The Arrow of Time? It’s All in Our Heads

By Robert Lanza, Wake Forest University | September 26, 2016 9:45 am


Have you ever wondered why we age and grow old?

In the movie “The Curious Case of Benjamin Button,” Brad Pitt springs into being as an elderly man and ages in reverse. 

To the bafflement of scientists, the fundamental laws of physics have no preference for a direction in time, and work just as well for events going forward or going backward in time.  Yet, in the real world, coffee cools and cars break down. No matter how many times you look in the mirror, you’ll never see yourself grow younger. But if the laws of physics are symmetric with respect to time, then why do we experience reality with the arrow of time strictly directed from the past to the future?

A new paper just published in Annalen der Physik — which published Albert Einstein’s theories of special and general relativity — Dmitry Podolsky, a theoretical physicist now working on aging at Harvard University, and I explain how the arrow of time ‒ indeed time itself ‒ is directly related to the nature of the observer (that is, us).

Our paper shows that time doesn’t just exist “out there” ticking away from past to future, but rather is an emergent property that depends on the observer’s ability to preserve information about experienced events.

Wave Function Collapse

The key to the nature of time is quantum gravity. During the last century, it became clear to physicists that the world of relativity (which deals with objects at large distances) and the world of quantum mechanics (which describes reality at small distances) are incompatible with each other. The problem of making them compatible, known in theoretical physics as the problem of “quantum gravity,” remains perhaps the largest unsolved mystery of science despite intensive efforts by some of the greatest minds of the century.

Cracking the puzzle of quantum gravity requires us to go back to the foundations of quantum mechanics, which remains as puzzling to students and experienced scientists as it was to Einstein over half-a-century ago. Perhaps the most puzzling feature among them is called “wave function collapse.”

To understand the problem, consider the light in your room. Common sense tells us that the light is either on or off, but not both at once. Yet, quantum mechanics allows such bizarre states (called “entangled”), in which the lights have been neither turned on or off. Instead, they exist in a “superposition” of the two states ‒ that is, both “on” and “off.”

Experiments confirm that entangled states exist at microscopic, scales, at the size of atoms or elementary particles. But if the laws of quantum mechanics are universal, why don’t we observe entangled states of macroscopic objects surrounding us? The famous Schrödinger’s cat experiment suggests that even cats and people can exist in an entangled state, i.e. they can be both “alive” and “dead” at the same time. If so, then why do real life cats always seem either dead or alive?

The answer, as was suggested by the founding fathers of quantum mechanics, is called “wave function collapse” or “decoherence.” The light becomes either permanently on or off – or Schrödinger’s cat alive or dead – if we, the observer, measure its state. When we measure the quantum state, we destroy its coherence.

The Arrow of Time Emerges

Einstein’s collaborator, John Wheeler (who coined the word “black hole”) argued that time itself emerges due to a decoherence of the wave function describing the universe, which is subject to the laws of quantum gravity. However, our paper shows that the intrinsic properties of quantum gravity and matter alone cannot explain the tremendous effectiveness of the emergence of time and the lack of quantum entanglement in our ordinary, everyday macroscopic world. Instead, it is necessary to include the properties of the observer, and in particular, the way we process and remember information. Our new paper suggests that the emergence of the arrow of time is related to the ability of observers to preserve information about experienced events.

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. Thus, many scientists question whether time even exists. Indeed, Einstein’s theories of relativity suggest not only that there is no single special present but that all moments are equally real.

So if the laws of physics should work just as well for events going forward or going backward in time, then why do we only experience growing older? All our scientific theories tell us that we should be able to experience the future just like we experience the past.

The answer is that we observers have memory and can only remember events which we have observed in the past. Quantum mechanical trajectories “future to past” are associated with erasing of memory, since any process which decreases entropy (decline in order) leads to the decrease of entanglement between our memory and observed events.  In other words, if we do experience the future (which we might), we are not able to store the memories about such processes. You can’t go back in time without this information being erased from your brain.  By contrast, if you experience the future by using the usual route “past > present > future,” you accumulate memories and entropy grows.

Thus, a “brainless” observer — that is, an observer without the ability to store observed events — does not experience time or a world in which we age.

Aging truly, is all in your head.

