Why is there a "now"?

[Vorpal]

But the read head analogy is fundamentally flawed. I'm asserting that there's no "tape" with the future or past always present, and no "read head" moving along it.

The analogy was only to link "now" to "here". In relativistic physics, it doesn't make sense, because the "now" of different observers can consist of entirely different events, even if they're co-located space. Because of that, relativity forces you to treat past, present, and future as equally real, and there doesn't seem any way around that except for solipsism.

The past is gone except for our memories, and the future is yet to exist. Just because we have ways to record, say, audio or video, doesn't mean the universe does anything similar.

You don't consider humans and video tapes to be part of the universe? The information of the past physical state is there in the present state, regardless of whether or not it is encoded in NTSC or PAL.

 

[BenBurch]

Does not follow down to quantum very well Ben
Try the Sci-am article....take with aspirin

Ah, but it does. You can define a cellular automaton with statistical rules.

 

[CplFerro]

Dear Zeph,

Coming from a Fremen point of view, there are two elements to the problem of what you Terrans call "time."

(1) The simultaneity of eternity, versus the temporal realm, and
(2) The opposition of positive and negative resources.

The individual human life, exists in eternity, but, being limited and associated with a body, doesn't act in eternity, but, in space. In other words, it is making eternal decisions in an apparent succession, which can only be imagined in terms of space.

The individual actually exists in the simultaneity of eternity, wherein all happens at once, in the "now," but, again, from the perspective of those living in space--in what you would term the "objective universe"--these happenings are separated by space.

Space exists as actual and potential, what Fremen term "the current," which the fish swims in. Actual and potential are both real and both present, and include one's own intention toward that particular space.

Negative resources equates with desire. Negative resources which impose themselves on the mind are termed adak.

Positive resources equates with memory. Positive resources which impose themselves on the mind are termed adab.

Both negative and positive resources are real, existing in space. Necessarily, negative resources clothe themselves in positive resources in order to direct the mind. One can intend toward either of them, becoming lost in them. Necessarily, both exist in terms of potential.

No one has been able to isolate this "time" of which is spoken of by Terrans, except in terms of space. There is the Current, which is actual, and also potential, which are positive and negative resources, which are real things existing on the horizon somewhere, quite often unavailable for comment.

Best, to remain in the current. Otherwise the fish dries out.

Yours,

"Cpl Ferro"

 

[case#46cw39]

Why is there a "now"?

because "past" has left the building and "future" has yet to arrive.

 

[Zeph]

My belief is the the universe possibly operates like a vast free-running (unclocked) cellular automaton. "now" is just the present state of the the automaton. As we can see change happen, and have memory of the previous state of the machine, we of course would see that as something like time.

So time travel becomes ridiculous as time is not a dimension, but a perception of change of state.

Hmmm. I'm trying to understand.

How does this belief system integrate with relativity? The analysis of the universe as four dimensional including time as a valid dimension has had quite a bit of explanatory and experimental success over the past century, and that is hard to so easily sweep under the carpet with one vague analogy, for me at least.

Does the non-clock on your unclocked automaton run slower close to the speed of light (or in a deep gravity field) for no reason, or do you have evidence to dispute special and general relativity? Is there even a meaning to "slower and faster" in your automaton, with no dimesions to compare; and how could you your belief system predict, calculate and measure the demonstrated time dilation of an orbiting satellite, without invoking time as a discrete dimension?

Zeph

 

[Zeph]

Why is there a "now"?

because "past" has left the building and "future" has yet to arrive.

Hi, case,

It's a cute analogy but not an acute analogy, and the former may be all you intended.

You are describing our subjective experience that there's a distinction between the past and the future with "now" as the joining point. We all (appear to) experience that, it's core to being conscious.

My question is about where in science there is any handle on there being such a special joining point. As far as I've seen, there is no concept of "now" in the physical universe of science, yet it's central to our consciousness - a huge discordance in our fullest knowledge of the world as I see it. You have rephrased one side of this disparity in a clever way, but not bridged it.

Some handle this disparity by discounting the subjective as illusory - the dimension of time exists as a whole from beginning to end with no special "now" cursor moving along it. Others take the opposite approach - in the subjective universe, only the now exists and the past, future and even time as a dimension must be illusions. Both of these can server to reduce a form of cognitive dissonance to comfortable levels. But I don't find either approach convincing in itself.

