Anyone who does not believe in reality of time should stop celebrating his/her birtdays.

Then, aging process is also not real. And the question who is older, father or son is irrelevant as well.

On the one hand, the dynamical laws of physics don't seem to contain a flow of time. Time appears in physics sometimes as a parameter, sometimes as a dimension resembling space dimensions. But there is nothing in the fundamental evolution equations indicating an asymmetry between past and future, or the necessity that times flows. The laws are invariant when we exchange past and future.

On the other hand, it can't be denied that time flows, in an irreversible way. From a reductionist viewpoint, if anything is reducible to physical laws, then the increase in entropy should give the arrow of time. The increase of entropy is not a dynamical law, but follows from an initial condition - the universe started in a state of a very low entropy.

I tried to explain how flowing time is compatible with the timelessness, and how free will can still exist, in my essay "Flowing with a frozen river" (http://www.fqxi.org/data/essay-contest-files/Stoica_flowzen_time_2.pdf), and in this paper http://www.noema.crifst.ro/doc/2012_5_01.pdf. Also see Scott Aaronson's inspiring essay "The Ghost in the Quantum Turing Machine" (http://arxiv.org/abs/1306.0159).

Penrose tries to explain the low initial entropy by conjecturing a special geometric property of the big bang singularity (I wrote something about the Weyl curvature hypothesis in http://arxiv.org/abs/1203.3382, 5 minutes audio slides presentation here http://www.unitaryflow.com/2013/09/weyl-curvature-hypothesis.html).

http://www.fqxi.org/data/essay-contest-files/Stoica_flowzen_time_2.pdf

I am impressed (although not a professional mathematician). I read your essay contest paper but ..... it seemed to me that you were constructing a possible alternative model that depends on a number of assumptions and is based on other theories rather than observations. For example every action we take is driven by the movement of electrons. These are affected by our upbringing, state of mind etc. but are not under our voluntary control. It has also been shown that our brains are preparing to act half a second before we consciously decide to do something as a sort of post-rationalization. The evidence is therefore that free will is an illusion, irrespective of the nature of time. Many people, including Hawking, for example, and, I suspect, yourself, dislike the implications of a universe in which time does not flow and have tried to find alternative models but so far without wide acceptance.

Thank you for reading and commenting my essay. Like I said, in the laws time doesn't appear as something flowing. According to them, time is an illusion. This is seen in their mathematical expression, although the laws were postulated following experiments, and tested by subsequent experiments, and the experiments themselves take place in time. But we have the impression that time flows, therefore somehow, something must happen to give us this feeling. It is an impression, so maybe it is not true. The fact that I remember now your question that happened previously is just a state in my brain. Each instantaneous state of the brain contains a picture of the previous states, ordered in an way which gives us the idea of time. So, I don't claim that time really flows, because there is no way to define this, there is no theory describing what it means to flow. All attempts to describe this are circular. I am happy with the idea of block universe, and I don't see why you seem to understand that I may dislike the implication implications of a universe in which time does not flow (in fact, I try to answer some questions in quantum mechanics, which is considered to be describable only by time evolution, using the timelessness of the block universe http://arxiv.org/abs/1309.2309, http://fqxi.org/data/essay-contest-files/Stoica_taoofitandbit_1.pdf). I did not try to find an alternative, neither to save the notion of free will. The idea occurred to me from quantum mechanics, which has a surprising feature. Most people think that this feature is randomness, and hope that randomness means free will. This is not true, since randomness is just randomness. Having my choices made by a die is not free will. The surprising and misunderstood feature of quantum mechanics is that the observed state depends on the property we measure. If we choose a different property, then we find the system in a different state. And this seems to affect the very initial conditions of the system, in the sense that if we entangle the observed system with another one, and delay the observation how long we want, we still observe that the original state depends on what we choose to observe in the future. This is the main mystery of quantum mechanics, and the conclusion people try to avoid by inventing non-local hidden variables theories, or many worlds etc., or by saying things like "shut up and calculate". So, what I say is that this happens in quantum mechanics, past depends on our choices. So maybe free will is just this, what we choose now, doesn't break the laws now, in order to fulfill our choice, but it applies since the beginning of the universe. This doesn't mean to change the past, just to delay the initial conditions that are not already decided. Now, you may think that I want to introduce this to save free will. Rather, I just want to raise this possibility, in order to consider it, before deciding whether it should be rejected or not. It is not right to proclaim the death of free will because we don't see it in the laws, we have to consider this possibility too, and in my essay I explain how could it be tested. Now you mention Libet's experiment. This experiment is correct, but what does it say? It just says that the decisions (which we consider to take place when the subject thinks s/he decides to make a movement), are preceded by the readiness potential. So, does this reject what I said, that our choice now affects the past in such a way that it lead to our choice? I don't think so, because the possibility I presented doesn't make predictions contradicting Libet's experiment. To summarize, I showed that there is a possibility that was overlooked, although it is suggested by quantum mechanics, and I proposed an experiment for this. There is a difference between saying that we should not overlook a possibility, and advocating the possibility as the correct explanation. The experiment is not feasible with the current technology, so people who think that a possibility should be rejected because it cannot be observed directly now, are free to reject it, although they may think they are not free :)

http://arxiv.org/pdf/1309.2309v1.pdf

There are many intuitive definitions of time, for instance the Italian poet G. Ungaretti wrote a very beautiful collection of poems "The feeling of time" (1933), but I think here we are considering the physical time. The physical time is a physical quantity that can be measured and, like all physical quantities, can be represented by a mathematical coordinate. The physical time is generally used for describing the evolution of physical systems by mathematical models which have different degrees of complexity. For simple degrees of complexity mathematical models, represented generally by sistems of linear differential equations, define accurately a time direction as per the Principle of Causality for which the effect follows always the cause. For high degrees of complexity previous mathematical models would be very complicated for which preferred mathematical models are statistical. In this representation of complexity the Principle of Causality loses its initial meaning and its validity at a point level but it is valid at a level of global variables (for instance the temperature of a gas system increases only after a cause determines it).

Therefore the different degree of complexity of systems doesn' t change the nature of time.

In the end I think the flow of time is in the reality of nature, independently of our representation, and therefore time is rather an enchanting river than a frozen lake, which inter alia in summer, that follows winter, changes and becomes a liquid lake.

Recently, a team at Trinity College Dublin led by Dr Kevin Healy announced that small animals with fast metabolisms experience time at a slower rate: – hence their extraordinary reaction times. Their work implicates the Flicker Fusion Frequency as a bio-metric that can be used to determine the exact rate (relative to our own) that an animal experiences time. Indeed, these findings chime well with the theoretic work done by professor Ram Vimal and myself in an earlier paper – see below.

The consequence of this work, although predicted by many philosophers and thinkers, is only now becoming fully appreciated. The knowledge that a mouse experiences time at a different rate to ourselves begs the question as to who is right? - The mouse or the human being?

A moment’s reflection reveals that there is something very wrong with our intuitive idea of what time is! The fact that there was something fundamentally wrong with a central aspect of my very existence prompted me to try to establish what sort of biometric could possibly account for the apparent ‘rate’ that time is experienced. In this way, I hoped, I would learn something about consciousness, and also, something about the universe around me.

