TIME IS THE EXPANSION OF SPACE (and other thoughts)

[Boilermaker]

When I was a child in primary school, in about 1960, I was being taught a prayer by my teacher in Catholic School. The prayer spoke about God being Eternal and I asked later, when God was Born. That question was answered with "God is from Before Time Began" which blew my little mind..........TIME BEGAN????

so, since then I have had this question, what is time?

I have asked it many times over the years, I was sent to Senior Secondary School at age eleven and I started an Arts and Science course which provided a Physics teacher. I asked that teacher in 1966 what is Time? I was given the answer, "time is movement, as long as an atom vibrates there will be time" but that was not satisfactory to my mind. It didn't give me the impression "ah, now I see" I was still left with that itch I couldn't scratch, he scratched, but he missed the spot that was itching me.

one day the answer came to me.

I believe that Time IS the Expansion of Space and what we know about Time is explained by the Expansion. I believe that Gravity affects the expansion and so it affects time. I believe that since Gravity affects it so does velocity for the same reason and if you use your own mind you might be able to answer some other questions by thinking of time as the Expansion of Space and nothing else.

 

[derekmcd]

Not really clear what your definition of time is and how it relates to expansion, but it sounds like you are relating it to entropy and the first law of thermodynamics.

You physics teacher and their reference to "movement" may have been offering the simple explanation of time as being a measurement of the rate of change.

 

[Boilermaker]

Hi,first of all, thank you for the engagement.

what I mean by time is what is commonly referred to as the fourth dimension. I can understand it's use as a dimension, we can arrange to meet at a future point in space, say at the corner of two streets and we can arrange to meet there at a set point in time. We use time as one of our coordinates, so I do understand that.

But we speak of time as if it could somehow be separated from the three visible space dimensions, like width or depth is. We dream of time travel and hope that with some future machine we could travel through time to the past or future. I have to admit, I love fantasy and those stories entertain me a lot. But the way I've come to imagine time, at least at this moment in it, we could never go back in time to our own past. Because, if the Universe really is expanding then time is not like any imaginary river at all, if it is, it's like a river in which not only the water travels forward but so does the bed of the river and the banks and the fields and everything surrounding the river. I think that if we could surpass the speed of light and suppose for a second that did have the effect of time reversal, we would not be able to find the past we just experienced because it has traveled with us to what is now the future of that past and what we might find would be another different past moment.

that may be hard to follow but I hope you get my gist.

there have been many movies made about time travel and there are even people talking about it now, if you look at this link: http://www.youtube.com/watch?v=X02WMNoHSm8 you will see what I'm talking about.

as he says, you could "come back before you left" but what I'm saying is that if you went back two years in time you would not find yourself two years ago, because not only did you move through time but everything and everyone did, but only you went back.

but, if time is brought about by the expansion of space then we really can't go back at all, the expansion is a change, time brings change, if the expansion of space stretches the bonds of the Nuclear forces holding our atoms together then we would see the deterioration of everything in space.........over time.....as they fall apart like an old barn or car on a set of time lapse photographs.

of course, I might just be nuts.

 

[SpeedFreek]

Aside from any notions of time travel, if time is the expansion of space, the implication seems to be that if the universe wasn't expanding, there would be no time passing.

Time passes at 9,192,631,770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the cesium 133 atom per second.

If the universe weren't expanding, would atoms stop "vibrating"? Would all physical processes stop happening?

If there were no dark energy and the critical mass of the universe were enough to bring the expansion to a halt and then start the universe collapsing back on itself, would time move backwards?

Come on now!

 

[Boilermaker]

hahaha! that's hilarious!!

If the universe weren't expanding, would atoms stop "vibrating"? Would all physical processes stop happening?

If there were no dark energy and the critical mass of the universe were enough to bring the expansion to a halt and then start the universe collapsing back on itself, would time move backwards?

no, I do not believe atoms would stop vibrating or any physical processes stop.

if there even is dark energy........if Gravity overtook the expansion force and the Universe began to contract I don't think you would notice much at all, because the Universe was smaller yesterday than it is today and smaller still a million yesterdays ago and it didn't run in reverse then did it? No, but now this is another matter and maybe we can try to imagine this together? I never tried to imagine what would happen if the expansion stopped and reversed...........but before you poo-poo the notion of time reversal, which I never mentioned and had no intention of ever mentioning, I have read of that in articles about the Big Crunch.............but don't ridicule it as if I said it, I never did.

no,

I am talking about time itself, not atomic clocks. I'm talking about the cake and your talking about the more accurate ways to slice it.

what I am looking for is the explanation of the difference between two devices measuring time passage by vibrations as you described when one is placed in a plane and the other on the ground. I am sure you must know of the experiments.

