• Brad Skow and the cover of

    Brad Skow and the cover of "Objective Becoming" (Oxford University Press)

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Does time pass?

Philosopher Brad Skow’s new book says it does — but not in the way you may think.

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“If you walk into a cocktail party and say, ‘I don’t believe that time passes,’ everyone’s going to think you’re completely insane,” says Brad Skow, an associate professor of philosophy at MIT.

He would know: Skow himself doesn’t believe time passes, at least not in the way we often describe it, through metaphorical descriptions in which we say, as he notes, “that time flows like a river, or we move through time the way a ship sails on the sea.”

Skow doesn’t believe time is ever in motion like this. In the first place, he says, time should be regarded as a dimension of spacetime, as relativity theory holds — so it does not pass by us in some way, because spacetime doesn’t. Instead, time is part of the uniform larger fabric of the universe, not something moving around inside it.

Now in a new book, “Objective Becoming,” published by Oxford University Press, Skow details this view, which philosophers call the “block universe” theory of time.

In one sense, the block universe theory seems unthreatening to our intuitions: When Skow says time does not pass, he does not believe that nothing ever happens. Events occur, people age, and so on. “Things change,” he agrees.

However, Skow believes that events do not sail past us and vanish forever; they just exist in different parts of spacetime. (Some physics students who learn to draw diagrams of spacetime may find this view of time intuitive.) Still, Skow’s view of time does lead to him to offer some slightly more unusual-sounding conclusions.

For instance: We exist in a “temporally scattered” condition, as he writes in the new book.

“The block universe theory says you’re spread out in time, something like the way you’re spread out in space,” Skow says. “We’re not located at a single time.”

Spotlighting the alternatives

In “Objective Becoming,” Skow aims to convince readers that things could hardly be otherwise. To do so, he spends much of the book considering competing ideas about time — the ones that assume time does pass, or move by us in some way. “I was interested in seeing what kind of view of the universe you would have if you took these metaphors about the passage of time very, very seriously,” Skow says.

In the end, Skow finds these alternatives lacking, including one fairly popular view known as “presentism,” which holds that only events and objects in the present can be said to exist — and that Skow thinks defies the physics of spacetime.

Skow is more impressed by an alternative idea called the “moving spotlight” theory, which may allow that the past and future exist on a par with the present. However, the theory holds, only one moment at a time is absolutely present, and that moment keeps changing, as if a spotlight were moving over it. This is also consistent with relativity, Skow thinks — but it still treats the present as being too distinct, as if the present were cut from different cloth than the rest of the universal fabric.

“I think the theory is fantastic,” Skow writes of the moving spotlight idea. “That is, I think it is a fantasy. But I also have a tremendous amount of sympathy for it.” After all, the moving spotlight idea does address our sense that there must be something special about the present.

“The best argument for the moving spotlight theory focuses on the seemingly incredible nature of what the block universe theory is saying about our experience in time,” Skow adds.

Still, he says, that argument ultimately “rests on a big confusion about what the block universe theory is saying. Even the block universe theory agrees that … the only experiences I’m having are the ones I’m having now in this room.” The experiences you had a year ago or 10 years ago are still just as real, Skow asserts; they’re just “inaccessible” because you are now in a different part of spacetime.

That may take a chunk of, well, time to digest. But by treating the past, present, and future as materially identical, the theory is consistent with the laws of physics as we understand them. And at MIT, that doesn’t sound insane at all.

Topics: Philosophy, SHASS, Humanities, Books and authors


Universe has no time

Now, I'd like to know more about how this theory addresses the nature of the future. Are all future events destined to happen? Or is the future yet to be written? It seems that quantum mechanics indicates that not everything is predictable, at least not with 100 percent certainty. How would this theory respond to the findings of quantum mechanics?

"The two most powerful warriors are patience and time" Toltsoy

Time is one day. It is our "measure" (as rod S was to Einstein).
We begin and end "our" day in the same place (raum).
In the meantime, we do as we please.

While no two objects can exist in the same space at the same moment, neither can different moments exist at the same time. L

No need of wormholes when we are apparently coexisting in the past present and future at once...I wonder how this can relate to shrondingers cat

I read Yourgrau's WORLD WITHOUT TIME and I think this book will be an excellent companion. I wonder if Skow will get all Heideggarian about "becoming". It sounds like it. I look forward to the read.

"moving spotlight" model looks very attractive, but the
notion of a light moving across the surface of space-time would
appear to require the existence of another time dimension with
respect to which this movement takes place. It is then easy to get
caught in an infinite series of observers and time dimensions. This
formed the basis of J W Dunne's "serial universe" model
(outlined in his book “An Experiment with Time”, published in
1927), which was rejected by most physicists.