Immediately I encountered a problem that seemed intractable. I designed a thought experiment to illustrate the problem (see paper below). I imagined that we had obtained a film of an alien scientist doing an experiment. We were able to work out from the experiment that the scientist was conducting (an experiment with cesium atoms) at what rate the film should be played. However, what we really wanted to know was at what rate the alien scientist was experiencing time. On reflection we realised that playing the film at the correct speed would only reveal how the events depicted on the film would have been experienced should a human being have been present. What we really wanted to know was how fast the film should be played to reveal how the alien scientist experienced time.

Luckily, for our analysts the alien scientist had a completely transparent head and we could witness every detail of his brain working. Also, there was a clock on the wall of the alien scientist’s lab. So, our scientists began to run the film of the alien in his lab at various rates to try to find a clue as to how fast the alien was experiencing time. As they ran the film faster so the various stimuli in the room would appear to occur faster and the corresponding neural firings in the scientists head were correspondingly faster. We quickly realised that every rate at which we displayed the film afforded us a completely physically consistent perspective on the events taking place in the film. So long as we used ‘time’ as it was displayed on the scientists wall then all physical events including the events in the alien scientist’s head displayed consistency with the laws of physics as we understand them! It seemed that from a perfect symmetry there emerged an asymmetry because there was only one rate that the film could be played that would reveal a consistent relationship between physical events and mental events!

From this thought experiment it is quite easy to show that no argument rooted in classical ‘cause and effect’ can ever give insight into what determines the apparent rate at which time is being experienced. From the perspective that the thought experiment affords it is easier to see that any explanations rooted in cause and effect are, in fact, tautologies that, at some point, use temporal duration in order to explain duration – the classic being – “Well, if metabolism increases and the brain works faster then surely, events will be experienced faster!” This may well be true, however, it does not come close to giving us any real insight.

I decided to change tack and, instead of trying to analyse the problem in terms of causal chains of events, I decided to analyse the problem in terms of experiences that do not change over time – pure tones. These types of experience are interesting for a number of reasons. The stimulus for such experiences is highly temporally structured, and yet, the associated phenomenology (what we experience) is totally invariant with respect to time!

The reason for choosing invariant experiences to analysis the temporal rate problem was that it seemed to offer a way out of the problem that kept recurring – brain states when viewed at different rates appear different and (seemingly paradoxically) consistent but with differing potential phenomenal experiences associated with them. With nothing physical to choose between the differing temporal perspectives the problem remained; Which was the correct rate? However, by considering the problem in terms of experiences that did not change over time, then , no matter at what rate the film was played there would still be a brain state associated with the stimulus that would be unchanged; Thus, one stimulus = one phenomenal state.

At first, I considered the possibility of utilising trivial invariant states: -trivial in the sense that it was only a macroscopic feature of the overall neural activity that remained unchanged. The underlying neural events that supported the macroscopic invariant feature, in fact, occured faster. Unfortunately, this approach did not seem to work for the following reasons:-

1. Attributing conscious states to a macroscopic collective behaviour of neurons seemed to require an epiphenomenal or supervenience approach that, as a philosopher, I have previously rejected as being Dualism in disguise.

2. Although tackling the problem from the perspective of invariant experiences seemed to hold promise, trivial invariance did not seem to provide anything in addition that could be meaningfully applied to the problem: -‘What biometric is responsible for determining at what rate time is experienced?”

3.

Upping the stakes I wondered if considering the possibility that macroscopic coherent states may offer a solution to the problem – perhaps a macroscopic BEC. Certainly, by postulating that an invariant coherent wave function may be associated with an invariant phenomenal state solves one aspect of the problem. At whatever speed the film is played the associated brain state appears the same and so the asymmetry disappears. Also, if consciousness is to be correlated with a macroscopic wave function there is an additional temporal quantity available that may help to solve the ‘rate’ problem – a quantity that is not a duration – Delta ‘t’.

The Fractal Catalytic Model of living processes implicates a macroscopic catalysing coherent soliton as the neural correlate of consciousness. This soliton is the fundamental carrier wave and it is variations to this wave that correspond to particular behavioural and cognitive states.

The maintenance of macroscopic coherent states with large Delta uncertainties places limits upon what sort of interactions and information transfer is allowable if the coherent state is not to collapse. How does the brain interact with the environment and maintain coherence? Is there any phenomenon associated with temporal experience that may offer us a clue? Yes, there is!

All nervous systems associated with higher order animals have associated with them what is termed a Flicker Fusion Frequency. The FFF is the frequency at which temporally structured stimuli are no longer experienced as structured but as continuous – like pure tones. The FFF for human beings is about 16th of a second. If a film is played at a frame rate less than this then flicker occurs. Sounds below this frequency are experienced as discontinuous – rhythmic or broken. Above this stimuli frequency associated phenomenology is continuous and invariant with respect to time.

What this implies is that experiences of frequency greater than the FFF have the peculiar quality of, on the one hand, being distinguishable from other high frequency stimuli, and yet, at the same time, we are completely unable to perceive their fine grain structure! Could the FFF be giving us information about the uncertainty in time for the Human coherent wave function?

If the brain interacts with temporally structured stimuli of a shorter interval than the Delta ‘t’ of the coherent wave function associated with consciousness then why does this interaction not cause the wave function to collapse? In lasers de-coherence is prevented from happening because the coherent wave itself triggers the release of energy from excited electrons in such a way that a critical transfer of information does not take place. The Fractal Catalytic Model considers the coherent solitonic wave function associated with consciousness as a catalysing agent in much the same way as the coherent light in a laser. Indeed, there is a raft of evidence now that demonstrates that the brain is not ‘hard wired’ to the senses; that the likelihood of a sense neuron firing is often influenced by the state of the brain (Davia, 2006).

So, the suggestion is that it is the Delta “t” associated with a coherent solitonic wave function in the brain that determines the boundary between what can de distinguished in time and what can not. And also, by implication, it is the quantity that determines the apparent rate at which time experienced!

We can now consider the theoretical situation where a sentient being with a very small Delta ‘t’ asks the question of a human – ‘When are you having the thought that you are having now?”. It would seem obvious that the answer is ‘Now’. However, if as is stated, the Delta “t” of the human is much larger than that of the question asker then, at least from the question askers point of view, there seems to be an ambiguity about whether the thought might also be occurring a little bit in the future and a little bit in the past!!! This would seem to have significance with respect to McTaggarts paradox. Also, we may be able to reconsider the conclusions of St Augustin with respect to the idea that temporal flow would require some sort of connection between what is about to happen, what is happening and what has just happened. Considering the possibility that consciousness may be correlated with a macroscopic wave function may allow for complex dynamics within the span of the ‘conscious moment’.

A metaphysical issue which this approach brings to the fore is the question as to where exactly ‘time’ is? Clearly, there seems to be at least two different types of time. There is the linear time – the time of flow that we infer from our experiences. However, if what I am claiming about the neural correlate of consciousness is true, then there seems to be another sort of time – a more fundamental time that forms a central aspect of the coherent wave function. Perhaps McTaggart’s was right – perhaps there is no time – out there! Time ‘out there’ is only implicit in the interaction between the environment’s structure/information and a coherent wave function – consciousness. Perhaps we do not represent an external space time, but rather, WE ARE SPACE /TIME???????

