Does time flow backwards of forwards?

[NWH]

Does time flow backwards or forwards?

If we watch a ticking clock we would come to the conclusion that time flows forwards because we see time progressing one tick at a time. One, two, three, four, time must flow forward because things change and progress from one state to another. We know for us time only flows in one direction, it doesn't switch it up and change its mind, what is done is done and it's irreversable. However if time flowed backwards the same would be true, things would change and progress from one state to another, four, three, two, one.

Say for example, if we were standing in the street on a windy day we would find millions of particles of gas whooshing past. In relativistic terms both us and the gas are moving, in one frame of reference we are moving through the stationary gas, however in another frame of reference the moving gas is whooshing past our stationary bodies. Can we apply the same comparisons to the flow of time as we do the flow of the wind? On one hand we observe time to progress forwards, but we our selves don't move backwards in time, we move forwards in time, so if we were to examine time relative to our frame of reference, wouldn't we conclude that time actually flows backwards instead of forwards? We and time couldn't be moving in the same direction because then time would be standing still, everything would be at rest, but we know that isn't the case. We have to flow through time just as time has to flow passed us in order for the universe to exist, otherwise we'd never get from A to B.

Us >>>>> Time
Time <<<<< Us

 

[PAllen]

If you really want to ponder the 'nature of time' in an informed way, a really good place is the following essays by leading physicists espousing every point of view imaginable - but with real physical insight and mathematics as a foundation:

http://fqxi.org/community/essay/winners/2008.1

 

[NWH]

We already know Relativity and Quantum Mechanics don't fit together, so surely a QM look at time is irrelevant here? Thanks for the link though, looks a good read!

 

[Drakkith]

Personally I just view time the same way I do distance. A measurement.

 

[NWH]

Personally I just view time the same way I do distance. A measurement.

But a measurement of distance has a direction in one of or all three dimensions of space, if you view them the same you must agree that a measurement of time has a direction also, surely not? The difference is we can move backwards and forwards across dimensions of space, we can not move backwards and forwards across the dimension of time.

 

[Drakkith]

But a measurement of distance has a direction in one of or all three dimensions of space, if you view them the same you must agree that a measurement of time has a direction also, surely not? The difference is we can move backwards and forwards across dimensions of space, we can not move backwards and forwards across the dimension of time.

Of course. But being simply a measurement, I don't see time as "flowing" or anything like that. At least not anymore than I see distance as flowing or whatever. FYI, we had a thread kind of like this one that was locked recently, so let's be careful on any speculation on what time "really" is or why we can or can't go backwards.

 

[NWH]

Of course. But being simply a measurement, I don't see time as "flowing" or anything like that. At least not anymore than I see distance as flowing or whatever. FYI, we had a thread kind of like this one that was locked recently, so let's be careful on any speculation on what time "really" is or why we can or can't go backwards.

Well, this thread is not to discuss about the nature of time, whether it exists or not, or whether we can go backwards or forwards, but whether time can be viewed in frames of reference like space can. We can say that one object is stationary in a system and that another object is in a state of motion, we can then use frames of reference to describe observations of events. Instead of using dimensions of space to describe an event, can we use dimensions of time to describe a moment? I hope you understand what I mean, I don't intend to turn this into a philisophical debate, I'm here solely to learn about Relativity, what it's able to describe and what its limits are, because I apply my own ideas to Relativity, I use it to think about thing you might not ordinarally think about, such as the direction of time. Whether those are scientifically backed I don't know, that's what I'm here to find out and I'm here to get people's opinions based on the facts that WE DO KNOW, not speculation.

 

[Drakkith]

Well, this thread is not to discuss about the nature of time, whether it exists or not, but whether time can be viewed in frames of reference like space can. We can say that one object is stationary in a system and that another object is in a state of motion, we can then use frames of reference to describe observations of events. Instead of using dimensions of space to describe an event, can we use dimensions of time to describe a moment? I hope you understand what I mean, I don't mean to turn this into a philidophical debate, I'm here solely to learn about Relativity, what it's able to describe and what its limits are.