Robert Lanza is author of Biocentrism, and is a professor at Wake Forest University.  In 2014, Time magazine recognized him as one of the “100 Most Influential People in the World.” Prospect magazine named him one of the Top 50 “World Thinkers” in 2015. He is credited with several hundred publications and inventions, and over thirty scientific books. A former Fulbright Scholar, he studied with Nobel Laureates Gerald Edelman and Rodney Porter, and worked closely (and coauthored a series of papers) with noted Harvard psychologist B. F. Skinner and heart transplant pioneer Christiaan Barnard.

CATEGORIZED UNDER: Space & Physics, Top Posts
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  • joseph2237

    If you ask this author or most scientist what is Time they couldn’t answer you. Here then is my answer. Time is connected to Cosmic motion. Nothing in the universe stands still. The people on the East coast and West coast experience Time the same with the obvious exception of the position of the Sun and Time of day. A hundred thousand fans watch the Super Bowl at the stadium and millions watch on TV and many are doing different things. How does Time pass for all these people, the thing that is moving is the stadium because the Earth is rotating and following around the Sun. Time is tied to celestial motion throughout the cosmos. The Past is gone as soon as it arrive and in a separate place than the next second even though you haven’t moved an inch. The Past is gone and the Present is fleeting and the future is not a given for all of us.

  • John C

    As the author points out, quantum physics discovered that wave functions exist is all possible states until they encounter an aware observer. “Observer” is not defined in quantum theory – it can be an animate or inanimate entity such as a measuring instrument possessing some sort of “awareness” of its surrounding environment, the defining characteristic of consciousness.

    This is one of the most profound insights even made in science: In the case of a scientist observing a particle, his consciousness is not confined to the neural network of his brain; it affects the particle at a distance. Which leads one to conclude that consciousness is both non-local in that it is not confined within the observer, and also pervasive throughout a universe comprised of innumerable, variably aware “observers”.

    This raises the question of how consciousness and the neural
    network are related. Neurophysiologists explain consciousness as a result of the neurophysiological processes within the brain. Confined within the brain, they see consciousness being produced as an end result of neurological activity, coming to an end when the neurological activity ceases at death. Neurological activity is determined by the individual’s anatomy as well as disease states, drugs, etc. resulting in variable experiences of conscious awareness.

    This would make perfect sense is there were no evidence that consciousness extends beyond the cranium and neural network. However, the aware observer affects the wave function determining its final form, at a distance with no physical connection between the two. Matter at its most fundamental level is derivative from

    This key fact of the non-locality of consciousness opens up
    the interesting possibility that rather than simply being a generator of
    self-contained awareness, the brain might be actually more akin to an old fashioned radio receiver. In that view, the neural network enables reception of the general universal consciousness already existing outside the confines of the observer. The unique neurological anatomy and physiology of the observer enables specific individual awareness of universal consciousness the way radio circuitry tunes in to a specific frequency of the field of electromagnetic radiation surrounding it.

    Physical distortions of the neural network from disease, drugs or trauma will variously affect “reception”. More interestingly, people who are very attuned spiritually could be seen as having developed or been born
    with especially clear reception of the pervasive universal consciousness.
    Whatever theory turns out to be correct, neurophysiology must develop a new paradigm that accounts for the non-local effect of consciousness. This new paradigm will be remembered being as important as the insights of Copernicus and Einstein.

    • Prianka Imanudin

      This is an incredibly insightful response. I love how you connected the brain to an old fashioned radio receiver. It’s always been difficult for me to fully imagine how our individual brains interact with a greater universal consciousness that exists outside of our craniums. It’s a smart visualization!

    • Rixware

      In that context, the arrow of time looks more like a very clever means of isolating, for the benefit of consciousness, individual states of the universe which otherwise would be experienced as a cluster. If we had access to the whole of our life experiences simultaneously, making sense of any individual state (or “now”) would be virtually impossible.

      By simply cutting our ability to interact with and store information about a state of the universe into “now” slices, and allowing only limited (given the malleability of human memory) storage of those slices in one direction (which direction may not matter), nature has afforded us with a very powerful tool for parsing (experiencing) each individual state in a coherent fashion.

      In a way, that would be very similar to the purpose of our senses, which create both opportunities for, and limitations on, our ability to gather data about the universe, to be processed by consciousness.