This metaphysical position is interesting from the point of view of Kant’s philosophy. He argued quite successfully that both space and time could not be synthetic concepts. This lead many thinkers to believe that we must be pre-programmed in some way. However, within the context of a quantum coherent model of consciousness, we may find that the reason why these concepts are a-priori is because both space and time form our basic ontology! WHATEVER THAT MEANS?

So, far the argument has focused upon our experience of the apparent rate at which time flows. We have ignored the problem of ‘time’s’ apparent directionality. It might seem at first that there is no problem, or at least, there is no issue of temporal directionality and McTaggart’s Paradox. But this may not be the case. McTaggart’s Paradox involves a distinction between past, present and future in terms of an inevitable direction and succession of events. However, if we consider the possibility that our experience of time is determined by a quantum coherent wave function then we find that the explanation for temporal directionality is not ‘on the same level’ as it is for the explanation for temporal rate allowing for the possibility that there may be a category mistake in McTaggart’s argument.

On the subject of Temporal Directionality

The FCM lies within the compass of dynamical systems theory and treats cognitive states as dynamic solutions to the boundary conditions imposed by the body and the senses. The invariant phenomenology of a pure tone is correlated with a non-trivial (i.e. coherent) invariant state in the brain. The invariant state of the coherent wave correlates in a simple way with the invariance experienced by the listener.

A key feature of this approach is the ‘invariance of the solution’ even when the stimulus and the associated brain state is viewed at different temporal rates. Although increasing (or decreasing) the speed at which these states are observed (eg, by using some sort of film), nevertheless the coherent solutions to these boundary conditions remain exactly the same! – i.e. one stimulus gives rise to one possible phenomenal state (not a range of possible states corresponding to different rates of temporal flow).

Although, these coherent states (or soliton solutions) may be claimed to be invariant (i.e as is the case with pure tones) they are nevertheless dynamic (perhaps in a way that we find difficult to intuitively grasp). They are far from equilibrium dynamic states.

Given that this model is correct in all the relevant details then we can come to some very interesting conclusions:-

Let us suppose that we run the film of the stimulus and the associated coherent brain state backwards! It turns out that an analysis of this film does not suggest that it is in any sense an impossible state to occur! In other words, strange as it may seem, whilst we claim that a brain state is intrinsically dynamic this in itself is not sufficient to claim that there is any associated directionality!!??

Can we really accept this idea? I believe that we can. Let us suppose that we alter someone’s brain so that they lose the ability to lay down memories. If we introduce a stimulus like a simple audio frequency then, given that the brain can no longer alter itself, it necessarily follows that there is no way that the listener can tell how long he/she has been listening – A second? A million years? From this it follows that, given this set of constraints, each phenomenal moment is exactly the same as any other! I do not believe that the experience (or concept) of temporal direction can emerge from such a set of conditions.

Even if we introduce the concept of phenomenal change – as in the case of a slowly ascending tone, if we still impose the constraint that the brain can not lay down memories, then, given that the same principle applies as when we reversed the direction of the film earlier in this analysis; that reversing the film still gives a view of a consistent physical scenario, then we must conclude that whatever the reason for our sense of the direction of time, it is not to be found within the conscious moment alone.

Give that the directionality of time represents a problem of asymmetry, we must search for its cause within an obvious asymmetry associated with brain function. Is there an obvious candidate? Yes, there is! If we listen to an extended note, say, C Sharp, played right at the end of Rachmaninov’s famous prelude, then, what we hear is somewhat qualified by the harmonies of the composers music. It does not matter at all that Beethoven’s Fifth is soon to be played. The point is that that brain contains information about events on one side of the ‘time-line’, but not the other!

From this I believe that it follows that although dynamic ‘phenomenal change’ may be intrinsic to the conscious moment and explainable within the physical dynamic correlated with this moment, this is not also true of our sense of ‘temporal directionality’. I believe that what follows from the above observations and analysis is that temporal directionality is a derived concept that was initially implicit in the asymmetry of information in the brain relating to events on the time-line ‘post and prior’ to experience.

So, to conclude;

Phenomenal Change (and indeed ‘rate’) is a-priory / intuitive and intrinsic to the special/temporal wave function associated with the conscious moment. It is fundamental to the ontology of consciousness and associated directly with the uncertainty in time of the coherent wave function.

Directionality is a synthetic concept that emerges consequent upon the informational content of the brain extrinsic to the conscious moment but which may nevertheless qualify or ‘prime’ particular conscious states.

Temporal Change (rate) = Phenomenology

Temporal Directionality = Psychology.

Davia, C.J (June 2006), "Life, Catalysis and Excitable Media: A Dynamic Systems Approach to Metabolism and Cognition", in Tuszynski, J.A,The Emerging Physics of Consciousness (The Frontiers Collection), Springer, pp. 255–292, ISBN 978-3540238904

Vimal, R and Davia, C.J . How Long is a Piece of Time - Phenomenal Time and Quantum Coherence - Toward a Solution (2008) . Quantum Biosystems. Editor in Chief – Pregnolato, Massim

Dr Kevin Healy et al “Time is in the Eye of the Beholder ” - The full paper is available here:http://www.sciencedirect.com/science/article/pii/S0003347213003060

An interesting philosophy class on the brain of mouses, humans and aliens.

These are all interesting contributions but we need objectivity. Children feel time passing slowly on Christmas Eve and faster in the last days of the school holidays. Perhaps we could measure the minimum screen refresh rate that eliminates flicker, which was used by the animal researchers as an indicative measure of the subjective passage of time, to see if it changes in humans under different circumstances. People with Parkinson's Disease slow down both objectively and subjectively (I have PD myself, so I know!). I am going to see if I can set up some software to show images at different refresh rates so that I can do some research.

One of the things that puzzles me is the entropy gradient in time. Time is not laid out as a random arrangement. If there is no cause and effect what creates the smooth gradient? How do the molecules of one time quantum know where they were in the previous quantum? If they don't know, then how (and why) is there a smooth gradient?

Stephen, raise very exacting questions. I agree with you on the subjective feeling of time, like it happens for children, for old men and for people suffering from diseases (I give you best wishes for good health also in the presence of your disease).

With regard to the entropy gradient I think it confirms the directional flow of time and the Principle of Causality. In fact if we suppose, for instance, that all in the universe is immobile, then we have the maximum order. When a force (cause) is applied to a body or a bodies system, they accelerate and move (effect) and simultaneously the disorder increases and it is in accordance with the entropy gradient. Is acceptable for you this explanation?

Daniele - your explanation is a good one but I wonder if entropy has any meaning in a Universe where time stands still? I guess it does because, even in a static universe, we could in principle determine the likelihood of a particular arrangement of molecules and a low probability would imply low entropy. In this case you are right - the entropy gradient is evidence for cause and effect. Not yet a formal proof but strong evidence.

Christopher I read this with interest too - i was even reported in The Economist. I don' think here is any question of the eel or the fly being right or wrong. Time does not change, there are simply different perceptions of time. Our inability to define the speed at which time passes was one reason why philosophers who deal with this question concluded hat (the passage of) time is an illusion.

Stephen,

I think that there is a problem with the whole idea of time flowing.

Considering the problem of a fly vs a human - which one is right? - I think that the thought experiment shows that the whole idea of time flowing is at fault. I don't pretend to know the correct way to think of time, though.

