Accelerating Time: Examining the Link Between Space & Time

In summary, BoTemp thinks that time cannot be accelerated, and that any change in the value of time would only be recogniseable to us as a change in certain other aspects (probably the distortion in dimensions that were used to create the distortion in time).
  • #1
pete5383
85
0
Alright, so before I start off, I just want to say that I'm not very far into my physics career, but as I was reading on the forums here, I got to thinking about something...but, before I say my thoughts, I want to apologize if it's a stupid question. But here it goes:

So, I was reading on the relativity forums today about how space and time are linked, which I think understand (or, understand as much as anyone can). I was wondering something; there is a force on something if it is accelerating (F=ma). Time is going forward at 1 sec/sec at a constant rate (far as I know?). If time were accelerating somehow...not exactly sure, but if it were, would that apply a force? I mean...if time had a constant positive acceleartion throughout the universe, would everything in the universe be pushed backwards in time (equal and opposite reaction, and all)? So I guess what I'm asking is can time be dealt with the same way as a spatial dimention?

Sorry for maybe an odd question, but something that had been on my mind at work all day. Thank you!
 
Physics news on Phys.org
  • #2
I too am not all that knowledgeable in physics (high school knowledge at best, plus a bit of thinking), but as far as i can tell:

Time is just another dimension that can have various values. But since we are beings that base our existence on a certain continuity of time, it would be difficult to alter it (theory of relativity and all that).
*stops to think further on the question at hand*
Since i don't seem to be able to remember the exact theory on this, i'll have to goe with: any change in the value of time would only be recogniseable to us as a change in certain other aspects (probably the distortion in dimensions that were used to create the distortion in time).
So yes, kinda. We just don't know how to manipulate it in a way that we can see yet. And I'm probably wrong on this as well.
 
  • #3
I think maybe I can simplify the picture a bit. Time never ever changes. And by that I mean specifically that your wristwatch never ever changes.

Now, you may see other people's wristwatch slow down and even run backwards, but YOUR wristwatch will never change. Also you will never see anybody's wristwatch run faster than yours.
 
  • #4
No, I think see what he's getting at. In the three spatial dimensions we can apply a force (any force) to push things around. If time is another dimension, is there possibly some sort of force that can push things around in the time dimension?
 
  • #5
A time dimension is not the same as spatial dimensions. Relativity states that it's wrong to consider it as completely separate and independent, but time is different than space.

In regards to the wrist-watch remark, one will never see another persons watch moving backwards. Slower, or perhaps even stopped, but not backwards.

One of the most important consequences of relativity is that time is relative. One can talk about the passage of time of an event as observed by people at different velocities; one cannot talk about any inherent "speed of time". Take your body for instance; what would accelerating through time mean? Would you age faster? Faster relative to what? The only (theoretical) way to observe anything relating to the "speed of time", be it speed, acceleration, or any other derivative or integral relation, is relative to a different body.

In fact, this is what happens when a body is accelerated through space, or equivalently, under gravitational influnce. A stationary observer at infinity sees time slowing down for them.
 
  • #6
actionintegral said:
I think maybe I can simplify the picture a bit. Time never ever changes. And by that I mean specifically that your wristwatch never ever changes.

Now, you may see other people's wristwatch slow down and even run backwards, but YOUR wristwatch will never change. Also you will never see anybody's wristwatch run faster than yours.

ok, but i don't see that so obvious. inside a train that is accelerating, you don't see the things in the same room going at different velocities than yours, but you can tell that you're accelerating by the inertia force. Is the original question something like this?
actually, i can't imagine time accelerating, but if under some conditions, time was curved (stretched locally), yes, you should according to relativity experience some kind of " tidal force" reminding to inertia. Though i have difficulties imagining how it should feel :$
 
  • #7
BoTemp said:
In regards to the wrist-watch remark, one will never see another persons watch moving backwards. Slower, or perhaps even stopped, but not backwards.

Hi BoTemp,

Thanks for reading my post - I was referring to antiparticles whose proper time does indeed move backward according to Feynman's theory of positrons, which I believe.
 
  • #8
DaveC426913 said:
sort of force that can push things around in the time dimension?

Hi DaveC,

Your post is interesting, but I am having difficulty with it. Spacetime consists of EVENTS. Spacetime is not a container in which objects "move".
 
  • #9
This thread needs to be in special relativity
 
  • #10
Hey everyone. Thanks for the posts, and maybe my question was a little too...out there for there to be a definate answer.