A proper description of anything REQUIRES both spatial and time coordinates. Relativity allows us to calculate how far we are traveling in both space and time. Traveling very fast causes us to travel through time at a reduced rate, hence our clocks run slower at high velocities. (That's the short version anyways) And by travel I mean the difference in position in each dimension after multiple measurements. Usually we reduce the spatial movement to a single axis, which is relatively easy, just make your direction of travel your one spatial dimension you are actually moving in. This let's us graph spacetime on a 2d graph.

 

[NWH]

A proper description of anything REQUIRES both spatial and time coordinates. Relativity allows us to calculate how far we are traveling in both space and time. Traveling very fast causes us to travel through time at a reduced rate, hence our clocks run slower at high velocities. (That's the short version anyways) And by travel I mean the difference in position in each dimension after multiple measurements. Usually we reduce the spatial movement to a single axis, which is relatively easy, just make your direction of travel your one spatial dimension you are actually moving in. This let's us graph spacetime on a 2d graph.

Thanks. Something I think about is this. If I was to stand absolutely perfectly still, even though I'm not moving across dimensions of space, I'm still moving across the dimension of time, correct? Can I say that I moved across the dimension of time in one direction from moment A to moment B? Is this sort of concept backed by Relativity? Is this a question one might ask?

 

[ghwellsjr]

Well, this thread is not to discuss about the nature of time, whether it exists or not, or whether we can go backwards or forwards, but whether time can be viewed in frames of reference like space can. We can say that one object is stationary in a system and that another object is in a state of motion, we can then use frames of reference to describe observations of events. Instead of using dimensions of space to describe an event, can we use dimensions of time to describe a moment? I hope you understand what I mean, I don't intend to turn this into a philisophical debate, I'm here solely to learn about Relativity, what it's able to describe and what its limits are, because I apply my own ideas to Relativity, I use it to think about thing you might not ordinarally think about, such as the direction of time. Whether those are scientifically backed I don't know, that's what I'm here to find out and I'm here to get people's opinions based on the facts that WE DO KNOW, not speculation.

In Special Relativity, events already have a time dimension--and three space dimensions. If the time co-ordinate is constant for a set of events, then they define different places at the same time. If the three co-ordinates of space are constant for a set of events, then they define different moments in time at the same place. Your wish has already been granted.

 

[NWH]

So does SR agree that time has one fixed direction that we must obey, despite the varying measurements of time we experience?

Can I use a dimension of space to describe the dimension of time to get new answers to questions?

 

[ghwellsjr]

So does SR agree that time has one fixed direction that we must obey, despite the varying measurements of time we experience?

I suppose that since Einstein said time is what a clock measures and clocks run forward then SR agrees that time has one fixed direction. SR also affirms that time cannot stop which it would have to do before it could go backwards.

Can I use a dimension of space to describe the dimension of time to get new answers to questions?

Yes, if you mean some graphical method but you would have to test those answers to see if they comport with reality. And I don't believe that those questions couldn't also be answered by other purely mathematical means.

 

[NWH]

When I think of time I think of it like a river. I think of time as having a flow or a current to it which pushes against things that stand in its way.

So, if we were to imagine time as a spatial dimension, time would be a dimension in which I was in a constant state of motion, something that can speed up or slow down relative to other observers but something that can not stop. If we were to look at this from different frames of reference there are two observations we could make, A) I am in a state of motion or B) I am in a stationary state. Both answers are simultaneously correct, it just depends on whether we observe that I'm pushing against the river of time or that the river of time is pushing against me. Do you get what I'm saying?

Now, if SR says there is only one direction of time and that time can not stop, then can't we use this sort of thinking to determine the actual direction of travel relative to our passage through time?