You might find the work done by Prof. Ram Vimal and myself of interest. The empirical work of the teams in Ireland and Scotland accords well with our own theoretical analysis - the rate of metabolism or (more precisely) the Flicker Fusion Frequency is an accurate bio-metric that can be used to determine the rate at which an animal is experiencing time, but it is not the primary cause.

How Long is a Piece of Time? Phenomenal Time and Quantum Coherence. Toward a Solution Vimal (Ram Lakhan Pandey) & Davia (Christopher James) Quantum Biosystems, 1(2) 102-151, Editor Massimo Pregnolato

Christopher - thanks for this. I am interested to find out whether individual human experience of time varies and whether certain diseases like Parkinson's cause changes in the FFF.

Stephen,

I watched an episode of 'House' and, apparently, one of the symptoms of ''The Plague' (bubonic?) was distortion in time perception!

Also, I am sure that we all experience time slightly differently. I wonder if sportsmen and women sometimes have an advantage because they experience time at a slower rate than people who are less 'talented' - just a thought.

If the FFF is linked to the rate of metabolism then any disease that slowed (or increased) the rate of metabolism in the brain should have an effect on time perception.

1. Not all perceptions are illusions. This is the reason why we try to filter this out by backing up our observations (whether in the natural or experimental conditions) with theory and more observations.

2. Our ultimate reference is light. Since the Theories of Relativity (by Einstein) are so far good in approximating the behavior of the Universe, we can glean something from them: That the absolute "rest" is light. Time can only be measured relative to light.

I however, like that the more fundamental reference of "time" is that "Cause precedes effect."

Johnrob Bantang

At the speed of light time stands still. Photons live for ever. But ... time stands still relative to what?

To the light. If one would notice, c is ubiquitous whenever time t is involved in relativity equations. In fact, our reference whether a particle would "travel back" in time depends on the ratio of its speed with that of light.

It is suitable to specify that at the speed of light time stands still only inside Lorentz' s Transformations and theories that use those transformations. In general we can say the speed of light and photons is not infinite but it has a finite and known value: only at infinite speeds time stands still, because constant, but infinite speeds don't exist.

McTaggart's Platonic neo-idealism is based, from the scientific viewpoint, on an erroneous hypothesis: past, present and future are equivalent states of time. It is manifest that it is not true because only the present observer has a physical meaning for describing a real event. The past observer and the past event don't exist more and the future observer and the future event could not exist. If one wants, he has full consciousness of past, present, future and flow of time.

The verb to "flow" requieres two variables to treat it mathematically. As long as we consider only one time variable it is not posible to speak of "time flow". Nevertheless, if we use two time variables according to the Newtonian dual concept of time, then we can use two variables, say t an Tau, as shown in the attached article, therefore we can define "time-arrow" and "time-flow" mathematically.

Iván - Of course you can hypothesise a second time dimension in order to measure the rate at which the first flows but the second dimension must also flow and do you not need a third to measure the second ..... and so on ad infinitum ......?

No Stephen, my proposal is not a second time dimension, it is to reintroduce newtonian absolute time as a scalar variable T (indepèndent of reference systems) without detriment of the fourth coordinate x4=ict of relative time. The results I obtained are interesting. Please take a look at my article. Time-flow is given by dt/dT=1 in the rest reference system-

Time flow is right because we feel time individually and we are getting old and no return to our young period is possible. We undergo time all over our life. It is a unidirectional arrow to forward direction : Future. A natural clock in solar system indicates the elapse of time based on the translation and rotation of earth and moon around sun.

Can you reverse the rotation from CCV to clockwise ? why is it counterclockwise?

Time exists even there is no motion, and we get old due to our biological clock even we stand stationary.

On the other hand, Galilean and Lorentzian transformations are correlated to absolute Newton and relative Einstein concept of "Time". Each one may be correct at certain conditions.

Time, it is true, always moves from past to future and is irreversible, Parviz. But according to the philosopher Xavier Zubiri ("Dynamic Structure of Reality,") "with the quantum of time comes age. But age does not necessarily coincide with the quantum of time. In any case age, as a biological time, is not reducible to the temporal parameter, to the f (t), the function of time which mechanics introduce into its equations."

Check your own experiences: how accurately can you estimate with your eye the chronological age of everyone you meet?

Biological time is measured by human inherent clock and physical time according to motion is measured by conventional clocks. We may assume both to be identical , however Time in various coordinates may be different.

Parviz, I strongly doubt the identity of intimate biographical time and clock time. Here is my proof: if, like me, you are not fond of looking in the mirror at your own face to ask how old you look, observe the face of a dear parent as he or she ages over the years. Some movie stars-- and even some ordinary folk-- do not seem to age as quickly as others. Plastic surgeons will tell you this. The cause is an easier lifestyle (leaving aside plastic surgery). My mother until her final two decades always looked younger than her chronological age and had no health problems. In youth, she was often taken for my sister. Then in her middle 80s she aged rapidly and declined until passing away at age 94.

Nelson, the biographical clock finally rings death and it is absolute fate for any individual. On the other hand, the physical time may dilate in high speed motion or around black hole where the space-time curvature takes place to dedicate us long lasting life!

It seems that all the comments insist that there is a flow of time. If you are all correct then:

1. Do you believe that the past still exists?

2. Do you believe that the future exists?

If the answer to either of these questions is "No" then do you think Einstein and/or Godel are wrong?

If your answer to both questions is "yes" then

(a) is the flow of time universal (the same rate for everyone)?

(b) if so, "why", "how do you know", and how is synchrony maintained? or

(c) does it flow differently for everyone?

(d) if so then I would argue that the flow of time is subjective and indistinguishable from an illusion.

I have no preference and I behave as though my decisions are my own and have consequences because I am impelled to, even though ], when I inspect them carefully I can see that they are really involuntary. Animals cannot ponder a dilemma as language allows humans to but the evolution of language does not alter us any fundamental way. We are still animals but with delusions of grandeur.

I added the following to the article of Parviz Parvin just a second ago; those fundamental thoughts may be of interest:

Your question about time is fundamental, and unsolved. Personally I understand time like Aristotle. A friend of mine pointed me to his thoughts. There is movement and things spatially move or get moved. But there is no time what goes on! Time and space are constructions made of people and used by people. It helps to calculate and give orientation. But I think it is only a construction, not more. We better don't put time in the first place and movement in the second. If we do it leads us to all kind of thoughts what else this (invented) time-construction would be. We need to keep in mind that all there is, is movement. Why I think so? Well, take a seat, settle down, take a few moments and look around. What is there to notice a difference between moments?

Having this done it is obvious why we introduced the construction of time. And it is obvious why this construction of time works great for calculations and why Newton and Einstein and so on take this as common ground for their knowledge. And it is right to do so. We better just don't confuse the reality of movement and constructed time so we don't lose the red line.

Time appears to be a consequence of (material + efficient) cause-effect relation. I would believe that time appears as an illusion as far as SR and GR proposes it. In fact, time is only relative to light (both in it's constant speed in vacuum and it's straightness of path). Light is the absolute reference (not a frame, but a thing).

"All there is, is movement." I think this is true. Philosophically, all potentiality (potentia) has to become actuality (act). This process of change has been called "motion" (Aristotelian concept). Today, motion has been narrowed down to "locomotion". Becoming actuality is a sense of perfection. Everything "wants" to be perfect because everything is in motion.

