Time is NOT the 4th dimension...

TOO typical. I've read all his/her posts and every single one contains nothing more than childish ignorance. Just a one-liner rebuttal to accepted science. Therefore it's obvious the poster is just a little kid that hasn't even completed high school yet. :shrug:

At this point in age, he should be studying and asking questions and NOT trying to TELL anyone anything.

Worse yet he may be nothing more than an obnoxious little troll.

 

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This is an interesting and informative thread. I admit to being ignorant of many of the detailed experiments talked of as I tend towards a philosophic or perhaps thought exercises about the nature of things.

The three commonly used dimensions of height(y) width(x) and depth(z) have the easily seen characteristic of division. That’s is a dot divides a line, a line divides a plane and plane divides space and if logic holds true then space divides the next dimension which in counting terms would be the fourth dimension where a dot is zero dimensions, line 1 dimension, plane 2 dimension space 3 dimensions.

It is also to be noted that the use of the word dimension is only being used as a means of describing one thing in relation to a predefined starting origin.

If the observer were able step outside of the four dimensions and universe then possibly they would see a ball moving through fourth dimensional space.

For lack of a better description of what three dimensions divides a larger dimensional concept into, it might as well be called time.

However it would be silly in the extreme to think that time travel could exist. Well just imagine moving every atom in the universe back a previous position.

 

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And your point would be...?

Huh? No.

No.

Do we not already see a ball moving through four-dimensions?

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Why?

And how about localised time travel?

 

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Ickyrus, I think what you're saying is that just as 'x' can parametrize a line in space then 't' can parametrize a line in a more abstract sense. This is precisely how it is dealt with in physics. An object's motion sweeps out a line both in space and in space-time. Just as (x,y,z) form the coordinates of space then (t,x,y,z) form the coordinates of space-time.

In Newtonian physics this is somewhat unnecessary because the time component has no 'mixing' with the spatial components. In relativity this changes and it's possible to mix the time component in with the spatial ones.

Just as doing the basis rotation \(\{ \mathbf{e}_{x} \,,\, \mathbf{e}_{y} \} \to \{ \frac{1}{\sqrt{2}}(\mathbf{e}_{x}+\mathbf{e}_{y}) \,,\, \frac{1}{\sqrt{2}}(\mathbf{e}_{x}-\mathbf{e}_{y}) \} \equiv \{ \mathbf{f}_{1} \,,\, \mathbf{f}_{2} \}\) mixes x and y and gives you a new basis \(\mathbf{f}_{i}\) in Euclidean/Newtonian formulations, relativity allows you to mix in the \(\mathbf{e}_{t}\) term too. This means that it is no longer a matter of convention whether you consider time a dimension of reality, it must be included.

 

It's certainly a requirement that time be included when doing computations that involve relativity, however you don't have to be considering anything that advanced for it to be important.

When describing ANY event, past or future, it's not only necessary to locate it in the common three dimensions (x,y,z), one must also locate it in time (t) in order to tell WHEN. A common example would be the location and TIME that a planet will be at that specific location for programming a space probe. If someone were foolish enough to ignore the WHEN they will most certainly waste a multi-billion dollars worth of effort and equipment.

Another example is even more common - a doctor's appointment. You may know the location of his/her office (x,y,z) but unless you also know the 4th dimension (WHEN) you are pretty dead certain to miss the appointment.

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@Read-Only:
Yes that’s a good way of putting it.

@AlphaNumeric :
Transforms of co-ordinates and the axis used are made to simplify the math that is trying to describe observed phenomena, if time is part of the description then it has to be included. The way we measure time is by comparing the motion of one thing against another moving thing. We only know time because we can remember things being in a previous position.

The other aspect of this is that only an observer outside of our time-stream could tell if our time-stream was moving at a uniform or variable rate relative to an outside our time-stream method of measuring time.

The original poster requested avoidance of the mathematical practice of saying dimension is a parameter like colour or frequency, atomic weight etc, thus restricting the dimension argument to the commonly used dimensions.

I repeat "It is also to be noted that the use of the word dimension is only being used as a means of describing one thing in relation to a predefined starting origin." This was effectively R. Descartes purpose when inventing the Cartesian co-ordinate system. If Descartes spent his time in a circular rooms we might have found ourselves using polar co-ordinates!

Hope this clarifies any confusion.

 

A time stream outside of our own would have to be separate else all sorts of horrific causality issues arise. Hence that dimension wouldn't really be a useful frame of reference either. There's nothing wrong with us considering how time passes compared to how it passes for others, that's what relativity is all about.

If you remove the ability to formalise a description you can just make up any all nonsense.

 

How do we know E=mc^2 is true?. . . .Nagasaki? . . . Hiroshima?

