The Illusion of Time

[TimeTraveler1]

Time. We waste it, save it, kill it, make it. The world runs on it. Yet ask physicists what time actually is, and the answer might shock you: They have no idea. Even more surprising, the deep sense we have of time passing from present to past may be nothing more than an illusion. How can our understanding of something so familiar be so wrong? In search of answers,this video maybe help a bit

 

This gives a very proper idea of how time works, very interesting topic and quite a good documentary.

 

http://www.youtube.com/watch?v=yqzgYRBlslw

 

So the real question is....: How do we run out of something that doesn't exist?

please leave some comments and tell us your opinion about time.. is it really a mystery? or...?...

Also this is my first post here i just came i was searching for a forum like this! Nice to meet you all

Edited May 8, 2014 by hypervalent_iodine

[ajb]

Largely we don't care what time "is", but rather we want to mathematically describe it. Your question could be about almost any concept in physics. What is space or length or volume? What is energy or angular momentum? What is mass? What is a force? And so on...

 

To some extent no-one can tell you what they "are", the best we can really do is explain the mathematical concepts and state that they seem very useful in describing our Universe.

[swansont]

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Moderator Note

 

You need to do a bit more explaining and less relying on people watching a video that lasts almost an hour of time-as-we-know-it.

 

From rule 7: Links, pictures and videos in posts should be relevant to the discussion, and members should be able to participate in the discussion without clicking any links or watching any videos.

 

[`hýsøŕ]

time and space can both be treated as coordinates in some sense (thanks to relativity) so asking what time is is very similar to asking what space is. in that sense time is like a new direction of space which isn't physically visible to the eye but we're nevertheless travelling through it. as for asking 'no but really... what .. is it?' is a philosophical question which depends on your choice of definition of the word 'what' and 'is', which isn't necessarily the job of a physicist to answer.

 

(that's what i'd say if you ask me now, my answer'll probably be radically different in 5 years lol)

[milkybarkid]

Time is a differential between the ions of space and a human nature wishing to control everything that they come in contact with, Time as we know it, from milliseconds right up to billions of years, is a human invention. Time has no physical mass and never shall have, it is as a fairytale.

 

Alternatively.

Time could be described as from one point in space, to another point in space regardless of the seconds and hours etc that it takes to get between the two co-ordinates.

Edited June 6, 2014 by milkybarkid

[Mordred]

Time is a differential between the ions of space and a human nature wishing to control everything that they come in contact with, Time as we know it, from milliseconds right up to billions of years, is a human invention. Time has no physical mass and never shall have, it is as a fairytale.

 

Alternatively.

Time could be described as from one point in space, to another point in space regardless of the seconds and hours etc that it takes to get between the two co-ordinates.

time is simply a rate of change, you can have change that involves no change of space, depending on how you measure that change. Ie if you measure the time it takes for water going from solid to liquid, but if you measure the same process from the microscopic level you would see an overall change in volume. Depends on process your measuring.

 

I don't agree with your first statement, it is our perception of time that can change. The universe and time doesn't care how we perceive it. Time is simply a rate of change, I've always been amazed how everyone wants to place some greater meaning to time,( Arrow of time and entropy being one example).

 

Time is a rate of change in any and all possible processes

 

time dilation is simply a different rate of change, of the systems being observed or measured compared to events on your own relative time frame

Edited June 6, 2014 by Mordred

[studiot]

 

Time is a rate of change in any and all possible processes

 

Isn't that a tautology, especially since you posted it in two threads.

 

 

Mathematically can a variable be its own rate of change?

[Mordred]

not really its a definition, one could argue that due to relativity, processes have a measurable difference in how long it takes those events to happen. We call this a time dilation, but does it necessarily mean time itself changes, or does it simply mean the relativistic environment influences the processes involved. Sounds like semantics I know, but its an important consideration. Take the atomic clock experiment, did time change or did the energy exchange simply take longer due to the velocity? Time itself if there is such an entity other than being a unit of measure, isn't necessarily the only possible explanation for the difference in decay rates. Its just as plausible that the particles involved in the decay has an increased difficulty interacting with its environment. (probably not but it is possible)

 

The question really boils down to is does time necessarily have to have some hidden property, or can the effects of time dilation be explained via other processes such as rate of energy exchange vs environment?

 

by definition time is nothing more than the measure of rate of change, we simply do not know if time itself is the cause of time dilation, or if its due to other phenomena, ie particle interaction etc.

Its certainly simpler to define those changes in rates as a time dilation, that may or may not be the case though. One should never close the book on any theory regardless of how accurate that model is. We can only measure time by known process rates we cannot detect it directly

[studiot]

I was (politely) disagreeing with the statement "Time is rate of change".

 

Change is not necessary to time. It can proceed perfectly well without change.

 

Time is a variable, sufficient to distinguish between events or situations and to make predictions (in the sense of make deductions in accordance with physical laws) about them.

[Mordred]

ah no problem I can agree with that, evidently not the best way to define time lol

Edited June 6, 2014 by Mordred

[studiot]

I have a way of describing (the need for) time that might be better placed in the other current thread.

 

It describes a simple experiment with two bar magnets and a compass.

[jajrussel]

My current view of time is that time is as it is applied.

 

I can view an object in space and say that as a whole that time is the same for any point in, or on the object. All parts are in sync.

 

If I think dimensionally then time becomes part of a coordinate system that needs to be defined.