I started thinking about this question when I was trying to understand time dilation. From what I understand, when an object is traveling at high speeds, it's length appears to be shortened (I think...right?) and it's time apparently slowed down. Since both is spatial and temporal dimensions were affected similarly by both being 'shortened' (I know, the time isn't really shorted, by slowed), I thought maybe there could be a force due to accelerating time the same as there would be a force due to something acclerating in the spatial dimensions.

Again, sorry for the weird question, but I just like thinking about things like that. :)
 
  • #11
pete5383 said:
Again, sorry for the weird question, but I just like thinking about things like that. :)

It is a good question. A lot of perplexity about relativity comes from people thinking about objects "moving" through time. Myself included.
 
  • #12
I think this a simple problem. Time is something relative to an observer: this observer defines what's a unit of time.

Accelerated movement can be considered as the acceleration of time. Let's say we consider our time absolute. Let's then consider an area of the universe where relatively to our time, the time deccelerates. Now imagine an object moving at the speed 1 m/s. Say the object reaches the area in question. In one of our second it would travel 1 m. If "their" seconds in that interval has a value of 1/2 relatively to ours, they would have seen the object travel faster, at a speed of 2 m/s. The next second, "their" value of a second is 1/4 and thus the speed of the object increases to 4 m/s.

As you can see, those "people" will see an acceleration of the object. When you talk about acceleration of time it has to be over another component. We could also consider "our own time" to accelerate relatively to an outside observer and realize how what he considers unaccelerated is accelerated to us.

Same can be said about accelerated movements instead of linears ones. I just took that example to avoid going into calculus.
 
  • #13
You almost had me, but then I realized if time was REALLY slowing in the "room of decelerating time" then any object entering that room would slow down as well!
 
  • #14
actionintegral said:
You almost had me, but then I realized if time was REALLY slowing in the "room of decelerating time" then any object entering that room would slow down as well!

I'm affraid I don't understand.. It all has to do with relative and absolute time. "Slowin down" wouldn't apply to an external observer. Time slowing down is just something that someone with an absolute time can define. Of course, the object itself would age less faster, but YOU will see it move at the same speed. The "area of slower time" is not relative to you anyway. It was just an example, instead of saying area you could just consider two persons, having different time flow.
 
Last edited:
  • #15
So let's say I'm sitting in my car, and I hit the gas, and start to accelerate in the X direction, with an accleration of Y m/s^2, there will be a force equal to mass*Y, and I will be pushed back into my seat with the same force (equal and opposite...I'm okay so far I hope. Been a while since school, haha).

Now, let's say I'm sitting in my car, and I have a velocity of zero. And let's say, somehow, next to my blinker, is a knob that speeds and slows the passage of time within my car (and before I get yelled at, I know this can't work like that, but I'm pretending. And maybe it's too much to pretend and ask for a real answer). So I turn the knob, and my time begins to speed up, (second derivative of time with respect to...um...time...d^2t/dt^2...hehe...hm...maybe not). Anyways, would I experience any type of reactionary force? I'm trying to ask this question and have it not relate to relativity, because I'm thinking about a non-relativity situation. I think...

I guess what I really want to know from my question is how much can we treat spatial dimensions and the time dimension the same? Can we look at it as just another spatial dimension, making four all together, along with X, Y, and Z, albeit a dimension that we (basically) only travely down one way at a (again, somewhat) constant velocity? Or do we have to distinguish that we have 3 spatial dimensions and 1 temporal dimension, because time is fundementally different from the others? Thanks again!
 
  • #16
actionintegral said:
Also you will never see anybody's wristwatch run faster than yours.

Ok, I surely don't understand time dilation very well at all, but how can this statement be justified. In the twins paradox the twin that accelerates away from the other, then returns to find more time has passed for the twin that didn't travel. Surely at some point along the journey the traveling twin has to notice that the non-traveling twins wrist watch is moving faster than his own. Otherwise how do you account for the non-traveling twins watch showing more time passed?

For this statement to be true, when the twins are reunited, they would have to show the exact same time passed on their watches.
 
  • #17
pete5383 said:
So let's say I'm sitting in my car, and I hit the gas, and start to accelerate in the X direction, with an accleration of Y m/s^2, there will be a force equal to mass*Y, and I will be pushed back into my seat with the same force (equal and opposite...I'm okay so far I hope. Been a while since school, haha).

Now, let's say I'm sitting in my car, and I have a velocity of zero. And let's say, somehow, next to my blinker, is a knob that speeds and slows the passage of time within my car (and before I get yelled at, I know this can't work like that, but I'm pretending. And maybe it's too much to pretend and ask for a real answer). So I turn the knob, and my time begins to speed up, (second derivative of time with respect to...um...time...d^2t/dt^2...hehe...hm...maybe not). Anyways, would I experience any type of reactionary force? I'm trying to ask this question and have it not relate to relativity, because I'm thinking about a non-relativity situation. I think...