    • joseph2237

      You seem to be a smart man but you have made a couple of critical spelling and grammar errors that make your post a little hard to follow. Sounds petty but it is the difference between being read or not. I think your view has merit and you should try to develop it. I do the same thing my self especially when I am thinking faster than I can type.

      Most scientist believe that there was nothing before the big bang and that it made time and space. Non-locality of consciousness could be better viewed as a two way radio than just a receiver because some people claimed to have developed the skill to use it when predicting future events like intuition, or knowing a thing before it happens. Consciousness out side the brain hints at a super consciousness and/or the possible existence of a creator. Not sure that would be a favorite idea of other science minded people.The arrow of Time is of course an observation that physical world can not be reversed and I would agree because the Past is lost in the motion of the planet and cosmos. The universe would keep on expanding with or, without mankind. Good luck.

      • Zhi Shan

        “Most scientist [sic]” don’t “believe” anything about what “there was …before the big bang and that it made time and space,” because a) we don’t have much evidence of what preceded the big bang and b) as St. Augustine observed, if the origin created space and time, then it’s impossible to discuss what was ‘before’ the big bang (and the origin of time), because ‘before’ assumes time. Never mind that some astronomers do think we have evidence of another universe preceding ours in the background radiation.

        Don’t you think you should clean up your grammar before attacking another’s grammar?

    • MDDanielss

      If our Universe is a 4D bubble on a canvas of higher dimension, we definitely would be able to feel it within our Universe one way or another. Remains to find that way.

    • John Deckenbach

      Well, that sounds lovely, but, the “observer” is NOT the human. Humans must use a photon detector of some sort to even detect the particle. Humans simply observe what the detector is detecting. If you tuned on the detector, the waveform collapse would happen even if no humans were watching. And humans can watch all day, and without the detector, no duality occurs. Your theory of non local consciousness is invalid.

  • iCeMediapro

    This Robert Lanza is a quack.

  • Disordered thinking

    I have a question about entropy. If the universe tends to disorder with the passage of time, it should follow that looking backwards in time the universe was highly ordered at the beginning of time-the moment of the Big Bang. In fact, it should follow that it was in it’s most-ever ordered state. My question is: what gave rise to that order? Can you get order without a ‘directing mind’ to organize things? Or is something as simple as gravity sufficient to provide order to the initial universe?

    • John C

      That is an interesting question. It takes an observer to collapse a wave function into discrete reality. What observer collapsed the original wave function into the original discrete reality, the big bang?

      • Disordered thinking

        So there wasn’t an original organizer, but rather an original observer?
        Interesting. What else can collapse a wave function, aside from observation?

  • Laszlo G Meszaros

    It is said here: “the fundamental laws of physics have no preference for a direction in time”. Well, this is one of the problems with these so-called fundamental laws.

  • Erik Bosma

    I think it’s just the way space works. As soon as you have 3 dimensions, movement becomes possible. Due to the way the 3rd D is associated to the other 2 (or perhaps because of a 4th) objects can only move one way in relation to the dimensions. Our brains also contain moving objects which are also in sync with the whole set of 3 D objects. Therefore, we can only observe time in one direction. If we could somehow observe our universe from a 4th D, we could observe stuff differently in time. I would guess jumping into a fair sized BH should do the trick.

  • LT_Armstrong

    Time clearly exists for one main reason: So we know
    how long it will be until lunchtime.

  • Eric_Stephens

    Dr. Lanza concludes “thus, a “brainless” observer — that is, an observer without the ability to store observed events — does not experience time or a world in which we age”. Isn’t this just another way of stating the dead (or unborn) do not experience time? Seems pretty obvious rather than profound.

  • David Burton

    The argument as presented here does not hold water. To be sure our conscious perception of time must involve memory. We must have memory of a past state to recognize a change in the present state. However the link from perception to existence presented is rather tenuous at best. Attempting to provide that link by invoking the role of the observer in quantum decoherence is a fallacy, though it is a commonly held philosophical position. Any interaction, no need for a conscious observer, can collapse the wavefunction. So we must separate our conscious perception of time from the status of its existence, or non-existence as the case may be.

