One could imagine branches in acritical tree of thousands of Feynman diagrams set up for one direction's motion reversing course perfectly. Nature of that sort of hieroglyph. But given the affect admitted for entropy and/ or quantum flipping (they seem correlated in essence) at each conceptual iteration, the road backwards would quickly breakdown. Erode.
What bothers me in quantum anything is the problem of testing. The failure of being able to follow a small "particle" may be more a problem with the gnomen we have to use. With standard theory an artifact from that limit.
(& the descriptive modes of scattering seems to sweep the possible mechanism at work under easy statistics... I like to consider, 2 D simile, so to speak, spinning rotor on a frictionless surface with a number of paddle/arms at a certain rpms being swarmed by a stream of BBs, how does that look with 2, 3 , 4 "arms", with hooked, etc. shape...how does that "scatter" the "particles"...
just a thought analogy for a bit of speculative meditation...)
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@M. J. Shepley: The idea of a mechanism, versus what I've heard about quantum effects. It's the randomness. How there will be a scattering that can be talked about very precisely in terms of probabilities: some in this direction, more in that direction, less in the other direction... and yet, there doesn't seem to any underlying complex regularity like in your model. That seems to me to be the mystery: particles decay at a very precise rate, and in the macroscopic world, that would seem to indicate some kind of timing mechanism, a bond weakening, or pressure building up like in the kernels of popcorn in the popper. And yet these so-called particles seem not to have the kind of internal structure that would make "pressure building up" at all meaningful. And yet, they show this random behavior, with precisely measurable rates... Something to meditate on indeed.
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Eric here, eighty nine years young and glad to have read and resonated with both Alan Watts (b. 1915): “the basic mind which knows reality rather than ideas about it, does not know the future, lives completely in the present,” and Rumi (b. 1207): “Somewhere in this town sits a calm, intelligent man, who doesn’t know what he’s about to do,” they among many inviting us to realize the only time is “now,” the only place “here.” Saying, “Tomorrow I’ll meet you there” speaks of a time that isn’t and a place which always reveals itself as “here” when we arrive. Looking toward a non-existent future is looking away from
here-now, only the feeling-of-being constant and constantly changing.....rather than feeling “we are helplessly trapped in the flow of time” and though often aching with sorrow that we are destroying this beautiful Garden we’ve be given I am wholly grateful to be, here, now.....
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@Eric Leber: I used to work through the thought experiment that if I were really in the real "now", the right-now now, it would just be that I couldn't experience a musical phrase, because the first note would be gone as the second one came in... but I wouldn't even experience a musical note, because the pulse would either be on or off, but I wouldn't be counting the rate of pulsation. Now I'm pretty sure that most of that is taken care of in the nervous system before it reaches the conscious mind, the mind is presented with a sonorous B flat, not with a complex series of pulses -- and maybe the mind is presented with an ascending scale, rather than a series of separate notes. It's all pretty amazing.
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@Eric Leber
What a wonderful comment. It's why I read the NYT.
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This idea of time reversing backwards has always created a paradox for me. “Time” for me is merely an expression of “duration” or “duration of existence” and it moves forward in a straight line. If (i) I’m sitting in a room with a friend and there is an encyclopedia opened to the page about Napoleon, (ii) I climb into my time machine and travel back to 1769 and kill the baby Napoleon in his crib, (iii) what happens to the page my friend is holding in his hand? Does it disappear? But how, if it never was? But it existed before I climbed into the “Wayback” machine. See, this is a mind-bending paradox, suitable only for stoners to contemplate. People, myself included, often ask what happened “before” the Big Bang. I’m told it is the wrong question because time (duration) did not exist before the Big Bang. In fact, there was no “before” prior to the Big Bang. Nothing existed, not even existence itself! Geez. Then, to quote a line from Talking Heads: “How did I get here?” Then to quote another line I heard last week on Star Trek Discovery: “The universe has no obligation to be logical”.
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@styleman: I'm glad to hear they said that on Star Treck: people get caught up in logic, and forget that it takes some careful selection to find things that fit into it. I remember a scene from an Italian movie, I think it was "Red Desert", ages ago. A kid asks his mother "What is one plus one?" and she of course says "Two", and he silently takes an eye-dropper and drips two drops of water into his palm, getting one big drop.
It would seem that in the case of Napoleon, you could be sure that if you went back in your time machine, whatever baby you killed wouldn't be the one that grew up to be Napoleon, because you would know the future and know that something we called the Napoleonic Wars was going to happen -- (Or maybe there was never a Napoleon, maybe it was like Banksy (maybe), and different Corsicans took turns being "Napoleon" wherever appropriate.)
