×

# The Fourth Dimension.

Me and my friends were having a discussion today on what actually is the 4th dimension. Many said that it's "time". But I don't think so. Though I don't have an answer to what is actually the 4th dimension is but 'time' is definitely not the answer. Reason 1:- We cannot measure a two dimensional quantity of a one dimensional object. e.g.:- we can't measure the breadth of a line segment also we can't measure the height of a square. But we can measure the time taken by a particle moving rectilinearly to cover a certain distance. (we are measuring a 4th dimension quantity in a one dimensional motion. This doesn't seem well!). Hence "time" is definitely not the fourth dimension. Reason 2:- Time is a relative concept. But things like length used to define dimensions are well defined. What are your view's? Please reply if you have some different view's.

Note by Pranit Bavishi
3 years, 4 months ago

MarkdownAppears as
*italics* or _italics_ italics
**bold** or __bold__ bold
- bulleted- list
• bulleted
• list
1. numbered2. list
1. numbered
2. list
Note: you must add a full line of space before and after lists for them to show up correctly
paragraph 1paragraph 2

paragraph 1

paragraph 2

[example link](https://brilliant.org)example link
> This is a quote
This is a quote
    # I indented these lines
# 4 spaces, and now they show
# up as a code block.

print "hello world"
# I indented these lines
# 4 spaces, and now they show
# up as a code block.

print "hello world"
MathAppears as
Remember to wrap math in $$...$$ or $...$ to ensure proper formatting.
2 \times 3 $$2 \times 3$$
2^{34} $$2^{34}$$
a_{i-1} $$a_{i-1}$$
\frac{2}{3} $$\frac{2}{3}$$
\sqrt{2} $$\sqrt{2}$$
\sum_{i=1}^3 $$\sum_{i=1}^3$$
\sin \theta $$\sin \theta$$
\boxed{123} $$\boxed{123}$$

Sort by:

Reason 1-Time as space are linked (Einstein's relativity). The fact that you can measure the time of a moving object is a confirmation that time is one of the dimensions. If a particle is MOVING..you are measurjng a 4D motion in a 4Dplane, not 1D. Reason 2- space IS RELATIVE...and it varies according to TIME. As you approach speed of light space contract...time dilates. This is a CONFIRMATION that this 4 components are linked together..hence Space-time (relativity). You are defining time wrong.. that's why your conclusions are misleading . Time is in theory not unidirectional. If you travel faster than speed of light time should reverse. It seems a simple misconception of "time".

- 3 years, 4 months ago

As what our physics teacher said, if you travel at the speed of light, you don't reverse time. you stop it.

- 3 years, 3 months ago

Yes, that is correct. If one was to travel FASTER than the speed of light then time should reverse. Then again, as you approach the speed of light your mass approaches infinity.

- 3 years, 3 months ago

that means time has a constant which is constantly maintained with mass

- 3 years, 2 months ago

I dont get it. Explain please?

- 3 years, 3 months ago

what makes you say time should reverse?

- 3 years, 3 months ago

If you know c or c++ language try storing values to this 4d array and find how it works int a[][][][]

- 3 years, 4 months ago

but how? Give me answer or copy of program

- 3 years, 3 months ago

You're comparing time and spatial coordinates! These two are completely different concepts. That's where the concept of spacetime comes into play. What these 4 dimensions mean is that in this universe we need these 4 parameters to determine the state of an object. You cannot define a position of an object without mentioning the time when you recorded your observations. Coz in a different time it will be elsewhere. Hence time is a fourth dimension

- 3 years, 4 months ago

I dont see how time can be a dimension, if you propose so, how would time be helpful in determining the 4th dimension of a solid cube placed on the table top

- 3 years, 3 months ago

Multi-dimensional spaces, four or five dimensions are a usual tool for describing independent variables with no correlation between themselves. When applied to physics, a fourth dimension may indeed be time, because it's independent from space dimensions, according to this definition. You, me, everything, we are nothing but a snapshot of space taken at a specific time.

- 3 years, 4 months ago

In order to have 4th dimension space you have to make 4 lines intersecting at a point ,which are mutually perpendicular to each other(i.e every line must make 90 deg. with other three lines).But this not possible in our 3D world.

- 3 years, 4 months ago

I think if we close the x, y and z axis in a very very big sphere (which is time), all axes will be almost perpendicular to that, in that case time will be fourth dimension. Every thing is moving in time. I may be wrong.

- 3 years, 4 months ago

hey .. who said that dimensionsional lines need to be at 90 degress........ there is nothing which tates dimensions must be at 90 ................ but i think...... 3 dimension will remain as it is with the addition of a unique imaginary dimension ( relative ) . I mean it will be dynamic dimension . I will change according to our point of view........................................... and this might be the greatest reason that we aren't able to detect it bcause its not fixed . we cant feel it but exist . It can be time as........... its a fundamental property of nature. and let me tell u all that......... u actually in ur daily life use time to measure distance ... what u say ... how far is new york from london ?? u dont say its 3459 miles far but u say ' its of 6-7 hrs... right ???

