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If time is not a dimension of reality, then how do you explain hundreds of thousands of experiments that show that motion in the spacial dimensions slows down motion in the time dimension. The faster you travel ghrough space, the slower time passes for you relative to to someone who is stationary or traveling slower then you through space.

I think you are responding to avg but I consider the premises behind your question to be faulty,and they rest on improper definitions of "time","dimension","space" being used so often in relation to physics.

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I think you are responding to avg but I consider the premises behind your question to be faulty,and they rest on improper definitions of "time","dimension","space" being used so often in relation to physics.

If I have improper defenitions that would mean that I do not know what the words mean, or at least not in the same way as you. This is a huge barrier in our ability to communicate with each other since the words I say mean somethign different to you. So please what are the proper defenitions so I can communicate wit you?

Meanwhile I will refrase the question.

How do you explain a particle such as a muon, which has a certain life span, and is traveling at a certain speed. At the speed it is traveling and the life span that it has, traveling from the top of earth's atmosphere toward the earth it should not even make it a fraction of the way before it diseapers, however it makes it all the way the surface.

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Because if nothing exsisted between matter, then all matter would be touching.

Arrgh. This argument, and others like it have been bugging me for weeks. I'm working on a post to discuss it...

This is a reification of space as some primary feature of reality. Distance is a relationship. To say that objects A and B are 1 meter apart, means that the distance relationship between them has a value of 1 meter. It does not literally mean there is 1 meter of nothingness between them that must be filled either discretely or continuously in order not to violate "Existence exists."

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Because if nothing exsisted between matter, then all matter would be touching.
You're not answering the question I asked or Thomas, you're addressing a totally different question (one which I have yelled at Thomas before, and to quote Jake, arrgh). How does that have anything to do with the concept "dimension", and why does the concept "dimension" not apply equally well to time.
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Arrgh. This argument, and others like it have been bugging me for weeks. I'm working on a post to discuss it...

This is a reification of space as some primary feature of reality. Distance is a relationship. To say that objects A and B are 1 meter apart, means that the distance relationship between them has a value of 1 meter. It does not literally mean there is 1 meter of nothingness between them that must be filled either discretely or continuously in order not to violate "Existence exists."

If spacesial dimensions are not real, then why experiments show that lengths and distances change depending on how fast you are traveling?

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You're not answering the question I asked or Thomas, you're addressing a totally different question (one which I have yelled at Thomas before, and to quote Jake, arrgh). How does that have anything to do with the concept "dimension", and why does the concept "dimension" not apply equally well to time.

oh, I am sorry. I am misunderstanding your questions, or arguments. My belief is that space and time, or more accuratly spacetime exsists as in its a physical entity. You can observe its effects on us and reality and vice versa. I don't think space and time just tools of our brain, I don't believe that they just exsist in our conciousness.

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Space and Time are two different "types" of dimensions. From experiments and (theory) space and time are one entity in which matter exists.

To say that space and/or time is just a construct designed to deal with movement is trivial. It's akin to saying that velocity doesn't exist, it's just a product of momentum and mass. You need a certain number of fundamental independent variables and as far as we know, that number is four.

This isn't to say that higher dimensions cannot exist. There are many theories of physics (none which have been accepted as real yet) which rely on the concept of higher dimensions. Many concepts can be easier to explain as being in 5 dimensions or more. These dimensions, however, are considered to be too small to detect in regular experience. For example, if you were walking on a row of cylinders, you may not notice them if the cylinders are very very small. But an ant or a small particle would have to travel across it's (half) radius and for it there would be that one more "dimension".

Here's the catch though: Since none of these dimensions have ever been measured, it's all just a theory. In physics, if it cannot be measured, it isn't real.

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Space and Time are two different "types" of dimensions. From experiments and (theory) space and time are one entity in which matter exists.

To say that space and/or time is just a construct designed to deal with movement is trivial. It's akin to saying that velocity doesn't exist, it's just a product of momentum and mass. You need a certain number of fundamental independent variables and as far as we know, that number is four.