Sort of like how, in the spacial dimensions, it doesn't make sense to ask your buddy holding up the other end of the ladder "suppose one of us wasn't here?" -- because of course, as it happens, you are both there at your respective ends of the ladder. If that makes sense.
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Perhaps you cannot reverse time on just the scrabbled egg alone while the rest of time marches forward. In order to bring the egg back in time to its forner state you may have to reverse time in whole for everything.
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@Brian: That's how I always do it. Nobody even notices.
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Ah.. so few folks study optics. Time is changing all the time in optics. The speed of light, c, changes when light goes from a vacuum (c) thru materials. Like air. Like glass. The ratio.. read ratio of the speed of light in a vacuum to the speed of light going thru glass, is the Refractive Index. RI.
Light, goes slower through a lens.
Why ?
So, if you want to play with time, develop devices that change, oscillate, increase/decrease the Refractive Index...
My 1971 Science Fair Project in WV - was about linked time scales -2c: -1c: 0c: +1c +2c. I called particles going faster than tacyhons - that term may have been out then, and particles going slower than 0, ie back in time: Tardons.
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Well, it didn't "reverse time" in the sense that time went backwards. If the experiment took half an hour, then the final state occurred half an hour after the initial state. There was nothing like "Inside the test-tube, it was 11:15 again, and the experiment hadn't happened yet." It was "After the experiment, the state inside the test-tube was exactly like it had been when we started." (Except, apparently, there was no test-tube, there was a virtual, mathematical test-tube that reverted to its original state.) I'm not knocking it, I'm sure it was an impressive result, and this is only the beginning, but, in terms of saying what happened, it wasn't about reversing time. At least, not in any ordinary sense.
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Stephen Hawking looked at black holes, and today's scientists see to produce backward time travel. All of this at a time when the only species capable of even contemplating such things teeters on the brink of its own destruction. These great minds need to focus firstly on what causes humans to act so irrationally toward on another; and, when that's figured out, turn their attention to these frivolous ideas.
In the near future, we will program the human mind in the computer based on a "survival" algorithm, which will provide irrefutable proof as to how we trick the mind with our ridiculous beliefs about what is supposed to survive - producing minds programmed de facto for destruction. These minds see the survival of a particular belief as more important than the survival of us all. When we understand all this, we will begin the long trek back to reason and sanity.
See RevolutionOfReason.com
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I wonder how Bill Bryson would have addressed this topic in "A Short History of Nearly Everything?"
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There's no such thing as time going backwards. It's a fallacy of language, and not even part of science fiction or fantasy. If events proceed in what seems to be the reverse of their usual direction, that occurs in regular forward-moving time. The nature and definition of time is such that it only proceeds in one direction.
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@Paul O
Intuitively, Paul O is correct. But by the same token, time should not speed up or slow down depending on how fast an object is moving, yet everyone says it does. I've always found that suspect: the movement of particles by which one measures time may change speed, but is that the same thing as saying time is changing speed? And if time does change speed, isn't that a measurement that exists only relative to time that is constant in speed?
@ss
Good questions, ss. My feeling is that time has more to do with psychological factors and our experience of time - than with what might be measured objectively (if there is such a thing.) If time is our experiencing of it (and how can it not be?) then its measurement is really a matter of its granularity in our viewing of the world. Time seems to be [our experience of] the changes in the world that we perceive.
@Paul O. According to principals while you can never go faster than the speed of light; as you approach the speed of light time slows. If you could go faster than light in theory, time would begin to go backward.
It's amazing reading these comments how so many are along the lines of "I don't understand this, therefore, it's absurd." And so many that are, bluntly, absurd.
An intelligent person recognizes the limitations of her/her intelligence and steps aside in dialogue, and learns from those smarter than most of us.
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@Jus' Me, NYT: Well, it's not necessarily just intelligence, it's also usually quite a few years of diligent study, and communicating with others in the field, and in this case access to some specialized equipment. But yes, there is some truth to what you say...
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Unfortunately, more quantum misunderstanding. Heisenberg never said anything about "uncertainty". A better translation is "undefinability" (Except for a comment in his footnote). More significantly, talking about probability of state in relation to an analog function is nonsense. It is like saying what is the probability someone will have a height of 5 ft, 6.00345 inches? Right answer: close to zero. The tighter you define the range the lower the probability. Probability is only meaningful in relation to a range not a value. Understand this simple concept and much of the quantum weirdness goes away. It is not peculiar to quantum states, in fact it is widespread in the non-quantum world in which we live. This is all that Heisenberg said, yet he is credited with discovering something weird or magic. Incidentally, neither Schrodinger nor Einstein accepted these ideas that are widespread today. The problem is, if you don't go along with it you won't get published or funded.