I'm sorry if this goes beyond the realm of SR, but you never know without asking questions! If you could approach this with an open mind and imagine it from my point of view that would be great!

 

[ghwellsjr]

No one has any awareness that time is "flowing" any differently depending on their state of motion or acceleration or gravity or anything else. So I don't know why you would bother to make a statement regarding whether you are pushing against the river of time or the other way around. If anything, time just flows all the time identically for everyone. I don't think we need any additional conclusions from SR to affirm what we already knew about time, it just flows all the time identically for everyone.

 

[NWH]

No one has any awareness that time is "flowing" any differently depending on their state of motion or acceleration or gravity or anything else. So I don't know why you would bother to make a statement regarding whether you are pushing against the river of time or the other way around. If anything, time just flows all the time identically for everyone. I don't think we need any additional conclusions from SR to affirm what we already knew about time, it just flows all the time identically for everyone.

I thought it was light that was constant, not time. :/ We do have an awareness of time flowing differently because we can communicate with each other to confirm those differences.

 

[ghwellsjr]

No one has any awareness that time is "flowing" any differently depending on their state of motion or acceleration or gravity or anything else. So I don't know why you would bother to make a statement regarding whether you are pushing against the river of time or the other way around. If anything, time just flows all the time identically for everyone. I don't think we need any additional conclusions from SR to affirm what we already knew about time, it just flows all the time identically for everyone.

I thought it was light that was constant, not time. :/ We do have an awareness of time flowing differently because we can communicate with each other to confirm those differences.

I was talking about your idea of pushing against time or time pushing against you. It never changes for you. Even when we communicate with each other and measure the other guy's clock and time as running slow, we don't perceive any difference in the "flow" of time for ourselves. It's only for the other guy. And he can't perceive any difference either, he's saying we are the ones that are affected.

 

[NWH]

Well I think all my questions have been answered, thanks! But before I finish I want to (and can) elaborate on this analogy of the flowing river of time to explain time dilation.

Imagine we have a flow of water down a stream that flows from north to south at a constant and uniform rate, and in that water we have two sticks with detectors on which tick a hand of a clock each time a particle of water brushes past the detector. Since both sticks are stationary an equal amount of water particles brush past the detectors and the hands of the clocks tick at the exact same rate. Now let's imagine one of the sticks starts to slowly move south in the direction of the current, suddenly the stick which is in motion is stimulated at a slightly slower rate than the other stick since the detector is moving in the same direction as the particles of water, suddenly the hand of the moving clock ticks slightly slower than that of the stationary clock, this is because the flow of water (time) interacts differently with the stick in motion than it does with the stick that is stationary.

To me time is like a river that flows and pushes against us, and how we move in that river changes our measurements and determines our passage through time.

 

[ghwellsjr]

The problem with your analogy is that it would imply that time dilation is linear with the speed of the stick, correct? So if the stick were moving at 1% of the speed of the river, the time dilation would cause a clock to run at 99% of normal, correct? But the relationship of tick rate to the speed of light is not linear. For the same 1% of the speed of light, a clock will run at 99.995% of normal

 

[NWH]

The problem with your analogy is that it would imply that time dilation is linear with the speed of the stick, correct? So if the stick were moving at 1% of the speed of the river, the time dilation would cause a clock to run at 99% of normal, correct? But the relationship of tick rate to the speed of light is not linear. For the same 1% of the speed of light, a clock will run at 99.995% of normal

Indeed, although the faster we travel the greater the effects of time dilation right? If we could travel 100% the speed of light the ticking of the clocks would be 0%, that would be the equivalent of the stick breaking free and just floating on the surface of the water, because there would be no more resistance and time would cease to exist... I know this doesn't have much mathamatical value and I guess that expresses the limits of my capabilities, but it paints a nice picture. I can't help but view time in this way, I can accept the notion that time is just a measurement, but changes in measurements that are verified by experiments must be part of some strange quantum phenomenon and I look forward to the day we understand it better.

