Talk:Dimension
Number of parameters
What is the "number of parameters or measurements" needed to describe an object? Since when do angles used to describe orientation count as "dimensions"? I have reverted the introduction. Brian Jason Drake 06:34, 20 November 2005 (UTC)
- See "Electron spin" above. The spin is a parameter/measurement, but it is not a dimension. [signature added just after submitting comment Brian Jason Drake 06:44, 20 November 2005 (UTC)]
Euclidean vs spherical geometry
I had to reword the last couple of sentences of this paragraph, since east-west and north-south movements are only applicable to spherical geometry, and spatial dimensions are based on Euclidean geometry. NickBush24 06:49, 5 October 2005 (UTC)
Infinity?
I'm moving this paragraph to talk, because as far as I can tell it's either hogwash, or at least not properly sourced:
- Infinity is the 5th dimension because it cannot be defined using the other four dimensions. We know of it's existence because no matter how large you can always add one more unit of measurement to almost any distance/time/number. However since we can engineer everything from the wheel to a moon-landing using just the first four dimensions there been no practical need to recognize infinity as being the 5th dimension, although it will be necessary in describing the Theory of everything.
--Delirium 17:53, 17 October 2005 (UTC)
- The pages "infinity" and "theory of everything" don't appear to support that paragraph. Brian Jason Drake 07:07, 22 October 2005 (UTC)
- The fifth dimension is not infinity; see Hilbert space. Fredil Yupigo 00:26, 26 October 2006 (UTC)
Physics
Movement
"We can move up-or-down, north-or-south, or east-or-west, and movement in any other direction can be expressed in terms of just these three."
Can you really speak of movement in terms of just the three spatial dimensions? Doesn't the very concept of movement depend on the time dimension? Without time all you have is position and no movement. Right?
- Movement is change of location. One moment a thing is here, and another it's there. Moving is not necessarily related with time. --Inyuki 12:09, 2 Dec 2004 (UTC)
- How would a change of location occur except through or in time? Hyacinth 00:15, 3 Dec 2004 (UTC)
- You can argue that time is the same as the three spatial dimensions, so "location" includes all 4 dimensions as well as any others that may exist, and movement is still defined as "change of location", so there is nothing special about time when it comes to movement. Brian Jason Drake 06:38, 20 November 2005 (UTC)
- It doesn't matter how movement is discribed. Time has no relevence to where an object is. Therefore time is not another dimention. If time was another dimention, it would not speed up or slow down as it states in Einstein's theory of relitivity.
Spacetime
What's the difference between space and time? Haven't we treated them as one thing ("spacetime") since Einstein? Brianjd | Why restrict HTML? | 02:26, 2 October 2005 (UTC)
- In most usages, no we haven't: people continue to perceive them as 3-space and 1-time. And if you want to be picky the strong people like 11-d (10-d?) space anyway. The "physical" section seems to handle this OK; the intro is a bit odd, though it says "a space" not "space". William M. Connolley 09:31, 2 October 2005 (UTC).
- It says "a space", which is correct. In mathematics we can have 3 dimensions or 4 dimensions - they can't be the same space, so there is more than one space, and in the intro we are not referring to any particular space. Brian Jason Drake 08:36, 17 November 2005 (UTC)
Space origin
Why (how come?) our space have three dimensions of space and one of time? How did the space originate? --Inyuki 12:09, 2 Dec 2004 (UTC)
Many Some scientists believe that space originated from particales slaming together at hype-speed, thus, creating the Big Bang, but there is also an unknown factor, where did the the particals come from, and what made them accelerate so fast, so it might point to a God, or a great force, existing before and possibly after the Big Bang.:No,1 kg corresponds to 25,000,000,000 kWh of energy,the "Fight" between matter and anti-matter is simular to the rebellion against Heavean strangely,here :No,1 kg corresponds to 25,000,000,000 kWh of energy, here, http://livefromcern.web.cern.ch/livefromcern/antimatter/academy/AM-travel01.html--Dansanman 06:37, 3 February 2006 (UTC)}
Electron spin
Electrons can move in 3 dimensions in space, move through time, can spin, and don't appear to have an internal structure. How can all this be accomplished if there are only 4 dimensions? Brianjd | Why restrict HTML? | 12:00, 2005 May 8 (UTC)
- An electron's position in spacetime can be described with four coordinates. An electron's _state_ takes more degrees of freedom. It's spacetime that has four dimensions. State of a system that evolves over time is often expressed in terms of Hilbert spaces with an infinite number of degrees of freedom. Different things being talked about.--Christopher Thomas 21:32, 20 Jun 2005 (UTC)
- Physics is confusing... Brianjd | Why restrict HTML? | 08:40, 2005 Jun 21 (UTC)
Multiple Dimensions
Can't multiple dimensions exist in a way that allows a particle to be in two places at once. If so, our whole universe could be a single particle (entity) that can be veiwed from an astronomical number of locations.
Reality
"Classical physics theories describe three physical dimensions: from a particular point in space, the basic directions in which we can move are up/down, left/right, and forward/backward."