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I have always understood the arrow of time as being the result of entropy. This is the first time I have seen it associated with the uncertainty principle. I'll have to think about that.
But a question: Yes the qubits returned to their original states after some passage of time. But if I put a child on a tricycle on a circular track and give her a push or two, I'm guessing she will return to her original state after once around the track -- just a bit older. What am I missing here?
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@J Fogarty Here's how I think of it:
"Entropy" is the "arrow of time". "Entropy" is the "technical term", ie, the label for what thermodynamic equations describe. "Arrow of time" is a metaphor, devised to "interpret" the fact that only the "forward" solutions match observation and experiment.
Physicists try to explain the equations by devising metaphors, such as "arrow of time."
Metaphors imply consequences. "Wave function collapse" is an example of how pushing the implications leads to nonsense. There is no "collapse". A wave function is not like a stone wall. The experiment yields a number. Running the experiment a picosecond earlier or later it would have yielded a different number. That's all. Nothng "collapses".
When "quarks" were discovered, the phsyicists knew they needed labels for the entities described in their equations. They tried to devise nonsense labels so as to prevent people from misunderstanding what these entities really are. Actually, we don't know what they "really" are. We know only that experiments devised to test the validity of the equations agree with the calculated numbers.
Footnote: Many years ago, I read a story in which "coherence" at the subatomic level was posited as essential for time travel. Somebody Knew Something! Maybe a time-traveller, sowing the seeds of time-travel technology in our era, so that he could time-travel in order to sow the seeds of time-travel technology in our eera, so that he could time-travel....?
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@J Fogarty: Good question (ie, I was thinking the same thing) If you define a beginning state, then say, "Then we'll let the particle move a certain distance, then return it to the beginning state" this doesn't seem to be at all interesting. I'm thinking that this project involved some quantum aspect, like one of those totally unpredictable things like the exact time of a particle decay, and then was able to somehow run it backwards (only without just rewinding the film) and return to the original state in spite of the unpredictability. (If that even means anything.) I'll have to re-read this a few times and see if I can get something more out of it.
Extraordinary claims require extraordinary proof.
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Fascinating and frustrating an article. Words used to describe quantum events is the 21st-century equivalent of Syphilis pushing the rock up the mountain, utterly futile. Mathematics best approaches the truth of this strange world. What was done was a simulation using a quantum device. No "thing" went back in time, only a model of a thing going backward in time was achieved. I look forward to more from the author about this strange world. Please tells us about those Quantum computers; all 7 qubits of processing power.
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@Richard Kinne
Returning qubits to their original state is maybe oxymoronic too. What could an uncoherred original state have been? Dennis Overby means something important no doubt but the language doesn't quite work. Anyway the original state the qubits returned to surely hadn't reversed the age of their containing computer or laboratory or universe one wit.
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@Richard Kinne It is Sisyphus who in Hades of the ancient Greeks continually rolled a stone uphill, only to have it roll to the bottom in an endless cycle. Syphilis has no known connection to the aforementioned legendary Greek. :-)
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@Johanne T.
Syphilis would surely be a reversal in Sisyphus' life.
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Time is a human construct--I agree with that.
Time was "constructed" when humans realized they died, and had to have some means of deciding what to do between now and, well, let's call it "then."
Someone here is going to correct me, because my memory has a "use by" date that may be getting close, but here goes: I believe I've read that the Greeks called Chronos the father of death, since it's time that separates birth--creation of life--from death, end of life. Without time, we wouldn't have to die?
Anyhow, I agree with SCPro, below--I don't understand this, but I don't believe anyone else does, either.
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GREAT comments section!
If time is (currently) one of the impenetrable mysteries to our minds, perhaps the limitation is with our minds. As "superintelligence" inevitably develops, perhaps a measure of its super-ness will be that such mysteries are easily solved. Then the bigger challenge to the superintelligence will be dumbing down the explanations so that we of limited minds can understand it.
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Beyond my understanding. Appears this study was paid for by a corporation, not a federal grant. Appreciate basic science without practical or economic payoff directly obvious.
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This is extremely fascinating. Although we (ultimately) don't know where it will lead, I think all involved should continue their research. As Einstein was quoted, it's "spooky action at a distance".
Typically well stated by Albert.
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So far, switching devices of computer are developing. First, switching device of ENIAC is relay. And then, the computer consists of digits 0-1 by electromagnets. Next switching device became vacuum tube. The circuits of multivibrator(including vacuum tubes) made the computer. Nowadays transistors( MOS transistor) have replaced vacuum tubes. I mean, nanotechnology era has come because semiconductor’s switching devices are very speedy and small, and seldom break down. But at last, quantum computer appears. Moreover, quantum switch ( qubit ) is speedy and small. Cost of quantum switch is problematic to compare with MOS transistor. But I guess the future of computers are quantum computers because of their speed.