In my CD analogy, the former says "there is only the CD, there is no read head". And the latter says "the music being played now is the only reality, there is no CD".

We could segment time into "before 2pm last tuesday" and "after 2pm last tuesday" as well as "exactly 2pm last tuesday". But that point in time is no more special to the universe than 4pm last friday, or any other time - it's just an arbitrary and hypothetical point on an undistinguished continuum which is well understood in science. Why is the time you are reading this any different in any way from 2pm last Tuesday? Because it's your "now" - where the moving read head on your CD is located. But where in physics is that "read head" addressed in any way?

The closest I've seen to a direct answer is that MacDoc has referenced a more recent article in Scientific American in which I'm very interested; I'll be looking for a paper copy.

 

[Zeph]

Dear Zeph,

Coming from a Fremen point of view, there are two elements to the problem of what you Terrans call "time."

(1) The simultaneity of eternity, versus the temporal realm, and
(2) The opposition of positive and negative resources.

The individual human life, exists in eternity, but, being limited and associated with a body, doesn't act in eternity, but, in space. In other words, it is making eternal decisions in an apparent succession, which can only be imagined in terms of space.

The individual actually exists in the simultaneity of eternity, wherein all happens at once, in the "now," but, again, from the perspective of those living in space--in what you would term the "objective universe"--these happenings are separated by space.

Space exists as actual and potential, what Fremen term "the current," which the fish swims in. Actual and potential are both real and both present, and include one's own intention toward that particular space.

Negative resources equates with desire. Negative resources which impose themselves on the mind are termed adak.

Positive resources equates with memory. Positive resources which impose themselves on the mind are termed adab.

Both negative and positive resources are real, existing in space. Necessarily, negative resources clothe themselves in positive resources in order to direct the mind. One can intend toward either of them, becoming lost in them. Necessarily, both exist in terms of potential.

No one has been able to isolate this "time" of which is spoken of by Terrans, except in terms of space. There is the Current, which is actual, and also potential, which are positive and negative resources, which are real things existing on the horizon somewhere, quite often unavailable for comment.

Best, to remain in the current. Otherwise the fish dries out.

Yours,

"Cpl Ferro"

Dear Cpl Ferro,

Thank you for responding so kindly. I can only barely imagine the effort, and perhaps the analogs to what we terrestrials call "energy" or "resources", which must be involved in your translating the expression of the wisdom of your species, to the so limited linear symbols which we terrestrials use for communication, much less the illogical English language. I imagine the effort must be something like translating quantum physics into the location-of-nectar dances of terrestrial honey bees. I would like to complement you, as your sentences are generally grammatically correct, and the words are chosen from the lexicon of this period of linear human history, which is a remarkable achievement. We are still having some difficult extracting semantic content, but our best exo-cryptographers are still on the case.

Good luck with the fish, too.

Appreciations,
Zeph

 

[case#46cw39]

You are describing our subjective experience that there's a distinction between the past and the future with "now" as the joining point. We all (appear to) experience that, it's core to being conscious.

My question is about where in science there is any handle on there being such a special joining point. As far as I've seen, there is no concept of "now" in the physical universe of science, yet it's central to our consciousness - a huge discordance in our fullest knowledge of the world as I see it. You have rephrased one side of this disparity in a clever way, but not bridged it.

Hello, yeah I was just thinking of "the building" or stuff of the universe which we both see and feel. Then I was thinking (I don't know if science does) that this building itself is the link, which gives rise to time. The past is "that which is not in the building but was". The future is "that which has not yet arrived in the building". Yet the building is HERE, yet it is also not what it was in the past, so we needed a word for this state of affairs, and we called it ... NOW. LOL

 

[quarky]

zeph strikes me as sophisticated, and i want to be his friend.

I can fix bad plumbing and stuff.

But I'm no suck-up, so far.

 

[Mr. Scott]

Ah, but if there is no past or future how do you explain a photon from a past astronomical event that is on it's way toward Earth? When it reaches us we see the past event. Before it gets to us it has a future. After it leaves us it has a future somewhere else.

