# Why does time seem to exist only in a forward direction?

1. Nov 15, 2007

### robmacriner

Rob MacRiner rmacriner@sympatico.ca , robmacriner@hotmail.com

Possible answer to Question: Why does time seem to exist only in a forward direction?

Time seems to only exist in a forward direction because the universe is expanding. If the Universe reaches Critical Velocity and starts to contract ....then time, as we measure time will reverse according to the Big Bang / Big Crunch Theory. The reason for this is that time does not exist without change or movement..... (change or movement of particle matter or energy as we know it). If matter has no movement either expanding or contracting then time does not exit for that matter. However Time can exist around non moving particle matter if something is either expanding or contracting around it.

If the expansion of matter increases as in the case of our universe, or an expanding object, or even light...then time increases relative to the rate of expansion. Example: if carbon A is heated and expands faster than carbon B (which is not heated) then time increases in carbon A relative to carbon B...However as Einstein pointed out...time is relative to the observer...and you need something of contrast to make that comparison....fortunately our universe offers lots of contrast ...otherwise we would have a very difficult time figuring this out. Time being relative to the observer can exist at different speeds based on the rate of expanding matter. If you are on riding on a beam of light than time is much different than your friend riding on a sound wave. Of course time is relative to the observer, therefore your time is much faster only to him, or any body else who is not on a beam of light.

If matter contracts or condenses then time actually reverses…as in the case of a contracting universe…so Planks Quantum would be measured as zero time for the entire Universe…and time starts at the point of the Big Bang (once matter is on the move again)… In the case of a Black Hole, relative to our expanding universe)... there is also no time. (except for matter being sucked into a Black Hole….this matter would be reversing in time, until at which point it becomes part of the Black Hole mass, then time (in a Black Hole) as in Planks Quantum is zero….which is odd because the Universe is still expanding around the Black Hole…but it is consistent with the theory that. Time can exist around “non moving matter” if something is either expanding or contracting

Time as we know it is measured in a forward direction and will continue until the point of critical velocity…at which point time starts to reverse…and for a brief moment…the point where the Universe changes from expanding to contracting…time will again be zero…as in Planks Quantum. However…during the forward direction of time…(while the Universe is expanding)…Black Holes are continuing to suck up matter…and should in theory at some point converge with other Black Holes….Therefore…as the universe is expanding from the Big Bang…there is multitude of matter which is not expanding (Black Holes)…which might well be unexploded Planks Quantum matter from the Big Bang…and the Black Holes with their massive gravitational force are sucking up matter which was attempting to expand but was not able to overcome the stronger force of the Black Hole…like mini-Plank Quantum’s converging within the universe …When the Universe reaches Critical Velocity and then all matter in our Universe starts to contract…heading towards the Big Crunch….the multitude of Black Holes converging (up to that point) should in theory rapidly increase the speed of reverse time …acting as an accelerant force of a contracting Universe with their collective gravitational force …So the reverse of time.(the journey the contracting Universe is taking towards the Big Crunch)...should happen much quicker than the time it took for the Universe to go from the Big Bang to Critical Velocity…That is of course Time relative from the Big Bang to Critical Velocity ……in contrast to …….Time Relative from Critical Velocity to the Big Crunch. Mathematically it might be possible to estimate this time.…

Any Thoughts?

Rob MacRiner rmacriner@sympatico.ca Nov 2007

2. Nov 15, 2007

### mgb_phys

How do you know time is running forward - what are you measuring it against?

3. Nov 15, 2007

### robmacriner

Forward time refers to expansion of matter..it's measured against...it's opposite!

4. Nov 16, 2007

### Chronos

Well, I believe time existed in the past. Does that help?

5. Nov 16, 2007

### robmacriner

That would be the past relative to the observer.

Seems to me that the past as we know it is relative, something might have happened 1 billion years ago to us, and we have a couple of ways of looking at it. i) we can image time as it was, 2) we can see time carried by light which is delayed not unlike a phone call from Austraila to Canada. When does the word Hi actually exist. My time or in the Aussy's time. To me it happened 1 split second after he thinks it did. However when we measure it, it happened at the same time it just took longer to get to me...because it had to travel. Therefore time is relative to change of matter, waves, light etc.???