I am not talking about calendars or clocks, but time itself. It is frequently called space/time and it cannot be separated from space and is relative to the observer.................you know all this.

tell me why can't we separate time from space? tell me why time slows down at the event horizon? tell me why it slows down with increasing velocities?

 

[SpeedFreek]

I am talking about time itself, not atomic clocks. I'm talking about the cake and your talking about the more accurate ways to slice it.

That's a very nice way of putting it, I like that one!

what I am looking for is the explanation of the difference between two devices measuring time passage by vibrations as you described when one is placed in a plane and the other on the ground. I am sure you must know of the experiments.

I am not talking about calendars or clocks, but time itself. It is frequently called space/time and it cannot be separated from space and is relative to the observer.................you know all this.

tell me why can't we separate time from space? tell me why time slows down at the event horizon? tell me why it slows down with increasing velocities?

Unfortunately we can only predict what happens using models based on equations. These models can be descriptive, but they are not reality, they are a mathematical or geometrical description of what reality does. So we cannot give you the "why", we can only give you the "how" and we need clocks and rulers to describe that, but that is not what you want here, is it?

All I can say is that both time and space seem to be curved in the presence of gravity or acceleration and they curve in a way that seems to be linked. When you look into it further you find that you cannot actually separate the two. But you seem to know that already.

 

[Boilermaker]

well, to put it simply, do you think that it's possible that the reason you can't separate time from space is because time is simply the expansion of space?

I just went to see what Hubble's constant was, because if time is the expansion then Hubble's constant is the rate of the expansion. I just read about the Hubble parameter for the first time, and there is also something called Hubble time.

I did not know that. Hubble time is simply the rate of expansion today run in reverse gets you an age for the Universe, but that would only be accurate if the expansion is actually constant and I don't believe it is. I say I don't believe it because there is an Inflationary theory that says it wasn't constant back near the beginning, if there really was a beginning and it's increasing now, so there's no reason really to even think of a constant, it should be thought of as more of an average, Hubble's average......anyway, if you attained a velocity through space equal to the rate of expansion then for you time should stop....I think. I think if you reached that velocity then you could go all over the Universe and no time would pass for you at all. The Universe would age through time passage but for you no time would pass at all, I think.

but, maybe the Universe isn't expanding at all, maybe Dark Matter around the Galaxy somehow drags light waves and they all lose energy and become red shifted? Maybe the Dark Matter absorbs energy but does not emit it and so it robs light of energy and lengthens its wave length.....could that happen?

why does energy travel as a wave at all? I thought about that and my mind is saying "because it has to" my mind then asks "why does it have to?" and then it answers "because space dictates it" so that leads me to imagine space as a field of tiny spheres or strings curled up and transmitting energy like little cogs,..........mental picture of this?

imagine you have a box on the floor and it's full of little ping pong balls and somehow you could impart energy into one in the center of them all making it spin, if you could do that and watch it, after a few seconds the center ball would turn the rest like little cogs and the box full of ping pong balls would undulate and look like it had come alive, it would develop a wave pattern.

now imagine you could somehow impart a forward force as well as a spin to the balls, imagine that. It would look like a 3D wave traveling through the box. Now imagine the whole room is full of those little balls and you were able to continue imputing energy and spin into one ball after another and sending it through the room completely filled with the balls. Eventually every ball in the room would have turned as the energy from the single balls you input the initial charges of spin and forward force traveled across the room. Can you imagine that?

well, imagine that the ball you put spin into is the electron and the rest of the balls are space, in fact without your spin/charge the room is filled with balls without energy and undetectable. The nearest balls to the electron spin with residual charge and give the electron a sort of fuzzy indeterminate boundary, it's uncertain where the electron ends and space begins.....because since space is turning with the charge it appears fuzzy without a border or solid edge and it doesn't have one.

now, imagine that you put the double slit experiment set up in this room, your initial electron goes through and makes one stripe, but eventually the residual effect of the spin on space, the little spheres, makes it appear eventually as if more than one electron were present as two slits create an interference pattern, this is due to space spinning along side the electron charge/spin.

imagine you put a target in front of your electron, it would receive the impact of your actual spin/charged electron with the forward direction as if a particle hit it, compared to the residual almost undetectable spin on the rest of the balls, spheres, strings, it would appear like a lone particle striking the target, but when you look to see what is traveling through space what do you see with the interference patterns? a wave. This is the wave particle duality to my simple mind.

can you picture that?

I can picture almost anything in a way that makes sense to me....but whether it actually does make sense, that's a question for smarter people than me. I am hoping I'm like an idiot savant in a minor way and not just an idiot.

 

[mythx]

How could you perform an experiment to determine the validity of your hypothesis? Sounds like a possibility actually, and could explain why EM energy behaves both as a wave, and a particle. I guess the next question, is what's the size of one of these cogs? Or do cogs change size depending on wavelength?