- 3 years, 4 months ago

this is because the time axis is imaginary and can't be realized physically.in quantum mechanics many a times, it requires to qork with infinite dimensions.theM theory for instance assumes 13 dimensions of space and time

- 3 years, 4 months ago

analogy of dimension is quite simple:- it is defined as the no. of independent factors required to locate or define a point that space. for example in our perspective of 4 dimensional space time we need 4 factors to uniquely determine a point event that is (three dimension of space and the other time ) you can easily see time or other three dimensions are independent of each other . for an instance take a point event for a cuboid, now change it's dimension of length the breadth or height is unaffected . for more information go to the link below http://en.wikipedia.org/wiki/Dimension(mathematicsand_physics) .

- 3 years, 3 months ago

Exactly. A more concrete example would be if you were going to a party in NYC. To get there, you need four pieces of information. You need to know what avenue it's on (space dimension 1), what street it's on (space dimension 2), what floor it's on (space dimension 3) and when it is (time dimension)

- 3 years, 3 months ago

Hey, Pranit, You must take a look at this . Not too complex and easy to understand

- 3 years, 4 months ago

The most awesome thing i have ever seen... (From that page you gave link of ) A tesseract undergoing simple rotation in 4D... woohoo ! So awesome !

img

- 3 years, 4 months ago

awesome

- 3 years, 4 months ago

the tessseract, thanks for the graphical gk, really awesome and have learnt something new, this has given me a concept of the 4th dimension, now if a tesseract requires the cubic prism to go withiin itself , concentrate on the words within itself and in the process come out again, and so on and so forth , then i can only think of one concept put forward by stephen hawkings and that is the supernova which makes it go within itself as it cannot sustain its own mass. then gentlemen and ladies that qualifies as the fourth dimension! and it fits the parameters of being in space before it becomes a supernova in x,y,z. axes.

- 3 years, 2 months ago

How to rotate yourself... IN FOURTH DIMENSION!

- 3 years, 3 months ago

Maybe we all are moving in the fourth dimension like the tesseract animation, rotating ourselves on an atomic/subatomic level and our brain perceives that rotation as cumulative in effect to where we interpret ourselves as "walking". If that were also happening, could we perceive that? Would that be a Schrodinger's Cat scenario?

- 3 years, 3 months ago

Is it neccerary that 4-D always move like it? Can it be stationary

- 3 years, 4 months ago

It does not show that 4D is moving... It shows rotation in 4D, means just like you rotate your pen in 3D , this is how one will rotate in 4D

- 3 years, 4 months ago

the pen will look very strange

- 3 years, 2 months ago

can u give exact what is 4-D

- 3 years, 3 months ago

a 3D object moving in space itz realy 4D

- 3 years, 3 months ago

watch interstellar

- 3 years, 1 month ago

Should we create a Facebook page for this ? So we can discuss better?

- 3 years, 4 months ago

i think you might be getting confused about what dimensions are, think of it this way imo. consider that to locate any point on a sheet of paper, i need only draw 2 axes, no less, and use that as my coordinate grid. (say, the x and y axes). if i have a volume in 3D space and i want to locate any point in it, i can use a third axis, z, say. in general for n dimensional space, i need n axes to locate a point. this way of thinking of a dimension as simply a piece of information about a point in a space allows one to get to the idea that time is a 4th dimension. not in the spatial sense, but in some sense you can see that time is also required to describe an event fully. say if you had a party, you'd need to know where in space to go to the party and when it is as well.

- 3 years, 4 months ago

Pardon me if i am wrong but , in that way velocity could also be taken as the 4th dimension , as you cant describe time without reference to how fast is it being measured

- 3 years, 3 months ago

we probably will never figure out what the 4th dimension truly is

- 3 years, 2 months ago

I don't understand what you're trying to say here, knowledge of velocity isn't a necessary piece of information to be able to come to the party I was talking about earlier. also measurements can be treated to be instantaneous so theres no need to complicate matters with how fast you're measuring something

- 3 years, 3 months ago

The fourth dimension is like a video recorder, capturing at an infinite number of frames per second. The ZhiJie Goh which started this note has ceased to exist. Every moment now, we are changing. We are a different person.

- 3 years, 4 months ago

Rotation in four-dimensional space

https://youtu.be/R1rzI0Y_d3I The 5-cell is an analog of the tetrahedron.

https://youtu.be/BjvdrhK8yws Tesseract is a four-dimensional hypercube - an analog of a cube.

https://youtu.be/Pa0c7M4lZv0 The 16-cell is an analog of the octahedron.

https://youtu.be/np0ZxC1wXqc The 24-cell is one of the regular polytope.

https://youtu.be/T01qw0_qitI A hypersphere is a hypersurface in an n-dimensional Euclidean space formed by points equidistant from a given point, called the center of the sphere.