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@Toshihiro Hirai: I wonder, though, if it's just greatly increased speed for the same basic operations, or if there will be some whole new kinds of logic available because of the circuits being in various states simultaneously. Still waiting to understand what this is about.
So far, switching devices of computer are developing. First, switching device of ENIAC is relay. And then, the computer consists of digits 0-1 by electromagnets. Next switching device became vacuum tube. The circuits of multivibrator(including vacuum tubes) made the computer. Nowadays transistors( MOS transistor) have replaced vacuum tubes. I mean, nanotechnology era has come because semiconductor’s switching devices are very speedy and small, and seldom break down. But at last, quantum computer appears. Moreover, quantum switch ( qubit ) is speedy and small. Cost of quantum switch is problematic to compare with MOS transistor. But I guess the future of computers are quantum computers because of their speed.
Going backwards with an imaginary atom is not science. It is a thought experiment at best.
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Once something is imagined it exists.
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Non-physicist here. As I understand it, the Heisenberg uncertainty principle states it’s impossible to precisely know both the position and momentum of a particle. It’s an inherent property of matter based on its wavelike properties. Given that momentum has its own inherent time component, the uncertainty principle implies a certain smear effect for time itself at the quantum level.
It’s also seems circular to me to use entropy in any way as an explanation for time. Entropy is a concept of change in state (towards more disorder) over TIME. The same goes for speed. It only exists if there is time.
But, curiously, at the speed of light time slows to zero. Photons exist in our universe. They are emitted from my computer screen and travel all about. Some are absorbed by my retina and disappear, providing for vision. But they have no mass and time never passes for them.
It seems time must be an inherent property of matter. If it exists, it must last for matter to have meaning. It’s the essential miracle that allows all existence.
The second miracle, at least the one allowing human existence, is gestation of a new life in the wombs of our mothers. And that endless series of mothers seems to go back all the way to inanimate pond scum on a primordial earth. We are essentially born of matter that had to exist and last over time. But it’s our mothers that give our lives the chance to have meaning.
Thanks, mom, and hppy Mother’s Day.
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I'm OK with all this if and only IF it brings us closer to extinction...but of course, it will since everything else does.....
It seems to me that there must be entities that exist out of time. They are always just there and always will be. They weren't created, they never changed. Thiests might point to God who, among His other properties, could not have been created by Something Else.. For cosmologists these uncreated basics are the forces that made and continue to make the universe or universes. If then we could understand the nature of the non-time in which these entities exist, we could compare it to what we know about conventional time and find a common factor that allows time to flow or not. This isn't going to be easy. Finding something that just "is" would be along the lines of a fish discovering water. And it will take more than quantum computing. In the end, we might discover that the thing we are looking for is the one thing that cannot be discovered or described. But maybe we'd get lucky.
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I think this will lead to the fulfillment of man’s dream of going back and forth in time, leading to perfection in our lives.
An interesting article, after reading it, the idea of States of a Entangled particle returning to it's original after excited, is not really becoming younger insofar as entanglement shows that it was never older only different.
Returning it to it's original state makes more sense.
The Time-space factor only points to the variance of the process.
Just a thought.
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I don't claim to understand all this, but I'm not convinced anyone else does, either. Maybe the concept of a "point in time" is actually unrelated to the flow of time. Returning to a past point in time might require manipulating the entire universe to a previous state. And even that may not work.
Maybe the design of the universe prohibits time reversal, and the uncertainty principle is just a side effect of that prohibition.
Enough of my ramblings. If anyone is still reading this, and is familiar with the two slit experiment, I wonder what happens if you place two more slits where wave probability predicts some particles will go. Will the pattern of interference repeat?
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@SCPro Just a thought: You don't know what state the electrons/etc are in between the emitter and the two slits. You just know what happens when they (or it) passes through the one or the other (or both) slits. In short, all you can know is the interactions that constitute the experiment. The theories (equations) describe those interactions, not "reality", whatever that is.
@SCPro: That's a brilliant question, I hope somebody tries that out. I expect the same beam of light could be split into a cascade of alternating apparent waves and particles as often as you wanted.
It seems likely that the speed of the expansion of the Universe is related to the arrow of Time, so the question is: —is Space being created in the process?— If yes, the following question is:—is this the cause of the irreversibility of Time?
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Dennis Overbye is repeating an error that has plagued this subject “forever”. The reason time doesn’t go backward has nothing to do with there being countless more ways for things to be scrambled. After all, if time is reversible in the laws of physics then that reasoning would apply as well going backwards! As Feynman and Penrose have said, the puzzle is why entropy is so low to begin with. No one knows the answer.
