The conscious experience of time may involve a 5th dimension
Time and consciousness are two phenomena that are integral to our experience of existence but neither is well understood.
Our subjective experience is that we are conscious of one moment at a time, which includes a basket of sense and mental phenomena. Thus, we feel that we are flowing from one moment to the next.
A cursory application of physics to time, however, raises questions about that position. If we are flowing from one moment to the next, then it suggests that different moments in time do not exist simultaneously. Instead, only now exists.
If that is true, however, it is difficult to incorporate Einstein’s theory of general relativity because it is, in general impossible to define a single parameter that we can call now. Instead, now flows differently at each position in space.
That does not imply, as some interpreters of relativity would have you believe, that time is an illusion or that Einstein believed it was. Rather, it simply means that time has a different structure, one that cannot be parameterized across the universe with a single clock.
The concept that certain events unambiguously precede others which we call causality is very much a feature of relativity. Hence, it is not so much that we can prove time an illusion as we can show that it is impossible, in some cases, to show that certain events took place before or after one another while in other cases it is possible.
For example, suppose I am on a spaceship and I have a laser that fires two beams of light in opposite directions, one forward and the other aft. I place mirrors at the front and back of the ship which will cause the light to bounce back. At the center I place a photosensitive detector which, if it receives a pulse of light from each direction simultaneously, will open a safe on board the ship.
If I try this, the safe will open.
Now, suppose the spaceship is traveling at a significant fraction of the speed of light with respect to my ship. If I observe the laser pulses travel from the center of the ship to the mirrors and back again from my ship, I will see the laser pulse going forward running to catch up with the detector at the forward part of the ship while the aft mirror will appear to be rushing to meet the laser pulse. The laser light itself, however, by Einstein’s relativity must travel at the speed of light in all frames of reference, so it is the same speed in my frame as in the frame of somebody aboard the ship.
From my perspective, therefore, the laser strikes the aft mirror first and the forward mirror later.
How then can I explain the fact that the safe opens?
Well, in order for the laser to open the safe, the light must travel the opposite direction as well. The detector at the center appears to rush up to meet the forward pulse returning to it while it appears to retreat from the aft pulse. All is well. They still strike the detector simultaneously in both my frame and the frame of the ship and open the safe.
This shows how simultaneous events can become non-simultaneous in another reference frame but not all simultaneous events become non-simultaneous in other frames.
This is just an example using special relativity, which does not take gravity into account. With gravity, you can have clocks running at different speeds depending on how close they are to a gravitating body like a star or planet.
Einstein’s relativity shows how the universe is most easily represented with a four dimensional spacetime where places in time are no different than places in space. Indeed, they are nearly interchangeable.
Even taking relativity into account, however, we can’t say what time is. We cannot even say whether the present is a special place or not.
Whether the past and future exist now or are being created and destroyed is a meaningless statement unless you could build a time machine and unambiguously travel to the past and future like the Doctor in Doctor Who. Traveling to the future alone isn’t meaningful unless you can get back to the past you came from since it could be that everything simply evolved there with you at a more rapid pace than usual. You had to have a closed loop.
Kurt Godel, a close friend of Einstein, attempted to tackle this problem and showed that Einstein’s equations could describe a universe that is rotating and allows for closed timelike loops, loops where one can travel back in time and return to the future point you started from. Godel was convinced that if you could travel backward and forward in time in a loop that disproved the so-called A-theory of time, that now, the present, was a special place. Instead, it was more like “here”. There is, in our concept of space, no special “here”. The universe doesn’t designate a particular place as special and so Godel thought why should it designate a particular time as special?
If this is true, then the universe is what we call a “block universe”.
Huw Price, author of Time’s Arrow and Archimedes’ Point, defines the block universe like this:
“the present has no special objective status, instead being perspectival in the way that the notion of here is. … there is no objective flow of time”
Thus, time is not an illusion in the block universe, only a special time, “now”, is illusory. All moments are now as all places are “here” in an objective, God’s eye view.
If we accept the block universe, then we are not forced to reject any concept of now, only concepts that are objective. For example, my consciousness could simply be flowing from one moment to the next, experiencing life with its own personal “now”.
That does cause you to wonder if the mind only inhabits the brain at one moment at a time are you, at the other moments, like a zombie?