- 3 months, 2 weeks ago

Time is a dimension. We measure the world relative to time.

The human mind does not see the world in a way that is "true". It sees the world in a way that is "useful".

Time travel is possible in the forward direction. There is no evidence that going back in time is possible. I like to believe that it works on the same principle as entropy, that it is easier to go in one direction than the other, though not necessarily impossible.

Age is the total amount of time difference experienced by one's body.

- 3 years, 2 months ago

You are right.Time is surely not a dimension but one of direction among those four , from which 4th dimension is made of. Another one reason for time being a direction is that Space and time are linked.Space changes its properties according to time. Juliano Morimoto is right .

- 3 years, 3 months ago

Imagine a stationary object..it doesn't travel any distance..so only thing u can measure is... How long has it been there.. So time is one of the dimensions.

- 3 years, 3 months ago

I feel time is the ordered sequence of events in a higher dimension where each event, each moment has its own unique identity.

- 3 years, 4 months ago

constant motion we dont always see constant motion but it seems reasonable but the tesseeract though is just an attempt at putting a 4d plane in 3dish "graphics" who knows what 4d is like just like we can control an object in 3d and modify imagine the access we have if we knew what the 4th plane has to offer especially quick travel through space. btw time can be measured in one dimension but ironically we are measuring that one dimensional motion in 3 dimension aka this world. who knows what the 4d plane is i dont want the knowledge to get in the wrong hands it might be destructive or constructive. i honestly dont know what this 4th dimension could be, just thinking about it makes me wonder in awe. i think its this analyze from my idea nextby, i think the 4th dimension is like a string with a rocket floating on it you shorten the string you shorten the rockets path to the next end point from this i say that the fourth dimension is the stability and instabilty of the other three dimensions(solid,liquid,gas,plasma,Bose.Einstein condensate) the 4th dimension is space and its manipulation in these "crappy" three dimensions we can only go through space . the 4th dimension is what this universe is truly made out of (dark matter and energy) the unknown stuff that is the fluff or filler in this universe to actually find the dark stuff we need an understanding of the 4th dimension. The 4th dimension is the hidden dimension the one made of dark stuff(energy & matter) but i think with manipulating the dark stuff you can manipulate distances without the dark stuff the universe if probably like a balloon without air. if only i could take a vacation to another planet by shortening the string i was talking about the 4th dimensional string.

- 3 years, 4 months ago

ignore the constructive after destructive engligh was never my best subject anyway

- 3 years, 4 months ago

greatest idea of all but i forgot to put it, the fourth dimension is also the dimension where infinity is now actually verifiable,witnessable,

- 3 years, 4 months ago

i m still not very well versed with eisteins relativity concepts.....after all all we percieve see is the project of reality on the three dimensional space......we may add more and more dimensions in our mathematical model to explain reality.....but by the endof the day all we have in our hands is the three dimensional projection of reality .....according to my opinion and the little shallow understanding gained by me is that it could prove much better understanding of reality only if ......." we considered the entity called "time" as some very unique and subtle(difficult to percieve) form of energy.......here by the word "subtle" i mean it is some entity that has existence is a realm unaccessible to us but we are definitely exposed to certain effects and nature of time.... its subtleness just reminds us of the subtleness of the software part of the computer system.....we cant describe software programs as some objects that we can touch, feel and see or some object that we can describe in terms of particles(the usual darling trend followed in modern science- somehow we force ourself to get some particle to explain certain undetectable entity or even phenomenon......similarly time is an entity that can never be explained in terms of favourite trend followed in science that is to get some particle.....the reason why i m stress on this irrelevant connection and also a possibility of "the particles" is that the moment u use the word "energy" it is very tempting to start searching for some particles....so to avoid that possiblity i m condemning this "particle notion".....time according to my opinion is some subtle energy that has just one job - to kill events to allow new events to appear which are in turn killed by the newer upcoming events(very simple and lucid and might be incomplete description)....to keep discuusion simple let us consider a particle observed from some inertial frame of ref. moving with some nonrelativistic speed ....the particle is at some instant tA at a point A.......after the passage of some time it is at some point B at some instant tB....even if the particle is at rest we find the particle at the same point but the time coordinate is changed from tA to tB......suppose we have everything :the required temperature , the required pressusre and required concentration of chemical and even the required catalyst ready with us........but suppose this entity "time" stops killing events no matter what arrangements we make.....it is impossible for the reaction to occur.... infact nothing would work if this energy "time" did not exist or stopped its functioning....this shows to some extent that time is an energy...... friends please comment on this veiw of mine.....waiting for a reply