  • Chris H

    we live in a decaying univers, I read that once and it summ it up.
    hypotheticly time can go either way, but it ever does. It alwasys progresses “into the future” as the great philosopher/human-nature observe & composer, Steve Miller put it.
    great read

  • microbooster

    What about CPT symmetry breaking? It’s been experimentally confirmed that CP breaking exists in specific kaon actions, and as you may know, breaking C or P implies breaking T as well.

    Also I think you put too much focus on “us”. Time passes for a stone just as well for a living thing. A stone is not aware of the passage of time (how could it be?) but if enough time passes, it will be eroded due to entropy increase (physical forces acting on it, thus increasing entorpy)

  • Brett A. Wheeler

    Time moves irrespective of the observer. Time moved before people born in the the 1980s existed and it will continue long after they are gone. The tree in the forest that falls without an observer will still emit sound waves. The laws of physics are not dependent on an observer. What we learn in quantum mechanics is that there can be several THEORETICAL (e.g. mathematical) possibilities, but that they exist only in theory. Just because we invent a state of matter based on the non-existent, imaginary square root of -1, doesn’t mean that it exists.

  • OWilson

    If it wasn’t for time, everything would happen at once.

    If it wasn’t for space, everything would happen in the same place.

    • ToMarsAndBeyond

      If there was no time, nothing would happen, also not at once.
      Happen is only there if time and space are there.

  • OWilson

    There is no absolute independent time, motion or space.

    It all depends on your frame of reference.

  • MDDanielss

    If so, why do we age at a constant rate? Why the true natural time rate could only be tied to the gravity? And why only this kind of a time “relativity” could be measured?

  • G Hall

    Could the arrow of time actually be created by the expansion of the universe ? What would time look like in a nonexpanding universe ?

    • ToMarsAndBeyond

      Good one. Time exists because of movement. No movement, no time. Easy. But does the universe expand? Or is it just our perception of it? We know sooooo little……

  • A.Alexander

    “Quantum gravity” I permanently hear this like ” halva halva” – so sweet, no more.

  • A.Alexander

    Arrow of time as I Prigogine `ve shown is the common feature of the mny particles systems: classical or quantum.This is the dissipation of the energy that makes these systems irrevercible in time. So any new discoveries in physics will confirm this arrow existance.

  • joseph2237

    Man who travels back in time will forever be locked into a vicious loop for which there is no escape.

    • ToMarsAndBeyond

      only if the future is set in stone. If the future is different each time you go back in time, than you might decide not to go back in time next time, haha.

  • joseph2237

    There really is no explanation for the arrow of Time. Time is an abstract that is and isn’t at the same time. There are only examples in which to visualize non-reversible events such as, cracked eggs, rain, water falls, car accidents, death, and earth quakes to name a few. To reverse Time you have to reverse the Earth, Moon, Sun and all the stars because that IS the only physical Time there is.

  • José E. Burgos

    The subjective nature of time is an old thesis that goes back to Kant (who also regarded space as equally subjective or “in our heads”). McTaggart revisited the thesis in his famous 1908 paper “The unreality of time.” More recently, Lee Smolin made an argument for the reality of time as key to achieve a theory of quantum gravity.

  • argz

    Robert Lanza MD is a doctor who is fascinated with Physics, as I am. Well, the Universe is such a strange place (we could be ‘holograms’ as in the Matrix’, as some physicist claim, but then who made the hologram?).
    Back in High School, I meditated and asked to see myself in 20 years and I dreamt I was hiking up mountain trails. I disregarded the dream, just having watched The Sound of Music for the nth time. But then, when I was actually hiking up the trails of Abra, I felt something like ‘de-ja-vou’. I’ve been here before, and then I recalled my dream and it just sync in. I was then a doctor trekking up mountains of the Cordillera.
    It is like there is somebody on a plane or balloon and he can see your boat is going to fall off a waterfall unless you stop and paddle to the shore and he was able to send the information to you.
    But the Arrow of Time is always forward in our experience. We may be given an inkling as to what will happen, but we cannot change the past. A broken glass cannot form itself anew whole.
    The 2nd Law of Thermodynamics or Entrophy supports this.
    Now, this new thesis will make our Universe awry, as if it isn’t awry right now (basing on our present knowledge of Physics).
    But, reading between the lines, there is no Past, Present and Future.
    It is like reading a book. when you start at page 1 and proceed, you will know the progression of time according to the story of the book. But the book itself contains the everything, what we may call past, present and future and it unfolds only when we read it. Thus, TIME, does not exist, it is all in the book reader’s mind. All the information is in the book, an eternal NOW or present. But we don’t know, and we’ll not experience the totality of the book at once, we have to go page by page.
    Dang, am I making sense to you???