 

[Mee_n_Mac]

imagine you have a box on the floor and it's full of little ping pong balls and somehow you could impart energy into one in the center of them all making it spin, if you could do that and watch it, after a few seconds the center ball would turn the rest like little cogs and the box full of ping pong balls would undulate and look like it had come alive, it would develop a wave pattern.

now imagine you could somehow impart a forward force as well as a spin to the balls, imagine that. It would look like a 3D wave traveling through the box. Now imagine the whole room is full of those little balls and you were able to continue imputing energy and spin into one ball after another and sending it through the room completely filled with the balls. Eventually every ball in the room would have turned as the energy from the single balls you input the initial charges of spin and forward force traveled across the room. Can you imagine that?

well, imagine that the ball you put spin into is the electron and the rest of the balls are space, in fact without your spin/charge the room is filled with balls without energy and undetectable. The nearest balls to the electron spin with residual charge and give the electron a sort of fuzzy indeterminate boundary, it's uncertain where the electron ends and space begins.....because since space is turning with the charge it appears fuzzy without a border or solid edge and it doesn't have one.

now, imagine that you put the double slit experiment set up in this room, your initial electron goes through and makes one stripe, but eventually the residual effect of the spin on space, the little spheres, makes it appear eventually as if more than one electron were present as two slits create an interference pattern, this is due to space spinning along side the electron charge/spin.

imagine you put a target in front of your electron, it would receive the impact of your actual spin/charged electron with the forward direction as if a particle hit it, compared to the residual almost undetectable spin on the rest of the balls, spheres, strings, it would appear like a lone particle striking the target, but when you look to see what is traveling through space what do you see with the interference patterns? a wave. This is the wave particle duality to my simple mind.

I've culled the above from your post just to focus upon for the moment. I can imagine your box of travelling spinning balls but I don't see a wave pattern in it. There may be some pattern but it's relationship to a classical EM wave propagating through space is lost to me. As for your dual slit explanation ....

Let's remember what's seen with the dual slit experiment. One particle (an electron if you will) is sent towards the slits at a time with a long time between each particle. Perhaps it makes it through one or the other slot and perhaps it doesn't. For those that do a single hit is recorded at a definite position on the target screen / detector. The "interference" pattern doesn't form until many, many hits have been recorded. Your explanation has me imagining that the pattern is seen after just one particle. Where have I gone astray ?

 

[SpeedFreek]

You have a good enquiring mind there!

I did not know that. Hubble time is simply the rate of expansion today run in reverse gets you an age for the Universe, but that would only be accurate if the expansion is actually constant and I don't believe it is. I say I don't believe it because there is an Inflationary theory that says it wasn't constant back near the beginning, if there really was a beginning and it's increasing now, so there's no reason really to even think of a constant, it should be thought of as more of an average, Hubble's average......

You are thinking along the right lines there...

anyway, if you attained a velocity through space equal to the rate of expansion then for you time should stop....I think. I think if you reached that velocity then you could go all over the Universe and no time would pass for you at all. The Universe would age through time passage but for you no time would pass at all, I think.

I am not sure what you mean by a velocity that is equal to the rate of expansion. The rate of expansion is expressed as something around 70 kilometers per second, per megaparsec. 70 kilometers per second is not particularly fast in relativistic terms (the speed of light is around 300,000 km/s). But what do you mean when you talk of a velocity through space equal to 70 (km/s)/Mpc ?

but, maybe the Universe isn't expanding at all, maybe Dark Matter around the Galaxy somehow drags light waves and they all lose energy and become red shifted? Maybe the Dark Matter absorbs energy but does not emit it and so it robs light of energy and lengthens its wave length.....could that happen?

It would have to rob the photon of its energy without changing its momentum, for that to work, otherwise objects would increasingly blur over increasing distance. And you also need to explain the time-dilation of the light from distant objects. A local effect of increasing the wavelength of photons cannot cause a gradual increase in the distance between those photons, they would simply scatter, otherwise how do you explain the gradual increase in the effect as the "train" of photons passes through the dark matter, gradually spacing them farther apart? If every photon in the image from a distant supernova interacts with dark matter in the same way, how do they get spaced out? If the interaction is random, how do they remain coherent?

Imagine a "train" of 6 photons, emitted over 1 second. They are 0.2 seconds apart:
0 - 0.2 - 0.4 - 0.6 - 0.8 - 1.

Send them through a "particle" of dark matter, and describe how that particle can double the length of that "train" of photons in such a way that they are emitted as:
0 - 0.4 - 0.8 - 1.2 - 1.6 - 2.

Each photon has to be delayed by an increasing length of time. How does your particle know how, and when, to do this, to any light that passes through?