- 3 years, 4 months ago

M not sure whether time is the fourth dimension or not . what I think is , if we imagine a cube or any 3d object , its length breadth and height gives us a fair picture of 3 dimensions , any change in any of the 3 measurement can be taken care by using x y and z axises . apart from these any change in cube can only be its position as a whole . a unit measuring that change in position will be the fourth dimension . perhaps our whole world is a 3d system which is.moving in a direction and the 4th dimension measures that movement . perhaps evolution happens because world is moving , what if its not the meteors that strikes dinosaurs and it was the whole system moving towards meteors .. The fourth dimension measures the relative motion between two 3d systems

- 3 years, 4 months ago

Perhaps I might be wrong But IT have a different understanding of the 4th dimension We can observe from previous dimesions that each one of them is a collection of the previous one Collection of many 1d objects gives a 2d object But as far as collection of 3d objects is concerned it can as well be defined in itself only But suppose something was able to exist at different places at once Like its head at one place its body in other this way it woukd be intangible to other 3d objects. So this is my theory please correct me if you feel otherwise

- 3 years, 4 months ago

Time is not a space dimension! It's a total different thing. When we work with relativistic problems, we take the three space dimensions as a whole and time as an another dimension. Do not consider it as a "space" dimension. Time is something which only has one direction. i.e forward unlike space dimensions. Had time been similar to space dimension , we could not only travel into past but future as well. I will recommend the book "what is relativity" by Jeffrey Bennett for time and spacetime understanding.

- 3 years, 4 months ago

1.| Length is not well defined even Euclid in his elements could not give the correct definition of length. 2.| Length like time is also relative it changes as speed approaches that of light. But I am also in agreement with Pranit in some aspects as time does not have any physical significance for us.

- 3 years, 4 months ago

Think of a 3d shape going through a plane. One the plane it would appear that the slice is changing shape but in an extra dimension it is a higher dimensional object moving through. This is what 4D as time really means. We can only see the 3D intersection of the 4D universe which has time forward and backward.

- 3 years, 4 months ago

watch this video

- 3 years, 4 months ago

Take a look at this. I can't really explain it in words, but this might help you ^__^

- 3 years, 4 months ago

Great video.....

- 3 years, 4 months ago

Time is the fourth dimension. Actually, we are only measuring the fourth dimension using one dimensional motions and not 4 dimensions using one dimensional motion. Height is a single dimension. An object can have height without having any length or breadth, like (0,0,z). Also, time is relative, but so is length. For example, consider 1m. It is the distance traveled by light in vacuum in 1/(299,792,458)th of a second. So, we are defining length relative to time. In fact, the faster you go, the smaller you are. Fast, by itself, is based only on time. So, your friends are quite correct in saying time is the 4th dimension. (4th dimension is actually SPACETIME)

- 3 years, 4 months ago

In 1D, we define a length.

In 2D, we define an area.

In 3D, we define a volume.

So what should be defined in 4D?

Whatever it is, does its unit make sense? ( $$sec . m^3$$)

I think it should be $$m^4$$, like previous units, which implies that the fourth dimension is a length but in a new unfamiliar direction.

- 3 years, 4 months ago

If what you said is true then should unit of time be $$m^{4}$$

- 3 years, 4 months ago

(And it is impossible that unit of time be $$m^4$$ hence time can't be the fourth dimension.

- 3 years, 4 months ago

1m=distance traveled by an particle in 1/(299,792,458)th sec . now meter is dimension but it is not necessary that dimension should be m^4 dimension is something by which you can state the position or situation of object as i have given it in above equation , meter is also represented by the distance traveled in given time therefore time is the fourth dimension

- 3 years, 3 months ago

We are living in a three-dimensional universe, so it is hard to imagine or think about what would be the fourth dimension.

But after reading your article, the idea of "Seeing Through Objects" crossed by mind..

We can not see through objects, this supports the idea that "the $$n^{th}$$ dimension can't be seen or used in a $$(n-1)^{th}$$ dimensional world.

We can measure the fourth dimension in 1D, 2D , or 3D , maybe by claiming that a certain object has or has no "tendency or capability to make others see through it". (I hope this is clear, or say that we cannot measure or understand the fourth dimension as long as we are in a third dimensioanl universe).

I hope this makes sense, be free to criticize any point.

- 3 years, 4 months ago

Like a 2D plane can be bent in the 3D direction to make 2 points touch each other, is it possible that a 3D space be bent in the 4D direction to enable us to teleport?

- 3 years, 4 months ago

This is exactly how wormholes work. (I strongly believe they exist)

- 3 years, 4 months ago

So do i

- 3 years, 4 months ago

Well.. This may be true, but we can't tell or assure this since we live in a three dimensional universe.

A similar Idea is the following" If we are living in a fourth dimensional world, then we can extract the egg yolk from an egg without crashing the egg shell".

- 3 years, 4 months ago

The question is how? N I expect u to answer it Hasan

- 3 years, 4 months ago

If you meant "how" about teleporting, then your question has no answer , because we can't do things specified for a higher dimension than the third one(where we live).