The "movement of time" can be thought of the attainment of greater perfection of the Universe as a whole, taken as the great connections of cause-effect relations.

There is a true flow of time that is irreversible therefore the past has been ended and the future depends on all present activities. Time is flowing with a certain rate that is determined by our solar system clock ( regular spin rotation of earth around sun) . However, the time flow rate may be inherently synchronized with our biological clock. If one stays immobile, the time flow does not stop and we get older naturally.

Time is a true physical dimension because creates the sequence and without this important parameter, all activities occur simultaneously and you will have eternal life.

Peer, Johnrob, Parviz - The implication is that you each think that the theories of relativity are wrong. Can you explain why and/or what is necessary to correct them?

STR and GTR are interesting theories but are not perfect. The particles are currently accelerated in synchrotrons up to nearly C. To my knowledge, no time dilation happens for them ?!

The half life of unstable particles in cosmic rays is extended in accordance with the ToR,

I don't think that the theories of relativity are wrong in general. I believe strongly the Principle of Relativity. I think Special Relativity and General Relativity are obsolete theories. I said and wrote it very often.

With regard to Special Relativity I have demonstrated in TR (Theory of Reference Frames) that Lorentz's Transformations aren't able to describe correctly kinematics of space-time for inertial reference frames. Those transformations involve a series of inconsistencies and contradictions: velocity loses its nature of vector quantity and becomes a scalar quantity, mass loses its nature of scalar quantity and becomes a vector quantity; there is an inversion in physical properties of mass and velocity. Besides any mass at the speed of light c is infinite (?) because the speed of light is considered in SR a maximum speed and it implies a time dilation (?) and a length contraction (?). Etc....

With regard to General Relativity I have pointed out, always in TR, that is is based on a "principle of covariance" that has nothing in common with the Principle of Relativity that instead is based on a "principle of invariance". I have pointed out that in GR the definition of element ds (linear or non linear) involves the use of imaginary (non real) coordinates.

I have pointed still that this element has no physical meaning, because in physics each concept has to have its own unity of measure and that element doesn't have it because at times it is measured by real unities and at times is measured by imaginaryn unities.

Stephen, with regard to the average life of cosmic unstable particles, it is known that cosmic muons wouldn't be able to reach the surface of the earth at the speed of light.

The problem in SR is solved making use of the time dilation.

In TR I have demonstrated all unstable particles have speed greater than the speed of light and therefore that problem is solved otherwise.

Stephen, sorry for my late reply.

Well, I am not in the position to judge here, specially not such complex theories etc. . But here is what I noticed after having talked with a friend about this time issue. It seems the majority of physicists 'believe' time is real (like I did once..). And I say 'believe' because we have consequential and mathematical proof that time can not exist (e.g. Aristotle, Kurt Gödel and Einstein). When we use 'time' in equations to work with theories we better keep in mind that time is a 'theory' and not more than a tool. Time was made up as a tool for calculation, orientation and organization. Thinking about accelerating or decelerating time won't lead us nowhere, it will only take out the reason for its existence ( for calculation, orientation, organization and possibly others).

Just a few words about the misleading assumption the biological clock, solar system clock(s) and simultaneously activities etc. could depend on 'time', they can not and they do not. Those thoughts are based on time as a 'constant time flow'. All those issues are happening, but independent of any tool called time.

This is how I think about time. I am not sure if I found the right words, but I am trying.

Peer,

While it may not be appropriate here, I would like to hear how you conceive of motion.

Peer

This is exactly how I think of time. We have a system of accounting for different arrangements of matter at different intervals in terns of rates of change and cause and effect, which is perfectly valid as a mathematical model but the idea of change as real is so deeply embedded that we cannot easily give it up. I suspect that we need to have a new deep understanding of the nature of time to make sense of quantum theory and string theory. Most of the contributors to this thread seem unable or unwilling to try and accept that time cannot really flow

Peer

If you were ever- young human kind, I could accept your assertion!

Our biological clock is a fact and everyone has got his own clock.

However, I believe that the biological clock does not run similarly for different individuals. Some people get old faster than the others, likely due to the ways of life: stress, hard working, inconvenience, genetics(the inherent malfunction of biological clock) etc. and vice-versa. Time flow would slow down for us drastically , if we are young forever.

It does not happen because of the word "old" is opposite of "young" and is a reality. I have not found elixir yet, capable of prolonging life indefinitely !

Stephen

Rate equations deal with time flow!?

Dear Parviz,

I wonder - why would evolution go to all the trouble of providing us with a biological clock given that we evolved with giant a clock all around us - the earth and heavens?

Wouldn't it be more accurate to say that we have evolved biological mechanisms that entrain themselves to temporal structures in the environment?

Also, every bacterium in the ocean may represent a continuous process of metabolism stretching back to the beginning of life on this planet. I do not believe that the concept of 'old' is a necessary one when considering the fundamental nature of life.

Chris

Dear Christopher

Yes. According to DNA we are very old but we still evaluate oldness with a certain tool: time flow.

The Universe is not vast - nor old,

But I am small - and the entire labor of my life,

Encompassed by a mote.

Stephen,

I agree totally. Since our group of physicists left the path of 'philosophy' (what I recently learned is in its origin equal to 'truth') we assume our theories can be true. And this is fatal. I think we need to keep in mind what is theory and what is true and we better know at least a bit of both. It seems to me 'modern' theories require an understanding of e.g. the tool of time or of the difference between time and movement (Aristotle, not Newton) otherwise we get stocked and lost somewhere. I have to admit I would probably never have thought about this issue if there would not have been a friend of mine who is actually thinking about those things. And I am in physics for so many years ...

David, but also to Parviz,

I understand movement as the only thing what really 'happens' around us (and I call it movement since motion for me is more like a steady move, but possibly motion fits even better, I can't tell). An example: You take a seat somewhere in the nature. You forget about time. You forget about sounds. You 'vacuum' your mind. Now you are able to see what there basically is: Movement. Nothing else. Birds move, snails move, you see day and night, living beings move; stones and mountains don't move. You can define things and happenings by movement. If you look at a few rocks you probably don't see lots of movements. It is just there. So what makes the moment of now different to the next moment? Nothing. And everything around you, what cares about one moment and about the next moment? Nothing. It only counts if there is a movement, this is what makes the difference. And now instead of seeing just those movements as movements you can see all processes of life the same way; at the end it is somehow movement.

This is a good moment to mention why I think time could have been introduced. If you want to tell someone how long it takes to go somewhere you better use any kind of periodic event. Both parties know how many times e.g. the sun goes up before you arrive there (assuming you walk the right way). And it works for any kind of calculation, forecast etc. At least as long as you keep it a periodic event and don't change e.g. the speed. But we introduced the time to give a name to this moment and to the next moment.

Peer,

Thank you for your thoughts. If we take as given that time is a measuring/organizing tool (created by our consciousness), can we go another step on that path and think of motion being similarly inferred by a sensation giving rise to a memory (of a moment) with another sensation giving rise to a second memory (of a moment) and so on - with the memories then being compared, one to the other, resulting in the appearance of movement?

