Time

[Rumfrd]

TIME

Why is the future not knowable in the way the past is knowable? Why does time seem to flow in one direction? Why is there an arrow of time? What is time? These seem like difficult questions, but they are not. There is a simple path to an accurate understanding of their answers.

To begin to understand these questions, consider the expansion of an inflating balloon. Its surface is expanding such that if you pick any point on the balloon, every other point on the balloon recedes from the point you picked. If you think about how this works everywhere on the balloon, you realize that what is really happening is that new area is flowing in the balloon's surface as it expands. At every single point on the balloon's two dimensional surface, new length and new width are appearing, and spreading in all directions.

Area is two dimensional and space-time is four dimensional, but the same kind of thing is happening in our Universe, and by Universe, I mean the visible portion of the universe we inhabit, which may be infinite. The Universe we can see, (which I will designate with a capital U) is expanding. It has been expanding for 14.8 billion years. The mass the Universe contains is composed of matter and energy. They are inter-convertible (e=mc squared) and both have mass. The mass the Universe contains is not increasing. Since the Big Bang, the mass has been constant. It is a lot cooler now than the incredibly hot quark-gluon mix it started as. It cooled to become mostly hydrogen and then fused to heavier elements in stars and captured neutrons etc. to become the large array of elements we see today, but it's all still the original mass we started with, just a lot cooler, and a lot more complex. It has been expanding for 14.8 billion years. It expands this second, at a rate which is still homogenous everywhere in the Universe.

The space-time that contains this mass is growing ever larger, but no new mass is appearing. Only new space-time is appearing. Space-time is not at all material, no more than up and down, or left and right are material. It is a set of 4 continuous dimensions, 4 directional axes if you will, left/right, up/down, forward/backward, future/past; all continuous and at right angles to each other. Continuous interchangeable dimensions at right angles to each other are called a continuum because they are the same. The only difference is the way we are pointed. If we turn 90 degrees, the front/rear dimension becomes the left/right dimension. The three dimensions of space are only arbitrarily designated. In actuality, all four dimensions are the same, but we do not perceive time as a space dimension. Einstein has proved it to be a dimension of the same continuum, and many experiments have confirmed this. But our perceptions see time as a flow.

Because all of its parts grow at the same rate, second by second, the Universe is flat. The space-time expansion rate has changed, in fact, it was explosively larger in the beginning, but what ever that rate happens to be at any particular second, it is identical across the Universe, and the Universe stays flat. It expands uniformly.

Consider, that, most importantly, not just space is flowing in the expansion. Time is flowing also. New space and time flow in our Universe just like new width and length flow in the balloon's surface. We understand the creation of new space in an expanding Universe. The Universe is getting bigger, adding space, growing outward from every point. But the creation of new time, we experience personally. New time flows everywhere as it appears in the expansion of space-time, but living things perceive this flow directly, as the passage of time. Only our instruments can detect the flow of space. The difficulty of understanding Cosmology is not the science, but how we perceive time.

In the expansion, in the passage of additional time, change becomes possible. If time did not increase in the Universe, nothing in the Universe could change. Time's expansion ages the Universe, equally, everywhere. The expansion of time which has not yet taken place is the future. Think about it. The flow of space must also be the flow of time, because if time did not flow, there could be no change. Without the flow of time, the Universe could not have expanded or changed in any way. It could not even have originated. Without the flow of time, there is no flow of space. They are and must be, a continuum.

This demonstrates the true unity of space and time, which, no matter how differently we perceive them, are like length and width, a set of dimensions in a continuum. But the space-time continuum encloses our entire Universe. It is the continuum whose growth, whose endless supply, directed by the laws of our Universe, has developed the matter of our Universe from the beginning. The continuous supply of space-time has allowed change and development of that matter. It has allowed it to produce life, evolution, and even thought. The flow of space-time is not a remote, esoteric abstraction. In summary:

The Universe has been shaped by its laws from the beginning. They act like its DNA. They developed the original mass from a uniform hot mixture to an extensive and diverse array of elements. They developed that diverse array of elements to a diverse array of life, and then developed that diverse array of life to a diverse array of intelligence. Eons of complex, multistage development, were made possible through one process, the expansion of the space-time continuum.