This isn't to say that higher dimensions cannot exist. There are many theories of physics (none which have been accepted as real yet) which rely on the concept of higher dimensions. Many concepts can be easier to explain as being in 5 dimensions or more. These dimensions, however, are considered to be too small to detect in regular experience. For example, if you were walking on a row of cylinders, you may not notice them if the cylinders are very very small. But an ant or a small particle would have to travel across it's (half) radius and for it there would be that one more "dimension".

Here's the catch though: Since none of these dimensions have ever been measured, it's all just a theory. In physics, if it cannot be measured, it isn't real.

Only IF the premises of Relativity are sound. I wish folks would ask themselves what the essential characteristics of the concept entity are.The part about extra dimensions to me is absurd and rest on not defining the word and using it consistently. Someone once said "Math seems to be the lubricant for hammer square pegs into round holes".

Edited by Plasmatic
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Only IF the premises of Relativity are sound. I wish folks would ask themselves what the essential characteristics of the concept entity are.The part about extra dimensions to me is absurd and rest on not defining the word and using it consistently. Someone once said "Math seems to be the lubricant for hammer square pegs into round holes".

What evidence leads you to believe that relativity is not sound?

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I don't know of any reason to believe that Relativity has higher dimensions. For that matter, none of the acceptable theories in physics involve any more than four dimensions (unless that's what you have a problem with).

I agree that the premise behind higher dimensions aren't necessarily correct. But to dismiss it as a whole isn't very scientific. If you can prove it, great. Or else it doesn't exist.

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If spacesial dimensions are not real, then why experiments show that lengths and distances change depending on how fast you are traveling?

Please read what I wrote. I didn't say that spatial dimensions are not real. I said that the existence of a non-zero distance relationship between two entities does not necessitate the presence of something existing between those entities, nor does it necessitate some medium through which the distance is measured.

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Space and Time are two different "types" of dimensions. From experiments and (theory) space and time are one entity in which matter exists.
oh, I am sorry. I am misunderstanding your questions, or arguments. My belief is that space and time, or more accuratly spacetime exsists as in its a physical entity. You can observe its effects on us and reality and vice versa. I don't think space and time just tools of our brain, I don't believe that they just exsist in our conciousness.
bold mine

Experiments do not show that spacetime (or space) is a physical entity. Experiments show that a massive entity affects the actions and relationships of oher entities in its vicinity (i.e. entities with a certain maximal distance relationship to the massive entity). These experimental results are not dependent on space existing as a physical entity with a warping geometry.

My Physics education ended with an upper-level undergraduate course, so I'll use the Wikipedia article on Background-Independence to explain:

The resolution to the hole argument (mainly taken from Rovelli's book) is as follows. As GR [General Relativity] does not determine the distance between spacetime points, how the gravitational and matter fields are located over spacetime, and so the values they take at spacetime points, can have no physical meaning. What GR does determine, however, are the mutual relations that exist between the gravitational field and the matter fields (i.e. the value the gravitational field takes where the matter field takes such and such value). From these mutual relations we can form a notion of matter being located with respect to the gravitational field and vice-versa, (see Rovelli's for exposition). What Einstein discovered was that physical entities are located with respect to one another only and not with respect to the spacetime manifold. This is what background independence is! And that is the context for Einstein's remark "beyond my wildest expectations".

The visualization of a warping spacetime is a means of describing the results of General Relativity to people (like me) who do not have the requisite mathematical knowledge to otherwise understand it. However, this visualization is not technically accurate, and should not be used to justify the reification of space as an entity.

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When forced to summarize the general theory of relativity in one sentence:

Time and space and gravitation have no separate existence from matter. ...

Physical objects are not in space, but these objects are spatially extended. In this way the concept 'empty space' loses its meaning. ... Since the theory of general relativity implies the representation of physical reality by a continuous field, the concept of particles or material points cannot play a fundamental part, ... and can only appear as a limited region in space where the field strength / energy density are particularly high. (Albert Einstein, 1950)

Is "matter" physical?If something is made of matter is it an "entity"? The answer will explain my comments about Relativity.

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Nonsense. Time is no more and no less a "mental human construct" than space, matter or movement. Where do you get your strange ideas about existence?