 

[yuiop]

The problem with your analogy is that it would imply that time dilation is linear with the speed of the stick, correct?

Why would it have to be a linear relationship? For example the force on a stationary object when air is flowing past it is proportional to the square of the wind speed.

 

[ghwellsjr]

Indeed, although the faster we travel the greater the effects of time dilation right? If we could travel 100% the speed of light the ticking of the clocks would be 0%, that would be the equivalent of the stick breaking free and just floating on the surface of the water, because there would be no more resistance and time would cease to exist... I know this doesn't have much mathamatical value and I guess that expresses the limits of my capabilities, but it paints a nice picture. I can't help but view time in this way, I can accept the notion that time is just a measurement, but changes in measurements that are verified by experiments must be part of some strange quantum phenomenon and I look forward to the day we understand it better.

But since no massive object, including all clocks, can travel at the speed of light, there is no conclusion that you can say applies, such as the ticking of clocks would be 0%. It's not that time ceases to exist at lightspeed, rather you should think of time as being what a clock measures and since no clock can travel at the speed of light, there is no meaning to the concept of time at the speed of light. It would be like having an understanding of color being the wavelength of light and then asking what color is darkness. If someone said, well if darkness had a wavelength what would it be, you wouldn't try to answer the question, would you? Wouldn't you rather point out that the question doesn't mean anything? The concept doesn't apply. That's why I object to your statement, "If we could travel 100% the speed of light the ticking of the clocks would be 0%".

 

[ghwellsjr]

Why would it have to be a linear relationship? For example the force on a stationary object when air is flowing past it is proportional to the square of the wind speed.

Well, apparently NWH thinks it is something like a linear relationship because when you get "close" to the speed of light, it's just one more small step to reach it, instead of realizing that no matter how fast you are flowing in the river, the speed of light remains just as far away, it's just like you haven't changed at all from your starting point.

 

[NWH]

Of course this is just an analogy to explain a concept, not an experiment devised to prove the existence of time as an actual force.

 

[ghwellsjr]

Of course this is just an analogy to explain a concept, not an experiment devised to prove the existence of time as an actual force.

In nature and in Special Relativity, time dilation is reciprocal between two observers. That is fundamentally important. How does your analogy explain that?

 

[Whovian]

We already know Relativity and Quantum Mechanics don't fit together, so surely a QM look at time is irrelevant here? Thanks for the link though, looks a good read!

We've actually formulated a quite decent set of theories that puts Quantum Mechanics and Special Relativity together.

 

[Whovian]

In nature and in Special Relativity, time dilation is reciprocal between two observers. That is fundamentally important. How does your analogy explain that?

Remind me what that means. Observer A should "think" observer B's clock is running slowly, and observer B should see observer A's reference frame dilated by the same amount. Is this what you mean?

 

[yuiop]

Well, apparently NWH thinks it is something like a linear relationship because when you get "close" to the speed of light, it's just one more small step to reach it, instead of realizing that no matter how fast you are flowing in the river, the speed of light remains just as far away, it's just like you haven't changed at all from your starting point.

OK, I see your point now. Another problem with the flowing time analogy is that implies you could move in the opposite direction to the flow and speed up your clock rate, which is not observed in nature either.

 

[ghwellsjr]

In nature and in Special Relativity, time dilation is reciprocal between two observers. That is fundamentally important. How does your analogy explain that?

Remind me what that means. Observer A should "think" observer B's clock is running slowly, and observer B should see observer A's reference frame dilated by the same amount. Is this what you mean?

It means that there is no difference between observer A and observer B. Both observer A and observer B measure the other ones clock as running slower than their own. There is no reason to say that only A "thinks" that B's clock is running slower while only B "sees" A's clock as running slower. Whatever the experience, observations, determinations, conclusions, etc of one of them is, the other one has exactly the same experience, observations, determinations, conclusions, etc. This is assuming that both observers are inertial.