This isn't exactly a new concept, is it?

Travelling along the cosmic way, past present and future, somewhere we will grab hold of Jimmy Saville, just remember!!!

Dudes! I wrote this same comment 2 years 2 months and 2 days from now.

Time, itself, is nothing more than a measurement of relative actions among everything that exists...... time has no mass, color, smell, it has no anything; it is a measurement.

Roger Yates' view of the need for another dimension seems convincing - unless Consciousness is outside the Universe altogether, on a Brane, for example. But how can we distinguish Skow's hypothesis from one in which the 'spotlight' shines on random moments in spacetime without order in any dimension? If 'my' spotlight was, 'a second ago', shining on a crab in Honolulu in 1987, and is 'about to' shine on a slug on Betelgeuse IV millennia from 'now' (or all at the same 'time', as seems implicit in the words of mystics), how would I know? I think his idea is interesting, and look forward to reading the book, but I think it might be, ultimately, an untestable hypothesis; naturally, I hope I am wrong, and he presents a watertight case - I would like to see this problem crossed off the list...

If all elements of the universe stopped moving, time would stop!
I prefer motion-time to space-time as a dimension!

If all elements of the universe stopped moving, time would stop!
I prefer motion-time to space-time as a dimension!

So, if past events still exist, however they are "inaccessible" because of our location in spacetime, then travelling backwards in time is possible if we can figure out how to relocate ourselves in spacetime. Easy, right?

Ancient Indian Texts say that there is no difference between past-present-future. It is ONE. The also add that differentiating TIME into past-present-future is the biggest disease of the mind. I believe that Time is another name of Love.

On page 155 of his book on the special and general theories Einstein
makes it clear that in general relativity, space-time no longer can
claim an existence independent of matter. On page 141 he said, “Our
concepts of space and time must be preceded by the concept of the
material object.” Almost everyone seems to have missed this. Time
does not exist, therefore, except as a concept of relative motion or
events relative to the motion of material objects, which we have
chosen the spin and orbit of Earth. Time is thus the relativity of
events. And events are separate realities. For instance, event 1:
the pitcher throws the ball; event 2: the ball arrives in range of
the batter; event 3: the batter swings and misses. But in this crazy
theory he cannot miss, because all events are coincidental, and I
wrote this comment at the same time as Dr. Skow wrote this nonsense!

This will help more: http://gsjournal.net/Science-J...

though the book would get number of readers worldwide but i afraid that theory would be accepted as 'block universe' or as time exist - past and future at same time. if i understood the correctly. 2nd, time could not be measured in term of universe as it is being assumed as a constantly expanding phenomena in all directions without knowing either time exist or not.

We experience time as a sequence of events and physics reduces this to measures of duration, as a measure from one event to the next. This then gets compared to measures of distance. Much as measuring the space between one wave and the next is similar to measuring the rate they pass a certain mark. Yet with distance, we are measuring an aspect of space, but with time we are measuring an effect of action. While we experience the sequence of events, the underlaying process is creating and dissolving those events. It is they which go from future to past. For example, the earth doesn't exist along some permanent narrative vector of day and we only seem to move from yesterday to tomorrow. Tomorrow becomes yesterday because the earth turns. The energy is conserved and the form changes. Probability precedes actuality.
Duration is the state of the present, as these marks form and dissolve.
As an effect of action, this makes time more like temperature, than space. Time is to temperature, what frequency is to amplitude. It is just that amplitude en masse is experienced as temperature, while frequency en masse is experienced as noise/static and so we extract one particular oscillation, spin, etc. and measure that. Be it rotations of the planet, or vibrations of a cesium atom. Yet just as temperature is a cumulative effect of lots of amplitudes, the passage of time is also a cumulative effect of lots of actions and the reason different clocks can run at different speeds is because they are different actions. In fact a faster clock will use energy quicker and so recede into the past faster. As with the twins in different frames.
One could use ideal gas laws to create the same relationship between measures of volume and temperature, or pressure, to create a measure of temperaturevolume, where constricting one raises the other proportionally, but since the scalar of temperature is not foundational to our logical functions, we can be more objective about it.
The problem is that what is creative problem solving to one generation, gets grandfathered in for the next generation and they take it as a given and go from there. Eventually the tide will turn and many of these premises will have to be reconsidered.

