Because the entropy is minimal, researchers say:
n physics, this propensity of certain phenomena to occur in only one time’s direction is linked to their production of ‘entropy’, which is the physical quantity defining the amount of disorder in a system. In nature, processes tend to evolve spontaneously from states with less disorder to states with more disorder, and this propensity can be used to identify an arrow of time. Thus, if a phenomenon produces a large amount of entropy, observing its time-reversal is so improbable as to become essentially impossible. However, when the entropy produced is small enough, there is a non-negligible probability of seeing the time-reversal of a phenomenon occur naturally. Thinking back to the toothpaste example, if we were to squeeze the tube only gently and only a very small part of the toothpaste came out, it would not be so unlikely to observe it re-entering the tube, sucked in by the tube’s decompression. On the other hand, as the tube is squeezed with more strength, the toothpaste will spread out in an irreversible way, requiring a much greater effort if one were to put all it back in…
“In our work, we quantified the entropy produced by a system evolving in quantum superposition of processes with opposite time arrows. We found that this most often results in projecting the system onto a well-defined time’s direction, corresponding to the most likely process of the two” explains Gonzalo Manzano, a co-author of the study. And yet, when small amounts of entropy are involved (for instance, when there is so little toothpaste spilled that one could see it being reabsorbed into the tube), then one can physically observe the consequences of the system having evolved along the forward and backward temporal directions at the same time. As pointed out by Giulia Rubino, lead-author of the publication, “although time is often treated as a continuously increasing parameter, our study shows that the laws governing its flow in quantum mechanical contexts are much more complex. This may suggest that we need to rethink the way we represent this quantity in all those contexts where quantum laws play a crucial role.”University of Vienna, “In quantum mechanics, not even time flows as you might expect it to” at Eurekalert (November 29, 2021)
Cue time travel — but only if you are very, very small.
The paper is open access.
7 Replies to “FYI: In quantum mechanics, time may flow differently”
When has an actual gondolier ever been trapped in a time matrix? Pictures or it didn’t happen, as they say.
Non-physicist question here: Are they saying that time flows differently at different scales? Because even while a tiny system is occasionally going against the “arrow of time”, everything around it, including devices that we are using to measure/record the tiny system, are still marching in the more common direction. Frames of reference can be relative, but wouldn’t it be logical to consider the larger one more authoritative?
As to this finding,
Of related interest to that finding, and to clearly demonstrate just how much, shall we say, ‘disrespect’ that quantum mechanics has for the ‘flow of time’, in quantum mechanics it has now also been demonstrated that “a measurement in the future is able to reach back into the past and cause the photons to behave differently.”
As the following 2017 article states, “a decision made in the present can influence something in the past.”
And to clearly illustrate just how ‘counterintuitive’ this finding from quantum mechanics actually is, in the following 2018 article entitled “You thought quantum mechanics was weird: check out entangled time” Professor Elise Crullis provocatively states “entanglement can occur across two quantum systems that never coexisted,,, it implies that the measurements carried out by your eye upon starlight falling through your telescope this winter somehow dictated the polarity of photons more than 9 billion years old.”
And as if that was not bad enough for overturning our notion that the ‘flow of time’ is some universal metric that can’t be bent, or even broken, in Einstein’s special relativity we find that time passes differently for different ‘observers’ depending on how fast the observers are moving through space, “with time slowing to a stop as one, (an observer), approaches the speed of light .”
To grasp the whole ‘time slowing to a stop as one, (an observer), approaches the speed of light’ concept a little more easily, imagine moving away from the face of a clock at the speed of light. Would not the hands on the clock stay stationary as you moved away from the face of the clock at the speed of light? Moving away from the face of a clock at the speed of light happens to be the same ‘thought experiment’ that gave Einstein his breakthrough insight into e=mc2.
Moreover, the finding that time, as we understand it, comes to a complete stop at the speed of light is very friendly to Theistic presuppositions about ‘eternity’ and/or ‘eternal life’.
As Dr. Richard Swenson noted in his book “More Than Meets The Eye”, “The laws of relativity have changed timeless existence from a theological claim to a physical reality. Light, you see, is outside of time, a fact of nature proven in thousands of experiments at hundreds of universities. I don’t pretend to know how tomorrow can exist simultaneously with today and yesterday. But at the speed of light they actually and rigorously do. Time does not pass.”
Einstein himself alluded to the Theological significance of special relativity when he, upon the death of his close friend Michele Besso, stated, “For those of us who believe in physics, the distinction between past, present and future is only a stubbornly persistent illusion.”
Moreover, besides special relativity saying that time does not pass at the speed of light, we have ‘observational evidence’ from Near Death Experiencers who, consistently, testify that time has a radically different ‘eternal’ quality to it in heaven than does the temporal time that we experience here on earth.
Besides time, as we understand it, not passing at the speed of light, (nor for Near Death Experiencers), there is also nothing within the abstract, (i.e. immaterial, mental), world of mathematics,,,
,,, there is also nothing within the abstract, (i.e. immaterial, mental), world of mathematics, that dictates that time should only go in a forward direction.
As the following article states, “For years physicists have known that Newton’s laws, Einstein’s equations, and even those of the quantum theory, are all time-symmetrical. Time plays absolutely no role. There is no forward movement of time.”
And as the following article states, “if you simply write down and solve the equations governed by Newton’s laws of motion, you won’t get a single, correct answer. Instead, you’ll get two answers: one that corresponds to the ball hitting the ground in the future, and one that corresponds to where the ball would have hit the ground in the past.,,, In fact, there’s no universal rule at all that you can apply to tell you which answer is the one you’re looking for!”
