relates Khovanov homology to theories in four, five, and six dimensions. These quantum interpretations closely connect Khovanov homology to cutting-edge ideas about quantum field theory and string theory.

In everyday life, a string—such as a shoelace—is usually used to secure something or hold it in place. When we tie a knot, the purpose is to help the string do its job. All too often, we run into a complicated and tangled mess of string, but ordinarily this happens by mistake.

The term “knot” as it is used by mathematicians is abstracted from this experience just a little bit. A knot in the mathematical sense is a possibly tangled loop, freely floating in ordinary space. Thus, mathematicians study the tangle itself. It can be quite hard to make sense of a tangled piece of string—to decide whether it can be untangled and if so how. It is equally hard to decide if two tangles are equivalent.

Such questions might not sound like mathematics, if one is accustomed to thinking that mathematics is about adding, subtracting, multiplying, and dividing. But actually, in the twentieth century, mathematicians developed a rather deep theory of knots, with surprising ways to answer questions like whether a given tangle can be untangled.

Even though knots are things that can exist in ordinary three-dimensional space, as a physicist I am only interested in them because of something surprising that was discovered in the last three decades.

Much of the theory of knots is best understood in the framework of twentieth- and twenty-first-century developments in quantum physics. In other words, what really fascinates me are not the knots per se but the connections between the knots and quantum physics. The first “knot polynomial” was actually discovered in 1923 by James W. Alexander. Alexander, a Princeton native who later was one of the original Professors at the Institute, was a pioneer of algebraic topology. But the story as I will tell it begins with the Jones polynomial, which was discovered by Vaughan F. R. Jones in 1983. The Jones polynomial was an essentially new way of studying knots. Its discovery led to a flood of new surprises that is continuing to this very day. Even though it is very modern, and near the frontier of contemporary mathematics, the Jones polynomial can be described in such a down-to-earth way that one could explain it to a high school class without compromising very much. There are not many frontier developments in modern mathematics about which one could make such a claim. For example, no one would try to explain Andrew Wiles’s proof of Fermat’s Last Theorem to high school students.

As far as "how does one create a moving spacetime" - that is a question physics has yet to answer. It was less than 100 years ago we discovered other galaxies existed, and less than 60 that we discovered that galaxies are moving apart from each other at the same rate of speed depending on the distance. Dark Energy was theorized to solve this expanding universe puzzle, but no one knows what exactly Dark Energy is comprised of and if it even behaves according to the laws of physics we have found thus far or if it is something completely new. There are various theories about an emergent universe that also try and tackle this as well.

Listen to this short 8 minute video from an intellectual hero, and personal friend of mine who is one of the greatest theoretical physicists of our time. His explanation is much more crisp than mine.

Lawrence Krauss - Why is the Universe Expanding?
https://www.youtube.com/watch?v=6FaXQbUvADA

Or if you want a longer lecture
https://www.youtube.com/watch?v=vwzbU0bGOdc
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Posted 4/16/18 , edited 4/16/18

Raakjake wrote:

^^^
Shots fired.

What I'll say is this, do not underestimate the power of the Human consciousness, ego and mind. Things that were once said impossible are a reality now.

Give the science community the same funding you give to murdering civilians over seas I mean the military(We're looking at you America) and enough time I'm sure you will come to realize things that are impossible now, may be possible tomorrow.

The Natural laws we observe here on our Pale Blue Dot may possibly not apply elsewhere in the Universe, we still know so little when it comes to the Universe and its true nature and functionality and we may never know unless we are given eons(hypothetical unit of time, maybe less depending on if/how fast humanity unites as a whole). Yes we can observe laws that are applicable in other parts of our Galaxy or even other galaxy's, but I can easily argue "But you can't confirm it 100% because you haven't been on the other side of the Universe to extract sufficient data to proclaim an absolute Law of the Universe.

IMO.


Yes and no. Your view of science is just misplaced in areas. No one is making absolutes. You can't 100% confirm you are who you say you are because no one can 100% prove anything. Science is a matter of probabilities just like anything else. It's a matter of probably true and probably not true, except in science the standards to achieve "probably true" is quite high. Particle physics uses 5 sigma to ever make an assertion of a new finding. If experiments show results to a 5 sigma confidence level, that means if the results were due to chance and the experiment was repeated 3.5 million times then it would be expected to see the strength of conclusion in the result no more than once. Which is absurdly accurate.