 

[Whovian]

It means that there is no difference between observer A and observer B. Both observer A and observer B measure the other ones clock as running slower than their own. There is no reason to say that only A "thinks" that B's clock is running slower while only B "sees" A's clock as running slower. Whatever the experience, observations, determinations, conclusions, etc of one of them is, the other one has exactly the same experience, observations, determinations, conclusions, etc. This is assuming that both observers are inertial.

Exactly what I was saying, I just phrased it badly.

 

[ghwellsjr]

OK, I see your point now. Another problem with the flowing time analogy is that implies you could move in the opposite direction to the flow and speed up your clock rate, which is not observed in nature either.

Well, I think the whole idea of NWH's analogy is that the sticks are anchored to the bottom of the river bed and have no means of propulsion on their own but as the anchor slips, they can move down stream by the force of the river. In post #19, he talked about a stick breaking free and just floating on the surface of the water. So there would be no means for a stick to flow upstream. Sorry.

 

[nitsuj]

If we watch a ticking clock we would come to the conclusion that time flows forwards because we see time progressing one tick at a time. One, two, three, four, time must flow forward because things change and progress from one state to another.

I think this can be answered simply with causality.

The cause is always before the effect.

It isn't a deep understanding of time that explains this "direction". At least I don't think so, it's merely considering that the above is always true. I think time itself is a slightly different subject to this forward/backward flow "concept".

 

[yuiop]

One curious aspect of the flow of time is that in a completely deterministic universe, if the flow of time was suddenly reversed, we would be completely unaware of it. The chemical and biological processes in our neurons that form our memories and any other physical processes that provide evidence of what has happened are also reversed, so we have no recollection of the future that has "already happened".

 

[Drakkith]

One curious aspect of the flow of time is that in a completely deterministic universe, if the flow of time was suddenly reversed, we would be completely unaware of it. The chemical and biological processes in our neurons that form our memories and any other physical processes that provide evidence of what has happened are also reversed, so we have no recollection of the future that has "already happened".

That's assuming a "time reversal" actually causes all processes in the universe to proceed backwards. Assuming that time doesn't "flow" and it's just another dimension that we measure, would we even notice a difference? But perhaps that's too much speculation...

 

[Whovian]

Assuming that time doesn't "flow" and it's just another dimension that we measure, would we even notice a difference?

Yea, that's one of the reasons I think of time as, well, just another dimension, with slightly different properties. For example, say time stops temporarily. No one's going to notice, since the mental processes that allow them to notice things also stopped. There's going to be no way to verify whether or not it stopped. Something similar probably goes for time going backwards.

 

[ghwellsjr]

Yea, that's one of the reasons I think of time as, well, just another dimension, with slightly different properties. For example, say time stops temporarily. No one's going to notice, since the mental processes that allow them to notice things also stopped. There's going to be no way to verify whether or not it stopped. Something similar probably goes for time going backwards.

My laptop has the ability to run at different speeds (to prolong battery life). The programs running on it don't know what speed they are running at. I can even put the laptop in standby and bring the programs to a halt, which they are also completely unaware. Then when I power up the laptop again, the programs pick up where they left off and again, they are unaware and produce exactly the same results as if I had never slowed or stopped the system. But I cannot make the laptop run backwards. That doesn't make any sense. There is no way that anyone can construct a computer that allows programs to run backwards.

The idea of time running backwards comes from the fact that our laws of physics that involve time produce solutions in which the time variable could go in either direction. But like many other mathematical representations that can produce more than one result, we have to discard the ones that don't make sense.

There are many discussions about the flow of time but when Einstein made the simple definition that time is what a clock measures and since all clocks run forward, there is no place in the context of Special Relativity to be speculating about time stopping or going backwards.