There are other examples besides a photon. It could be a loud sound heard 1,126 feet away (one second later). Or a letter mailed Monday and received on the other side of the world on Friday. Perhaps call it persistence of information. It's still just stuff moving around.

Then there is the twin paradox. If the twin travelling near the speed of light experiences time differently than the twin who is only moving at the speed of the Earth's rotation and orbit, then two different "nows" must exist. How else could those two "nows" end up out of sync with each other?

Instead of thinking it as time slowing down in the flying twin's spaceship, why not just think of it as all matter and energy moving slower within the spaceship, at a fixed rate for a fixed speed? There's a great thought experiment about this that pictures a light beam clock inside a spaceship, which counts time by bouncing a beam of light between two mirrors laterally to the ship's forward motion. If the ship is moving, the light traces a zig zag motion in space, and light being fixed in speed, has to make up that forward motion added to the lateral motion, so this clock must slow down, approaching zero as the ship approaches the speed of light (everything else in the spaceship would slowing for the same reason). Why do we need the abstraction of time as a spacial dimension to explain this? That just seems to confuse things.

What I'm trying to say is the time dimension, a useful abstraction for analysis, is not a spacial dimension we can move freely in like the first three, and treating it like it is causes unnecessary confusion.

 

[Mr. Scott]

No, I'm saying that we have a phenomenon that we call motion that we can only understand in the context of a dimension that we call time.

Given, that, the hypothesis that this dimension exists is the best one that we have.

To put it another way, time is an integral part of the way the laws of physics are framed. The simplest explanation for that is because it is real.

What you seem to be saying is that the past and future don't exist. That's true, but the past existed and the future will exist. And there's not anything particularly special about the present that I can see.

So I don't really see your point.

I think my point is, once we come up with words like, time, past, present, and future, and the analytic abstractions, it inspires fantasies that aren't helpful. For example, the read head analogy suggest the past, present, and future all exist at once and there's some read head moving through it. I've also heard the life of the universe as a movie film, with the future on the supply reel, and the past on the take-up reel, and the present in the film gate projected on the screen. What I object to is the idea that the history of the universe is physically stored somewhere (in the fourth dimension) and the present is a pointer moving through it. To use the movie projector analogy, there's no film moving through the "now" aperture. There's just a lot of stuff in the aperture (the 3 dimensional universe) moving around.

 

[sol invictus]

I think my point is, once we come up with words like, time, past, present, and future, and the analytic abstractions, it inspires fantasies that aren't helpful. For example, the read head analogy suggest the past, present, and future all exist at once and there's some read head moving through it. I've also heard the life of the universe as a movie film, with the future on the supply reel, and the past on the take-up reel, and the present in the film gate projected on the screen. What I object to is the idea that the history of the universe is physically stored somewhere (in the fourth dimension) and the present is a pointer moving through it. To use the movie projector analogy, there's no film moving through the "now" aperture. There's just a lot of stuff in the aperture (the 3 dimensional universe) moving around.

It's nice that you have that opinion, but that's not what physics says about time. Physics says that time is in fact a dimension, one that's different from the three space dimensions only in one specific way.

Not only does that not cause "unnecessary confusion", it makes it possible to understand a wide range of phenomena that would otherwise be totally incomprehensible - cosmological redshift, for example.

 

[schrodingasdawg]

To use the movie projector analogy, there's no film moving through the "now" aperture. There's just a lot of stuff in the aperture (the 3 dimensional universe) moving around.

There's an important point to be made that what events qualify as simultaneous depends on the frame of reference being used. So to say that only the present exists and that past and future are analytic abstractions requires also that only 'here' exists and that elsewhere is an analytic abstraction. (Otherwise, what is "now" - and thus what exists - varies between observers.) I wouldn't dismiss such a notion as completely absurd - I am somewhat sympathetic to certain forms of idealism - but I doubt such a view is very popular.

 

[Mr. Scott]

It's nice that you have that opinion, but that's not what physics says about time. Physics says that time is in fact a dimension, one that's different from the three space dimensions only in one specific way.

Not only does that not cause "unnecessary confusion", it makes it possible to understand a wide range of phenomena that would otherwise be totally incomprehensible - cosmological redshift, for example.

What specific way is it different? Why is cosmological redshift totally incomprehensible if we don't assign time a physical reality and just consider the universe to consist of stuff moving around?