You can argue whatever you want, yet that doesn't make it correct. The natural laws that we have observed thus far will always hold with observations. You can still do Newtonian mechanics to calculate and predict things with remarkable accuracy even though General Relativity has replaced it to explain other phenomena. It's not as if science is saying "well this is now wrong" just because new information arises. Although that is the case sometimes. I will get to the "are the laws of physics universal" part a bit later after going through two examples of observations without directly observing.

No one has observed a black hole - yet we have observed their existence thanks to the behaviors that were long ago predicted like the crazy mass and gravity or even more remarkable what a gravitational wave would look like on the data charts & we detected some waves that matched on the dot.



No one can observe the universe through a third person perspective, yet we can calculate if the Universe itself is open, closed, or flat. In order to prove the flatness of the universe, you would need to travel a long way. And astronomers use the largest possible observation they can make. The cosmic microwave background radiation, the afterglow of the Big Bang, visible in all directions as a red-shifted, fading moment when the universe became transparent about 380,000 years after the Big Bang.

When this radiation was released, the entire universe was approximately 2,700 C. This was the moment when it was cool enough for photons were finally free to roam across the universe. The expansion of the universe stretched these photons out over their 13.8 billion year journey, shifting them down into the microwave spectrum, just 2.7 degrees above absolute zero.

With the most sensitive space-based telescopes they have available, astronomers are able to detect tiny variations in the temperature of this background radiation. And here's the part that blows my mind every time I think about it. These tiny temperature variations correspond to the largest scale structures of the observable universe. A region that was a fraction of a degree warmer become a vast galaxy cluster, hundreds of millions of light-years across.

The cosmic microwave background radiation just gives and gives, and when it comes to figuring out the topology of the universe, it has the answers. If the universe was curved in any way, these temperature variations would appear distorted compared to the actual size that we see these structures today.





But they're not. To best of its ability, ESA's Planck space telescope, can't detect any distortion at all. The universe is flat.

Well, that's not exactly true. According to the best measurements astronomers have ever been able to make, the curvature of the universe falls within a range of error bars that indicates it's flat. Future observations by some super Planck telescope could show a slight curvature, but for now, the best measurements out there say… flat.

Scientists say that the universe is flat, and this means that parallel lines will always remain parallel. 90-degree turns behave as true 90-degree turns, and everything makes sense. But what are the implications for the entire universe? What does this tell us?

Unfortunately, the biggest thing is what it doesn't tell us. Scientists still don't know if the universe is finite or infinite. If we could measure its curvature, we could know that we're in a finite universe, and get a sense of what its actual true size is, out beyond the observable universe science can measure.

Shifting to the possibility of universal laws - when we ask if the laws of physics are mutable, we’re actually asking two separate questions: First, do the equations of quantum mechanics and gravity change over time and space? And second, do the numerical constants that populate those equations vary?

To see the distinction, imagine the whole universe as one big game of basketball. You can tweak certain parameters without changing the game: Raise the hoop a little higher, make the court a little bigger, change the way you score, and it’s still basketball. But if you tell the players to start running bases or kicking field goals, then you’re playing a different game.

Most of the current research into the changeability of physical laws has focused on the numerical constants. Why? It’s the easier question to answer. Physicists can make solid, testable predictions about how variations in numerical constants should affect the results of their experiments. Plus it wouldn’t necessarily blow physics wide open if it turns out that constants do change over time. In fact, some constants have changed: The mass of an electron, for instance, was zero until the Higgs field turned on a tiny sliver of a second after the Big Bang. “We have lots of theories that can accommodate changing constants. All you have to do to account for time-dependent constants is to add some scalar field to the theory that moves very slowly.

A scalar field is any quantity that has a unique value at every point in space-time. The celebrity-du-jour scalar field is the Higgs, but you can also think of less exotic quantities, like temperature, as scalar fields, too. A yet-undiscovered scalar field that changes very slowly could continue to evolve even billions of years after the Big Bang—and with it, the so-called constants of nature could evolve, too.

Luckily, the cosmos has gifted us with some handy windows through which we can peer at the constants as they were in the deep past. One such window is located in the rich uranium deposits of the Oklo region of Gabon, in Central Africa, where, in 1972, workers serendipitously discovered a group of “natural nuclear reactors”—rocks that spontaneously ignited and managed to sustain nuclear reactions for hundreds of thousands of years. The result: A radioactive fossil of what the rules of nature looked like two billion years ago.

