Time, Time Travel, and Closed Timelike Curves

[marduk]

You can get a cheap UPS from amazon for about $60. That won’t stop your computer from just crashing, though.

To fix that, you need to unplug your PC and go to the apple store.

 

[Randall]

You can get a cheap UPS from amazon for about $60. That won’t stop your computer from just crashing, though. To fix that, you need to unplug your PC and go to the apple store.

Very funny. I used to sell Apple and a variety of other brands, and of the new units sold, Apple returns were among the most frequent. However Apple laptops have excellent battery life and the workmanship is superb. However I can change the battery on my Acer in literally 30 seconds without any tools, buy extra ones cheap, and the whole thing is about a third the cost. I'm still running Win 7 and it's been rock solid.

Vintage Mac Crash Screens

More Recently

OK no more Mac vs. PC here Sorry but I couldn't resist. ​

​

 

[DROBNJAK]

That’s where the quantum Zeno Effect — a.k.a. Turing’s Paradox — comes in. Taking its name from Zeno’s arrow paradox (a moving arrow can’t actually be seen moving in any single instant, which means it’s not really moving at all), this idea basically states that if you never stop observing a particle that undergoes decay, then that particle will never decay. If that particle never decays, you’ve basically stopped it from doing anything. You’ve stopped time.

Quantum Zeno effect. The quantum Zeno effect (also known as the Turing paradox) is a feature of quantum mechanical systems allowing a particle's time evolution to be arrested by measuring it frequently enough with respect to some chosen measurement setting.

Experiments and discussion
Experimentally, strong suppression of the evolution of a quantum system due to environmental coupling has been observed in a number of microscopic systems.

In 1989, David J. Wineland and his group at NIST[33] observed the quantum Zeno effect for a two-level atomic system that was interrogated during its evolution. Approximately 5000 9Be+ ions were stored in a cylindrical Penning trap and laser cooled to below 250 mK. A resonant RF pulse was applied which, if applied alone, would cause the entire ground state population to migrate into an excited state. After the pulse was applied, the ions were monitored for photons emitted due to relaxation. The ion trap was then regularly "measured" by applying a sequence of ultraviolet pulses, during the RF pulse. As expected, the ultraviolet pulses suppressed the evolution of the system into the excited state. The results were in good agreement with theoretical models. A recent review describes subsequent work in this area.[34]

In 2001, Mark G. Raizen and his group at the University of Texas at Austin observed the quantum Zeno effect for an unstable quantum system,[35] as originally proposed by Sudarshan and Misra.[1] They also observed an anti-Zeno effect. Ultracold sodium atoms were trapped in an accelerating optical lattice and the loss due to tunneling was measured. The evolution was interrupted by reducing the acceleration, thereby stopping quantum tunneling. The group observed suppression or enhancement of the decay rate, depending on the regime of measurement.

In 2015, Mukund Vengalattore and his group at Cornell University demonstrated a quantum Zeno effect as the modulation of the rate of quantum tunnelling in an ultra-cold lattice gas by the intensity of light used to image the atoms.[36]

The Quantum Zeno Effect is used in commercial atomic magnetometers and naturally by birds' magnetic compass sensory mechanism (magnetoreception).[37]

It is still an open question how closely one can approach the limit of an infinite number of interrogations due to the Heisenberg uncertainty involved in shorter measurement times. It has been shown, however, that measurements performed at a finite frequency can yield arbitrarily strong Zeno effects.[38] In 2006, Streed et al. at MIT observed the dependence of the Zeno effect on measurement pulse characteristics.[39]

The interpretation of experiments in terms of the "Zeno effect" helps describe the origin of a phenomenon. Nevertheless, such an interpretation does not bring any principally new features not described with the Schrödinger equation of the quantum system.[40][41]

Even more, the detailed description of experiments with the "Zeno effect", especially at the limit of high frequency of measurements (high efficiency of suppression of transition, or high reflectivity of a ridged mirror) usually do not behave as expected for an idealized measurement.[17]