From Einstein's Relativity Theory. It is not easy to grasp.

Anyway, what we call "time" is only comparision with predicatble movements.

Like the earth rotating aorund its axis (1 day of 'time') or the earth rotating around the sun (1 year of 'time').

All "time" measures imply matter and movement.

Imagine that suddenly all movement stop. All, including particles and atoms. ¿Will time be 'passing'?

Imagine that suddenly all movement IS REVERSED. All, including particles and atoms. ¿Will time be RETROCEDING, like a movie in reverse?

In one of the Einstein's examples, an astrounaut leaves the earth and travels at near-light speed. When he returns to earth after 10 years (for him)

he find that 20 years have passed in Earth.

http://www.thespacesite.com/space_einstein...relativity.html

One explanation of the paradox, is that at near-light speed ALL MOVEMENTS are ralentized, because the extra energy required for -any- movement at near-light speed (including particles and atoms). Since MOVEMENT is ralentized, "time" (relative to the astronaut) is also ralentized, that's because what we call "time" is just movement. In Earth (at normal speed) things move "normally", so do "earth time".

All of this said. You can be an fully objectivist (like me) with time being just an useful "idea" and not something HARD-REAL like matter,space and movement.

I was not trying to promote subjetivism, just pointintg the different nature of "time".

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"Time doesn't exist in reality. In reality there is only matter and movement. Time is a mental human construction, a side effect of humans having memory."

Time is an existent but not an entity.[a "mental something''] One needs to be careful to use this word "exist" consistently.

Question, just to learn.

Anything that can be 'thinnked' is an 'existent' and 'exists' ?

Any "mental something'' exists ?

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You failed to explain why "space" isn't, by your criteria, a "mental construct".

Just by choice. I cannot -prove- to you that anything "exists". (solipsism is logically irrefutable),

I use my mind and reason and choose to believe the existence of an objetive external world which

is compossed of matter, space and movement. The perception of changes in this external world, specifically the

movements which are 'periodic', is what we call 'time', and it's an useful construct by wich we can anticipate other periodical

movements and attain rational world-related goals, but I do not see 'time' as something existent per-se like matter, space and mov.

Let's imagine an alien traveling trhu the solar system. He says: "at our current speed the third

planet will rotate 5 times before we land", He has no concept of time, and he do not need it to perceive and explain

the same real world out there.

Of course the concept/sensation/idea of time 'passing' it is useful and almost every human has the same concept incorporated.

Edited by Lucio
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Let's imagine an alien traveling trhu the solar system. He says: "at our current speed the third

planet will rotate 5 times before we land", He has no concept of time, and he do not need it to perceive and explain the same real world out there.

Please explain what seems to be an obvious contradiction here:

1) "...the third planet will rotate 5 times before we land."

2) He has no concept of time...

The concepts "before" and "after" are dependent on understanding "time". You may understand "before" and "after" without explicit knowledge of any units of time, but the measurement is still there to be made. In your example, it takes the alien 5 planet-rotations to land.

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Just by choice. I cannot -prove- to you that anything "exists".
I won't bother explaining why that is simply false. What I want you to do is explain what evidence you have that time is a "mental construct" in such a way that "space" isn't. Neither is an entity, both are existents. (I hope you understant the distinction between "existent" and "entity"). Both are higher-level abstractions built on tangibles.
I use my mind and reason and choose to believe the existence of an objetive external world which is compossed of matter, space and movement.
So you are claiming that it's a personal choice to believe in these three things, and not believe in time? What justifies not excluding space? What justifies including motion when motion is a relationship between an entity as a function of time and space?
Let's imagine an alien traveling trhu the solar system. He says: "at our current speed the third planet will rotate 5 times before we land", He has no concept of time, and he do not need it to perceive and explain the same real world out there.
Uh, your explanation was loaded with references to time. You better try again.
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What Einstein discovered was that physical entities are located with respect to one another only and not with respect to the space-time manifold.