 

[Boilermaker]

"Your explanation has me imagining that the pattern is seen after just one particle. Where have I gone astray ?"

hello me_n_mac,

if you can imagine the center ball spinning, it would turn the other balls around it, if the ball we put force into is spinning clockwise then the balls directly in contact with it will spin anticlockwise and so on, this is where it would start to undulate, the box would look like it came alive, you wouldn't see the whole wave pattern because of the box, all you'd see is what looks like the balls churning.................you have to use your imagination........also, for me to imagine it I had to incorporate strings which I am not sure the properties of, but I think they may be part of reality from the little I have read and they could make up space.........in my imagination. I know that the theory says the strings vibrate at different energies and depending on the energy you get certain particles. I am picturing space itself as strings curling up and conducting energy along, as the one in which the energy is concentrated in my example spins clockwise so the next ones are spun anticlockwise and this Eventually spins all the little strings in the room and so Eventually causes the interference pattern.

If my mental picture were correct though, you might get an interference pattern on the ceiling if you put the target there for long enough. What I am picturing is that we are swimming in a sea of these, space is made of these, there is no getting away from them. I am also thinking now that there couldn't be any way to detect them as they probably wouldn't have any charge of their own which I picture as spin direction............I am thinking that you could determine the size of them by the smallest possible electron shell or wavelength...........if the smallest shell and the smallest wavelength are the same or some obvious fraction of each other, then I think someone smarter than me could tell us the size of them. If the wave is caused by one turning the next ones and so on then there ought to be a way to calculate the diameter of the wave/particle............don't you think?

another thought I have is that if the force which is spinning the strings is not exactly constant or it somehow oscillates or if the strings aren't uniform in their size or if they don't curl up perfectly, if any of these things were true then the spin would be more like a wobble and the edge of the spinning string/cog thingmabob would not appear fuzzy and it could cause the uncertainty principle to come about........maybe, what do you think?

 

[Boilermaker]

Hello speedFreek

I am not sure what you mean by a velocity that is equal to the rate of expansion. The rate of expansion is expressed as something around 70 kilometers per second, per megaparsec. 70 kilometers per second is not particularly fast in relativistic terms (the speed of light is around 300,000 km/s). But what do you mean when you talk of a velocity through space equal to 70 (km/s)/Mpc ?

This is where smarter people than me have to tell me what's what. I have read that as we approach the speed of light that time slows to a complete stop. I am not sure why they say that but they seem to think that if you could exceed the speed of light that travel back in time would be possible, maybe.............you must have read this?

the reason why I am saying the velocity of the Hubble constant (or parameter) is because that is the speed the Universe is supposedly expanding, it's space that is expanding and it's the expansion of space that I am thinking is Time. So, I imagine that when we reach some rate less than infinite, we will not experience the passage of time and we could leave Earth on a ship (imaginary) travel at this critical speed whatever the exact rate is and we could travel across the entire Universe for ever and experience no time passage, for us. But, I have not yet tried to imagine what that would be like for us.......and you might tell me something which gets me thinking completely differently, I can only use what little I have heard or read and its not enough.

but that is why I mentioned that rate. I know that the Hubble is slow, I read that last night too, the same rates you just noted.

but, maybe the Universe isn't expanding at all, maybe Dark Matter around the Galaxy somehow drags light waves and they all lose energy and become red shifted? Maybe the Dark Matter absorbs energy but does not emit it and so it robs light of energy and lengthens its wave length.....could that happen?

It would have to rob the photon of its energy without changing its momentum, for that to work, otherwise objects would increasingly blur over increasing distance. And you also need to explain the time-dilation of the light from distant objects. A local effect of increasing the wavelength of photons cannot cause a gradual increase in the distance between those photons, they would simply scatter, otherwise how do you explain the gradual increase in the effect as the "train" of photons passes through the dark matter, gradually spacing them farther apart? If every photon in the image from a distant supernova interacts with dark matter in the same way, how do they get spaced out? If the interaction is random, how do they remain coherent?

I was thinking and it was a new thought too, that maybe the dark matter which our Solar system appears embedded in, can have an affect on the Wavelength of the light making it redshifted but not because of distance but because of something to do with light passing through the dark matter...........that thought was saying that maybe the Universe isn't expanding at all and everything else I think is rubbish.........maybe the Dark Matter has an effect on light, water and Gravity does, so maybe Dark Matter does too and the Universe isn't expanding the light is redshifted everywhere we look because everywhere we look we are looking Through Dark Matter Lenses....see what I mean?

Imagine a "train" of 6 photons, emitted over 1 second. They are 0.2 seconds apart:
0 - 0.2 - 0.4 - 0.6 - 0.8 - 1.