 

I can still view the object and think all parts are in sync, but I can now coordinate any point in or on the object with a reasonable degree of accuracy as defined by the coordinate system.

 

In order for another observer to agree with my findings a transformation may be necessary in order to satisfactorily explain the difference in observations.

 

I need to make a correction here. I cannot actually use a 4D coordinate system. I am still in the early learning process. I tend to think and write in the first person and forget what that implies sometimes, because I am too focused on my point. I did not mean to mislead.

Edited June 19, 2014 by jajrussel

[matterdoc]

'Cause and effect relation' gives us a sense of (flow of) time. Time is a functional entity that compares interval between two actions with respect to a reference interval (between two actions, interval between which is assumed constant). Time has no existence, except in minds of rational beings.

Nainan

[Curiousabout]

A billion light years from earth a star goes supernova, we observe this when the light waves reach us. Can it be said that the event just took place as far as our understanding of time? Does the event last forever relative to distance? What if there was another civilization a billion light years further from the event than we are? The information of the event would still be traveling through space time.

[Nicholas Kang]

So the real question is....: How do we run out of something that doesn't exist?

 

Largely we don't care what time "is", but rather we want to mathematically describe it. Your question could be about almost any concept in physics. What is space or length or volume? What is energy or angular momentum? What is mass? What is a force? And so on...

 

To some extent no-one can tell you what they "are", the best we can really do is explain the mathematical concepts and state that they seem very useful in describing our Universe.

 

This sounds like philosophy, not physics.

 

A billion light years from earth a star goes supernova, we observe this when the light waves reach us. Can it be said that the event just took place as far as our understanding of time? Does the event last forever relative to distance? What if there was another civilization a billion light years further from the event than we are? The information of the event would still be traveling through space time.

 

Time is relative, so do space according to Einstein`s Theory of Relativity. What we observe in deep space had happened far long ago because light travels at finite speed. For example, when we observe quasars. They don`t exist today but have become galaxies now. Yet, they help cosmologist in reconstructing the evolution of our universe.

[Curiousabout]

Physics or philosophy I’m not sure. My question and subsequent answers help me try to better understand. I was taught that anything that was dragged near a black hole would stretch and be ripped to pieces, and lost forever. Susskind questioned the issue of information being lost in hawking’s black hole. He explained that for instance a building is demolished, but that if you maintain all of the information about the structure that it can be duplicated. Therefore information is not lost. There are several theories of where information is stored and how it is retrieved from a black hole. If anything that enters a black hole is destroyed. What information could be retrieved no matter how it is stored? Isn’t it like taking all of the information about the building and running it through a super shredder. I ponder light and how it applies to information. I ponder light and the expanse of the universe and how it relates to information. And so I asked. A billion light years from earth a star goes supernova, we observe this when the light waves reach us. Can it be said that the event just took place as far as our understanding of time? Does the event last forever relative to distance? What if there was another civilization a billion light years further from the event than we are? The information of the event would still be traveling through space time. Does information travel in light infinitely?

Edited August 24, 2014 by Curiousabout

[Ophiolite]

I just wasted five minutes confirming my suspicion that the OP had plagiarised their opening paragraph, only to discover that a lot of time had passed since they posted it.

 

More on topic: my intellect is incapable of grasping the "meaning" of time. I suspect that is the beauty of a mathematical approach. It lets one deceive oneself into thinking one has grasped something fundamental.

[pears]

I was (politely) disagreeing with the statement "Time is rate of change".

 

Change is not necessary to time. It can proceed perfectly well without change.

 

Except that without change there would be no way to tell that time was 'proceeding'. Can time then actually be said to be 'proceeding' if there are no observers and no way to observe/measure the phenomenon?

[jibefan]

We live in a SPACE/TIME reality. Simply put, Time is "Movement" and space defines that movement.

[Tzurain]

Time is a relative, it's different for every person.

(Time is) The indefinite continued progress of existence and events in the past, present, and future regarded as a whole. - Dictionary

 

Having fun for 1 hour may feel like a minute, and having to hold onto a burning red coin for a second may feel like like an hour.

We have tried to measure time, and we have succeeded. The clock measures a second at a seemingly constant rate. But a second to each person is different to another.

I personally think the concept of time is something we can never grasp fully.

We live in a SPACE/TIME reality. Simply put, Time is "Movement" and space defines that movement.

It's nice to know you have tried to contribute, but there are many flaws in the sentence you have given.

What if you don't move at all? Does this mean Time has stopped?
If a person stands still in a cave, does the space he has moved (none) mean that no time has passed?

[jibefan]

if there is NO movement, there is no existence.

to answer your question more directly, if a person stands still in a cave, the atoms that make up his existence still have electrons MOVING around nuclei.

[swansont]

if a person stands still in a cave, the atoms that make up his existence still have electrons MOVING around nuclei.

Electron motion at the atomic level is not so clearly defined. There are no classical trajectories.

[andrewcellini]

if there is NO movement, there is no existence.

what does this have to do with time?

.

i'm not so sure of the validity of this statement either, but it seems to be philosophy more than physics.

Edited September 30, 2014 by andrewcellini

[Strange]

if there is NO movement, there is no existence.

 

Perhaps what you mean is, "if there is no existence then there is no movement".

[jibefan]

time began at the supposed "Big Bang" which I believe constituted the first movement in the universe.