This is not what Einstein discovered. Mach argued something like that. When Newton developed his equations he proposed an experiment, that from then on was known as Newton's bucket. He observed that water in a spinning bucket also begins to spin. He asked the question what if this was happening in an empty universe, universe with no matter. What is the water in the bucket spinning in relation to? I am not going to go into the details, but Newton concluded that the water was spinning in relation to absolute space. Later Mach made an argument against that. And at one point Einstein did write to Mach and said that he thinks that the stuff he is working on will prove Mach right. However, when Einstein finished special and general relativity he concluded that the water was spinning in relation to what he called absolute space-time.

Experiments do not show that space-time (or space) is a physical entity. Experiments show that a massive entity affects the actions and relationships of oher entities in its vicinity (i.e. entities with a certain maximal distance relationship to the massive entity). These experimental results are not dependent on space existing as a physical entity with a warping geometry.

The visualization of a warping space-time is a means of describing the results of General Relativity to people (like me) who do not have the requisite mathematical knowledge to otherwise understand it. However, this visualization is not technically accurate, and should not be used to justify the reification of space as an entity.

You failed to explain why "space" isn't, by your criteria, a "mental construct".

The warping geometry is not just something scientists use to explain things to us, it is actually what is happening. Einstein's equations are actually very simple.

If space and time are just a mental construct, as a consequence of humans having a memory, then all humans should then have the same memory, should all agree on the shape of things, and how much time elapsed. Though this seems to be true in everyday life, it is not what Einstein's equations show, and it is not what the experiments conducted to test Einstein's equations show.

Ex: Bob is standing at the train station, Mary boards the train which will pass the train station going at 50% of the speed of light. Mary is holding a meter stick, both Bob and Mary will measure the meter stick as the train passes the train station. Mary and Bob compare the results, Mary has 100cm, Bob has 50cm. If Mary and Bob aslo both had stop watches, Mary would of recorded that she was on the train for 30 seconds, while Bob would have recorded that she was on the train for 1 minute. These are the results of real experiments conducted in partical excellators. But Einstein predicted this even before any experiments where conducted. The reasoning in this prediction, is very simple, even mathematically. The equation for velocity is v=d/t. Einstein new at that time already that experiments show that the velocity of light is constant. Lets go back to the train except first at normal speeds. Mary is on train, train is going at 90 miles per hour, Mary throws a baseball at 30 miles per hour. Mary records the baseball speed at 30 miles an hour, Bob records it at 120 miles an hour. Now the train is going at 50% the speed of light, and instead of throwing a baseball Mary turns on a flashlight. Both Mary and Bob record the light emiting from flash light going at 186,000 miles per second. How can this be, how can both Mary and Bob record the same velocity. Einstein realized that since the v in the equation(v=d/t) must stay constant, that it means that the other side of the equation must be changing. The other side is d/t, distance and time.

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The warping geometry is not just something scientists use to explain things to us, it is actually what is happening.
So you agree that time and space are not fundamentally different in that one is real and the other is a mental construct. The latter is a particularly confused notion, IMO, in that it ignores the nature of concepts and their relationship to existents.
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  • 2 weeks later...
What about the idea of time being a 4th dimension.. not a spacial dimension, but a spatiotemporal dimension. Is that valid? Is it applicable to this question, or is it just a totally different context? What exactly does "dimension" mean, here?

Just define the word "dimension" and you're all set.

Dimension: Quality of an object indicating it has extent in one of three mutually perpendicular directions.

With this definition, "time" is not a dimension. You cannot move in the direction of time. If you go with a more mathematical definition then you can justify as many "dimensions" as you want by constructing independent vector bases. But then one must ask what this has to do with real objects.

Sorry, when I said 3 I was referring to spatial only. Sure, time as a 4th is valid I think, but I'm don't think that it also in any way implies a 5th.

I disagree very strongly. In fact, there is no reason to insert "time" into equations of motion at all. Motion is relational, i.e. the relationship between the locations of objects. When mathematicians say an object "is moving with respect to time" they are eschewing the physical nature of the situation in exchange for a mathematical convenience. They cannot say A is moving with respect to B until they point to A and B.

time: motion + observer

My opinion on this is simple. We don't know how many dimensions exist until we define the concept "dimension", and put the word "dimension" in context. If you are talking about how many dimensions exist in reality (that is, how many sides an object can have), the answer is 3 (height, length, and width).If you are talking about dimensions, as in a fancy rational database that I made for work, then the answer can be 10 (assuming that i made a 10 dimensional database!). Of course, I can come up with a lot of different examples, however, I trust you understand my point.