Send them through a "particle" of dark matter, and describe how that particle can double the length of that "train" of photons in such a way that they are emitted as:
0 - 0.4 - 0.8 - 1.2 - 1.6 - 2.

Each photon has to be delayed by an increasing length of time. How does your particle know how, and when, to do this, to any light that passes through?[/quote]

all I can say is that I have to read more about Dark Matter and Dark Energy, I was not thinking the photon passed through a particle of dark matter, I was thinking more along the lines of...................Dark Matter may be a Sea of Strings which for some reason does not transmit energy as efficiently as the strings in our Visible matter and light Universe. It could be that the Dark Matter is a Sea of smaller or larger strings, somehow denser and less efficient or maybe it's something altogether different, I will have to think about it and see if I can picture it somehow that it makes some sort of sense.

do you think it all has to make sense somehow? I do. I think that we ought to be able to make sense of the Universe and all the interactions that go on...............I don't buy virtual particles coming from "nothing" any more than I buy an actual particle coming from nothing or that the results of the double slit experiment are somehow mysterious or due to a parallel Universe, which I've heard a scientist suggest for the reason behind the results. I think that there is an unbroken chain of relationships between all the forces and particles that make up the Universe and us, somehow us too.

 

[DrRocket]

.....
But we speak of time as if it could somehow be separated from the three visible space dimensions, like width or depth is.
.....
of course, I might just be nuts.

I have no idea what you mean when you equate time to the expansion of space.

However, you are correct in your skepticism about the ability to separate time from space. That is the lesson of general relativity. Time and space and merely creations of arbitrary coordinate systems on a 4-dimensinal space-time manifold. In reality there is no way to globally separate time from space, the curvature of space-time irreversibly mixes them together.

 

[kg]

However, you are correct in your skepticism about the ability to separate time from space. That is the lesson of general relativity. Time and space and merely creations of arbitrary coordinate systems on a 4-dimensinal space-time manifold. In reality there is no way to globally separate time from space, the curvature of space-time irreversibly mixes them together.

I don't understand what is ment by space-time being curved or why the curvature mixes them together. I'm assuming that it's not curved in the same way that I normaly think of something being curved. What is it curved in relation to?

 

[Boilermaker]

.....
But we speak of time as if it could somehow be separated from the three visible space dimensions, like width or depth is.
.....
of course, I might just be nuts.

I have no idea what you mean when you equate time to the expansion of space.

However, you are correct in your skepticism about the ability to separate time from space. That is the lesson of general relativity. Time and space and merely creations of arbitrary coordinate systems on a 4-dimensinal space-time manifold. In reality there is no way to globally separate time from space, the curvature of space-time irreversibly mixes them together.

who am I to disagree with that? but, there have been experiments done which involved atomic clocks and motion through space at varying rates which determined that one clock experienced a difference in time passage from the other. There was no difference in the distance between the two points in space which determined the journey's length through space, only in the measured time of it. One clock was flying at velocity through space and one standing stationary on the ground and they recorded time passing at a different rate from each other.

So, what I understand from this is that time is relative to the Motion of the observer through space. Distance is not relative and C or velocity through space is not relative, only time measurement between the points is.

I do believe (but could be convinced otherwise with evidence and I'm open to that) that the reason time is relative is because what we call time and experience as time and which is relative to velocity through space, is the expansion OF space itself. It is my belief that you cannot separate time from space because you cannot separate the expansion from space, but you can alter your experience of it from someone else by adding velocity or gravity.

I know this might be difficult to imagine for some, but as space expands I believe everything in it expands also. I don't mean I believe an electron expands or a proton or neutron or any of those particles but the space between them in matter expands. I don't imagine that space expands around us but not in us. So, I believe it would be impossible to measure the expanding space with my ruler as my ruler is expanding with space.

I'm thinking of using this as an excuse for why I've become so large lately, it's not me it's the expansion of space, yeah, that's it, there's no obesity epidemic it's just that now we've expanded the the average lifespan by so much that we are all expanding with space................hahaha! but alas, I cannot use that as I've just said.........my tape and so my scale must also expand and that would keep it all relatively the same while I seem to have grown faster than my clothes.....drat! curse this space expansion obesity conundrum!

 

[DrRocket]

However, you are correct in your skepticism about the ability to separate time from space. That is the lesson of general relativity. Time and space and merely creations of arbitrary coordinate systems on a 4-dimensional space-time manifold. In reality there is no way to globally separate time from space, the curvature of space-time irreversibly mixes them together.

I don't understand what is meant by space-time being curved or why the curvature mixes them together. I'm assuming that it's not curved in the same way that I normally think of something being curved. What is it curved in relation to?