Teleporting idea arose in many researches that are related to physics( mainly optics), where they talk about exceeding speed of light and similar stuff..

- 3 years, 4 months ago

Which is nothing but time travelling. Am I right ??

- 3 years, 4 months ago

Yes its time travelling(when you become faster than light), not to be confused with teleporting in four dimensions, which is not time travelling.

- 3 years, 4 months ago

How about the red bull guy that jumped of the space?

- 3 years, 3 months ago

really I haven't heard of that yet... It may be a legend... can you tell me where I can read about it?

- 3 years, 3 months ago

Nopes, teleporting is instantaneous change of position in the 3D world, like going from earth to moon in a fraction of second, like ... ZOOOOOOOP ! Disappear from one place and appear at the other. Time travelling is different thing.

- 3 years, 4 months ago

Then what is time travelling ?!!

- 3 years, 4 months ago

Time travelling is going to a different time, just like they showed in the movie "Harry Potter-Prisoner of Azkabaan" , that is travelling along the time-line (like number line) dimension, in a forward or backward direction.

- 3 years, 4 months ago

Backward time travel is not possible

- 3 years, 3 months ago

Well we say that because... see, in 3D you have things for travelling, like a rocket, car bus, legs etc. Like that, we don't right now have a device/object/thing for travelling along the dimension of "time" (dimension here means one of the fundamental 7 said in Physics)

- 3 years, 3 months ago

Oh yes ... I felt confused with the names...

- 3 years, 4 months ago

Got it. Thanks...

- 3 years, 4 months ago

szia

- 3 years, 4 months ago

I AGREE WITH YOU

- 3 years ago

Time is certainly a dimension.When you say that we can measure time of a particle moving rectilinearly, it is actually not time.It is the concept that we have applied .It is the flow of time,which is a single coordinate which is considered to be fixed on earth.For example,The coordinate of a point on the x-axis can be written as(x,0,0).We have taken this rate of flow of time on earth as our reference frame.But the flow of time gets slow near a strong gravitational field.Like,near a black hole space-time gets curved due to the high gravitation of the black hole ie. flow of time slows down.If you saw "Interstellar",then remember for the planet near the black hole,one hour stands for 7 earth years.So,for earth one sec equals one sec.This is a single coordinate in the time dimension.But there are places near much stronger gravitation fields where where one earth sec is .00000001 second.This is another coordinate.So,when we say that some event occured for 5 seconds,it is actually not time.It is the concept created by us for helping us in complex problems. There is an interesting example.The satellites orbting the earth experience less gravitation pull than we do on earth.Thus time on earth flows extremely minutely slowly than on those satellites.For this reason the satellites have to right their clocks by one second every 35-40 years.So you may say that they are on a fractionally different coordinate of time dimension than us. If you could or could not understand please reply.Thanks

- 3 years, 1 month ago

are we talking about math dimensions or universe theory dimensions, in math there's an infinite amount of dimensions in a object but with universe theory there is like 10 to 11 depending on what you believe time being the disputed dimension.

- 3 years, 1 month ago

the most awkward thing i feel about time and its study is that .what we are observing just now and trying to make the perception of it with respect to time is further the function of time. i logically don't understand how can we have anything independent or exclucing time

- 3 years, 2 months ago

I myself thinks alike that time is a 4th dimension. As good as a super scientist, I also don't have any reason to explain this. And one more point, as Einstein said that time may be a continuum woven perfectly with space. UGHHHH I JUST DON'T KNOW.....:(

- 3 years, 2 months ago

Has it ever occured to you that space and time are two entirely different dimensions just happened to be tangled in points. Like how human mind can analyse space dimensions, maybe a more intelectual brain can analyse time in different dimensions where humans are limited to understanding only 1 dimension of time.

- 3 years, 2 months ago

this is the answer to the above question its not time 1st 2nd and 3rd dimensions occupy a continuous state space meaning a square is built on another square a cube on another cube but in 4th dimension each 4th powers and higher is an independent entity much like how the suns of the universe are look at my solution https://brilliant.org/discussions/thread/solution-to-why-we-cant-see-4dimensionsand-higher/?ref_id=453528

- 3 years, 2 months ago

First we need to change our mind set about the dimension ..our mind deals each thing like coordinate geometry ..x y z hmm But we have made some things that really do not exist...... Like. Squar' circal 'line and other 2d... And saying that time is not a dimension is not right... Understand it like ..... You r watching a slow motion movie and a ball is thrown from the ground and when ball fly in space it makes its so many copies and our mind cannot notice that pictures and makes them signal.. At each second the ball has infinitely copies..and each second represents a different location an structure of balll.....

- 3 years, 3 months ago

its quite easy to understand that time is 4th dimension.

actually the surrounding which we see around have more than 4 dimensions but it depends on the observer how he perceives the object.