[MigL]

Interesting proposal.

That we perceive the expansion as space-time as the flow of time into the future.

 

But I gotta ask...

If the universe would, at some point, slow down and start collapsing ( cyclic universe ), would we perceive time as going backwards ?

[Mordred]

It's close to what GR describes, but remove time reversal. A region compressing to a higher mass density time will slow down to an outside observer.

 

However even though the Universe was denser in the past. At any spacetime slice of the Universe. There is no mass gradient so no time dilation.

I'm not sure if the OP though is suggesting time reversal.

The reason for the Universe being described above as flat is however wrong.

 

" Because all of its parts grow at the same rate, second by second, the Universe is flat. The space-time expansion rate has changed, in fact, it was explosively larger in the beginning, but what ever that rate happens to be at any particular second, it is identical across the Universe, and the Universe stays flat. It expands uniformly."

There is numerous flaws in the above,

However those flaws could be descriptive flaws.

 

At least you got the homogeneous and isotropic aspects correct.

This demonstrates the true unity of space and time, which, no matter how differently we perceive them, are like length and width, a set of dimensions in a continuum. But the space-time continuum encloses our entire Universe. It is the continuum whose growth, whose endless supply, directed by the laws of our Universe, has developed the matter of our Universe from the beginning. The continuous supply of space-time has allowed change and development of that matter. It has allowed it to produce life, evolution, and even thought. The flow of space-time is not a remote, esoteric abstraction. In summary:

 

The Universe has been shaped by its laws from the beginning. They act like its DNA. They developed the original mass from a uniform hot mixture to an extensive and diverse array of elements. They developed that diverse array of elements to a diverse array of life, and then developed that diverse array of life to a diverse array of intelligence. Eons of complex, multistage development, were made possible through one process, the expansion of the space-time continuum.

Time has a forward direction though At a different rate depending on observer for a region of spacetime that is compressing or shrinking.

 

According to GR. So the above isn't accurate. I have no idea why you need the living vs machine perception aspects.

 

The last quoted section isn't particularly related at least not how I read that section. Please clarify

 

!

Moderator Note

hopefully you will be one of the extremely rare posters that presents a speculative model that will provide some mathematical rigor. As per the speculation rules

http://www.scienceforums.net/topic/86720-guidelines-for-participating-in-speculations-discussions/#entry839842

 

Edited April 15, 2016 by Mordred

[michel123456]

That is essentially one of my first questions when I joined this Forum.

The question is, following the accepted model of physics:

Is Spacetime expanding, or is Space only expanding?

The answers I got from experts here pointed to the "Space only" expanding.

Which means that if you want to introduce the concept of "expanding Spacetime" I am afraid you have to make a change in standard physics somewhere.

 

TIME

 

(...)

 

Because all of its parts grow at the same rate, second by second, the Universe is flat.

Second/second has no unit, it is a kind of tautology, it is not a rate.

The space-time expansion rate has changed, in fact, it was explosively larger in the beginning, but what ever that rate happens to be at any particular second, it is identical across the Universe, and the Universe stays flat. It expands uniformly.

 

Consider, that, most importantly, not just space is flowing in the expansion. Time is flowing also. New space and time flow in our Universe just like new width and length flow in the balloon's surface. We understand the creation of new space in an expanding Universe. The Universe is getting bigger, adding space, growing outward from every point. But the creation of new time, we experience personally. New time flows everywhere as it appears in the expansion of space-time, but living things perceive this flow directly, as the passage of time. Only our instruments can detect the flow of space. The difficulty of understanding Cosmology is not the science, but how we perceive time.

 

In the expansion, in the passage of additional time, change becomes possible. If time did not increase in the Universe, nothing in the Universe could change. Time's expansion ages the Universe, equally, everywhere. The expansion of time which has not yet taken place is the future. Think about it. The flow of space must also be the flow of time, because if time did not flow, there could be no change. Without the flow of time, the Universe could not have expanded or changed in any way. It could not even have originated. Without the flow of time, there is no flow of space. They are and must be, a continuum.

