The nature of time

Philosophy Forums Philosophy
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I apologize if this has been discussed before on this forum, I just did a quick search for “time” and no topics came up, so I’ll fire away with a question very close to my heart…

What is time?

As a physicist I often think long and deep about this question, and there are a number of opposing views coming into the mainstream right now (see September’s Scientific American: http://www.sciam.com/issue.cfm?issueDate=Sep-02)

Questions to be addressed:

Does time flow (from past to future), or does it just “exist” (whatever that means)?
Why can we remember the past but not the future?
What is “now”? Can it really be defined in any physical or philosophical sense?
Will it be ever possible to travel backwards in time?
Can we send/receive information through time without violating the laws of physics?
Is violation of the " Chronology Protection Conjecture " possible? Would anybody care if it were? Doesn’t “Many Worlds” (i.e. parallel universes) interpretation of quantum mechanics solve this problem rather neatly?

And here’s my own personal pet theory: the flow of time is really an illusion, evolved through natural selection to enhance survival.

I’d be interested to hear from any psychiatrists or medical doctors out there who have patients with diminished (or even reversed) perceptions of time, or who have radically altered rates of aging.

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most of the time stuff i think is on the science board.

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I thought I’d searched the whole database, just noticed someone had posted a similar topic under science, so I guess I hadn’t.

Anyway, I’m interested in a philosophical perspective on this question anyway, since many of the questions I’m posing would seem a bit outside the current abilities of scientists to answer anyway.

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Philosophically speaking, I see time as impulses of existence.

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This answer highlights one of the biggest difficulties in philosphizing about time. How to use natural language to describe our ideas.

How do you define “impulses” without a circular reference including time itself?

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Hi all,

This will be my first post. I’m from Sweden and I have tried to find good discussion boards in Swedish but so far I have not found any active. I realize that the ability to write good English is important when it comes to discuss philosophy and science, but I will do my best.

Time:

Time is a tool that is used to measure movement from one point to another in microcosmos or macrocosmos. Without movement there is no time. Without materia there is no time because the existence of materia IS movement. This is the reason why the universe is able to exist in a point zero. If the movement of all subatom-particles stops there is no longer materia. Time is always happening here and now; and everything that “existed” also exist now but in a different form (particles have changed position; have moved. If we reconstruct the previous positions of all particles that we include in the observation we have defeated time, and what we choose to call time does not exist. There is nothing moving more then the movement itself. This is the essence of time in my opinion.

Johan

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Like Johan, I believe time has to do with the movement of matter.

The animation of matter is what creates time. Meaning if there was no time, nothing could move. So this moving from A to B is not completed in an instance, but gradually (like Zeno’s Arrow). Time is measured by this gradual movement. Time might have always existed; but we are just at one point a long an infinite line stretching in one direction. (As I don’t believe we can go back through time, which I’ll get to in a minute… no pun intended)

But I would also add it’s not something that in itself has a reality. The reason why I think this, is because time changes depending on the speed of a moving matter. So it’s relative.

I also don’t believe in time travel, as it would require all matter to be made to move in its contrary direction. It would require the entire universe to implode back upon itself. The universe expands because of energy, caused we believe by the Big Bang. So to make the universe go backwards would require a similar force of energy to reverse the matter. Or you would have to figure out away to reverse the flow of energy. Meaning, if I throw a ball two meters and it lands on the ground, I have used up energy. Well to travel back in time, that ball would have to move from a stationary position on the ground back up into my hand. That would require the flow of energy to be reversed.

The next problem of travelling back in time is that of the person or thing going back has to be external to the rewinding of time. I believe going backwards in time would be the same as going forwards. Meaning if you remove something from the timeline (i.e. the object or person travelling back, which I’ll call ‘Traveller’) this would cause ripples in the system when travelling backwards. Because that Traveller is not there to be part of the whole rewinding process. So to rewind the system correctly the Traveller going back in time would also have to be rewind. But because the Traveller is still going forward in their own timeline (meaning the Traveller is creating new memory’s) while everybody else is having their memory reversed, that is, are losing memories. So the time you would travel back to is in fact a new time, which is different from the first time, because the Traveller was not apart of the rewinding of energy and interaction of matter.

But this is inconsequential; as I believe this whole reversal process is impossible.

Does time flow (from past to future), or does it just “exist” (whatever that means)?

I’d say it just exists in the expending of energy in the movement of matter.

Why can we remember the past but not the future?

Because we haven’t moved to that point yet. And since time is about movement, it’s simply because the movement that will create this new memory has not happened “or we haven’t moved to it” yet.