Ex - A electric wire passing far from us looks like a line or 1 dimensional from far distance but... for an ant or insect crawling on it , it is like a cylinder i.e 3 dimensional .

and as time is relative( i.e. it depends on mass and velocity for the rate of time to pass) similarily length is also relative (i.e. depends on velocity)

- 3 years, 3 months ago

Hello! Time can be treated as a whole new dimension, but it has no equal footing with the dimension of position (e.g. rectilinear coordinates). There can be a fourth dimension, there can be infinite dimensions! But THE fourth dimension is arbitrary, and can be treated as what is mathematically plausible (e.g. transforming to another vector space). The thing is that, most of the time we set functions (velocity, for example) to have time as a variable, therefore confusing it being a position dimension (or, as I'm afraid, a vector). So, there you have it. Not just 4 dimensions but infinitely many dimensions, with time as just a 'dictator' of the object's state.

- 3 years, 3 months ago

Rate of change

- 3 years, 3 months ago

time and space are relative and einstein's theory has been proved, also the concept of length also changes with rounding corners.

- 3 years, 3 months ago

Physics says that a body can never be at absolute rest It is of because, if a body is still existing,then it means that it is going in the direction of time

- 3 years, 3 months ago

Time is a forth dimension but it is not the fourth dimension. Just as we can say the 1st is height, 2nd is depth, 3rd is width, we can also say that the 3rd is the height, 1st is the depth, and the 2nd is the width.

- 3 years, 3 months ago

fourth*

- 3 years, 3 months ago

how do you define dimension and time?

- 3 years, 3 months ago

Even length is relative from one person to other ...

- 3 years, 3 months ago

Note that a cube within a cube is the proyection or shade of the 4th dimension on 3d.

- 3 years, 3 months ago

It does not needs to be time, a function y= c is a one d function, f(x) is a 2 d function, f(x,y) is a 3 d funtion and so on. Yes time can act as a dimention as it happens in a wave equation y= sin( kx - wt), this is a 3 d equation.

- 3 years, 3 months ago

In some respects it can be, but in others in can't. I'd say it is, given that (as special relativity has shown) space and time are relative and practically interchangeable in many situations, so time deserves just as much recognition as space. Also, you can mathematically define it as a dimension. However, an argument against this would be almost purely philosophical, and that just gets annoying.

- 3 years, 3 months ago

yes I am agree with @Juliano Morimoto . Any moving particle have all the 4 dimensions whether it is following linear path or rectangular path. And of course space is the function of time.

- 3 years, 4 months ago

after the space, there is nothing more then to measure . so it's time ! ! :D

- 3 years, 4 months ago

4 dimension implies moving through space-time.......the continuum which can be put to use to describe an objects postion before and after some time!!!!!!!

- 3 years, 4 months ago

Here are my objections to your reasons. Reason1, is simply a trapping of language. What if there's an object that exists in 4th dimension, and we are measuring motion, time, length breadth and thinking that is the object? Reason2, Relative to what? I can argue that length is defined relative to the standard objects at IUPAC.

- 3 years, 4 months ago

A change in position spends dimension. The position itself is in universal scale having coordinates. lets say you have a point living in zero dimension which finds a way out to other dimension creating the first dimension, the point didnt know that it is in the first dimension. To go to 1d you need 2 zero d. So to go 4d we need 2 3d. And we call it TIME. just my idea.

- 3 years, 4 months ago

dimension is not just defining a space,if we say about a fourth dimension ,it says about the object..i mean both the location in terms of space and even in terms of time...eg;if we need the distance from delhi to hyderabad we can say it in both distance and even in time so time can be a 4rth dimension.....i may be wrong!...i donno exactly

- 3 years, 4 months ago

Space-time is the basis of all the theories of multiverse. Dimensions are of 2 types: space dimensions and time dimensions. Combination of them defines the dimension of a particular universe. Eg: Our universe exists in 3+1 dimension. That means our universe has 3 space dimensions (Length, Breadth and Height) and 1 time dimension. As for the 4th dimension, if you are talking in context to space then it means the extension of diagonals of an object (You can search for the proper explanation as I cannot do that in written). In context to time, I do not know :P :)

- 3 years, 4 months ago

Reason 1: Your reasoning is wrong here because without a time dimension there is no concept of a 'travelling' particle. You would only know that the particle is traveling when you observe its position with time. So even if it travels in a one dimensional space, the fact that its traveling makes it a two dimensional 'spacetime'. Reason 2: Well, length is also a relative concept according to Einstein's special relativity.

- 3 years, 4 months ago

A 4-D being would be a god to us. It would see everything in our world. It could even look inside your stomach and remove your breakfast without cutting through your skin, just like you could remove a dot inside a circle by moving it up into the third dimension, perpendicular to the circle, without breaking the circle.