As I stated above, that is not what I understand from known physics. And also, doesn't that impose the existence of a Universal Now? Edited April 16, 2016 by michel123456

[Rumfrd]

The point I am trying to make is that for each particular observer, time moves from future to past, regardless of the local curvature of space, or the existence of other observers who's space time coordinate system are tilted with respect to that particular observer (no universal now). The increase of time in the Universe coexists with the increase of space in the Universe. Both are experienced by every observer, though they are experienced in different subjective forms. The existence of time prior to the Big bang is consistent with this point, but also consistent with this point is the origin of space-time in the Big Bang. There may be consensus in scientific opinion, but if there is proof for the existence or nonexistence of time prior to the BB, I am unaware of it. Please direct me to it.

 

Also, I wrote second by second, not seconds per second, though seconds per second is a legitimate unit. The unit of Elastic stretching under stress is inches per inch. This is not a tautology, but a legitimate engineering unit.

 

I'm sorry, I don't understand the "living vs machine perception aspects" reference. Please explain.

[Rumfrd]

That is essentially one of my first questions when I joined this Forum.

The question is, following the accepted model of physics:

Is Spacetime expanding, or is Space only expanding?

The answers I got from experts here pointed to the "Space only" expanding.

Which means that if you want to introduce the concept of "expanding Spacetime" I am afraid you have to make a change in standard physics somewhere.

 

Second/second has no unit, it is a kind of tautology, it is not a rate.

As I stated above, that is not what I understand from known physics. And also, doesn't that impose the existence of a Universal Now?

We are three dimensional creatures living in four dimensional spacetime. We can not perceive the 4th dimension except as a three dimensional cross section. What we call time could well be a "space" dimension whose expansion flows in a direction we can not perceive.

[michel123456]

We are three dimensional creatures living in four dimensional spacetime. We can not perceive the 4th dimension except as a three dimensional cross section. What we call time could well be a "space" dimension whose expansion flows in a direction we can not perceive.

Yes I agree that we are 3dimensional.

However some other members here believe that we are 4dimensional beings.

 

My view of things is that we are 3dimensional beings "moving" through a continuum called spacetime. To me, the continuum is a kind of receptacle: it does nothing. But I have not found any agreement on this either. Other people like you will say that time is the thing that flows.

Edited April 25, 2016 by michel123456

[Rumfrd]

Well, the explanation I propose suggests why the past is knowable but the future is not. The future is expansion that has not taken place yet. We experience only the frontier of time, not the past except through the present, though we are physically continuous with ourselves in the past; at least that is what I believe since I remember no temporal gaps in my physical existence. We experience only the frame we live in, as it moves in the continuum. I see what you are suggesting about movement through the continuum, but I don't see the future as fixed.

 

Alfred North Whitehead in his book "Process and Reality" proposed that the universe was continually coming into existence. In other words, that the past and present are real, but the future not yet real. Any of these explanations allows, as I think your explanation must, that living things are able to change the continuum. Perhaps the only differences are semantic. We have very little in the way of physical referents for the concepts with which we address these issues.

Perhaps the only scientific paper I know of, that directly addresses the nature of consciousness was written by Roger Penrose and an Anesthesiologist named Hameroff. They proposed that the tubule structures in neurons contain many quantum wells whose contents were wave function linked as well as physically linked. The physical linkage provided distributed processing that was the precursor to perception. They proposed that this distributed processing (like the game of LIFE), was preconscious until the quantum linked processing of many states, self collapsed (Penrose) to a real perception. The collapse was the instance of perception. Their evidence was the coincidence of the calculated timing of the quantum processes with known brain wave frequencies, plus other things. I read this paper years ago, so forgive any inaccuracies in my summary. No significant work that I know of has been done to test this paper's validity. This is an area where Scientists fear to tread, but it is interesting. I remember asking in Biology how a single celled animal could do as much as it did without a nervous system. If you want to read it, the title is:

 

Orchestrated reduction of quantum coherence in brain microtubules: A model for consciousness

[michel123456]

Well, the explanation I propose suggests why the past is knowable but the future is not. The future is expansion that has not taken place yet. We experience only the frontier of time, not the past except through the present, though we are physically continuous with ourselves in the past; at least that is what I believe since I remember no temporal gaps in my physical existence. We experience only the frame we live in, as it moves in the continuum. I see what you are suggesting about movement through the continuum, but I don't see the future as fixed.

 

Alfred North Whitehead in his book "Process and Reality" proposed that the universe was continually coming into existence. In other words, that the past and present are real, but the future not yet real. Any of these explanations allows, as I think your explanation must, that living things are able to change the continuum. Perhaps the only differences are semantic. We have very little in the way of physical referents for the concepts with which we address these issues.

Perhaps the only scientific paper I know of, that directly addresses the nature of consciousness was written by Roger Penrose and an Anesthesiologist named Hameroff. They proposed that the tubule structures in neurons contain many quantum wells whose contents were wave function linked as well as physically linked. The physical linkage provided distributed processing that was the precursor to perception. They proposed that this distributed processing (like the game of LIFE), was preconscious until the quantum linked processing of many states, self collapsed (Penrose) to a real perception. The collapse was the instance of perception. Their evidence was the coincidence of the calculated timing of the quantum processes with known brain wave frequencies, plus other things. I read this paper years ago, so forgive any inaccuracies in my summary. No significant work that I know of has been done to test this paper's validity. This is an area where Scientists fear to tread, but it is interesting. I remember asking in Biology how a single celled animal could do as much as it did without a nervous system. If you want to read it, the title is:

 

Orchestrated reduction of quantum coherence in brain microtubules: A model for consciousness

My view is different. I think that this research of the ever vanishing present time is wrong.

To me, not the continuum nor the universe is sliding from the past to the future.

My opinion (it is only an opinion) is that all "things" in the universe change coordinates. Spatial coordinates and time coordinates.

When you stand still, your spatial coordinates don't change (as observed by yourself) but your time coordinates change.

And to me, the "changing coordinate in time" is nothing different from the "changing coordinate in space". That is to say: there is nothing metaphysical in the passage of time, not any more metaphysical than for a change in coordinate in space.

--------------------------

 

Note: there is an important consequence of my "opinion". Because we change coordinate in time it means that we don't continue to "exist" somewhere in the past. That is because we cannot be alltogether in the present and in the past. As you stated before, we are 3dimensional beings, we are not extruded in the past.

Edited April 26, 2016 by michel123456

[Rumfrd]

Note: there is an important consequence of my "opinion". Because we change coordinate in time it means that we don't continue to "exist" somewhere in the past. That is because we cannot be alltogether in the present and in the past. As you stated before, we are 3dimensional beings, we are not extruded in the past.

 

My view is different. I think that this research of the ever vanishing present time is wrong.

To me, not the continuum nor the universe is sliding from the past to the future.

My opinion (it is only an opinion) is that all "things" in the universe change coordinates. Spatial coordinates and time coordinates.

When you stand still, your spatial coordinates don't change (as observed by yourself) but your time coordinates change.

And to me, the "changing coordinate in time" is nothing different from the "changing coordinate in space". That is to say: there is nothing metaphysical in the passage of time, not any more metaphysical than for a change in coordinate in space.

--------------------------

 

Note: there is an important consequence of my "opinion". Because we change coordinate in time it means that we don't continue to "exist" somewhere in the past. That is because we cannot be alltogether in the present and in the past. As you stated before, we are 3dimensional beings, we are not extruded in the past.

Michel, You are saying that accumulated space persists, but not accumulated time? The mass we are composed of has existed in one form or other since the BB. How then could it not extend into the past? If matter that existed in the past still exists, well, is it not "extruded in the past"? And yes, my thesis is that time flow is not metaphysical, anymore than the flow of space due to the expansion. We know time's expansion flow as a changing 3D cross section, because 4D flow is not perceivable to beings who perceive only 3 dimensions.