So what is a dimension exactly? I think thats a different debate (or thread).

Sounds very good. In physics, i.e. the study of objects that exist (*this* keyboard), all objects are three dimensional.

Here's a case where I think words are failing us. The three spatial dimensions are a valid concept, but the same is true of space-time. Unfortunately, the same word is used for both concepts., thanks to The Time Machine. There's no question that time exists in reality.

What do you mean by "exist in reality"? There is a fundamental difference between an object's dimensionality (its length, width, and height) and my experience of getting older, of before/after, etc. "Time" is dependent upon the conscious observer. When we remove the conscious observer there is no "time" thing lying around, there are only 3D objects at locations. Only when the conscious observer looks and says "A is moving twice as fast as B" or something similar, does the concept of "time" even arise.

There are only 3 spacial dimensions: it is an impossibility for a 4th line to be perpendicular to the origional 3 intersecting lines at the same time.

Dimension means a measurable aspect. For example, a thing can said to have 5 dimensions if one measures its heigth, width, length, mass, and temperature. Dimensions are measures of certain existents in reality.

Not just any word we utter or anything we can measure qualifies as a dimension. Dimension, at least in physics, has a very specific and unambiguous meaning. It refers to the quality of an object having extent in one of three mutually perpendicular directions. When we introduce the conscious observer s/he may conceptualize temperature, time, weight, etc. but these are in his/her head. Nature didn't "know" about them.

Time doesn't exist in reality. In reality there is only matter and movement. Time is a mental human construction, a side effect of humans having memory.

Exactly. It takes a conscious observer, with memory, to conceptualize "time". When we remove him/her there are only 3D objects changing location.

Nonsense. Time is no more and no less a "mental human construct" than space, matter or movement. Where do you get your strange ideas about existence?

Movement does not require the human mind. Motion is just two or more locations of an object. A human doesn't have to observe the object or measure the locations. If it was at two or more locations, it moved.

Space is "nothing", a 0. Matter is a shorthand term humans use for the sum total of all objects that exist.

Time is a conceptualization of motion or change; it doesn't exist outside the human mind as a type of substance which is needed for things to be able to move. One can say that given enough time, that super nova that exploded light years away about six billion years ago led to the creation of the solar system when its shock wave hit a cloud of gas and dust, but it is not as if time is a sort of energy source one must have in order to be able to move. In this sense it is a human mental construct, but it is based upon actual observations of things moving or changing centered around before and after, as Aristotle first recognized.

Say one tosses a ball at the wall, but it doesn't hit the wall because the pet dog grabbed it. Because we can conceptualize, we can form the concept of time by abstracting from this and other such events, and comparing it to a standard motion from which we can compare to all other motions. We say the dog got the ball before it hit the wall, or if it bounces off the wall and the dog grabbed it then we can say that happened after the ball hit the wall. Similarly, we can take a standard motion -- say the motion of a stop watch -- and use it to rate other motions as before and after the sweeping hand crosses a certain distance.

So, the concept of time is based upon observation, but we don't directly perceive time, what we perceive are things acting or changing, and we develop the concept of time from these observations.

I think what confuses some people is that we do have several mechanism like a clock and a stop watch in our heads that make it seem like we are observing the passage of time, when actually we are doing the same thing internally that we do when we look at a clock or a watch.

Time would not be a forth dimension, except figuratively, in the sense of one more parameter that can be measured.

Very well said :P.

If time is not a dimension of reality, then how do you explain hundreds of thousands of experiments that show that motion in the spacial dimensions slows down motion in the time dimension. The faster you travel ghrough space, the slower time passes for you relative to to someone who is stationary or traveling slower then you through space.

All the experiments in the world cannot change the definition of "dimension". Whether time is a dimension or not is not a matter of experiment or verification.

I propose time is a dimension.