Thus, “temporal’ time, as far as quantum mechanics, special relativity, and mathematics are concerned, might as well not even exist.
But anyways, to more firmly establish that ‘temporal’ time, as we understand it, must be a creation of the Mind of God it is important to note some of the defining characteristics of the immaterial mind that can’t possibly be reduced to materialistic explanations.
Dr. Michael Egnor, who is a neurosurgeon as well as professor of neurosurgery at the State University of New York, Stony Brook, states six properties of immaterial mind that are irreconcilable with the view that the mind is just the material brain. Those six properties are, “Intentionality,,, Qualia,,, Persistence of Self-Identity,,, Restricted Access,,, Incorrigibility,,, Free Will,,,”
Likewise, J. Warner Wallace has a very similar list, (but not an exact match to Dr. Egnor’s list), of six properties of immaterial mind that are irreconcilable with reductive materialism.
Of note: The ‘Persistence of Self-Identity through time’ may also be termed ‘the experience of ‘the Now”.
As to defining the specific mental attribute of the ‘Persistence of Self-Identity through time’ (and/or ‘the experience of ‘the Now”) in particular, it is first important to note that we each have a unique perspective of being outside of time. In fact we each seemingly watch from some mysterious outside perspective of time as time seemingly passes us by. Simply put, we seem to be standing on a (tiny) island of ‘now’ as the river of time continually flows past us.
In the following video, Dr. Suarez states that the irresolvable dilemma for reductive materialists as such, (paraphrase) “it is impossible for us to be ‘persons’ experiencing ‘now’ if we are nothing but particles flowing in space time. Moreover, for us to refer to ourselves as ‘persons’, we cannot refer to space-time as the ultimate substratum upon which everything exists, but must refer to a Person who is not bound by space time. (In other words) We must refer to God!”
In further defining the mental attribute of ‘the experience of the now’, in the following article Stanley Jaki states that “There can be no active mind without its sensing its existence in the moment called now.,,, ,,,There is no physical parallel to the mind’s ability to extend from its position in the momentary present to its past moments, or in its ability to imagine its future. The mind remains identical with itself while it lives through its momentary nows.”
And ‘the experience of ‘the now” also happens to be exactly where Albert Einstein got into trouble with leading philosophers of his day and also happens to be exactly where Einstein eventually got into trouble with quantum mechanics itself.
Around 1935, Einstein was directly asked by Rudolf Carnap (who was a fairly well respected philosopher):
Einstein’s answer was ‘categorical’, he said:
Prior to that encounter with Carnap, Einstein also had another disagreement with another famous philosopher, Henri Bergson, over what the proper definition of time should be (Bergson was also very well versed in the specific mental attribute of the ‘experience of the now’). In fact, that disagreement with Henri Bergson over what the proper definition of time should actually be was one of the primary reasons that Einstein failed to ever receive a Nobel prize for his work on relativity:
The specific statement that Einstein made to Carnap on the train, “The experience of ‘the now’ cannot be turned into an object of physical measurement, it can never be a part of physics.” was a very interesting (false) claim for Einstein to make to the philosopher since “The experience of ‘the now’ has, from many recent experiments in quantum mechanics, established itself as very much being a defining part of our physical measurements in quantum mechanics.
For instance, the following delayed choice experiment with atoms demonstrated that, “It proves that measurement is everything. At the quantum level, reality does not exist if you are not looking at it,”
Likewise, the following violation of Leggett’s inequality, (which falsified ‘realism’), stressed ‘the quantum-mechanical assertion that reality does not exist when we’re not observing it.’
The Mind First and/or Theistic implications of quantum experiments such as the preceding are fairly obvious. As Professor Scott Aaronson of MIT once quipped, “Look, we all have fun ridiculing the creationists,,, But if we accept the usual picture of quantum mechanics, then in a certain sense the situation is far worse: the world (as you experience it) might as well not have existed 10^-43 seconds ago!”
In short, ‘the now of the mind’, contrary to what Einstein thought possible for experimental physics, and according to advances in quantum mechanics, takes precedence over past events in time.
Moreover, due to advances in quantum mechanics, it would now be much more appropriate to phrase Einstein’s answer to the philosopher in this way:
Thus in conclusion, from every angle of modern science, i.e. quantum mechanics, special relativity, and mathematics, we have several lines of empirical evidence that all converge to the same conclusion. Namely, that the infinite, and eternal, Mind of God must be behind the creation of the ‘temporal’ time of this universe.
It seems to me that most all of the research in QM, clearly show that in a very real way, consciousness has to be a part of the system we call reality, or that reality has no meaning to begin with. We are too enamored with thoughts of Trillions of years and the Big Bang, but what did this time even mean before a conscious entity could mark or measure it? SURE we can picture massive amounts of time passing without our consciousness being around, but only by thinking about time and thinking about long periods and distances in space… We can think in terms of nuclear decay and use halflife to measure time… but even this has no meaning without a mind that can measure it and compare it…without thinking about, or converting input into conscious thoughts, there is no way to feel, see, or measure a material world… I think it goes a step farther… we can’t talk about a material world without thought and mind… I believe mind is obviously primary, but ironically it is our minds and inputs to it (like pain when we smash our toe) that make matter seem that it could be primary… if we move consciousness under Physics in the pyramid of science, it makes tremendously more sense. Also, interestingly enough, their are disorders of the MIND where people actually live out there life with everything whizzing by extremely fast… so in that person’s mind, reality is much different, no matter what billions of other people perceive. It is called tachysensia and for some it is persistent Also Alice in Wonderland syndrome… not due to a person’s input senses, but due to how the brain interprets the inputs.
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