It was shown that the Quantum Zeno effect persists in the many-worlds and relative states interpretations of quantum mechanics.[42]
Quantum Zeno effect - Wikipedia

'Zeno effect' verified: Atoms won't move while you watch | Cornell Chronicle


It's not just theoretical. The Cornell experiment is just the latest in a series of experiments since then confirming that the quantum Zeno effect really happens. (There's also an "Anti-Zeno Effect," whereby staring at the metaphorical quantum pot brings it to a boil more quickly -- also experimentally confirmed.)
Quantum 'Weeping Angel' Effect Freezes Atoms In Place

You know @mike, I am here to certify that you are smart. I was lifting every rock under the Sun to try to match trends in UFO incident witness testimonies, and is this really interesting angle.

UFO witness trends suggest such a weird things like massive EM fields, inertia cancellation and time deletion without space curving, that one hits a brick wall even when he digs into deepest physics.

But, if I am not understanding this wrongly, quantum Zeno effect practically stops QM effects inside material when one radiates material with precise EM frequencies?

 

[Thomas R Morrison]

you understand that nobody's saying that the Earth is expanding at an accelerating rate, but that an acute geometric angle between space and time generates an acceleration field, right?

That's the whole point. It's an analogy, meaning analogous to acceleration, just like curved space is an analogy.

I never said that it’s an analogy: you’re saying that. I’m disagreeing. Gravity is an acceleration field. Spacetime actually appears to be curved. I have yet to see a model that can explain our physical observations without a physical curvature of spacetime. One might be presented someday, but that hasn’t happened yet, so I’m sticking with the “spacetime is literally curved” explanation until something better comes along, if something better ever comes along. That how science works – we go with what works until we come up with a model that describes reality better. I have no problem with that.

Absolutely. You come across as exceedingly bright, that's why this is such a curiosity. I see where the disconnect is with you, but I can't seem to figure out how to bridge it.

I don’t see a disconnect – I simply don’t see how you can assert that you’re right, when all of the observations are 100% consistent with a physically curved spacetime. I’m perfectly willing to accept that one day we may have an explanation that involves quantum forces acting in a flat spacetime, which only makes it look like spacetime is curved. But until we actually have a theory that can do that, I’m going with the theory that we have, which works spectacularly well.

Ironic that you should mention the Greeks because they are the ones that came up the theorems for Euclidean geometry which can be worked out entirely conceptually.

Riemannian geometry has been entirely worked out conceptually too. And it explains gravity, which Euclidean geometry can’t do, or at least hasn’t done yet. So I think it’s ironic that you think it’s ironic.

Your thought experiments don't prove that space cannot be curved.

That is a proclamation, not an explanation that addresses the logic used in the thought experiments.

Nope, it’s a statement of fact. Your thought model goes like this: “if we subtract the curvature of spacetime from our observations, then spacetime appears to be flat, because we can draw a straight line between two points.”

That’s not a rational argument. That’s like saying: “if we subtract the influence of gravity, then when I throw a ball upward, it won’t fall back down. Therefore there’s no such thing as gravity.” That’s crazy. It proves nothing.

"from a God's eye view?" Please tell me that you're joking.

It's a figure of speech, like writing from an omniscient point of view. It doesn't literally make the author God. It is a point of view.

Yes, it’s a point of view – God’s point of view:

“God's eye view is a name for a point of view where the speaker or writer assumes they have knowledge only God would have.”
God's eye view - Simple English Wikipedia, the free encyclopedia

I don’t have the benefit of knowledge that only God would have. All I have are my sense perceptions and the scientific method. And so far that’s worked out pretty well for me.

how it is that you can't imagine a simple cubic volume of space inside of which objects are placed and see that formulas can be mapped onto those objects in a way that causes them to behave exactly like they are predicted to behave in the real world, without having to distort any of the space, and in addition to that, you could draw a straight line between any two objects in that space. You should be able to plainly see that no curved space is necessary to create a system that does everything the math you're referring to predicts. Therefore there is no reason to think real life space is curved either. Stuff just behaves as if it is curved due to the forces that are imparted on them by nature.

No living human being has ever been able to make that model work.