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@Richard Swanson: Well, it's of some interest that entropy increases, and that seems to characterize the passage of time, from low entropy to high entropy. it's not an error to discuss that, it's a pretty major aspect of our world, the basis of a lot of engineering and so on.
The other question, of how come we started with low entropy (and the possibility of it increasing) is a whole other puzzle. Amateur as I am, I've never heard of any research or speculation on that question. It might be "just one of those things".
Time is a measurement develop by humans. It can be more accurate to define it like an unstop line.
1
An egg has "billions" of particles? No, an egg has quadrillions of quadrillions of particles. If it weren't for the tantalizing prospect of breaking cryptographic codes, quantum computing would be relegated to the bizarre outer reaches of human endeavor and justifiably ignored until to can produce something, anything, useful.
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@Brian No they think they can get other important simulations running that aren't possible classically, think weather, interactions of molecules, I guess even dna evolution into people maybe. But lets face it as we did with the Manhattan Project. If they don't get to crypto first someone else will.
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@Brian: I don't know, though, it's not that vastly expensive. I think some people would keep it going just out of curiosity. But you're right, a lot of the practical interest is in the cryptography angle, not in the salvaging broken eggs.
Sounds like undoing a change, not reversing time. If you do reverse time for a particle, where does it go? The Earth is both rotating and moving through space, traveling around the galaxy at close to 150 miles per second. If I go back in time a second, depending on where I am on the planet I'm probably ending up either in the outer atmosphere or deep in the crust
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I@Doug, I agree that the linear time sequence does not seem to be interrupted or reversed here, events seem rather to be reverting to their original state going forward in time.
It is fun to think about the nature of time but am certain that the past does not exist. It evaporates as the thin shock front of the present moves forward.
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@Doug: What you say seems right. And there is the thing about this being only a mathematical model. I think that when you start talking about a particle actually being where it was a fraction of a second ago, that's where the part about it being too unutterably complicated to ever happen kicks in.
Meh. I can pick up a ball that rolled off a table and put it back on the table, basically at will.
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The theological consequences of the article are significant. While the Creator allowed one to go both directions in each of the 3 spacial dimensions, (s)he only go allowed time time to go forward. Thus in the closed system of our universe,
disorder only increases. It's all downhill, so to speak. And consider that the life forms created on Earth could only imperfectly copy their hereditary information so new aberrant life forms appeared. Think of all those innocent anaerobes poisoned by those new green lifeforms that belched out poisonous oxygen. And failure to coordinate the revolution of the Earth around the sun with the Earth's rotation on its axis requiring the necessity of Leap Years. Then there is the failure to coordinate the two obvious features of that critical geometric shape,the circumference and diameter of the Circle. They're related by that never ending decimal number 'Pi,; Its totally irrational. I understand the Creator was tired and needed rest; but if s(he) would have only worked a little longer to correct the identified flaws. the World might be a more perfect, fulfilling and happy place.
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Time is not an unidirectional arrow. It is not reversible because it does not have any head. Past, present and future in quantum time is a futile definition because it describes as itself as undefined.
4
Artificial Intelligence running on quantum computers will fabricate multiple virtual realities that will be different time-states of created objects -- created realities, and in so doing, those objects/ realities will become alive imbued with a newly created intelligence that is an artifice of the maker's intelligence which is already artificial. The human who set all this in motion will be stuck in a quotidian path of time that will diverge from the many paths created by the computer and the human who reacts to this new artifice will get lost in the wilderness of all the created realities and become consumed by whatever is in there in that world the artificial intelligence of the quantum computer created. This will go on so long as the power plug stays connected...Sigh...The power plug will not be found by the humans.
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Time appears to be emergent, i.e., it's a consequence of increasing entropy (the universe starting with low entropy and increasing ever since, creating the illusion of time passing). IN other words, time is not fundamental. As long as the universe is in a state of non-equilibrium thermodynamics where heat energy only flows from more to less, the perception of time marches on but there is no reason why it has to.
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@A Goldstein
The reality of your « flow» implies both Space and Time... so, you need start over again...
2
So Herr Boltzmann had it right all along, and his conclusion extends even to the quantum level?!!
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This experiment looks analogous to the Hahn echo in nuclear magnetic resonance where an excited, initally phase coherent multi-quantum state, after some evolution/dispersion, is restored naturally (refocused) by an inversion pulse. So... a bit of hyperventilation it seems by the author-- as stated already by Robert Stadler.