 

[Whovian]

My laptop has the ability to run at different speeds (to prolong battery life). The programs running on it don't know what speed they are running at. I can even put the laptop in standby and bring the programs to a halt, which they are also completely unaware. Then when I power up the laptop again, the programs pick up where they left off and again, they are unaware and produce exactly the same results as if I had never slowed or stopped the system. But I cannot make the laptop run backwards. That doesn't make any sense. There is no way that anyone can construct a computer that allows programs to run backwards.

I never said that. You may have been misinterpreting what I was saying. Sort of what I was arguing is that time flowing backwards wouldn't even have any meaning, since it wouldn't be verifiable at all. May have phrased that badly, I'm always doing that.

There are many discussions about the flow of time but when Einstein made the simple definition that time is what a clock measures and since all clocks run forward, there is no place in the context of Special Relativity to be speculating about time stopping or going backwards.

Again, never said that there would be any two frames of reference that would be flowing backwards from each others' point of view.

 

[evilatom]

It's so cool I stumbled across this thread because that's something I think about a lot. If that were the case and time is moving backwards through us than wouldn't choice be an allusion. It would very much seem like were making decisions that alter what happens next but really were just waiting while what's already been reaches us. Or would our actions ripple forward through the stream and change it before we catch up. Or is there no perceivable future or past at all and the only events that do occur to us are where we intersect the stream in the present like a magnet moving over a row of paper clips just close enough to make them move slightly before it passes on.

 

[Drakkith]

It's so cool I stumbled across this thread because that's something I think about a lot. If that were the case and time is moving backwards through us than wouldn't choice be an allusion. It would very much seem like were making decisions that alter what happens next but really were just waiting while what's already been reaches us. Or would our actions ripple forward through the stream and change it before we catch up. Or is there no perceivable future or past at all and the only events that do occur to us are where we intersect the stream in the present like a magnet moving over a row of paper clips just close enough to make them move slightly before it passes on.

Speculation on time is mostly pointless. The fact of the matter is that time is treated as another mathematical dimension in science to separate events similar to distance. Asking what would happen if time flows backwards is like asking what would happen if forwards were backwards and upside down. It isn't so we can't say how it would be. Time is not flowing and it is not a stream any more than distance is.

 

[arindamsinha]

If we watch a ticking clock we would come to the conclusion that time flows forwards because we see time progressing one tick at a time. One, two, three, four, time must flow forward because things change and progress from one state to another. We know for us time only flows in one direction, it doesn't switch it up and change its mind, what is done is done and it's irreversable. However if time flowed backwards the same would be true, things would change and progress from one state to another, four, three, two, one.

Say for example, if we were standing in the street on a windy day we would find millions of particles of gas whooshing past. In relativistic terms both us and the gas are moving, in one frame of reference we are moving through the stationary gas, however in another frame of reference the moving gas is whooshing past our stationary bodies. Can we apply the same comparisons to the flow of time as we do the flow of the wind? On one hand we observe time to progress forwards, but we our selves don't move backwards in time, we move forwards in time, so if we were to examine time relative to our frame of reference, wouldn't we conclude that time actually flows backwards instead of forwards? We and time couldn't be moving in the same direction because then time would be standing still, everything would be at rest, but we know that isn't the case. We have to flow through time just as time has to flow passed us in order for the universe to exist, otherwise we'd never get from A to B.

Us >>>>> Time
Time <<<<< Us

Interesting question.

My thoughts on this:
We can't treat time as a 'flowing' phenomenon like a river flowing, but we can look at time 'flowing' in a 'forward' (purely conventional) direction based on causality.

Something like a river flows w.r.t. some reference frame. If we are sitting on the banks of the river, it flows in a particular direction w.r.t. the material making up the banks (and us). If we are speeding in a fast boat downriver, we could consider that the river is flowing 'backwards'.

With time, we don't have this luxury of comparison w.r.t 'something else that was not moving'. If we choose a really small slice of time at any point, we may even consider that time 'is standing still' at that moment, as nothing is changing (i.e. no noticeable events are happening).