I guess what I really want to know from my question is how much can we treat spatial dimensions and the time dimension the same? Can we look at it as just another spatial dimension, making four all together, along with X, Y, and Z, albeit a dimension that we (basically) only travely down one way at a (again, somewhat) constant velocity? Or do we have to distinguish that we have 3 spatial dimensions and 1 temporal dimension, because time is fundementally different from the others? Thanks again!

If what you mean is that someone outside the car will see a constant force and his time does not slow down, then as I was trying to explain, YOU will see it so that the force itself changes (meaning that the acceleration changes over time). You can't realize the slowing of your own time, because what is a second, is still a second for you. If what you mean is you see everything go slower, then the world's time and your brain's time are different. That is all.
 
  • #18
Werg22 said:
You have to realize that distance is absolute. A regular watch has a frequency of 1/3600 hz. It makes a rotation C. Both observers will see each other's watches rotate the same distance than their own. What changes is the value of time. One rotation might have took 1 second for one observer but 2 second for the other. That basically means that when 1 second elapses to one, 2s elapse to the other.

Maybe this makes sense and I am just too thick to understand. If Observer A (the one that leaves the Earth and returns) shows 10 years passed. And observer b shows that 20 years have passed (and both observers can see each others watch the whole time). How is it that when they are reunited (and both watches show different times have passed) that observer A never noticed observer B's watch to run faster than his, even though observer B's watch shows 20 years have passed compared to A's 10 years.

What it seems to me that you are saying (and I'm sure I'm wrong, but can't fathom why) is that the aging of each observer is independant of what their watch shows. But if both observers don't notice anything unusual in their aging compared to their own watch how can that be. I think it's agreed that when the two are reunited that one is physically older than the other, so if they both see each other the whole time, one sees the other aging faster. How else could there be a difference in their physical age if it wasn't so?
 
  • #19
A watch dosen't determine the flow of time! In fact the traveler will notice that his watch is faster than usual. Let's say during the travel the watches have made a rotation X. Both twins will see the watches spin the same, the difference is time duration they each witness. The traveler will in fact see his watch spin twice as faster as before. The watches will spin twice in a second instead of just once. Comparing again, the twin that stayed on Earth will see those two rotations as if they lasted two seconds.
 
  • #20
Werg22 said:
A watch dosen't determine the flow of time! In fact the traveler will notice that his watch is faster than usual. Let's say during the travel the watches have made a rotation X. Both twins will see the watches spin the same, the difference is time duration they each witness. The traveler will in fact see his watch spin twice as faster as before. The watches will spin twice in a second instead of just once. Comparing again, the twin that stayed on Earth will see those two rotations as if they lasted two seconds.

This is totally different than what I understood about time dilation so bare with me. The most common watch type today has quartz movement if I'm not mistaken. So let's say a quartz crystal occilates at rate R. Now human cell division (for lack of a better example) also happens at a determined rate, let's call it T. Here on Earth there is a relationship between these two rates that remains constant (cells division T happens at a given rate of R). Now somehow when we travel at some speed away from the Earth cell division no longer happens at the same rate of R? How is a quartz crystal's occilation period effected differently by acceleration than human cell division?

Also what you are saying seems to indicate that when the two watches in my previous post are reunited they will both show the same elapsed time (unless I totally missed the point), even though one person has physically aged more. How would this be possible when each observer sees the others watch running slow at some point, that when they are reunited they indicate the same time passed. Something has to speed up one of the watches to make up for the period the observer saw the other watch running slow. Again forgive my misconseptions, as I am having trouble understanding this.
 
  • #21
Werg22 said:
... In fact the traveler will notice that his watch is faster than usual. ... The traveler will in fact see his watch spin twice as faster as before. The watches will spin twice in a second instead of just once.

This is all completely wrong.

Werg22 has an erroneous understanding of time dilation. I have asked a moderator to step in and correct the error for GOD_AM's sake.

Apologies werg22, nothing personal.
 
Last edited:
  • #22
Werg22 said:
A watch dosen't determine the flow of time! In fact the traveler will notice that his watch is faster than usual. Let's say during the travel the watches have made a rotation X. Both twins will see the watches spin the same, the difference is time duration they each witness. The traveler will in fact see his watch spin twice as faster as before. The watches will spin twice in a second instead of just once. Comparing again, the twin that stayed on Earth will see those two rotations as if they lasted two seconds.

As has been mentioned, this is wrong.