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The one exception to this rule must be that everything, not just a single particle, can go backwards. To use the ripple analogy, when the ripple returns to time zero, the pebble must strike the surface. If you reverse the ripple, you must have a pebble.
Unfortunately, this is the same singular future played out in reverse: just Trump devolving to Reagan.
1
“The system comprising two particles is even more irreversible, let alone the eggs — comprising billions of particles — we break to prepare an omelet.” What if by going back even further (as suggested by BDylan) one could take the scramble from a high level of entropy to a lower level? See also for example, Anna Swir’s piece “Woman Unborn.”
1
“Quantum weirdness” - Now there is a scientific term.
“If you check the answer before the calculation is done - the answer changes?” I have tried to wrap my head around these concepts a number of times. All it does is give me a headache.
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Time doesn't exist as an independent reality -- it's a human construct, as many have noted. (Even stodgy old Kant got this right.)
Sure, things change and one can record/measure/remember those changes, but that only gives us humans a fictional notion of some invented dimension called "time." So, given that time doesn't exist, asking about its reversibility is nonsense. Likewise, phrases such as "the flow of time" are pure nonsense.
And, while we're at it: it's not just that the past and future don't exist, the present isn't actually here either. Once you see this, you see how wrongheaded this whole discussion is, and, of course, you've opened the door to a new way of experiencing the universe :)
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@Alan Cole I'm going to smoke some weed and read your comment again - that's going to be fun
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@Alan Cole
How can time be "a it's a human construct" if it must have have existed long before life on earth ever evolved?
Other issue is whether time is variable depending on factors like speed, according to the theory of relativity.
If time can slow, as demonstrated by the theory of relativity, how about the possibility that it can also arrive at zero - no 'time' at all.
Well, just a lay thinking aloud.
5
Thank god Alan Cole is here to tell us what the physicists won't!
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You Can't Go Home Again, Thomas Wolfe exhorted from the grave in his posthumous novel; we don't get to know if he still felt that way when his heart stopped beating. On the other hand George Bailey did get to go back in time to see if his very existence actually accomplished anything. Two notable and successful experiments by fiction writers.
I actually just showed up her to read the comments and see who would be weighing in. I was hoping to hear Donald Trump's take on the matters at hand but I guess he is too busy racking up impeachable offenses... leading some of the people who voted for him to wish that quantum physics could get them back into those 2016 voting booths...
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To me it’s simple in every day experience. Once the toothpaste is out of the tube you can’t put it back in its original state and I know nothing about the quantum mechanics
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@Eraven: Yes, that's the thermodynamics part: the quantum part is different, but seems to lead in the same direction, for once.
In other words you can’t go home.
2
I think this raises the question if we have completely misunderstood what time and space are exactly - e.g. try looking up an explanation that says what time and space are or what this "framework" or spacetime is or even what a dimension is.
I personally (with some theorietical work of my own) think Space and Time are particles just like light and mass - so space and time stretching is just the wave function of those particles losing energy and the wavelength of them stretching. My theory suggests space is a boson like light (but it always acts at right angles to light), and time is a fermion with spin 3/2 so is always beyond light from our perspective as we can only see mass that is between light and space, and the higgs boson is half way between the light and space boson - and why binding energy is so hard to measure as thats between higgs and space.
I think it is a major fault of Physics in general that any new theory to be accepted must first include all work of previous physicists like Einstien - what if special and general relativity are wrong, but just close enough to look like they are right.
Unless we have people that are brave to completely rethink what even a dimension is (as well as space and time), we will never understand dark matter and energy.
Current scientists can't just dismiss them as crazy (which I have had more times than I can count), many professors or Dr's won't even enertain the ideas I have had.
And thats a shame
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@Anthony Dean And perhaps for darn good reason after reading your 'explanation' here. Lots of lingo. I seriously doubt from your brief discussion you have even the slightest clue about the mathematics to determine spin and particle types. Sorry.
1
@Anthony Dean
You state, "... physicists like Einstein - what if special and general relativity are wrong, but just close enough to look like they are right."
Einstein is neither right nor wrong. He and his relativity theories are simply more accurate (More Right???) than Newton and his Newtonian physics.
And I find it amusing to read articles that essentially say, "I think Einstein was wrong. Oh wait... Never mind."
1
great comments, I appreciate those much smarter and more enlightened than I explaining this article - I have a question, why is there no concept of time in a dream? Dreams seem to happen in a vacuum devoid of time - some go fast some go slow but they never seem to have time. We speed all of our awake "state" in time - and lots of money/energy trying to define and explore time. And are animals aware of time? So is time a human thing that we created?
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@Theo Wilson
The posture, gesture and gait signal and symbol representations that structured sleep-thinking were adapted during the common ancestor's and the Homo habilis' evolutionary periods.