The 'flow' of time needs to be seen as a succession of 'events', with the order being established only by a rule of causality. An event A which causes another event B to happen establishes that event A happened 'earlier', and therefore time is flowing forward (conventionally) from event A to event B. No amount of logic will allow event B to precede event A (i.e. time to flow backwards).

The only way I think we (as observers) can see 'time flowing backwards' would be like this:

• All the energy and matter of the Universe suddenly reverse course, and start retracing the steps they had taken w.r.t. all other energy and matter in the Universe (like rewinding a movie). For examples, at an atomic level, electrons moving in a particular direction w.r.t. the nucleus in an atom reverse course and start moving backwards, and so on at every level.
• We (the observers) ourselves, somehow fortunately get detached from this Universal energy/matter movement reversal (being somewhere deep in space and strangely not affected by anything else happening in the Universe). The atoms within our bodies carry on towards the future (or forward direction of time).
• Even this would have challenges, as we have withdrawn from the rest of the Universe at least the atoms that got into our body during the last meal, so the rest of the Universe would never be the same again, no matter how diligently it reverses course.

Given this, we need to consider that time does not really 'flow' in the sense of moving w.r.t. anything else in the Universe, except for comparison of the occurrence of certain events before and after other events (i.e. causality).

 

[bahamagreen]

Is it OK for me to be irritated that the OP's original question is not even being grasped yet?

He is not asking about time going backwards like a clock hand going counterclockwise, nor the concept of existential time "flow" being the reverse of our usual causality.

The title should have been "Does time flow backwards or forwards with respect to us in the present?"

He is noting the relativity of ordinary motion and observing that the common sense notion is that we seem to progress forward through time, yet we also use common language to describe the progression of time as also going forward... two things going forward at the same rate - where is the net difference that is supposed to be the "movement" through time?

From a kind of relativistic perspective, if we hold ourselves "at rest", time clearly "moves" with respect to us, into the past... the world seems to become "unchangeable" in the present and gets woven into a hard and fixed history that is laid out "behind us".

To use the loose words; if we are moving forward in time, then time must be still or moving backwards, or moving forward not as fast as us; or if we are still, time must be moving backwards... or any other combination that makes the relative difference in the speed of us and the speed of time result in the relative speed and direction we observe between us and time.

At first this may seems to require a higher level of "background time" against which to compare the movements and directions of time and ourselves, but this is why the OP mentioned relativity - suggesting the solution of avoiding the absolute motion problem using frames of reference.
The OP is posing a similar abstraction to time by seriously apply a concept from relativity - assigning a frame to us and a frame to time, and looking at how a relative "motion" is not consistent with ordinary talk about both we and time "moving forward"...

The fundamental problem may be not so much the attempt at loose abstractions using words like "move" or "progress" or "forward/backward" or even "flow"... it is that our knowledge of the past is totally second hand (memories and physical evidence) in the same degree that our knowledge of the future is totally inferred (derived from premises).

 

[Drakkith]

Why must time itself be doing anything at all? We don't say that distance is moving simply because we pass an object, we say that either we or the object is moving. In the case of time I could say that all of us are moving through time at different rates depending on our relative velocities and other factors.

Of course that suggests that there is an absolute notion of time, something to measure all observers against. Unfortunately there is not, as everyone in an inertial frame will measure their own time as passing normally.

Here's something to consider. We measure time with a clock just like we measure distance with a ruler or some other device. Well, if I am traveling in a direction, and I turn around, am I now going negative distance? No! My change in position is still positive. IE I will move 1 meter per second forward, and when I turn around I will be moving 1 meter per second in the other direction.

So what would "reversing time" do? Would it even change anything? Does the concept even make any sense seeing that time doesn't have 3 degrees of freedom like space does? If there was a direction you could travel in time, and you turned it around, would you not be traveling a positive amount through time still? So even if you did reverse time for yourself perhaps your clock would still tick exactly the same.