"Curved" means curved in the sense of differential geometry, which means that the curvature tensor for the manifold of space-time is something other than zero. This is actually a rather subtle concept, and while related to the radius of curvature for curves, which you might have seen in an elementary calculus class, is much more difficult to describe. The development of the notion of curvature for 2-dimensional surfaces was a major triumph for Gauss, one of the greatest mathematicians of all time and the extension to dimensions beyond 2 was a triumph for Bernard Riemann, another of the all-time greats and a student of Gauss.

Curvature manifests itself in things like the number of degrees in the interior angles of a triangle or the surface area of a sphere, which are different in curved geometries than in flat Euclidean geometries. It also affect the ability to find a global coordinate system. Since the usual coordinates for space-time are time and the 3 spatial dimensions, the effect is that there does not exist a global notion of time or of space. The coordinates are mixed together on large scales.

One example is the sphere. Locally you have a two-dimensional coordinate system. At most locations it is just latitude and longitude. But it does not work a the poles. So to have a two dimensional coordinate system you have to work in little patches, patches that are locally like little planes. There is no single coordinate system that will work everywhere. The same thing applies to space-time. What we call space and time is the result of local coordinates that cannot be extended to cover the entire space-time.

And even in local coordinates near massive bodies, what we call space is highly curved.

 

[DrRocket]

who am I to disagree with that? but, there have been experiments done which involved atomic clocks and motion through space at varying rates which determined that one clock experienced a difference in time passage from the other. There was no difference in the distance between the two points in space which determined the journey's length through space, only in the measured time of it. One clock was flying at velocity through space and one standing stationary on the ground and they recorded time passing at a different rate from each other.

What you are describing is correct in the Special Theory of Relativity. But Special Relativity is, well, "special". It applies only to observers in inertial reference frames, which are therefore in uniform linear motion with respect to one another, and it only applies in the absence of gravity. Even in special relativity, the events that one observer sees as simultaneous are different from what another sees as simultaneous unless those observers are at rest relative to one another. There is a spatial dependency in the relationship of time in the two reference frames, described by the Lorentz transformation. You often are not introduced to the full Lorentz transformation in a first course in modern physics that treats the special theory in one dimension.

http://en.wikipedia.org/wiki/Special_relativity

So, what I understand from this is that time is relative to the Motion of the observer through space. Distance is not relative and C or velocity through space is not relative, only time measurement between the points is.

But distance IS relative, and that is reflected in what is commonly called "length contraction" which is a counterpart to dime dilation.

In addition, when you go to general relativity and consider gravitation, the transformation becomes more complicated. There is no longer the universal reference frame of special relativity but only local coordinate systems with limited applicability or "range". See the previous post. General relativity also shows that clocks located at points of different gravitational potential will differ from one another. Clocks at lower potential (closer to the massive object) run slower. This has been confirmed in laboratory experiments, one at Harvard measuring the difference between clocks at different heights, the Pound-Rebka experiment.

http://en.wikipedia.org/wiki/Gravitatio ... e_dilation

http://en.wikipedia.org/wiki/Pound-Rebka_experiment

I do believe (but could be convinced otherwise with evidence and I'm open to that) that the reason time is relative is because what we call time and experience as time and which is relative to velocity through space, is the expansion OF space itself. It is my belief that you cannot separate time from space because you cannot separate the expansion from space, but you can alter your experience of it from someone else by adding velocity or gravity.

The inability to separate time from space is not directly related to the "expansion of space", but is simply due to the nature of curved manifolds. If space-time-were flat then you could determine global coordinates and separate the two.

I know this might be difficult to imagine for some, but as space expands I believe everything in it expands also. I don't mean I believe an electron expands or a proton or neutron or any of those particles but the space between them in matter expands. I don't imagine that space expands around us but not in us. So, I believe it would be impossible to measure the expanding space with my ruler as my ruler is expanding with space.

It is not difficult at all to imagine. It is just wrong.

What happens is that as space expands, a small tensile stress is exerted on mass within it. That tensile stress is resisted by the normal forces of physics -- the strong weak, electromagnetic and gravitational forces. The net result is that there is little effect within massive bodies. You are fractionally taller than you would be without the expansion, but the expansion is in equilibrium with the restoring forces and you are not growing as a result of expansion.

I'm thinking of using this as an excuse for why I've become so large lately, it's not me it's the expansion of space, yeah, that's it, there's no obesity epidemic it's just that now we've expanded the the average lifespan by so much that we are all expanding with space................hahaha! but alas, I cannot use that as I've just said.........my tape and so my scale must also expand and that would keep it all relatively the same while I seem to have grown faster than my clothes.....drat! curse this space expansion obesity conundrum!

Nice try.