If you can make that model work, then explain to me how time is slower on the surface of the Earth, without invoking a curved spacetime. I’ve asked you this before and you ignored the question. Why? I’ll tell you why: because no cogent model of reality has ever been forwarded which explains gravitational time dilation within the context of Euclidean space. That’s why.

I’m willing to accept that one day, somebody might figure that out, and provide an equation that explains it to high precision, just as GR does now.

But right now, GR is the only theory that explains gravitational time dilation, and gravitational lensing, and gravitational waves, and the precession of the perihelion of Mercury, and on and on. And the fact that it actually predicted all of that stuff, which has now been confirmed to within the observational precision of our modern day era, a century later, is plenty of justification for taking it seriously, and literally, imo.

 

[Randall]

I don’t see a disconnect – I simply don’t see how you can assert that you’re right, when all of the observations are 100% consistent with a physically curved spacetime.

Maybe this will help. In the above statement the issue is framed in terms of me being right or wrong compared to observations that are 100% consistent with a physically curved spacetime. That is not the issue. I'm not disputing the accuracy of the methodology. I'm disputing the leap in logic that says because the methodology accurately predicts how things behave, it must also mean that it is also how things actually are.

Because acceleration is equivalent to gravity doesn't mean it is gravity. Because things in space behave is if space is curved doesn't mean space is curved. Because an AI passes the Turing test doesn't mean it's human. I don't know what else to do other than draw a picture, so it's probably best to let this one rest for the time being.

 

[Thomas R Morrison]

Maybe this will help. In the above statement the issue is framed in terms of me being right or wrong compared to observations that are 100% consistent with a physically curved spacetime. That is not the issue. I'm not disputing the accuracy of the methodology. I'm disputing the leap in logic that says because the methodology accurately predicts how things behave, it must also mean that it is also how things actually are.

Because acceleration is equivalent to gravity doesn't mean it is gravity. Because things in space behave is if space is curved doesn't mean space is curved. Because an AI passes the Turing test doesn't mean it's human. I don't know what else to do other than draw a picture, so it's probably best to let this one rest for the time being.

This a philosophy of science issue. Ultimately every physical observation can be questioned: "sure it looks like X is happening, but it could be interpreted instead as an illusion produced by Y" But I'm a pragmatist. From my point of view the onus is on the challenger to mathematically demonstrate a self-consistent theory that shows that X actually can be an illusion produced by Y. Otherwise, the challenge is irrelevant.

If you can make a drawing that explains gravitational time dilation without curved spacetime, I'd like to see it.

 

[Randall]

This a philosophy of science issue.

Yes.

Ultimately every physical observation can be questioned: "sure it looks like X is happening, but it could be interpreted instead as an illusion produced by Y" But I'm a pragmatist.

The answers to philosophical questions can have practical applications, and we're not dealing with an illusion. We're dealing with an analogy.

From my point of view the onus is on the challenger to mathematically demonstrate a self-consistent theory that shows that X actually can be an illusion produced by Y. Otherwise,the challenge is irrelevant.

That is not a logically coherent position to take because while the math may be internally consistent, it doesn't mean that reality = math.

If you can make a drawing that explains gravitational time dilation without curved spacetime, I'd like to see it.

That method cannot prove or disprove the point I'm making because it's making a false assumption about the initial premise. I'm not saying that the algorithms based on the curved spacetime analogy should not be used to calculate the behavior of objects in space. One more try:

I'm saying that in theory we should be able to create a virtual 3D construct with nothing but x,y,z resulting in a simple single unit of volumetric space e.g. a cubic parsec, and then map the same algorithms you're talking about directly onto any objects in it so that with the addition of t they behave exactly the way they would in real space. Therefore because such a situation is theoretically entirely possible, there's insufficient reason to jump to the conclusion that real space is anything other than a uniform 3D construct, or that the behavior of the objects in space isn't due to forces imparted on them by some means that we aren't clear about.