At least that's the way I understand it.

6. Nov 22, 2007

### robmacriner

Reverse Time

How does one imagine reverse time?

I'm not suggesting that Time will reverse itself as one would rewind a movie. The point is that time as we know it can not exit without particle matter either expanding or contracting. Imagine a container of colored sand 5" high ..packed in a 50 'glass tube on a space shuttle. The color images of sand particles seen from outside the glass, might look like some kind of landscape. Now the sand explodes in the 50’ glass tube ....while the shuttle is docked ..and those sand particles hurl in a forward or expansive direction...up the 50' glass tube...after the explosion. But all of a sudden the space shuttle takes off, and the G forces are very intense, at the same time the particles of sand reach their maximum expulsion. The G forces would bring the sand back down to the base of that glass tube, in a hurry, but when they arrived packed back at the base, now once again 5" high they would not represent the color image of the landscape that was seen before the explosion....The image would be much different. Forward time would be the expansion of the sand after the explosion. Reversed time for the sand would be as the G forces drive the sand back to the based of the glasstube, and pack those colored sand particles back to it's original 5 ". That is the image of reverse time that I see.

7. Dec 5, 2007

### ptalar

I have a hard time understanding why time would go in reverse if the Universe contracts. Time would still be moving forward because the Universe will not contract to earlier configurations. Will your dead great great grandparents come to life. Will WWI and WWII start at the end and work back to the start of the war and so forth. Will the moon become part of the earth again. Will the sun recapture all its solar radiation that has escaped over the billions of years and retain its initial energy level. No, time will still go forward because the matter is not changing to its earlier configuration. Time will go to zero when the Universe is contracted to a configuration similar to moments before the big bang.

Any thoughts, or am I full of babble?

8. Dec 5, 2007

### Pippo

To invert the time direction it is necessary to pass from positive values to a negative one, but this needs to cross the zero border, so a condition with no time at all, but this means no space, no masses, no dimensions, so my answer is that it's impossible in a real situation. However you may get a slower time as much as you will be able to do it (speed).

Last edited: Dec 5, 2007
9. Dec 6, 2007

### fasterthanjoao

Not related to the subject, but I would note that it's unwise to post your email address anywhere public on the internet where some unfriendly spambots are nodoubt lurking.

10. Dec 6, 2007

### Hurkyl

Staff Emeritus
The change in time per unit time is +1. It couldn't be anything else. :tongue:

(I intend both usages of the word "time" to refer to the same thing)

11. Dec 19, 2007

### ThienAn

To me, i believe the question was asked without any appropriate considerartion. No matter if the universe is expanding or contracting, it still is a theory. It is a very elegant question to ask, but it is ultimately wrong to ask. The question should had been: "In where the time is moving forward?" Because outter space, and inner space work as a knitted fabric. They relate, intercept, and compelling each other therefore we are living in an environment of both inner and outter circle. And I agree with Pipo that we would not find out the answer to this question very soon, at least in this lifetime, this generation, but still that was a great question.

12. Dec 26, 2007

### robmacriner

Reverse Time

I'm not suggesting that Time will reverse itself as one would rewind a movie. The point is that time as we know it can not exit without particle matter either expanding or contracting. Imagine a container of colored sand 5" high ..packed in a 50 'glass tube on a space shuttle. The color images of sand particles seen from outside the glass, might look like some kind of landscape. Now the sand explodes in the 50’ glass tube ....while the shuttle is docked ..and those sand particles hurl in a forward or expansive direction...up the 50' glass tube...after the explosion. But all of a sudden the space shuttle takes off, and the G forces are very intense, at the same time the particles of sand reach their maximum expulsion. The G forces would bring the sand back down to the base of that glass tube, in a hurry, but when they arrived packed back at the base, now once again 5" high they would not represent the color image of the landscape that was seen before the explosion....The image would be much different. Forward time would be the expansion of the sand after the explosion. Reversed time for the sand would be as the G forces drive the sand back to the based of the glass tube, and pack those colored sand particles back to it's original 5 ". That is the image of reverse time that I see....although these answers to this question lurk somewhere between Philosophy and Science....