Remind that without time flow, there is no time sequence and then all events( in past,present and future) simultaneously happen. Time is not an illusion, it is a fact of nature.The measuring instrument is a clock. It could be any natural periodic system including any regular rotation in solar system and spin rotation of earth or our biological clock ( being hungry and thirsty regularly, etc) or our low and high precision human made clocks. We have synchronized them for the efficient utilization.

peer,

Stone also has a great no of movements similar to all other objects: motion of particles inside such as atoms,molecules and electron motions. The time scale for those particles may be different.

Some consider the physical time, others consider the philosophic time. Physicists have to reckon with reality through experiments. Philosophers don't have that exigency. Difference is here.

David,

I am not sure if I understood what you are saying, it's complex. But the more I read your sentence the more I think that's it. Like single events added one after the other become 'motion', right?

Parviz,

I don't know what else to write. This matter of time allows everyone to think whatever he prefers. If you think time is a fact of nature than there is probably no one who can change your mind but yourself. As long as it works for you it won't bother anyone I guess.

Daniele,

the previous mentioned recent conversation I had with that friend of mine made me rethink the general approach of phycisists. Isn't it that physicists often confuse theoretical models with reality? I know more than one who

actually believes our theories and models are real. Look at the quantum theory as one example. Take the time as another. Or take a look at our models explaining light (wave-particle-duality). Being very focused on a model/theory often let us forget the core: The truth, ... (usually) the core of philosophy. Having this in mind I totally understand now why philosophy has been the main subject in ancient times.

Peer, the difference between physics and metaphysics goes back to Aristotele. The Aristotelian philosophy has dominated till the seventeenth century when Copernico and Galileo proved the Aristotelian physics was outdated and they replaced the geocentric universe with the heliocentric universe. Today we know that also the heliocentric universe is outdated and all in the universe is in motion. In ancient times philosophy was dominant because thecnology wasn't able to give opportunities that it gives today. For instance it is clear when we think about the evolution of clock, but it is valid for all physical quantities.

Physical quantities that we use (space, time, speed, temperature, electric charge, electric current, etc...) are physical quantities constructed by men, like also reference frames, but they are necessary quantities for defining the reality and the universe. We know very well used models can be also wrong or inadequate and therefore physics isn't a static subject but is a subject undergoing rapid growth. We don't confuse models with reality and in fact when a model seems outdated we strive to replace it with a better model.

The job of researchers is just that and it is what I strive to do, for instance when I thought about the Theory of Reference Frames. We aren't interested in the absolute or divine truth which are subjects for other matters, we are interested in the human truth that is available for men and is within the limit of the human mind.

I'm sorry that your belief and belief of your friends in science, in physics, in reason and in experimental method is a bit weak.

Peer,

Once again, thank you. It is analogous to how video imparts the "sense" of motion by running frames in a sequence. I'm thinking it through on the assumption that what we call "physical" time does not describe reality in any way. Then, what would the implications be?

Daniele,

You are, of course, at the heart of many issues. Your contrast of physical time vs. philosophical time (what I conceive of as "mental time") points to the assumption of physical time's existence. Some suspect that assumption may fruitfully be questioned, and ultimately tested for - despite contrary, very impressive reasonings, experiments, and data.

David, when you fix an appointment do you make use of philosophical time (mental time) or of physical time?

Physics deals with time flow and time sequence and temporal rate equations etc. Even, the uncertainty principle correlates the lifetime( a temporal parameter) with energy spread.

It is true, Parviz, that the uncertainty principle correlates in indefinite manner time and energy, like position and momentum but I have demonstrated the uncertainty principle is based just on an outdated mathematical model and therefore that principle doesn't answer more in satisfactory manner to our exigencies to understand the reality.

Science is about what we can prove; religion - in its very broadest sense - is about what we believe. In principle neither need have anything to do with the other. Arguments can arise, however, when (a) what has been proved (eg the age of the planet or the heliocentric solar system) conflicts with a widely shared belief or (b) a scientist (eg Dawkins) tries to insist that everyone accept what, in his opinion, is a proven truth or a believer (eg a religious fundamentalist) insists that everyone accept his beliefs as truth and behave accordingly.

As a scientist I accept that the flow of time has been proved .to be an illusion and that we (as scientists) must rethink our view of the universe accordingly. I am pleased to find others who share this view and like to discuss the implications. Most of my scientist friends do not but we don't talk about it and are still friends. I asked this question in order to find out how widespread the acceptance is (not at all apart from Peer K) and if anyone had any logical convincing arguments to support their disbelief.(none at all).

One thing puzzles me - if time and space are quantised at the Planck scale and time is invariant, what is the origin of the continuity that we observe at the macro scale?

Daniele,

Thanks for the question. This will likely not persuade, but I suppose one must walk before one can run.

I have an appointment to go fishing at a nearby lake. My memory advises this will be possible when the season differs from what my consciousness currently perceives/conceives. My consciousness then uses memory to inform me the season has changed (i.e. my memory plus awareness, the “awareness” probably forming a new memory, forms a calendar). In this case a “clock” is when the ice is off the lake. To communicate meaningfully about this, we need a consensus-based calendar and clock. So I can (optimistically) say the consensual calendar indicator is the first week of June and the “clock” indicator is contingent.

I see only consensual “clocks” – and they can be what we normally use or “the ice is absent”. My understanding would not persuade me to think hard about “time” were it not for work (e.g. Edward Anderson, 2009, 2012 summaries) suggesting there are unresolved related issues in the physics realm. I simply do not see time anywhere but within our conceptual (and usually consensual) apparati.

Daniele

Uncertainty in a typical atomic transition:

Delta E * Delta T ~ h/2 pi

Delta W * state lifetime ~ 1

lifetime ~ 1/A , A is the Einstein coefficient for spontaneous emission.

Uncertainty supports to estimate a sensible time parameter.

Stephen, it's manifest that we have different viewpoints on physics. However both viewpoints are legitimate. The difference between believing and accepting is very subtle. I think accepting is to believe without convinction, and believing is to accept with convinction. With regard to the Planck relation, it proves only energy emitted by atoms, when unstable electrons pass from an energy level to another, is quantized. The concept that a quantization of space and time arises from that is only a hypothesis that some accept and others don't accept.

David, what you say about time is valid for all physical quantities. For example I can value a distance, and then I can make use of a calibrated rod in order to knowing the precise measurement. It is clear that physical quantities are inside our mind and memory after our experiences. Then I can decide to use conceptual clocks or natural clocks, like the state of ice, or instruments clocks.

Daniele

Uncertainty in a typical optical resonator:

Delta E * Delta T ~ h/2 pi

Delta W mode * photon lifetime ~ 1

Photon lifetime in cavity =Tp = (c/2nd)/1-R1R2 and R1,R2 are reflectance coefficients.

The frequency spread of the axial mode generated in the resonator is correlated to the inverse of the photon lifetime. Longer Tp shows narrower band of the modes and represents a selective sharper frequency width.

Again,

Uncertainty supports to estimate another sensible time parameter: Photon Lifetime in the resonator.

Parviz, the problem you raise is very technical. We know frequency spectra in the energy emission of atoms are measured with a greatest accuracy to the level of hyperfine structure. I think the uncertainty principle isn't useful to describe those events.

In fact in that case DeltaE represents the energy known jump and doesn't represent the indeterminate observable of energy.