In reality, that also seems to be the case. We still have no idea how gravity is imparted onto matter. We just know it is. It's not because "space is curved - therefore gravity". It's because gravity - therefore we can calculate how things in space behave by thinking of gravity as affecting space in a way analogous to it being curved.

In other words, this could all be a big Matrix like simulation where some vastly powerful system computes the path light takes around a star, without needing to "distort space" at all. At t1 photon will be at x1,y1,z1, because ( insert formula here ) says so , then at t2 photon will be at x2,y2,z2, because ( insert formula here ) says so , and so on, so that you get the same exact behavior we see. No curved space required. This makes perfect sense and in fact would require that space be uniform in order to calculate accurate x,y,z, coordinates over time.

The alternative is that at t1 the photon will be here, and at t2 we'll change some subset of x,y,z, in such a way that the photon will just magically change direction all by itself somehow like a marble passing a bowling ball on a big rubber sheet. That's a tail wagging the dog approach.

Is It Really So Hard To Believe?

 

[withoutlimits09]

I was listening to an old Art Bell episode with "Doctor" Fred Bell, he claimed he built his own time machine that allowed him to go a few milliseconds into the future, since the future is not actual, but rather only potential, he claims he was in a dark void of "nothing."

I personally think the guy is totally full of crap. His doctorate is in "natural healing" and I can't find much else about his education, but he claims to have had his hand in virtually every aspect of our space program. He is a good story teller though, and he often talks about "time travel," so if that is your thing, you can probably look into his "research."

 

[Thomas R Morrison]

Yes. The answers to philosophical questions can have practical applications, and we're not dealing with an illusion. We're dealing with an analogy.

I kinda feel like a hypocrite debating this with you, because I’m perfectly aware that we may (and probably will, eventually) develop a completely new model of gravitation that makes the current model look quaint and effective, but misguided, much as we see Newtonian dynamics now.

One day, perhaps even one day fairly soon, we’ll probably have a quantum theory of gravity, for example.

And there’s another idea that has haunted me ever since I studied Daniel Fry’s books – he could be right to claim that it’s not spacetime that’s curved, but rather the laws of physics themselves. He never elucidated that idea satisfactorily, but I’m fascinated with his suggestion that all of the different physics equations that we employ today – QCD and QFT at the microscopic scale, Newtonian dynamics at the terrestrial scale, and cosmological dynamics at the universal scale (which is currently plagued by the mysteries of dark matter and dark energy), represent the same laws of physics operating at three highly disparate scales upon a single circular curvature, akin to how the Lorentz transform defines a unit circle in the special theory of relativity. It works for velocity and time dilation, and he provided a model to illustrate how it works for mass-energy and velocity, but how it could work for the nuclear strong force or gravitation is beyond me.

It’s a notion that I’ve never heard before or since. But there’s something so tantalizing and elegant about it – I just can’t my escape my fascination with it. I wish I knew how to go about modeling such a thing on paper.

I was listening to an old Art Bell episode with "Doctor" Fred Bell, he claimed he built his own time machine that allowed him to go a few milliseconds into the future, since the future is not actual, but rather only potential, he claims he was in a dark void of "nothing."

I personally think the guy is totally full of crap. His doctorate is in "natural healing" and I can't find much else about his education, but he claims to have had his hand in virtually every aspect of our space program. He is a good story teller though, and he often talks about "time travel," so if that is your thing, you can probably look into his "research."

Yeah I heard that interview – it was fun, but man, that’s guy’s a nutter. Even if he found himself surrounded by darkness while standing in the middle of some crazy contraption, why the hell would he conclude that he was in the future and it was dark because it didn’t exist yet? Seems more likely that he’d just fried his brain with electromagnetic field energy or something. But frankly I think that he was just a crazy guy who loved to tell stories.

Has anyone ever verified that he actually worked on any real scientific project? I tend to imagine that he’s just some wild man from the 60’s who probably lives in his mother’s garage surrounded by weird contraptions made from spare parts that he found in the trash, which don’t do anything but inspire his already overactive imagination.

 

[Randall]

I kinda feel like a hypocrite debating this with you, because I’m perfectly aware that we may (and probably will, eventually) develop a completely new model of gravitation that makes the current model look quaint and effective, but misguided, much as we see Newtonian dynamics now.