 

[Mr. Scott]

There's an important point to be made that what events qualify as simultaneous depends on the frame of reference being used. So to say that only the present exists and that past and future are analytic abstractions requires also that only 'here' exists and that elsewhere is an analytic abstraction. (Otherwise, what is "now" - and thus what exists - varies between observers.) I wouldn't dismiss such a notion as completely absurd - I am somewhat sympathetic to certain forms of idealism - but I doubt such a view is very popular.

Ooops I smell argumentum ad populum.

I'm OK with "time" as a useful abstraction, but not as an assumed physical entity.

It's already acknowledged by time believers that there's at least one important difference between the time dimension and the first three, so I don't think saying there's only "now" leads to requiring there's only "here."

Why does this "require" that only "here" exists?

 

[BenBurch]

Hmmm. I'm trying to understand.

How does this belief system integrate with relativity? The analysis of the universe as four dimensional including time as a valid dimension has had quite a bit of explanatory and experimental success over the past century, and that is hard to so easily sweep under the carpet with one vague analogy, for me at least.

Does the non-clock on your unclocked automaton run slower close to the speed of light (or in a deep gravity field) for no reason, or do you have evidence to dispute special and general relativity? Is there even a meaning to "slower and faster" in your automaton, with no dimesions to compare; and how could you your belief system predict, calculate and measure the demonstrated time dilation of an orbiting satellite, without invoking time as a discrete dimension?

Zeph

The cellular automaton I hypothesize implements all the rules of GR.

The speed of light would be simply one of the rules it implements.

By "unclocked" I mean there is not a central clock that tells a cell to change state. "Free running" is another term for such a machine.

Could this ever be proven? Possibly not, though there may be things you can observe on very small scales that might hint at it.

That time can be successfully dealt with as a dimension does not mean that it must be one, and a hypothesis such as this shows how that can be.

One note is that this neatly explains the arrow of time as most non-trival cellular automatons are destructive of previous state.

 

[schrodingasdawg]

Ooops I smell argumentum ad populum.

I'm OK with "time" as a useful abstraction, but not as an assumed physical entity.

It's already acknowledged by time believers that there's at least one important difference between the time dimension and the first three, so I don't think saying there's only "now" leads to requiring there's only "here."

Why does this "require" that only "here" exists?

Because of the relativity of simultaneity.

According to me, a whole three-dimensional space is "now." There are other people who are observing the world during my now, and some of them may be moving with respect to me - perhaps at close-to-luminal speeds. According to such an observer, during my "now," a completely different three-dimensional space is "now." Our "nows" are not the same space. We have different presents. So if only the present exists, then what exists depends on the observer. Either that, or the entirety of the three-dimensional space besides "here" is an analytic construction just like time. (Or future and past exist just like elsewhere.)

I already explained this in my last post, but there's an elaboration.

 

[Roboramma]

There's just a lot of stuff in the aperture (the 3 dimensional universe) moving around.

But you still can't explain what "stuff... moving around" means without respect to time, so I don't understand how you think that you're doing away with the idea of time as a dimension.

 

[case#46cw39]

But you still can't explain what "stuff... moving around" means without respect to time, so I don't understand how you think that you're doing away with the idea of time as a dimension.

Every movement in what is "now", is "future" arriving, and "past" exiting, the building of stuff.

 

[Mr. Scott]

But you still can't explain what "stuff... moving around" means without respect to time, so I don't understand how you think that you're doing away with the idea of time as a dimension.

I'm just saying that when we PICTURE the time dimension as another physical dimension like the three spacial dimensions, it leads us to fallacious intuitive conclusions. The first three dimensions are identical to each other. The time dimension is fundamentally different, and too many people picture it as a fourth spacial dimension, and this is where the trouble starts.

When I say there is no physical thing we call time it's akin to saying that there's no universe computer that's performing calculus that moves matter through space. The stuff just moves the way it does because of the forces working upon it. We discovered (created?) the mathematics of motion, and we created the clocks and timelines to understand and measure time, but "time" as we understand it, just like calculus, is our invention imposed (usefully of course) on the universe.

FWIW I'm not sure the "ain't no time" hypothesis is correct, but it's interesting, so I'm advocating it to see where it leads. Prove it wrong.