I think we, and MIT, should first try to understand the difference between a theory and a hypothesis before venturing into more complex matters like 'time'.

it has been posited (not by me) that a sentient/living creature in, say a 3-D universe would view/experience one 'moment' by another moment from a 'higher' dimension (in this case, the 4th) in a process we'd call "time" -- equivalently, a creature which lived in a 2-D (planar) realm would see one 2-d image/screen-shot(call it what you will) after another from the 3rd dimension. the positer (okay, I think it was Gurdjief (sp)) went on to speculate that one could view one 4-D 'moment' after another from the 5th dimension -- each 'higher' dimension is the time-component of the space-time continuum

It seems to me that we must always be living in the past! Whenever an event in the present happens, everything of mass has some kind of measurement of time before humans can receive that event. For example, sound travels at various speeds depending on density it's created, it travels faster in liquid, slower in oxygen, but regardless, it travels at some speed before being heard. Light travels at 186,000 miles per second before we can see it, or feel the heat from the suns rays which takes much longer then light for our senses to feel, but before we
can experience anything, and all of our senses can comprehend an event,
one's brain can only take in events as fast as the physics of the event can
travel. It may be a nano unit measurement of time we have yet to name, but it
is still the past. With that said, what we perceive as the present is actually
the past. Even if we could travel at the speed of light, we'd still be living
in the past, but moving faster into the future than those living in Earth's
standard time. Basically everyone living on Earth's standard time would only be
further in the past for those of us traveling at the speed of light, and though
those people traveling at the speed of light may age slower because they're
moving faster in time at the speed of light, they're still not experiencing living in their future, the physics of time limits still apply no matter how fast or slow one moves. So those moving at light speed still have to wait for information or events to
happen by the laws of physics! Therefore: time must be constant. Because there
are time limitations for all things, and the law of physics applies in
everything, then, now, and later, throughout our universe.

I'm late to the discussion, but I guess if time doesn't pass that's not a problem ... ;-) Seriously though, I'm always pleased to see some progress in this area and the discussion moving along.

With all due respect, however, I have a different understanding of time that comes from asking Einstein (metaphorically) "1) Can we travel through time at less than the speed of light - if so what does that look like, and 2) if we a travelling through the time dimension at the speed of light, what does that look like and aren't we in danger of hitting something (perhaps ourselves) coming the other way?".

My answers to these two questions expose problems with time as a dimension (I consider it a vector property of mass, not space, and not a dimension), and may be used to explain why quantum effects cut in at the atomic level. In short, we have carried pre Newtonian (ie prehistoric) ideas about time into relativity and quantum mechanics, whereas time is also relativistic and not everything goes through it at the speed of light. Fundamentally, in order to resolve the relativistic vs quantum dilemma a theory must be substantially in agreement with both, and my approach explains why both Einstein and Bohr are both right.

However, there cannot be enough different views on the subject and as JS Mill stated "The interests of truth are best served by a diversity of opinion." So keep on thinking, friend, "...and together we'll stand on the threshold of a dream." (Moody Blues)

The only thing we can be sure of timewise is where we are in time. We call it "now" and we can record which day and the time of day just as we can with regard to where we are - the location and its name. I am of the opinion that being conscious is essential for any idea about the passage of or the movement through time. First and importantly, we cannot say that time flows. If time flows past us as a river, then we are standing on a rock. What is this rock? The only sensible answer is, "me, here, now." But that is selfish, anthropic and different from anyone else's answer, so of course it's not a good answer. I doubt that anyone is standing on their rock in the river of time.
Next, it is obviously impossible to show that every conscious mind is experiencing the same "now". If the past, present and future always exist and make up Einstein's block universe, it makes no difference to my perception of meeting a friend on a Saturday night if she happens to be at work on the following Monday morning in her own mind. That last sentence should seem to you to be nonsense, and so it should, because the idea of "now" in a block universe is a purely subjective conception. It is meaningless to suggest that she and I were sharing a "now" moment. So long as her body was there when I was there to be conscious of it, then I experienced a perfectly normal Saturday night. The block universe contains that senario. We don't need to experience it subjectively simultaneously.
For me to wonder why I happen to be in the year 2015 right now, is as silly as my wondering why it isn't 1812 and I'm not Napoleon.
What I really want to say is that it's consciousness that is more the problem when we think about time, and what time is. Being conscious gives you a "now" and a "me". I doubt that there is a "Why" answer, and the "How" answer is probably unavailable to anyone, ever.
So let's go back to physics and toss out the philosophy. These questions like, "why does time go from past to future?" are silly questions. Ask a stupid question and you get a stupid answer. Einstein didn't have to ask those questions and I think he was right.

The block universe appears to follow almost inevitably from the geometric understanding of relativity, the interesting question that I think is being less well examined is how we can incorporate the absence of hard determinism which follows from the QM experiments in the style of Aspect which show there are no "hidden variables" and consequently measurements have a random element within the calculable probabilities. Much of the present philosophical work focuses on the implications of these for "local realism" but their impact on philosophies of time involving determinism is perhaps as significant.

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