 

Matter has not expanded with spacetime, because it is bound by atomic, chemical, and gravitational forces. Spacetime just expands, flowing without friction, even in the very interior of a neutron star. Every form of mass in the continuum is 4 dimensional. When I say we are three dimensional beings, I am referring to the way we experience the Universe with our senses, we are conscious of a changing 3D cross section of the time dimension. That is what I am saying.

 

You are saying we are discrete beings travelling through the continuum. Alfred North Whitehead said (in many words) that the Universe is continually coming into being. Our sensory experience will never distinguish between these, only our minds.

[StringJunky]

 

We know time's expansion flow as a changing 3D cross section, because 4D flow is not perceivable to beings who perceive only 3 dimensions

The 4th dimension is not a spatial dimension, it is a temporal one i.e. time.

[Rumfrd]

When an observer A from his frame sees observer B acquire velocity, B's frame tilts, rotating spaceward as seen by A. B's time axis moves into what A sees as space. It is a continuum, space and time are interchangeable dimensions.

 

At the event horizon of a black hole, an external observer is seeing time rotated 90 degrees as space. Space and time are interchangeable dimensions.

 

But we perceive in three dimensions. What we perceive is a changing 3 dimensional cross section of a 4 dimensional continuum. It changes because time is expanding in the Universe (I believe) as well as space. The Universe accumulates both because (I believe) it is expanding in 4 directions, not three. Whether time pre-existed is moot. Either way, the Universe is accumulating seconds as it ages, and the process of accumulation appears to our senses as I have described. To wit: a changing 3D cross section of the 4 dimensional continuum, which changes because time is expanding and the seconds flow, or if you believe time preexisted and the expansion is 3D only, time is accumulating because seconds have always flowed.

Edited April 27, 2016 by Rumfrd

[Mordred]

the last post makes no sense. Time isn't a force that can cause expansion. So it doesn't make any sense to state time is expanding the universe. Time will continue even if the universe is contracting.

 

Time isn't a spatial dimension it is merely mathematically treated as a vector coordinate. Mathematically you can portray this as your tilt but this doesn't reflect reality.

[Rumfrd]

Space is not a force either, but our universe is accumulating it. And can you show me a contracting Universe?

 

The tilt is just a (valid) graphical representation of frames moving with respect to each other. Such a graphical representation also shows what you call "time compression" due to relative motion, and Lorentz contraction as relative projections between frames.

 

Some people think mathematically, others are good at rotating spaces. I did not invent these diagrams. They are scattered throughout the literature along with the math.

Edited April 27, 2016 by Rumfrd

[Mordred]

space isnt a force its merely a volume not a substance. Time also isn't a force or substance. It is simply a measured rate of change or duration ( a property). To say accumulate space is slightly inaccurate as it implies a substance like property

Edited April 26, 2016 by Mordred

[Rumfrd]

OK, but is not volume a substance property? Can you expand space without accumulating volume? I agree the words are semantically distinct.

[Strange]

OK, but is not volume a substance property?

 

Not really. What is 1 litre made of? What is a square metre made of? Or a mile? Or a second?

 

They are just measurements of the distance between things.

[Rumfrd]

Ah, I see what you mean. A physical property like mass or charge. Volume is a metric, space is not a metric, I agree with you, but space can be measured by a metric. And that metric can increase, and that means that the property measured by the metric can increase, no? Anyway that is what I meant by "space is accumulating". Forgive my short cut, but total semantic rigor causes people to lose track of the essential ideas very quickly.

 

I suppose I could have written "the volume of space is accumulating". Space is after all, a set of directions. But I don't see how the volume of the Universe could increase unless space were expanding.

 

Anyway, you described space as a volume above.