Actually, I'm somewhat relieved to hear that you were simply debating, and it seems more clear now that when you use the phrase "model of gravitation" as equivalent to ( insert whatever formula here ), I think that might be the crux of our difference. It's not one of facts but of perspective. One can certainly think of a formula as a model. From that perspective, you are right on the money with every point you've made. However I look at the word "model" in a different context. Rather than as a formula, I see gravity one of the "fundamental forces of nature", and formulas as ways of predicting how those forces make things behave, from apples falling off trees, to photons passing by massive objects in space. In this situation, neither of us will ever be successful in convincing the other that their model is in error, because both are correct. Without getting that tidbit, from the perspective of a person arguing formulas, someone who agrees that the formulas work, but doesn't agree that they reflect reality, would seem to be fooling themselves about the level of their comprehension.

One day, perhaps even one day fairly soon, we’ll probably have a quantum theory of gravity, for example.

Quantum theory is another very useful way of looking at things, but ultimately I think it will become "quaint" ( as you say ). At the core it's like digital versus analog. I think that whatever imparts the fundamental forces of nature simply does it on whatever scale is appropriate and that it's not necessary to break it down into quanta. This is why I very strongly suspect that we'll never find a graviton or the real Higgs Boson, or any actual dark matter. It's not a thing ( like a quanta of "stuff" with property x or y ) , but more like a field that is simply associated with some volume of space at some set of coordinates. String theory is closer to that idea. I wrote a thing on that some days ago, but nobody commented. Such are the ramblings of my mind, that fortunately just putting it out there is satisfaction enough.

 

[withoutlimits09]

I tried to google some of the professors he said he worked under but could not find any, namely, "Dr. Katz" at the University of Michigan.

Dr. Fred Bell & Pyradyne

Bell claims he worked on all of the lunar modulars, yet, I can't find a single photo of him near one, or even at NASA.

 

[Thomas R Morrison]

This is why I very strongly suspect that we'll never find a graviton or the real Higgs Boson, or any actual dark matter. It's not a thing ( like a quanta of "stuff" with property x or y ) , but more like a field that is simply associated with some volume of space at some set of coordinates.

Statements like this show that you have good instincts, but you have to study physics more deeply to make better use of them: you just very successfully described the central concept of quantum field theory (QFT). In QFT , the prevailing model of particle physics today, the universe is comprised of several overlapping and intersecting quantum fields, and the excitations in those fields (sort of like ripples in the ocean) are what we call "particles." They can be like standing waves, hanging out in one place, or they can travel like a sound wave from one position in the field to another. And I also favor dynamical explanations of dark matter and dark energy, over particle explanations - if they were associated with particles then I think we would've seen them by now. But I think you're wrong about the Higgs boson - there's a very high sigma for that signal now that fits the Standard Model quite well (in fact we wouldn't have found it at all if the Standard Model hadn't provided the correct parameters in the first place). The graviton is trickier - it's just weird to think of a ripple in spacetime as a particle. But spacetime is just a field, so a graviton interpretation makes sense within the context of QFT if we interpret spacetime as just another form of quantum field.

But the real reason I wanted to post in this thread is this: I've been working on a new interpretation of the special theory of relativity, and I've found that it's very elegant and illustrative to treat space as a dimension of time, so that all units are in time units. We're used to seeing this in the field of astronomy, where we measure spatial separation in units of time such as "one light-year" (1LY), but it's a bit less common to see it used in terms of speed, such as .25LY/year, aka .25C. In this system of units which are known as "natural units," the physics is very beautiful though - for example, the Lorentz transform at the heart of the special theory of relativity becomes the equation of a circle (as I illustrated with the graphs on page one of this thread).

The laws of physics become very simple and elegant when everything including space and velocity are measured exclusively in units of time. I keep thinking that would annoy you, since you seem to regard space as physical while rejecting the notion of time as a dimension - but the laws of physics reach maximum symmetry when all dimensions are measured in units of time =)