 

Every nuclear power plant across the planet.

 

Therein lies one of the fundamental flaws of language.

 

Well I fully admit I didn't know shit about Einstein's papers or even understand them but holy hell the arguments put against what I actually cared to talk about were like they were from ree-ree's.

 

First it was derived. Here's one way to derive it that is similar to Einstein's derivation.
http://home.comcast.net/~peter.m.brown/sr/mass_energy_equiv.htm

The emperical facts come from nuclear physics and high-energy particle experiments. The Sun itself is just a huge nuclear reactor. But that relationship is proved every day in accelerator labs around the world.

 

Reality is not something which the concept of dimension belongs. In nature there exists space and to locate a point in space it takes a minimum of three numbers. That’s why it’s said that space is 3-dimensional.

When Einstein formulated relativity Herman Minkowski realized that it could be expressed in a more geometrical fashion if one defined a set whose elements were events where an event is defined as a particular place at a particular time. While an element of space is labeled R = (x, y, z) an element of such a set of elements is denoted as the set M consisting of all events each of which are labeled (t, x, y, z). This set consisting of all events is called spacetime and is defined and described further here - http://en.wikipedia.org/wiki/Spacetime

For more on it see http://home.comcast.net/~peter.m.brown/sr/spacetime.htm

Since it takes a minimum of four numbers to uniquely determine an element in spacetime it is said that the dimension of spacetime is four and that time is the fourth dimension of spacetime

You’re starting your arguments with incomplete ideas. That’s why you have it all wrong. No physicist has ever said that time is the forth dimension unless it was clear what it was it was the forth dimension of. And any physicist who understands relativity will say that time is the forth dimension of spacetime.

This shows that you don’t have the same understanding of time that a physicist does. So what you’re talking about when you use the term “time” is far removed from what a physicist means by it. To learn that you need to closely study the following from a well known name in relativity - http://users.wfu.edu/brehme/time.htm

A few parts of that are close while the rest is really out there. Read the above page and you’ll be on the right track so long as you understand that the link defines time as a physicist uses the term. So any claims that you make about that page will be wrong, ny definition.

 

You’ve made some good points if strictly speaking of empirical events:

For clocks the periods, frequencies, etc., they use to keep time are merely two points of a change in position. The two points are a starting and stopping increment of a motion. The motion in-between those two points becomes defined as the frequency, or period used to calculate and define a time unit. Equal time units (to the clock’s) need only be equal in ratio to its units of motion as distance/magnitude of change (magnitude is commonly defined using a “time unit” within a distance as “speed”). The ratio relationship is seen in a simple calculation such as t=x/s. The tautology of this is, empirically the time unit is a unit measurement for two points of a motion, yet speed is defined as a change in position per time. Making time and speed essentially the same thing stated different ways (they are both a unit measurement and increment of a motion).

This connects the first point in an interesting way, again when strictly looking at empirical events. Physical change is caused via motion (it may be more accurate to say via a change of position in space). As we saw clocks measure motion in increments that are its time units. Remembering to consider all the motions of macro and micro, nothing changes from a photon, to your body’s age, to the creation and expansion of the Universe, without energy (particles, matter, etc.) changing position (motion). If we defined time only as it relates to empirical events, it would clearly be a unit measurement or increment of a change of position in space. If you keep an eye to where the empirical reference to a change in duration lies, you’ll likely always be able to see it is the increment of motion(s) (micro, macro). This also appears to shows the necessity of space-time (a Euclidean distance to unit measurement of motion) in describing events; since distance is only relevant to motion (i.e. no motion any distance is infinite it is only relative to motion, or what empirically time units describe).

 

Time is simply a measure of the rate of change.
Time also is as much a dimension as is length, breadth and height.
This is because time is not absolute. There is no universal NOW.

 

not its not

time in and of its self , has no physicality to it

 

Is too. [/kindergarden]

Neither does length.

It sounds like you are confused, thinking people are saying time is a spatial dimension. That's not what they are saying/what time is.

 

how so ? how does time invoke change/movement ?

 

Can you explain what you mean by this I more detail? It seems that if you’d hold that position then you’d also hold that space in and of its self , has no physicality to it. Would that be an accurate intepretation of what you have in mind?

I can't speak for Dywyddyr but I agree with what he said. Saying that change/ movement can't happen without time. does not mean that that time causes motion or change. It means that time is the name we give to the phenomena we know as change.

Did you see the link I gave above? It explains all of this and is a physicist’s viewpoint of what time is. Robert Brehme is well known relativist. His page

http://users.wfu.edu/brehme/time.htm

is very good.

 

sure

time has no substance , no length , depth or breadth

I can't give you a piece of time , physically

space has no physicality to it

I can't give you a chunk of space