My pendulum swung fewer times when I was running than when I was standing.

Therefore time is a dimension.

How will you "verify" if time is a dimension, if you do not even know what a dimension is!? You have to settle the definition first so we know what you're actually going to prove.

Which is entirely different from saying that time does not exist. Space also does not exist outside of the mind as a type of substance, and for that matter no attributes "exist as such, as entities, outside the mind". I find it very useful to recall what Rand had to say on the subject:

The building-block of man's knowledge is the concept of an "existent"—of
something that exists, be it a thing, an attribute or an action
.

and understand the source of people's confusion about the nature of things that exist -- the adherence to a very concrete understanding of existent by limiting it to what children are first aware of:

The first stage is a child's awareness of objects, of things—which represents the (implicit) concept "entity."

This adherence to child-like epistemology explains why many people are confused about the difference between entity and existent.Why would you think that the other three so-called dimensions are dimensions, except also figuratively?

Length, width, and height are ubiquitous and self-evident attributes of every object we observe. Where is time? Can you point in its direction? Can you point at it? A picture of it?

When you think about the issue critically you realize that "time" is a mental conception of the relative motion of objects. We pick a standard mover and say everything else is moving X much faster or slower than it. We can then say something takes 1/X "time units" to go a unit distance.

How do you explain a particle such as a muon, which has a certain life span, and is traveling at a certain speed. At the speed it is traveling and the life span that it has, traveling from the top of earth's atmosphere toward the earth it should not even make it a fraction of the way before it diseapers, however it makes it all the way the surface.

If the physicist cannot even imagine or illustrate a muon, let alone point to it, then s/he has nothing. All the measurements in the world do not make up for an arbitrary and/or nonexistent hypothesis. Without this crucial step the word "muon" remains a Joker and all statements based on it are arbitrary.

Assuming the physicist can get past this hurdle, now s/he will have to explain the physical process of muon decay, since his/her theory is based on it. What causes the decay? If s/he cannot explain this process then s/he cannot possibly draw meaningful scientific conclusions from experiments based on it.

Assuming the physicist can get past this , at best s/he has shown that the physical processes governing muon decay are altered at high velocity.

As long as decay processes are treated as random physicists cannot even begin to base conclusions so fundamental as "time is a dimension" on decay experiments.

You're not answering the question I asked or Thomas, you're addressing a totally different question (one which I have yelled at Thomas before, and to quote Jake, arrgh). How does that have anything to do with the concept "dimension", and why does the concept "dimension" not apply equally well to time.

The reason the concept "dimension" does (or does not) apply to time depends solely on the definition of "dimension". There is the physics definition, which I stated, and there is the mathematical definition. In mathematics "dimensions" are essentially anything you can measure but can't equate mathematically to another measurable. This seems highly arbitrary and rationalistic to me. It also seems a little dishonest since those reading mathspeak outside the field are generally thinking about physical dimensions.

If spacesial dimensions are not real, then why experiments show that lengths and distances change depending on how fast you are traveling?

Distance doesn't change with perspective. Distance-traveled changes with perspective. Distance is a static concept. In relativity and most measurements you are NOT measuring the static concept "distance" between the floor and ceiling of the train but the dynamic concept "distance-traveled by a photon" from the floor to the train. It seems this misconception is nearly universal and inevitably leads to misunderstanding.

An object can, of course, expand or contract under various circumstances for a variety of reasons.

I measure a brick and a block of metal, concluding the metal is longer than the brick. You measure them and conclude the brick is longer than the metal. I measured on a summer afternoon and you measured on a January night. Do we suddenly conclude that time or temperature are dimensions? Of course not! We formulate a hypothesis (atoms perhaps) and a theory that atoms stick together, some more than others. When the atoms are moving fast they loosen from their stickiness and have a greater distance between each other. Metal atoms bind less rigidly so, when they move faster (are heated), they slip and slide away from each other more than in the rigid binding of brick.

So if a pendulum seems to swing fewer times when you're running you don't conclude time is a dimension. This is at best a restatement of what happened, not an explanation! That the clock swung fewer times is just an observation. What's the scientific theory/explanation? Time dilated? If you cannot point to time this "theory" is a non-starter.