 

[Mee_n_Mac]

"Curved" means curved in the sense of differential geometry, which means that the curvature tensor for the manifold of space-time is something other than zero. This is actually a rather subtle concept, and while related to the radius of curvature for curves, which you might have seen in an elementary calculus class, is much more difficult to describe. The development of the notion of curvature for 2-dimensional surfaces was a major triumph for Gauss, one of the greatest mathematicians of all time and the extension to dimensions beyond 2 was a triumph for Bernard Riemann, another of the all-time greats and a student of Gauss.

Curvature manaifests itself in things like the number of degrees in the interior angles of a triangle or the surface area of a spherre, which are different in curved geometries than in flat Eudlidean geometries. It also affect the ability to find a global coordinate system. Since the usual coordinates for space-time are time and the 3 spatial dimensions, the effect is that there does not exist a global notion of time or of space. The coordinates are mixed together on large scales.

One example is the sphere. Locally you have a two-dimensional coordinate system. At most locations it is just lattitude and longitude. But it does not work a the poles. So to have a two dimensional coordinate system you have to work in little patches, patches that are locally like little planes. There is no single coordinate system that will work everywhere. The same thing applies to space-time. What we call space and time is the result of local coordinates that cannot be extended to cover the entire space-time.

And even in local coordinates near massive bodies, what we call space is highly curved.

That's a nice simple explanation (emphasis added by me) !

 

[Boilermaker]

who am I to disagree with that? but, there have been experiments done which involved atomic clocks and motion through space at varying rates which determined that one clock experienced a difference in time passage from the other. There was no difference in the distance between the two points in space which determined the journey's length through space, only in the measured time of it. One clock was flying at velocity through space and one standing stationary on the ground and they recorded time passing at a different rate from each other.

What you are describing is correct in the Special Theory of Relativity. But Special Relativity is, well, "special". It applies only to observers in inertial reference frames, which are therefore in uniform linear motion with respect to one another, and it only applies in the absence of gravity. Even in special relativity, the events that one observer sees as simultaneous are different from what another sees as simultaneous unless those observers are at rest relative to one another. There is a spatial dependency in the relationship of time in the two reference frames, described by the Lorentz transformation. You often are not introduced to the full Lorentz transformation in a first course in modern physics that treats the special theory in one dimension.

http://en.wikipedia.org/wiki/Special_relativity

So, what I understand from this is that time is relative to the Motion of the observer through space. Distance is not relative and C or velocity through space is not relative, only time measurement between the points is.

But distance IS relative, and that is reflected in what is commonly called "length contraction" which is a counterpart to dime dilation.

correct me if I'm wrong, but from what I just read about the contraction, that applies to an object in motion through space at high portions of the speed of light from an observer viewing the object, is that right?

so, that is not a variance in the distance in space but on a body in motion through space and, as that body is at such a high rate of speed then according to my idiot savant brain, the time that passes for the observer is more than the time which would pass for the object in motion and so what the observer witnesses is not a compression of length but what appears to be a compression in length due to a compression in time, on the object in motion, which he witnessed in one time frame......I have to assume that if the moving object were ship with an observer on it then what that observer would see would be the opposite or a lengthening of objects it passed, such as the other observer, is that right?

In addition, when you go to general relativity and consider gravitation, the transformation becomes more complicated. There is no longer the universal reference frame of special relativity but only local coordinate systems with limited applicability or "range". See the previous post. General relativity also shows that clocks located at points of different gravitational potential will differ from one another. Clocks at lower potential (closer to the massive object) run slower. This has been confirmed in laboratory experiments, one at Harvard measuring the difference between clocks at different heights, the Pound-Rebka experiment.

yeah, I had guessed that would be the case.........I have been imagining that Gravity slows the expansion and that velocity is equivalent to Gravity and Mass so any of these should slow time down without reducing space. (the distance between two points, as in a journey's start and end points, I mean)

http://en.wikipedia.org/wiki/Gravitatio ... e_dilation

http://en.wikipedia.org/wiki/Pound-Rebka_experiment

I do believe (but could be convinced otherwise with evidence and I'm open to that) that the reason time is relative is because what we call time and experience as time and which is relative to velocity through space, is the expansion OF space itself. It is my belief that you cannot separate time from space because you cannot separate the expansion from space, but you can alter your experience of it from someone else by adding velocity or gravity.

The inability to separate time from space is not directly related to the "expansion of space", but is simply due to the nature of curved manifolds. If space-time-were flat then you could determine global coordinates and separate the two.

I know this might be difficult to imagine for some, but as space expands I believe everything in it expands also. I don't mean I believe an electron expands or a proton or neutron or any of those particles but the space between them in matter expands. I don't imagine that space expands around us but not in us. So, I believe it would be impossible to measure the expanding space with my ruler as my ruler is expanding with space.

It is not difficult at all to imagine. It is just wrong.