  • amtonio carlos motta

    the spacetime of STR and Gravity são reality.the violation of PT and CP that implies the asymmetry of particles and antiparticles with torsion for the space due at the time Given by two curves,one orientable and non orientable surfaces.then for the quantum entanglements emerge the spacetime and that gives the arrow of flow of time,such for microscopic level while macroscospic level

  • amtonio carlos motta

    we could to think that the time is real and could be time asymmetrical
    às arrow of the flow of the time by the violation of symmetry PT that implies that the space and time be variable with the motion,it is with the increasing of the speed.i believe that time can To be measured by two dimension,being that the connection of space and time into of spacetime continues are symmetrical.the time is splitted in two dimension with torsion,it is left handed and right handed systems are asymmetrical as particles and antiparticles.then time curve the space in opposed orientation two,and the time dilatation and contraction of space are measured by the violation of CP that is linked the asymmetry between particles and antiparticles in high speeds nearest the speed of light,breaking the invariance of the lorentz’s orthochrous gripa ,only being renormalized in conjugation of the lorents antichrous groups.then the speed of light appear às Constant due the violation of symmetry PT.Then arrow of the flow of time is due the non existence of Antimatter,the antiparticles are asymmetries generated in the equations of STR and quantum gravity .the entropy appear as emerge of spacetime and gravity.the time and space there are in the physical world independente of our mind

  • amtonio carlos motta

    the possible violation of Pt and the non existence of antimatter would show a asymmetrical universe Ana the arrow of flow of time as something concrete.then the increase of entropy would explain an arrow for the time,só as the quantum gravity as the broke of GTR for beyond of the event horizon in the black holes

  • Wayde Leister

    As discussed in the ‘arrow of time’ an object, (human? atom? water molecule? ) not able to remember the past or the future, will always live in the present, oblivious to the facts. In the same way that even events unrelated to time, such as smart people having no way of knowing that they are smart until they encounter stupid people, and the wealthy not knowing they are rich until they encounter the poor, and vise-versa. In the same way, if there is no memory of the encounter, there is no knowledge / memory of the fact, but the fact remains the same. Time marches on whether we are aware of it or not, and although time is relative to our own motion, or lack of motion it can still be measured against the backdrop of things beyond our own perceived reality.

  • Aruna Pradhan

    What I understand is , Time doesn’t move .It’s Us ..physical. .observer. ..move .In other wards , It’s ” the consciousness ” that moves. I kinda getting addicted into Biocentrium. .good read. Thank you!

  • Robert Malone

    Beautiful article..I have the answer to Quantum Gravity
    Robert Malone

  • crankedyank

    A brainless observer does not experience anything and so can make no observations. His body would physically interact with the environment but this would not be an experience. My understanding of this interaction would represent a participation in a kind of collective observation. The problem with discussing consciousness n this way is that it is not a thing or substance that can be assigned locality (would it be made of something like phlogiston?) but rather a state of interrelatedness between components. But what is a component and what is just another thing? And so it goes.

  • Joe Cogan

    Thousand Island, or oil and vinegar, monsieur?

  • thinkdunson

    this article is complete bs. i wish reputable sources would stop pandering to the idiots who need confirmation that they’re special and important.
    “Our new paper suggests that the emergence of the arrow of time is related to the ability of observers to preserve information about experienced events.”
    this makes it sound all mysterious like it requires a human consciousness to observe, but the “observer” is anything that can preserve information about experienced events. like a loaf of bread getting old and moldy. or a comet flying through space shedding material as it experiences solar winds. no life, conscious or not, is required for time to exist.
    “Aging truly is all in your head.”
    just stop. you’re embarrassing yourselves and all of us, who call ourselves scientists.

  • astrosymbiosis

    The White Queen already understood this in 1865; “It’s a poor sort of memory that only works backwards,’ says the White Queen to Alice.” Lewis Carroll, Alice in Wonderland


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