What is “now”? Can it really be defined in any physical or philosophical sense?

I see “Now” as the point at which movement is happing. The past are completed movements, the future are movements yet to happen. While “now” is the point where both meet but don’t touch, as there’s an infinitely small divide between the two.

Will it be ever possible to travel backwards in time?

I don’t think so.

Can we send/receive information through time without violating the laws of physics?

I Don’t know?

I hope that might have help?

Pax Vitae

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I want to start by saying that I have been away from the discussion forum for some time due to the inaccessibility of a computer to myself, which for all intents and purposes is a bummer. The earlier veterans of this site might remember me, but most of all I am pleased to see this area of cyberspace flourishing.

Time. What a concept! Defined by conventional means it would have to be our neurological impulses screened against this thing called a clock. As our minds are interpreting reality, the rate/entry of our stimuli can be measured with time. My friend Sally, who is right next to me expels “Hey!” at an exact time in reality, I receive this stimuli through my ears and process it slightly after the time she conceived of the idea of saying “Hey!” This would be a modern conventional means of defining time.

I don’t put alot of stock in conventional time. I think time has evolved in a specific way just like everything else has. I would be inclined to say that the moment of “now” is the sum of the stimuli and thoughts in our most immediate consciousness. When you say “right now” you simply think of everything that you are experiencing at this current point. I have experienced situations that would most invariably be opposed to the idea of conventional time. These experiences I would have to put in the category of telepathy. I think(not believe) that our minds are capable of connecting without a medium/stimulus which therefore allows us, in a way to communicate. Feeling another’s presence or intentions without them being in the room, and out of earshot is a prime example of how I think telepathy or the connectivity of our minds works. How does this relate to unconventional time? I don’t know… I just got lost on a rabbit trail.

The moment of “now” I think is a experience that maybe we could call a dream, and we are all just suspended in this huge and vast cosmic reality that has no previous time or future time, its just that we have this glitch in our brains called a memory and that gives way to the idea of past/present/future. I don’t know, I kinda lost my writing mojo.

I will end with the point that I think we know very little about time and how it applies to reality. Maybe we went wrong with this idea a long time ago in our evolution and are now in a very complicated mess, with might be countered with a very simple universal idea. Maybe?

I am pleased to be back commenting on all our fantastic ideas of the maybe and the what if. I send my regard to Thales, pangloss, as well as alex.

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If I had to think of one main characteristics that would seperate the modern view of time as thought by scientists from most philosophers (at least on the ‘continental’ tradition) is that many of the philosophers seem to give more weight to the mind in there being temporality. It is kinda like the origin of the universe, scientists propose the big bang, but that doesn’t really answer the metaphysical question…it just shifts the question. To say that time is measurement of events just shifts the question to how are such measurements or events possible in the first place? It would seem there has to be some temporaral flow that would serve as the ‘opening’ in which an event could happen…take away this structure, and it is hard to imagine there could be events. However, it is not that hard to imagine this opening without events.

Two the more interesting views of time are those of McTaggart and Heidegger. McTaggart denies the existence of time based on his argument against change. The argument goes basically like this. Time can be characterized either as a ‘before-after’ series or a ‘past-present-future’ series. If we can reject the former, the latter falls also (Russell denied the latter as substantial but retained the former). However, for there to be the ‘before-after’ series, there must be change…so really we want to reject change. So, McTaggart wants to show that nothing really changes. My reading of how he does this (from what I remember, it has been years since I read his essay so those in the know feel free to contribute) is based on the principle of idenity of indiscernables and the idea that what makes a thing be what it is are its properties. On the first note, given any thing in two hypothetical moments of time, if there has not been any change in properties, then there has been no change in the thing…so no change, no before-after. On the second note, if a thing has lost or gained a property, because it is the properties that make a thing what it is, then it doesn’t make sense to call the thing the same thing it was…so the former thing has not changed…we have a whole new thing altogether. For example x is {a, b, c} at t1 and at t2 we have x as (a, b, d} then it doesn’t make sense to call the object at t2 x. X has not changed…it no longer exists! and a new object exists. I think one could argue against this on the notion of accidental and necessary properties, but would have to deal with Quine’s argument purporting to show the arbitary nature of such accidental/necessary properties. What is significant about McTaggarts paper to me is that he shows that neither time nor change are necessary postulates to give an account of the world (as for example, Kant did). Although we might say that with something like physics and everyday life it is pragmatically convenient to use such notions.

I am not going to elaborate on Heidegger’s notion of time right now because it would take a good bit of writing, but will later if anyone is interested.

Trey