What happens is that as space expands, a small tensile stress is exerted on mass within it. That tensile stress is resisted by the normal forces of physics -- the strong weak, electromagnetic and gravitational forces. The net result is that there is little effect within massive bodies. You are fractionally taller than you would be without the expansion, but the expansion is in equilibrium with the restoring forces and you are not growing as a result of expansion.


sometimes I'm fooling around here, in my imagination I picture time lapse photographs of a new barn eventually peeling paint off and the door falling off and then old and just aging into an old barn and all the while it's because those minute but strong bonds are being stretched just an almost infinitely small amount over the years and so things age and fall apart due to the stresses. If we join two different metals together you can get a little reaction which isn't good for the metal over time.......I've seen those videos where the plates are separated and arcs come from out of thin air....I picture this going on between our atoms all the time as we age, and the same with all atoms, car atoms, house atoms, whatever...........the bonds are stretched and this takes it's toll...........in my imagination at least.

I'm thinking of using this as an excuse for why I've become so large lately, it's not me it's the expansion of space, yeah, that's it, there's no obesity epidemic it's just that now we've expanded the the average lifespan by so much that we are all expanding with space................hahaha! but alas, I cannot use that as I've just said.........my tape and so my scale must also expand and that would keep it all relatively the same while I seem to have grown faster than my clothes.....drat! curse this space expansion obesity conundrum!

Nice try.

yeah, I actually think it began with the introduction of fructose into the diet back in the eighties...........but that might not be right............cheap sweetener.

 

[Boilermaker]

in the illustrations at this web page: http://en.wikipedia.org/wiki/Relativity_of_simultaneity the simultaneity is supposedly shown to be relative by the bottom of the two diagrams. But, it's quite obvious that the source in the top diagram is in the middle of the two trains and the light photon's journey is equal to both trains through time......but in the bottom one, the train on the right moves away from the source while the one on the left moves toward it through time....by that I mean, one moves closer to the middle while the other moves further away and so one train comes closer while the other further...............

that's nothing to do with relativity......everything to do with geometry....am I wrong?

the source of the light is midway between the two trains on the bottom line. the two trains go straight up away from the bottom line and the light is emitted from the center point on the bottom line at forty five degree angles and intersects the two trains at the same time and at the same level up the tracks.........in the second picture the light source is the same and it emits it's lights at forty five degree angles while the trains change course compared to the first set and now the distance is closed between one train and the source and opened between the other........if the light source was also turned on the bottom line to reflect the new angle that the trains are taking then the intersection time and place will be simultaneous and even....just like in the first picture.

 

[SpeedFreek]

The relativity of simultaneity.

You are sitting in the middle of a train carriage as it approaches a station. The train is going to go through the station without stopping.

You turn on a light in the centre of the carriage, and you see the light hit both ends of the carriage at the same time.

Someone on the platform sees the light turn on in the centre of the carriage as the train passes by. They see the light hit the rear wall of the carriage before it hits the front of the carriage, because although the train is moving relative to them, the speed of light is constant, relative to them.

So, did the light hit both ends of the carriage at the same time, or not?

 

[atlantisworp]

No is not

 

[atlantisworp]

Time is just a ridiculous human invention. We, aliens don’t think that way.
When someone in the past, realized that anything around, including himself was getting older to finally cease existing, time measure was invented. The universe use a larger scale of time fraction, but in any case is simple a vast method to understand changing’s to huge amounts of energy. When that energy will finally be exhaust the hit will end and the cold will remind. Then some of us as dreams will still be there, incorporeal and for ever. For that, time do not really exist.

 

[SpeedFreek]

No is not

But the observer in the centre of the carriage sees the light hit both ends at the same time. The light definitely hits the ends of the carriage at the same time, from his point of view.

However, the light definitely does not hit both ends of the carriage at the same time, from the point of view of the observer on the platform.

So, who is correct? The observer in the train? The observer on the platform? Neither of them? Both of them?

 

[SpeedFreek]

Time is just a ridiculous human invention. We, aliens don’t think that way.
When someone in the past, realized that anything around, including himself was getting older to finally cease existing, time measure was invented. The universe use a larger scale of time fraction, but in any case is simple a vast method to understand changing’s to huge amounts of energy. When that energy will finally be exhaust the hit will end and the cold will remind. Then some of us as dreams will still be there, incorporeal and for ever. For that, time do not really exist.

You just said:

Time was invented by man, when he worked out how to time the passage of events, or entropy. When the universe has reached a maximum state of entropy, time will become meaningless.

When man worked out how to time the passage of events, he didn't invent time, he simply defined it. The passage of events has been happening since the beginning of the universe and it is that which we choose to call time. It is not a ridiculous human invention - all we invented is a very useful way to quantify the passage of events.

Things would still happen in the universe if mankind had never existed. Time would still pass.