I'm not sure at which point science crosses philosophy, obviously there is a point. Clearly anything outside our universe is philosophy. I think however that even scientist can get focused on ideas that they believe are true and then set about to validate that belief. There really is no other way to approach it, they have to start somewhere…..and all is good provided pure science and objectivity stay intact. Philosophy can, and should play a big role in this pursuit.

Metaphysics, existentialism and cosmology are in many ways very much on the same page….but only science can give us clear answers…and as you know that often takes a very long time…Hopefully scientist can be patient, open minded and diligent…and slowly we move towards a truth….or at least a glimpse at the truth…It’s hard to believe the real truth could every be realised…..but we can not assume defeat, we have to keep moving forward regardless how complicated and some times fruitless it seems….and you just never know…..what we will find along the way.

13. Dec 27, 2007

### Eduffy80911

Time is the ocurrance of interaction or "observation" or data exchange. In other words, something has to happen to something for time to take place. Time only goes "forward" because events, interactions, observations, exchanges, can't un-occur.

Of course if they did, you'd never know it. I suppose one could revert to a "saved" version of the universe, but it would be absent any recollection of anything that happened after that point.

14. Dec 27, 2007

### robmacriner

Time Reverts to the Saved version of the universe

That is pretty much the way that I see it. However the arguement of zero time can take on many different forms.....in my mind zero time might not ever truely exist, because matter is either expanding or contracting...and for "that moment" of the change between the two....I'm still perplexed... However since time is relative to the observer, and because we can not observe or measure anything other than what we see...we might be locked in that perception for quite some time...

15. Dec 27, 2007

### sysreset

I am just speculating here, but it occurs to me that whenever matter is converted into energy one could say time stops from the perspective of the matter. Time stopping in this sense is synonymous with the matter ceasing to exist. And from the 'perspective' of the energy, time may distorted. I am doubting if one can posit a time reversal during these conversions, though.

16. Dec 27, 2007

### robmacriner

Time stops?

I'm also just speculating, but I see it a bit differently. Time can only exist if matter is turning into energy.....or expanding. (unless in the case of a Black Hole where time is contracting).. Example...the head of a match has no time relative to the observer. If the match stays unlit for 50 years...some decomposition of the sulphur would occur and time would be relative to the observer in respect to whatever change has taken place with the sulphur and the paper stick attached to the sulphur. However if the match is lit...and gives off energy... as in fire (rapid oxidation) ....then the time for that sulphur and paper expanding and changing state is much more rapid....(to the observer)......This also is a good example of entropy...the second law of thermo dynamics.....the questions ofcourse now become more complex…...as in what happens to renewable energy and non renewable energy relative to time. But if the universe is expanding then so are the gases emitted from that match.....over and above what we see...while witnessing the match burn for 30 seconds.

I've often been amazed sitting on the dock at my cottage...overlooking the lake on a calm day. Witnessing not one wave or even ripple in the water...which blows my mind….because I know the universe is expanding at a very rapid rate, and I know that we are rotating approximately 1000mph on the axis of the earth...all at the same time as we are rotating around the sun at whatever speed that is. ….I find it very difficult to believe, based on that knowledge that the lake could be so still…. But I gain comfort and confidence in our environment and in my existence by also knowing that as in time.....everything is relative to the observer. Which also very much includes enjoying a unsplit cup of tea on an aircraft travelling at 740mph 35,000ft above the earth’s surface.

17. Dec 28, 2007

### Sorry!

all i have to say is s=k logW you kno what i'm sayin/. i kno u kno what i'm sayin.

anyways look up thermodynamics... more specifically the second law of thermodynamics and the arrow of time ... if you wanted more indepth you could involve quantum physics in your little expedition of finding the flow of time and the 'forward' direction it has what is going to happen with time etc. etc.

interesting topic though i must say i spent the LONGEST time trying to answer alot of these questions haha :D