The Einstein coefficient for spontaneous emission refers to the law of emission for a great number of excited electrons. Here the probabilistic meaning of the Einstein coefficient is connected with the aleatory nature of the process, considered for a great number of particles, and not with the uncertain nature of the same process for a single particle.

I think definition of time doesn't require a procedure of uncertainty.

I wrote my comment without reading your last comment.

Daniele

Exactly, it is written for populated levels and not for a single atom:

dN / dt = -AN, where N is the instantaneous population of the state.

I intended to show the significance of time in quantum theory of emission, where the energy spread of an exited level is related to the inverse of level lifetime. In fact, for a broadened level of atom, the lifetime decreases, namely the populated level is deactivated faster than a narrow sate. A=Delta W and spontaneous emission rate correlates inversely to lifetime. Alternatively, a forbidden level is characterized with a very narrow exited state or very small A.

Parviz, your considerations are very interesting because your reasoning relates the grade of stability of a level or band of energy (great lifetime) in inverse proportion to the energy spread (small DeltaE). Consequently the remotest levels from fundamental levels of energy are less stable. It explains because electrons tend to fill the most internal levels. This reasoning on electronics of the solid state is very interesting.

Stephen,

what you experienced with your colleagues is what I experienced too. It looks to me like consequences out of this 'dilemma' (time does not exist) are "inconvenient" so it is 'ignored'. This is what I meant (above) "confuse theoretical models with reality".

I gave examples where we possibly can see implications you mentioned. I like to add that our common understanding of time is so 'fundamental' that it is giving hard times to all of us restructuring our thoughts consequently. I can observe all the time how we reflect on issues don't remembering this fact of time (knowing it is proved already).

I can't follow your question you mentioned specially since you give time as invariant. Why would that be?

Daniele,

I wish we would not mix theories/models and reality, this is how it is supposed to be.

David,

As long as we distinguish between the tool of time and our reality I don't see issues, just 'forgetting' can cause trouble.

I can't know how you feel and please correct me when I am on the wrong path but I don't have the guts to speak out what this would mean e.g. to the theory of relativity etc. , do you?

Peer,

If one seriously questions time’s existence, as numerous physicists and others do, there must be significant implications for our understandings of physical and mental universes. Current understandings of the “physical” universe are invariably based upon the assumption of time’s existence in one form or another. Perhaps we could be less concerned with existing structures and try building anew, with revised premises, and see how the effort works out. What might Newton devise were he to try explaining the solar system’s movements with e.g. Stephen’s, Daniele’s and/or Parviz’s knowledge and data at hand and an assumption of time’s nonexistence?

I suspect there are endless problems associated with utilizing the “time” concept. For example, if we dispense with time, we probably dispense with motion and duration. If “time” and “motion” are problematic, perhaps neuroscientists would not look so diligently for optic and/or neurological mechanisms for detecting “motion”. That is why I asked you about motion originally. If motion isn’t there, what is happening? If time and motion are not there, we are misunderstanding ourselves and our universe. Implications and experiments are needed. Most have access to an immensely powerful large-concept-collider (LCC) in our heads – but it certainly takes energy to operate.

Universe is a dynamic complex system while from small distinct fm/pm/nm scales up to solar light measure for far distances, all deal with " motions" in different scales. Motion in subatomic scale is known as atomic transitions and correlated photons.

On the other hand, an excited atom may function as a precise clock due to its reproducible level lifetime.

We have no difficulty dealing with differential equations in the cartesian plane (dy/dx) and there is nothing intrinsically different if we replace x with t. Movement does not imply or require a flow of time.

One of our difficulties is that we are looking at the Universe through the wrong end of a telescope. Evolution has led us to look at the world on the human scale. We measure things in human scale units: seconds, minutes and hours for time, meters and centimeters for space and grams and kilograms for mass.

The natural units, however, are the Planck units:

Time 5.39912 x 10^(-44) seconds

Length 1.616 x 10^(-35) meters

Mass 2.176 x 10^(-8) kg

In an earlier post on this thread I wondered about the continuity of the Universe in space and time. I was thinking then about the steep gradients that we often observe in the quantum states of adjacent (in time) fundamental particles. But I was thinking on the human scale. If we convert to the natural scale the gradients are so shallow as to be imperceptible. (The apparent rate of change is much, much slower than glacial.)

[I hope a real physicist will be able either to dismiss the argument that follows or else correct it or improve it.]

The number of protons in the Universe is estimated at about 10^80, matched by about 10^80 electrons, mostly in the form of hydrogen. Let us assume that each of these has, on average, changed quantum state N times in the approximately 13.70 billion year (4.3 x 10^16 seconds or ~10^60 Planck Units) duration of the observable Universe. This represents a gradient of N x 10^20 changes per hydrogen atom per natural unit of time for the lifetime of the universe. This would mean that the chance of any individual atom being in a different state between two adjacent time quanta is 10^20 x N/10^80 or N x 10^(-60). For any remotely plausible value of N, the Universe is now, on average, virtually static at the Planck scale. This reduces (but does not eliminate) the problem of continuity but raises a (perhaps more tractable) question of why the quantum state of an infinitesimally small proportion of atoms differ between adjacent time quanta.

No time quanta was detected in universe. The Einstein A coefficient explains the lifetime of atomic states as a reproducible time scale for the "atomic clock" : the most prcise and reliable instrument for time measurement available. The uncertainty principle in the optical resonator gives us another time scale for temporal measurement based on Fabry- Prot cavities. The femtosecond pulses generated in the mode locked Ti: Sa lasers may be the shortest sensible time scale that is reproducible, to my knowledge.

- Time is a measure of sequence to discriminate events without that all events occur simultaneously in space time.

- It is believed that a great number of events take place at any moment and this picture never happen again (physically) and therefore it is irreversible.

- The physical events including electronic excitations, vibrational and rotational modes of molecules are quantized while translational motion of particles in space-time exhibits a continuity that can be determined by time of flight measurements (TOF). Hence time is not discrete and resembles to be an unidirectional flow.

- to my knowledge, the shortest time duration is generated by femtosecond lasers and it is the minimum sensible time duration that can be measured presently.

I did not suggest that i was referring to "measurable" time units. The Planck unit is the "natural" unit of time and it is surely legitimate to consider gradients in terms of Planck units, whether or not they can be observed directly or measured experimentally and irrespective of whether the universe is quantised or continuous..

The absence of a flow of time is not an opinion, hypothesis or conjecture, it is an inescapable consequence of the ToR, whether we like it or not. Of course the ToR may turn out to be misconceived but all of its predictions so far have been verified within the limits of accuracy of measurements so we are rash if we reject one of its consequences without very good evidence.

The evidence of a physical fact is accredited by the measurements. TOR is an imperfect theory because no one could detect the spacetime curvature. To think of time flow, you have to measeure time durations as short as possible , then you need a real sensible time scale. According to the physics of resonator, time is a continuum as sort as fs intervals.

David

(Are you really called David David or is this a glitch of some kind?) I do not suggest that there is "no time" but only that time exists as a framework in which the intervals between events is recorded, just as space provides a framework for recording the separation of objects. The separation of objects may vary at different points in the time dimension. We exist for all of our lives but since "now" is defined by the physical state of our brains (our memories, hopes and expectations), every instant feels like "now". We cannot take today's brain back to an earlier time or forward to to later time so we have the impression that we are "trapped in the present". The point of my crude calculation of rates of change at the Planck scale was that every set of quantum states in one instant will be more probable than the same set in the previous instant. In other words entropy is the origin of "time's arrow".