- 3 years, 4 months ago

A 4-D being would be a god to us. It would see everything in our world. It could even look inside your stomach and remove your breakfast without cutting through your skin, just like you could remove a dot inside a circle by moving it up into the third dimension, perpendicular to the circle, without breaking the circle.

- 3 years, 4 months ago

As you are saying that the motion is 1d it is not completely true because it is the generalised form of 4d motion where 2 other dimensions do not change through out the motion.

- 3 years, 4 months ago

We can have breadth of a line segment which makes it 2D. If we add height to this we get a cuboid which makes our setup 3D. Now this is a static universe. Now if we add time dimension which is independent of other 3 dimensions, we now have 4D universe. I hope i have cleared your doubt.

- 3 years, 4 months ago

Do you mean that we are living in a four dimensional universe?

- 3 years, 4 months ago

Yes 3 dimensions in space and 1 in time

- 3 years, 4 months ago

Okay then... Is a sphere a three or four dimensional object?

The answer is four as you claim that we live in a four dimensional world..

- 3 years, 4 months ago

Yes, everything is 4 dimensional the sphere can be expressed in terms of 3 dimensional space and 4th dimesion of time. Foyrth dimension of time is hard to visualize as it cant be "seen" but "felt"

- 3 years, 4 months ago

You are defining in terms of 3d space and fourth dimension of time, so what is the fourth dimension of space?

Your words tell that time is a different typed dimension than space dimensions..

- 3 years, 4 months ago

Yes u r right. Time is different than space dimensions nonetheless its a dimension. The above post posts arguments which makes us feel time cant be taken as a dimension. But the arguments are flawed. Firstly line segment CAN be veiwed in a 2 D environment the second dimension ie breadth having value of zero units. The same way 4D values can be set for line or square or cube or sphere time being something like todays date and time. The second argument is also flawed as it states that time is relative which is untrue. Time is the same for me u and everybody. One cannot live yesterday or tommorrow.we live in present and time is also fixed for all. Now regarding we being able to measure 4 dimensions independently if we see we actually can. Say three axes (x,y,z) and now time (t) so total dimensions will be (x,y,y,t) to completely define an object in this universe.

- 3 years, 4 months ago

Tell me are the dimensions dependant on each other? for example, does the width of a table depend on its hight? The answer is no since we can build a table of same width but different hight.. Then dimensions are independant of each other.

Now lets suppose that time is the fourth dimension. If we had a sun that has an orbit of different length and width, then it will rotate around the earth in less time and thus time (years and days) will change. This implies that one dimension (time) of this four dimensional universe depends on other dimensions.

I think this concluded as that time can not be a dimension.

- 3 years, 4 months ago

Consider this universe of earth rotating in less Time, if having a cup of cofee you would take less time then time should not be considered as a dimension. If u feel u would take same time it should. Ultimately time is felt. U only know the answer.

- 3 years, 4 months ago

And this can't be known unless earth rotates in less time, so we can't assure or predict what is actually the fourth dimension.

- 3 years, 4 months ago

So in present universe we can assert that time is thw fourth dimension. We can have hypothetical universe in which the space dimensions also are related to each other.

- 3 years, 4 months ago

One more addition that you might want to do in the reasons, We can travel along the 3 Dimensions, like going to another point in the space. But time is unidirectional, you can't go beyond what is going on.

In the 3D , you can go and come back along any of the dimensions.

- 3 years, 4 months ago

But according to @Juliano Morimoto once u attain speed of light time reverses

- 3 years, 4 months ago

If we COULD travel faster than lught..then yes..time would reverse. Gravity..which is the bend of the SPACE affects time. A black hole is a singularity because the laws of physics break down. Time STOPS AND SPACE makes no sense at the center of a black hole, which shows you that our universe has AT LEAST 4 dimensions. If you consider string theory though..it has 11D.

- 3 years, 4 months ago

According to me, if you are not talking about black holes and ONLY talking about travelling with speed of light affects time (reversing), then it's No, time will not reverse. Because the relative motion of light will be away from us, we'll just FEEL like things are going back, means FEEL like time is going back. But if you look towards the direction in which you are travelling with speed of light, then you'll find things going on with double speed than normal. Isn't that logical ? Direction will also matter in that case, what has time got to do with your speed, go by any speed you want, but you will have relative motion that will make you feel time is running back, but it actually independent.

Also if you talk about dimensions, then we have 7 fundamental quantities in physics and their analysis is also called "Dimensional Analysis" , they're dimensions in their own way. See if you get what i mean, a good discussion going on btw ! Maybe I can learn a lot from You Juliano, please , I'm eager about your thoughts .... @Pranit Bavishi @Juliano Morimoto

- 3 years, 4 months ago

Great stuff @Aditya Raut . Though..i am not quite sure if you agree or disagree that time is the 4th dimension. Indeed you are right when you say that if we look at Light itself..then we will feel nothin..becuase light will alwys travel at a constant speed even if WE are moving at the speed o light. But the faster you move..TIME itself slows down. Of you talk about speed and direction..speed Implies TIME. Also..direction is relative to your motion. The thinghere is that time is not simply a measurement...it is a property of the universe itself and cannot be considered independent of space.