Space and Time are two different "types" of dimensions. From experiments and (theory) space and time are one entity in which matter exists.

No amount of experimentation in the world will suddenly make my keyboard 4D. It is clearly and unambiguously 3D.

To say that space and/or time is just a construct designed to deal with movement is trivial. It's akin to saying that velocity doesn't exist, it's just a product of momentum and mass. You need a certain number of fundamental independent variables and as far as we know, that number is four.

The product of momentum and mass is just m^2*v, so not sure what this means.

Time is a convenient paramter to use when dealing with the motion of many objects. If we have only three objects A, B, and C we can just describe their relative motion directly, using only their relative location:

AC = 2*BC

i.e. A is moving twice as fast as B.

If we have many objects this becomes more difficult, so we let everything move "with respect to time". This is essentially laying down a universal standard for everything's motion, so that we don't have to deal with purely relational motion anymore. Since physics has never found a "preferred frame" i.e. a preferred standard in Nature, the correct physical representation is purely relative motion with no "respect to time" while inserting "time" is a mathematical convenience.

This is not to deny everyone's everyday experience/conceptualization of "time". However this is more a subject of philosophy than physics. Physics seeks to understand purely the physical situation, i.e. the objects. Philosophy seeks to study concepts like consciousness and the mind.

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This isn't to say that higher dimensions cannot exist. There are many theories of physics (none which have been accepted as real yet) which rely on the concept of higher dimensions. Many concepts can be easier to explain as being in 5 dimensions or more. These dimensions, however, are considered to be too small to detect in regular experience. For example, if you were walking on a row of cylinders, you may not notice them if the cylinders are very very small. But an ant or a small particle would have to travel across it's (half) radius and for it there would be that one more "dimension".

Here's the catch though: Since none of these dimensions have ever been measured, it's all just a theory. In physics, if it cannot be measured, it isn't real.

What can it even mean for a dimension to be "small"? An object can be small, but a concept?

Brian Greene's analogies all fail. All the analogies in the world ultimately fail.

What evidence leads you to believe that relativity is not sound?

In the "relativity of simultaneity" two observers come to contradictory conclusions. This is unacceptable. While observers in rel agree on if A is longer than B or if A has greater velocity than B, they disagree on the simultaneity of AB and CD. As we know there are no contradictions in reality. This indicates that time, at least as measured, is not fundamental to reality. But relativity is based on the idea that time IS fundamental.

I agree that the premise behind higher dimensions aren't necessarily correct. But to dismiss it as a whole isn't very scientific. If you can prove it, great. Or else it doesn't exist.

How will you "prove" that my table is 4, 5, or more dimensional? In which direction will you move it? Will you show that the inverse square "law" of gravity is different on tiny scales? But here you have just shown that the inverse square "law" is not a law but just a macroscopic correlation, a good heuristic formula. You'll have a new quantitative relationship for the attraction between bodies. Will you throw the table into a collider and tell me you pumped in more "energy" than you got out? What is this "energy", can you point to it? Show me a picture of it?

All of this said. You can be an fully objectivist (like me) with time being just an useful "idea" and not something HARD-REAL like matter,space and movement.

I was not trying to promote subjetivism, just pointintg the different nature of "time".

Space is not "real". Space is nothing, and there is no nothing.

I like your ideas on time and movement.

Question, just to learn.

Anything that can be 'thinnked' is an 'existent' and 'exists' ?

Any "mental something'' exists ?

Nope. The leprechaun I am visualizing in my mind doesn't exist. The keyboard I am visualizing in my mind doesn't exist.

It exists if it has shape and location. Concepts exist although they lack shape and location if they are perceptually derived from shapes with location.

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Isn't time a quantification by a standard of certain perceived changes?

/personal rant:

As a child I had a diverent idea of time travel.

It went like this, if time is changes and all change stops at absolute zero (wich I heard on some show), then for something to do less then nothing would mean it would go backward in time.

Later I found it quite ironic to hear that there is an actual theory that says that one would go back in time if one went faster then everything. :P

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