 

space isnt a force its merely a volume not a substance. Time also isn't a force or substance. It is simply a measured rate of change or duration ( a property). To say accumulate space is slightly inaccurate as it implies a substance like property

 

Time is not a property or a metric, it is a dimension. The second is the metric of time yes, specifying rate or duration. If my writing must be rigorous, yours should be too, no? But I take your meaning of the above quite clearly. And yes, I agree.

Edited April 27, 2016 by Rumfrd

[michel123456]

When an observer A from his frame sees observer B acquire velocity, B's frame tilts, rotating spaceward as seen by A. B's time axis moves into what A sees as space. It is a continuum, space and time are interchangeable dimensions.

(...)

Yes I agree.

That is the reason why I believe that a change of coordinate in time is very similar to a change of coordinate in space.

 

Another reason is mass. I don't believe that mass increase as time passes by. IOW I don't believe that when a second ticks the mass of the Universe multiplies. I believe that the mass of the Universe remains unchanged as time passes by (not regarding eventual Theories of cosmological mass creation). Time has not the property of multiplying the mass of an object which means that (to me) the mass of an object translates from one instant to another. When an object is at a time stamp T2, it cannot remain "somehow frozen" at time stamp T1. The object has "moved" from T1 to T2. It has not "extended" from one time stamp to the other.

 

I hope the above is clear.

Edited April 27, 2016 by michel123456

[Rumfrd]

I never meant to imply that the mass/energy of the Universe was altered by the expansion, either 3D or 4D (if 4D expansion exists). I was taught mass/energy is a constant, including dark mass/energy. So, I agree time does not alter mass, mass is conserved. What has changed is the position in spacetime being observed between time stamp T1 and time stamp T2. If the object is a rock, is it not a rock at any time stamp observed between T1 and T2? And by observed, I mean its mass is observed as well. I certainly don't mean that every possible mass observed is conserved. That mass would be infinite, no? But I apologize for confusing language referring to the physical continuity of mass's extension into the past. I never meant that the mass of an object per se is continually increasing. Nor that a physical link to the past persists. I should have said the identity of the rock extends into the past, or its world line. I apologise for confusing and inexact language.

 

But let me define my view of the passage of time between T1 and T2.

 

Case 1: Call it Exterior Time, let Case 1 be the prevailing consensus view of time as I understand it, i.e. time pre-existing the Universe (a tautology IMHO), allowing the expansion to reverse etc.

 

Case 2: Call it Interior Time (what I believe), meaning time is an artifact of expansion, and limited to the Universe.

 

The object in both cases has moved in time, either Interior Time or Exterior Time. There would be no difference. There would be no difference with respect to mass, there would be no difference with respect to position. No difference with respect to any time stamp between T1 and T2. The cases are identical, objectively and subjectively for the observer. In both cases, time is the 4th Dimension. The only difference is the pre-existence of the time dimension.

 

But, perhaps I am wrong, and the pre-existence of time is not a tautology. I think ideas outside the mainstream should be examined if they are logically consistent, even if it means temporarily accepting disagreeable postulates.

Edited April 28, 2016 by Rumfrd

[DanTrentfield]

If I'm not wrong time is the simple non-co-occurrence of two events, it's literally just a differential between point A and point B because they don't exist in the same instant, or one is slightly younger than the other. I think we all need to go back to that simple thought, because much like a plane in geometry in order to have a plane you have to have a differential between two points. I personally think time just happens to be that differential.

[StringJunky]

If I'm not wrong time is the simple non-co-occurrence of two events, it's literally just a differential between point A and point B because they don't exist in the same instant, or one is slightly younger than the other. I think we all need to go back to that simple thought, because much like a plane in geometry in order to have a plane you have to have a differential between two points. I personally think time just happens to be that differential.

Time is relative, so you are not wrong.

[michel123456]

If I'm not wrong time is the simple non-co-occurrence of two events, it's literally just a differential between point A and point B because they don't exist in the same instant, or one is slightly younger than the other. I think we all need to go back to that simple thought, because much like a plane in geometry in order to have a plane you have to have a differential between two points. I personally think time just happens to be that differential.

I cannot number how many tautologies they are in this statement.