For example, if I go on a round the world tour and visit many places, Buenos Aires, Capetown, Mumbai, Bangkok, Tokyo, and so on, each place is “here” for some amount of time, but, when I move on I am no longer there and some other place becomes here. What is left behind at the place I was were all the things I didn’t take with me: the buildings, the trees, the oceans, sand dunes, mountains, and so on.
If my conscious mind is like a traveler visiting each moment in a sequence, then the parts it doesn’t take with it from one moment to the next are left behind. That would be essentially everything: your body, your thoughts, and your feelings. All of those exist within specific moments of time and, when consciousness moves on, they are felt no more.
This traveling concept of the mind means that you have a non-corporeal intellect which visits each moment of your life, inhabiting the body, gaining sense impressions, and then moving on. It has its own internal concept of “now” but that concept may not be shared by other minds. The people with whom you interact, therefore, might be zombies. Their minds may have moved on to some other now although one would hope that is not true and that we would always interact with people when their conscious minds are there in their bodies.
An alternative viewpoint is that our consciousness is not dualistically separate from the body and brain at all but manifests from it. Material monism, the idea that all things that have existence are material, is one philosophical school that holds this to be true. In that case, consciousness has no personal “now” because it is everywhere the body exists.
In material monism, the mind is not like a traveler but more like a ladder. Each moment is a rung on the ladder. Every rung contains is own basket of sense impressions, thoughts, and feelings. The mind here encompasses the entire ladder but somehow creates the illusion that we exist within one moment at a time.
Since there is no flow of time and no objective or subjective now, we have the weird situation (at least weird to me) that we are effectively four dimensional beings who exist all at once. Our sense of flowing from past to future is actually an illusion created by the memories in our brains and other information growing phenomena.
It is like looking at a series of frames in a video, seeing them all simultaneously, and constructing the narrative in your mind, except that you are living that narrative.
In a dualist framework, this seems quite plausible. The non-corporeal mind could simply, upon encountering the material universe, generate within itself a narrative from the still frames of one’s life. It is the projector playing back the static film of the material world.
In a monistic framework, however, this doesn’t work. The first question that comes to mind is why we don’t experience multiple moments in time at the same time. Why does it feel like we only experience one moment at a time, in sequence? Even if this is an illusion, why can’t I experience myself now and also my 10th birthday at the same time. Why does it feel like I experienced my 10th birthday over 30 years ago and in between I experienced many other moments?
These are the passage and direction problems of time. Time appears to pass and it seems to move from past to future.
One potential explanation is that I am not experiencing my life at all. Instead, there are numerous copies of me, each of which experiences a single moment of my life. Each has only a moment of conscious existence and then dies while the next one is born.
In this case, there is no projector. Rather, you have lights shining through each frame of the projection rather than one light shining through each in turn. This is not surprising because the essence of this approach is to treat time, including consciousness, as if it is no different than space.
This explanation sounds very Zen to me but also doesn’t hold up to scrutiny. At best, it resolves the problem of why I don’t experience multiple moments of my life. It doesn’t not indicate how I have a sense of continuous existence. Rather, it says that sense of continuous existence is an illusion and that my sense of having been conscious of myself a moment ago is simply my memories giving me information about having been conscious. I have no way of knowing if I were actually conscious a few moments ago or if it was some copy of me.
A bigger problem with this concept of the block universe is one of sequence, i.e., passage of time and direction of time. I have the sense, not only of being conscious in this moment, but that I am experiencing each moment in sequence, one after another from past to future. Now, if it is true that I am only conscious at a single moment and there are many copies of consciousness, each experiencing different moments, then this too might be an illusion created by my memories.
The block universe does not quite fall apart here, but it makes me very skeptical to take away dynamical flow entirely. In addition, it doesn’t quite explain the most important part which is how can a static 4D reality generate consciousness in the first place?
The film demands a projector.
Silverstein, Stuckey, and McDevitt wrote a book on this problem. They argue that most popular accounts of time can’t explain conscious experience of its passage in objective terms, even if things really do change. They try to resolve this without resorting to dynamical evolution but also embrace dualism.
My own theory of time has evolved over many years. It starts with the universe as a five dimensional Anti-DeSitter space. You can imagine this as a set of disks (hyperbolic disks) stacked on top of one another to make a cylinder.
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