The common ancestor's posture, gesture and gait signaled language could not represent time and the Homo habilis' posture, gesture and gait symbolic language could only represent a very recent past and an about to happen future.
Dreams are conscious cognitive translations of sleep thinking.
With no pun intended, the representation of time is "lost in this translation."
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@george witt some of us actually travel in our sleep and visit other dimensions, some are visited by others from other dimensions
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Excellent question Theo. Thank you for posting this comment. Brilliant question!
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What if the Big Bang was a mistake?
I don’t refer to a scientific discovery mistake. I refer to an actual mistake from whatever it was that caused the Big Bang in the first place was not meant to happen and it just happened by mistake.
An error of cosmic proportions.
Just wondering.
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@Truth Is True - look it up, the idea was made by a Catholic Priest, so ironically is no better than saying God did it with extra steps.
I personally think the big bang is very short sighted thinking as the big bang theory breaks the law of conservation of energy for one - hense the short sightedness as it doesn't try and explain where the energy came from in the first place, if we have so much evidence to say it can't be created or destroyed now.
I like to think our universe is just one of many many bubbles, and energy is timeless - so universes can be created and destroyed but the energy that makes them also makes time and space as well as mass.
If you think of space and time as particles like mass - they can stretch by losing energy, and since space and light are being stretched then that energy must be given to something else, like binding energy or mass for example.
@Anthony Dean Perhaps you can cite some rigorous mathematical proof or beginning evaluation of the last paragraph. It would sound much more like a lingo filled paragraph than anything that has been proven so far.
@Truth Is True
The mistake of the Big Bang gave us the Beauty, and the matter to reflect about it in a timeless state, even its weirdness is awesome, isn't it?
"Unlike regular computers, which process a series of zeros and ones, or bits, quantum computers are made of so-called qubits, each of which can be zero and one at the same time".
Zero and one at the same time. It cannot be. Why not write: "at a given time, a qubit can be zero OR one--but we cannot know which is it". Schrödinger's cat is NOT dead and alive at the same time. We just don't know what his state is--unless we open that door.
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@Deus Ex Machina But that means it IS dead and alive at the same time. There is no other "truth". That is Quantum weirdness at its most basic.
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@Deus Ex Machina They ARE zero and one at the same time, and Schrodinger's cat IS alive and dead at the same time. Any old cat in a box is either dead or alive and, if the box is closed, we don't know which. That's no surprise. But a quantum cat is both. It's mathematically true and there have been experiments on cat analogs that demonstrate this. The wikipedia page on this is actually very helpful
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@Deus Ex Machina - this is because they talk in probability, when it can be both 0 and 1 (called superposition) and you only know which it is when you measure it.
Technically they should say it is in the 1/2 position or flipping between 0 and 1, as that would make more sense I think.
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In other words, anyplace you want to return to, no longer exists.
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@JTS
Well, anyplacetime, if you want to be accurate.
;-)
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I'd encourage the reader to temper their excitement until they've read commentary from some of the experts. For example, the MIT Technology Review published "No, scientists didn’t just ‘reverse time’ with a quantum computer". In addition, Scott Aaronson in his blog, offered this brief entry:
https://www.scottaaronson.com/blog/?p=4147
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Oh my! Has Picard learned of this? Quick - inform Data!
Can the quantum computer help us undo the 2016 election?
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@omedb261 -- And the Brexit please...
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@omedb261
That's probably your best hope.
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Integrated into any nuclear reaction; how fast would you say it could cool down a substance, and would there be time for this to reoccur; loss of power. Emergency systems can be turned on, is there any reason for fragmented particles to cause this abstraction and why!
Not a scientist, only curious. But do we know or even can we conjecture what happens when gravitational forces as strong as what occurs in a Black Hole manage to draw in a neutron star. Is it possible that the tremendous forces generated during this occurrence not only rips apart space, but also slows down or speeds up time?
@Birddog
My understanding is that time stops for the information that is on the surface of the event horizon when seen from the outside. On the inside we don't know but time would also have to stop at the singularity at the center, if in fact there is a singularity at the center. For objects that get close to a black hole but are able to escape the gravitational pull, time can slow down dramatically. This was dramatized in the movie "Interstellar" pretty well.
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@Birddog
Time is an illusion. If nothing moves, there is no time. If only one thing moves, there is no time. If two things move at the same frequency, there is no time. If two things move at different frequencies, but hopefully each
in a constant frequency, we have a ratio which becomes a unit of time. And with that we have a clock.
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@Birddog gravity is ripples in space time due to presence of mass. Massive objects like a black hole does rips space time in a relative way. Meaning it cannot rip space alone according to Einstein. Space time is a single entity. Whether it speeds up or slows down is a big mathematical and geometric problem I guess.