Very nice discussion indeed. But let me know what side of it you are aditya. And i am sure i will learn a lot too. Explai me etter in case i misunderstood you @

- 3 years, 4 months ago

I see that the point where we differ is "Is time independent of our motion, or time is related to space (not independent", but if we consider that time is a relative concept, not absolute, then your point seems perfect. I think we can ask some even more knowledgeable person, some senior/teacher ...

- 3 years, 4 months ago

- 3 years, 4 months ago

No, I disagree. Coz length breadth n height r dimensions of space but time..... well it is different but its our perception isn't it? I know I'm talking in riddles but your question was a riddle too

- 3 years, 4 months ago

4D means spacetime we can assume it by an example ; a cube should be taken as 3d object if the cube shown is splitted into two (not in half) we will get a dimension between same plane the distance between them cannot be seen in 3D that is the fourth dimension where time is stoped as assumed . and also described as the method of teleportation I want to present it with a diagram but the no facility posting diagrams on it.

- 3 years, 4 months ago

We can se it in this way 1. Group of infinite points us a line (1D) 2. Group of infinite line is a plane 2D and group of infinite plane is a 3D plane So 4D is a group of infinite 3D plane and to do this we assume that time provide s this new plane in which all individual exist in a plane that is at certain angle to the plane you are in .

You can think 4D plane as a bread loaf in which your time plane is different from one which is moving relative to you i.e you cut that loaf at different angle than that of mine.

- 3 years, 1 month ago

I like to imagine that, if we were able to see an object in 4D, we would see it from all possible angles, that is, the entirety of its surface, at the same time. I don't have any scientific reasoning for this, but maybe someone would.

- 3 years, 3 months ago

I think we can't differentiate space and time they both exist simultaneously both are faces of same coin.whatever u want to do whether u want to draw a line,square,cuboid u always need space and time simultaneously.

- 3 years, 3 months ago

The imaginary thread known as space -time curvature which determines the space-time distortion is the 4th dimension

- 3 years, 3 months ago

We have three spatial dimensions (length, breadth and height) and one temporal dimension (time) in our universe currently known to man. Now some theoretical physicists say that there at more than three spatial dimensions but they are minisculed. The big bang only released the aforementioned 3+1 dimensions but there are other dimensions. But one can only surmise.

- 3 years, 3 months ago

i think it should not be time . As in 3-D we measure all three dimensions in length so 4th dimension should be a unit of length. It may be that we have 4- D around but we r not understand it.

- 3 years, 4 months ago

It is a length too. We are not accustomed to see it as a length

- 3 years, 4 months ago

Time is a dimension, but there is no such thing as a "fourth" dimension. What order we put the dimensions in is arbitrary. Like, we could start with width as dimension one, then length, then height, or length width height... It doesn't matter. However, time acts differently than other spatial dimensions, so it wouldn't make much sense to call it the fourth dimension. It is the first time dimension, not the fourth space dimension. So yes, it is another dimension, but it is not chronologically the fourth.

- 3 years, 4 months ago

Cole , i think one has to really think out of the box, and the 4th dimension could exist when a particle goes out of the x,y,z spaciality and the only way that can happen is when a star collapses within itself ie when it tries to become a black hole, when that event occurs then the particle has technically taken itself out of the x,y,z spaciality and it gets into the 4th dimension of -x, -y and -z. Could this be the 4th dimension??

- 3 years, 3 months ago

What is momentum?

- 3 years, 4 months ago

https://www.expii.com/what-is-momentum/

- 3 years, 3 months ago

We cannot define units. For e.g. if you were to define 1m without defining 1cm , 1Km etc., how would you do ? How do we come to know that 1cm is this much or that much relative to something????

- 3 years, 4 months ago

The fourth dimension exiest between the two intergalactic gaps there are only a few things known about fourth dimension. Time according to me can be a factor of fouth dimension as the black holes and wormholes are considered to be ibn fourth dimension.

Reply must if you like it!!!!

- 3 years, 4 months ago

exactly have proved it mathematically check it out https://brilliant.org/discussions/thread/solution-to-why-we-cant-see-4dimensionsand-higher/?ref_id=453528

- 3 years, 2 months ago

- 3 years, 3 months ago

What is the second dimension? What is the sound of one hand clapping? There is not a clear ordinance of dimensions.

- 3 years, 4 months ago

$s^2 = x^2 + y^2 + z^2 - (ct)^2$

- 3 years, 4 months ago

according to me there are 3 spatial dimensions (length, breadth and height) and one temporal dimension - time in our current universe there cannot be a 4th spatial dimension (except for in some theories like string theory in which space can have up to 19 dimensions, but they have no proofs)

- 3 years, 3 months ago