A "traveller" does not see time in his inertial reference frame being ANY different. This is a common fallacy. Time dilation is only observed by an observer in an inertial frame of the time in ANOTHER moving inertial frame.

Zz.
 
  • #23
So are you saying that an observer will see the other watch spin differently than his?
 
  • #24
Yes. BOTH observers will see the other person's watch going slower.
 
  • #25
Werg22 said:
So are you saying that an observer will see the other watch spin differently than his?

If you are moving with respect to me, I see your clock moving slower than mine. You, on the other hand, will see MY clock moving slower than yours.

But I see nothing changing with my clock, and you see nothing changing with your clock. This is something that most people who have not understood SR often got wrong.

Zz.
 
  • #26
Zapper, if I'm moving with respect to you, won't I see your watch speed up? I could be wrong, but from what I understand of the twin paradox, wouldn't one watch have to speed up according to me.
 
  • #27
Remember, the twin paradox does not contain two INERTIAL reference frames. One of them necessarily has to accelerate - meaning special relativity does not apply.
 
  • #28
pete5383 said:
Zapper, if I'm moving with respect to you, won't I see your watch speed up? I could be wrong, but from what I understand of the twin paradox, wouldn't one watch have to speed up according to me.

And what about me? Do I see your watch slowing down? If this is true, and if we both are in inertial reference frames, then what makes my frame different than yours? You have then implied that one frame is more special than the other, because there is an asymmetry in here.

You simply cannot cite a "twin paradox" without describing in detail what is involved in the motion of the twins. Is it one stays in one frame, while the other accelerates, turn around, and comes back, or simply two twins in different inertial frames. You could be comparing something that are not identical. If you have a citation on where you read this "speeding up" part, I'd like to read it.

Zz.
 
  • #29
DaveC426913 said:
This is all completely wrong.

Werg22 has an erroneous understanding of time dilation. I have asked a moderator to step in and correct the error for GOD_AM's sake.

Apologies werg22, nothing personal.


Thanks for correcting this. I was wondering why no one else was helping in this thread, as it seemed to be contrary to everything I have learned here. I still have issues with the statement that one never sees the other's watch as running faster, and I'm pretty sure in the past I have read a post by one of the moderators that supported this view.

I will do some more thinking on this, and try to pose my questions again when I have cleared some of this out of my head.
 
  • #30
The question I would like to ask (once again as I don't think it has been answered yet) is concerning a situation where one twin remains on earth, and the other leaves the Earth at a high rate of speed, then returns.

In this situation it is my understanding that the twin that made the journey away from the earth, then returns, shows that less time has passed than the twin that stayed on the Earth when the two watches are compared side by side back on earth.

If both observers see the other's time passing slower than their own, how is it that when the watches are compared side by side back on Earth that the traveling twin now sees that more time has passed for his non traveling brother by comparison? If it's true that the rate of aging is consistant with the observers watch in their own frame then both twins always see their brother as younger than himself. Somewhere along the journey the traveling twin would have to see his brother as aging faster than himself, and see his brothers watch running faster than his own or how do we get this final difference in age back on earth?
 

1. What is the concept of accelerating time?

The concept of accelerating time refers to the idea that time can pass at different rates depending on the speed at which an object is moving. This is known as time dilation and is one of the key principles of Einstein's theory of relativity.

2. How does space affect the passage of time?

According to Einstein's theory of relativity, space and time are interconnected and can affect each other. The presence of massive objects, such as planets or stars, can cause distortions in the fabric of space-time, which can in turn affect the passage of time.

3. Can we observe the effects of time dilation in everyday life?

Yes, we can observe the effects of time dilation in everyday life, although they may be very small. For example, GPS satellites have to account for the time dilation caused by their high speeds in order to accurately calculate location and time for GPS devices on Earth.

4. Is it possible to travel through time by accelerating?

While accelerating can cause time dilation, it is currently not possible to travel through time in the traditional sense. The laws of physics do not allow for time travel in the way it is often portrayed in science fiction.

5. How does the theory of relativity impact our understanding of space and time?

The theory of relativity has greatly impacted our understanding of space and time by revealing that they are not separate entities, but rather interconnected aspects of the universe. This theory has also led to new insights and advancements in fields such as astrophysics and cosmology.

Similar threads

  • Mechanics
Replies
4
Views
600
Replies
11
Views
2K
Replies
8
Views
872
Replies
3
Views
717
Replies
24
Views
1K
  • Introductory Physics Homework Help
Replies
5
Views
974
Replies
1
Views
747
Replies
39
Views
13K
Replies
66
Views
3K
  • Special and General Relativity
Replies
11
Views
1K
Back
Top