This article seriously misstates the nature of time. We aren't "always headed toward the future." Time is a dimension, and we exist in time just as we exist in space. We only remember the past, but this is a result of classical thermodynamics, not anything having to do with quantum mechanics.
In this experiment, researchers are not sending a particle backwards in time (at the quantum level, a regular particle travelling backwards in time is the same as an antiparticle travelling forwards in time). Instead, they are restoring it (at a later time) to the state it had at an earlier time. This is the difference between visiting Abraham Lincoln and using a skin cream to remove wrinkles.
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@Robert Stadler
Excellent comment. I was going to point out the article's naive (and erroneous) comparisons of time to an arrow and a river and a "flow," but you have said it better than I could have.
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@Robert Stadler
But the Schrodinger Wave equation does show negative time in the exponents and the possibility of that meaning that particles can go back in time is a legitimate reading of the mathematics of the equation. In the case of physics this has been explained as antiparticles going forward in time and that is something that can have physical existence. But that equation still suggests otherwise.
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@stadler
Perhaps he was referring to the human perception of time in that sentence and in others— he does refer (ref: Einstein) to time as another dimension of space-time.
Philosophy might suggest we really do not know the true nature of time anyway, nor the meaning (or understanding) of the uncertainty principle. After all, no one has provided THE definitive explanation or proof.
But I like the Abraham Lincoln metaphor.
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I think humans are currently enmeshed in a 4 dimensional world and constrained by the time dimension just as an intelligence, if it could exist, in a one dimensional world, would be bound by one dimensional reality. However because of the peculiarities of our human existence, in particular our ability to theorize, test and develop solutions, it may be possible for us to gain some control over the present constraints the flow of time imposes upon us... Quantum computers are definitely a step in that direction. What is considered reality today, such as our inability to stop/reverse or otherwise manipulate the flow of time, may morph into a wholly different reality just as the relatively simple advances in technology, such as human journeys into space appear to effect aging at a different pace than those of us left on earth. We are on the "cusp" of solutions and time itself may yield...eventually.
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photo caption: "In photography and film, a broken egg can be perfectly unscrambled to its original state. But in real life, quantum mechanics prevent even a single particle from reversing its own course through time." the irreversibility involved with a broken egg has nothing to do with quantum mechanics. entropy is well explained in terms of classical physics.
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and after the time travel back to an earlier stage the particle must disappear from our universe since our time has moved on, no?
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Here is an Old Limerick:
There once a Girl Named "Bright".
Whose Speed was much greater than Light.
She set out one Day,
In a Relative Way.
And Returned on the Previous Night.
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@Uscdadnyc, are you reversing time to bring us back to Larry Eisenberg's limericks?
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what happens to the entangled particle?
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@frank I believe they are stored in huge warehouses right next to all the extracted gluten.
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I knew it! This proves that The Matrix is real.
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What we really need is infinite improbability machine. If scrambled eggs reassembling themselves into uncracked eggs is the most improbable outcome nature can provide, an infinite improbability machine will ensure uncracked eggs are the only probable outcome given scrambled ones.
Of course, in order to render the infinitely improbable probable we need a finite probability machine first. Otherwise, how would we know the most improbable thing? In scientific terms, you need to achieve non-determinism in order render an improbable event probable. Once something is probable, it's going to happen. The question is where and when. The infinite improbability machine effectively renders this question moot because you've already solved the problem of polynomial time no matter how improbable.
The good news is a quantum computer can sometimes act like a finite probability device. The problem is the scientists are asking it the wrong questions. What's the point of a finite probability device if you're only going to ask it questions where you already know the probability? We need to know the probability of the improbable.
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@Andy
Yes, but where does the nice hot cup of tea come in?
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@Andy nicely done to both Andy and Sarah P
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@Sarah P
I think the universe is more of a peanuts and beer establishment but I never did quite get the hang of Thursdays.
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Ok. Fascinating, however (not to be picky) but this is not about time travel per se, i.e. literally sending someone/something in the past. It's about the "Benjamin Button" effect, i.e. reversing the state of something in the present to that something's state in the past, but still in the present time frame. If that was truly time travel one millionth of a second in the past, that particule would have disappeared from our present. But maybe I'm missing something.
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Well, I think the concept is that if you can reverse time for one particle, then in theory you can reverse time for, say the entire earth, or the entire solar system, or the entire universe, in which case everything around us would move backwards in time as well.
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@AJ Lorin
And if everything moved backwards, would we even notice that we had moved?
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@Bettina
Only if we could remember the future, which the present periodically reminds us we can't.
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