The characteristics of that fossil depend on the value of a special number called the fine structure constant, which bundles up a handful of other constants—the speed of light, the charge on an electron, the electric constant, and Planck’s constant—into a single number, about 1/137. It’s what physicists call a “dimensionless” constant, meaning that it’s really just a number: it’s not 1/137 inches, seconds, or coulombs, it’s just plain 1/137. That makes it an ideal place to look for changes in the constants embedded within it, says Steve Lamoreaux, a physicist at Yale University. “If the constants changed in such a way that the electron mass and the electrostatic interaction energies changed in different way, it would show up in the 1/137 unambiguously, independent of measurement system.”

But interpreting that fossil isn’t easy, and over the years researchers studying Oklo have come to apparently conflicting conclusions. For decades, studies of Oklo seemed to show that the fine structure constant was absolutely steady. Then came a study suggesting that it had gotten bigger, and another that it had gotten smaller. In 2006, Lamoreaux (then at Los Alamos National Laboratory) and his colleagues published a fresh analysis that was, they wrote, “consistent with no shift.” But, they pointed out, it was still “model dependent”—that is, they had to make certain assumptions about how the fine structure constant could change.

Using atomic clocks, physicists can search for even tinier changes in the fine structure constant, but they’re limited to looking at present-day variations that happen over just a year or so. Researchers at the National Institute of Standards and Technology in Boulder, Colorado, compared time kept by atomic clocks running on aluminum and mercury to put extremely tight limits on the present-day change in the fine structure constant. Though they can’t say for certain that the fine structure constant isn’t changing, if it is, the variation is tiny: just quadrillionths of a single percent each year.

Today, the best limits on how the constants could be varying over the life of the universe come from observations of distant objects on the sky. That’s because, the farther into space you look, the farther back in time you can see. The Oklo “time machine” stops two billion years ago, but, using light from distant quasars, astronomers have dialed the cosmic time machine 11 billion years back.

Quasars are extremely bright, ancient objects that astronomers believe are probably glowing supermassive black holes. As light from these quasars travels to us, some of it gets absorbed by the gas it travels through along the way. But it doesn’t get absorbed evenly: only very particular wavelengths, or colors, get plucked out. The specific colors that are “deleted” from the spectrum depend on how photons from the quasar light interact with atoms in the gas, and those interactions depend on the fine structure constant. So, by looking at the spectrum of light from distant quasars, astrophysicists can search for changes to the fine structure constant over many billions of years.

“By the time that light has reached us here on Earth, it has collected information regarding several galaxies going back billions of years,” says Tyler Evans, who led some of the most rigorous quasar measurements to date while he was a PhD student at Swinburne University of Technology in Australia. “It is analogous to taking a core sample of ice or the Earth in order to tell how climate was behaving in previous epochs.”

Despite some tantalizing hints, the latest studies all show that changes to the fine structure constant are “consistent with zero.” That doesn’t mean that the fine structure constant absolutely isn’t changing. But if it is, it’s doing so more subtly than these experiments can detect, and that seems unlikely, says Carroll. “It’s hard to squeeze a theory into the little daylight between not changing at all, and not changing enough that we can see it.”

Astrophysicists are also looking for changes to G, the gravitational constant, which dials in the strength of gravity. In 1937, Paul Dirac, one of the pioneers of quantum mechanics, offered up the hypothesis that gravity gets weaker as the universe ages. Though the idea didn’t stick, physicists kept looking for changes in G, and today some exotic alternative theories of gravity embrace a shifting gravitational constant. While lab experiments here on Earth have returned confusing results, studies off Earth suggest that G isn’t changing much, if it all. Most recently, radio astronomers scoured 21 years of precise timing data from an unusually bright, stable pulsar to see if they could trace any changes in its regular “heartbeat” of radio emission to changes in the gravitational constant. The result—nothing.

But back to the second, tougher half of our original question: Could the laws of physics themselves, and not just the constants sewn into them, be changing? “That’s much harder to say,” says Carroll, who points out that there are different degrees of disruption to consider. If the rules of some “sub-theory” of quantum mechanics, like quantum electrodynamics, turned out to be fluid, maybe existing theory could accommodate that. But if the laws of quantum mechanics itself are in flux, says Carroll, “That would be very bizarre.” No theory predicts how or why such a change might happen; there is simply no framework from which to investigate the question.

As far as we can tell, the universe seems to be playing fair. But physicists will keep scouring the rulebook, looking for clues that the rules of the game could be changing at a level we haven’t yet perceived.
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Posted 4/16/18 , edited 4/17/18
Someone? Yes. Not me, of course. Some years ago on CR, there was an in-depth discussion about black holes. It was really, really interesting. Several purported physicists were hosting the conversation. For the life of me, though, I cannot remember their CR names. I wish that I had saved screenshots for reference.
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