Live animals, although their entropy may decrease from instant to instant are nevertheless inextricably entangled in the whole universe and so have the illusion of being carried forward on the wave of time.

These are only my own thoughts and cannot be tested. But "cause and effect" is an invention to account for the relationship between states of the \universe at wide separations (at the Planck scale) of time and proves nothing.

The Physics laws are based on four dimensions : xyz and t.

Corrections to sat-nav signals for relativistic time dilation, so that position is measured to within 1 meter rather 10-20 meters, assume that time dilation can be calculated to a degree of accuracy that is as fine as you like. The smallest measurable unit of time is irrelevant. Of course i agree that any prediction involving duration can only be directly tested at intervals greater than 1 fs (or whatever the current experimental limit is) but surely indirect tests can in principle measure any time interval that the experimental parameters allow.

If two objects are moving towards each other their world lines will converge - no flow of time is implied or required. Nevertheless, as I have written earlier, the time dimension is definitely not like the space dimensions. For example:

1. space is isotropic; time is anisotropic (the entropy gradient)

2. no object can occupy more than one spatial location at the same time but the separation of two objects in space can differ by Δx at an interval Δt providing that Δx/Δt

Stephen,

(David David was a glitch many years ago with which I now happily co-exist.)

I’m not positioned where I can track your framework with confidence or, in truth, understanding. But your thoughts feed my thinking and I appreciate this forum. I’m thinking “time” is a concept we have imagined and exported to the universe in the process of pursuing our existence. As such, it is probably a defining feature of our consciousness that has literally nothing to do with anything beyond that consciousness (which does not make it meaningless or non-useful). If that is the case, I’m trying to imagine implications. I also now think we have created other concepts such as “motion” and “thing/object” as well (probably before creating the “time” concept). Creating the concepts was not done with conscious “intent” as we normally think of it, but merely arose from our natural, evolving, mental processes.

Any dependent downstream concepts, such as entropy and space, among others, therefore, have been temporarily placed aside as intellectual tools to be referenced as I do or don’t make progress. My intuition is these concepts interfere with gaining understanding. I wouldn’t recommend this approach but I suspect it can be fruitful.

David

Docter is a surname in The Netherlands. Considerable amounts of time are wasted (or at least spent) resolving pleasing ambiguities with those who are medically qualified or have a PhD.

When you say "I’m not positioned where I can track your framework with confidence or, in truth, understanding" are you saying my explanation is confusing? If so, I'm sorry. It's always a risk when you are thinking in words (or aloud) and have to fight a tendency to digress.

Since I put the original question 5 months ago I have learned a lot, and clarified my own thoughts by reading others' comments and ideas.

My intuition is that String Theory, which has to be re-worked in any case now that the LHC has failed to show any trace of the particles that supersymmetry requires, needs to look carefully at the nature of time as a vital component of the Theory.

Stephen

Your explanations and questions educate, inform, and enrich me relentlessly. There is confusion, but it lies in my understanding - not your descriptions. My task is to unconfuse the confusions. As an aside, if no one digresses, I will make less rapid progress. I suspect sincere questions are best answered by sincere questioners. I, too, am learning and exploring - and I think that is among the points of ResearchGate.

1-Time is sensible using our biological clock =>a meaurable quantity.

2- Time is measured as accurate as 6 femtosecond using optics=>a real value.

3- Time is a physical dimension=> an indication of sequence of events.

4- If there is no time sequence, then all events in past, present and future happen simultaneously.

I agree that a time dimension exists and that it provides the framework for a sequence of events. I do not think, however, that a flow of time is either implied or required.

In time of flight (TOF) experiments using a fs laser and mass spectrometer, laser pulse causes coulomb explosion of the target molecules such that molecule disintegrates into several charged fragments. Then a short time interval is measured to determine the arrival of each fragment at a MCP to correlate the m/q ratio with TOF. MCP stands for multi channel plate at which a uniform electric field is applied to accelerate the fragments. For instance, the measurable fragments of CO2 are sorted after coulomb explosion in the following order: C+, O+, CO+, O2+ , C2+ and CO2++ and CO2+. This accredits the application of TOF in material identification.

Range finder is another example to attribute the TOF ( of a laser shot) with the round -trip distance covered by those photons . It indicates the use of TOF in distance assessment.

These instruments attests the measurable short intervals can reveal other physical properties.

Anyone who does not believe in reality of time should stop celebrating his/her birtdays.

Then, aging process is also not real. And the question who is older, father or son is irrelevant as well.

Alexander - I do not claim that "time does not exist" but that it exists as a timescape in which events and objects are located. Objects are different at different times and we define things as "older" or "younger" along the time dimension, so that birthdays occur at arbitrary intervals. I have been wondering, if time is quantised (see RG Question "Is time quantised?"), how the entropy gradient is formed and maintained? But in thinking about my response to you, it has occurred to me that the quantum states may be random but that we perceive them as a sequence because we define "now" by the state of our brain (memories and expectations). The world only makes sense to us if our brains present it to us as if it is an orderly sequence. In this case not only is the flow of time an illusion but so are the entropy gradient and cause-and-effect!

Not necessarily, Alexander, if reality of time turns on belief, as most do believe in and claim to experience eternity, the afterlife, and reincarnation or that we are not just our physical being, that we bear a consciousness, or the cyclic universe and all that is in it, or factually as in reverse physical aging: http://news.harvard.edu/gazette/story/2014/05/hope-for-aging-brains-skeletal-muscle/. Why do THESE foreboding BELIEFS persist, while comparable belief in yet a jolly gift-bearer named St. Nick (who actually existed) quickly goes by the wayside after a few Christmases?

Sure,Folks, in the case we discuss the afterlife, I would doubt existance of paradise, but insist on the reality of HELL. Evil deeds should be punished eternally.

And as eternety exist in time only, the time itself is the Reality.

But, why wear is not the same to all bodies, so for the same age one looks younger and another looks older? Probably it is the entropy of a system what really matters, who knows?

Demetris, the rate of aging is different for different bodies, so, people look different for the same age. Aging depends not only on time, but also on heredity and on the stile of live.

Alcoholic will look older, as he systematically poisons his body.

Dear Alexander

I agree with you. Aging and longevity depend on many parameters. Our biological clock is synchronized with solar clock and we really feel TIME. However, our habits, attitudes(stressful life,etc) and heredity strongly affect on aging. Despite, the biological clock is synchronized with the daily earth rotation, we may get older rapidly or slowly.

@Parviz and Alexander,

I´m following with interest your posts to aging. I think you are right, we feel the flow of time. But I have problems to accept that the daily earth rotation is determining our aging, daily sun cycle is determing the rhythms of humans. But did you ever think about birds life (1-2 years) or a special extreme example the day fly (ephemeroptera). It can´t impossibly be synchronized by daily repeating cycle.

Probably we have to exclude the biological time (the aging of our bodies) from the analysis, otherwise time will be proved to be correlated with our genes and will pass slower for people with better genes. So, lets examine other aspects of time.

@Demetris,

good and humorous proposal. I just follwed the idea, to connect our time feeling with earth rotation. I think time is independant from our perception.