Is there anything in physics to justify the "up/down", "left/right" and "forward/backward" labels or are these arbitary directions that humans have decided to label and consider special? Brian Jason Drake 08:08, 20 November 2005 (UTC)
Science fiction
"Also, in science fiction, a "dimension" can also refer to a separate world or plane of existence, though this meaning is not discussed in this article.)"
- What article would this concept be addressed in? parallel universe? i am sure several articles aim here for that concept. - Omegatron 02:44, Apr 25, 2005 (UTC)
- It is discussed in "parallel universe", which is under a proposal to merge into Multiverse. Brian Jason Drake 08:43, 17 November 2005 (UTC)
- This proposal seems to be gone from both articles and Talk:Multiverse. Brian Jason Drake 08:05, 20 November 2005 (UTC)
String theory?
String theory certainly should be somewhere other than the science fiction section, for it has been proposed as a real theory, but it might belong in science fiction as well. Brianjd | Why restrict HTML? | 06:16, 4 September 2005 (UTC)
- I am thinking of this edit, where someone seems to have assumed that string theory does not appear in science fiction. Brian Jason Drake 08:54, 17 November 2005 (UTC)
Lead
Well I have rewritten the lead and my change has been reverted. I think however the lead should not make a too strong distinction between common sense, mathematics and physics. The mathematical definition is simply an extension (abstraction) of the common sense concept. The difference with physics is not really true. Adding a unit to a dimension is not really something that important. Not only physicist are using multi dimensional spaces with units. Economists, chemists, physicians, etc... Moreover an simple example should belong to the lead just as in manifold or in eigenvalue. This is also recommended in the mathematics project. Vb12:25, 21 November 2005 (UTC)
- I prefer your version to the one with bullet points, which reads more like a disambiguation page. Charles Matthews 12:47, 21 November 2005 (UTC)
- I prefer the bulletted version (otherwise I would have modified it after seeing the change myself). The point of an introduction is to be introductory. As long as all interpretations of "dimension" are mentioned, and have sections discussing them, I think that smaller is better. --Christopher Thomas 20:43, 21 November 2005 (UTC)
- Bulletted sections are systematically criticized as list-like when it comes to featured article candidates. List-like paragraph are frown upon in wikipedia. Prose should always be the first choice. Introductory means often understandable for the layman. From this point of view, introduction to math articles usually have to show a simple example. Opposing the common usage to mathematics or physics usage is in this case a bad idea because the mathematics concept is clearly a generalization or abstraction of the common usage. I think the present version of the lead does not present an interpretation. If you believe so, then could you expand a bit your criticism so that we can find a compromise. Vb 08:35, 22 November 2005 (UTC)
- I prefer the bulletted version (otherwise I would have modified it after seeing the change myself). The point of an introduction is to be introductory. As long as all interpretations of "dimension" are mentioned, and have sections discussing them, I think that smaller is better. --Christopher Thomas 20:43, 21 November 2005 (UTC)
- If you feel strongly that it should be prose, fine - make it half the length, and briefly touch on uses in physics and other uses in mathematics besides degrees of freedom. At present, it doesn't mention these and it goes into an in-depth discussion of dimension as used to mean degrees of freedom, which is a) disproportionate to the amount of space used to describe other uses in the introduction, and b) already covered in the appropriate subsection. I find your statement that it "does not present an interpretation" to be puzzling - it's _supposed_ to give an overview of _all_ interpretations, and does so (with the exceptions noted above). The key word here is overview. An introduction is the first thing that a reader will see. The first decision they make is whether to bother reading it. The second decision they make, after reading it, is whether to read any of the rest of the article. If the introduction is overly-long, it won't get read, and the user will either skim at random or move on to another article. If it does not reflect the contents of the article (or in this case, strongly emphasizes some parts at the expense of others), the reader will make the decision to read or not read based on incomplete information. This is why the goal of an introduction is to provide a concise overview of an article's content, which I do not feel is being adequately done here. I'd modify it myself, but you appear to feel strongly about what it should look like. --Christopher Thomas 17:30, 22 November 2005 (UTC)
- I have rewritten the lede simply because it needed to be done. The previous version was just too poorly entangled with the airplane concept and needed to be abstracted. Someone qualified might want to try writing an article on the concept of position - currently there is only a disambig. -MagnaMopus 22:08, 16 January 2006 (UTC)
3D-Film
Some of the information added in this section was incorrect. The relevant info belongs to the 3-D film article. The Simpsons mention would also be better served elsewhere. Correct me if I'm wrong.--Metron4 23:25, 24 January 2006 (UTC)
Philosophical calculations - huh?
I wasn't able to make any sense out of this:
- But looking at the four dimensions starting from 1 up to 4, we can see through philosophical calculation that there might be a small question mark at the 3rd an 4th dimension. If we consider that the 3 rd dimension (depth which allows radiation).
- But we need time through which space is created in the calculative world where time involves any material action or development. If an object wants to radiate energy then that energize needs time and space to travel toward our eyes. So the 3rd dimension can only do its job when the 4th dimension is created first to allow that specific energy (radiation-3rd dim) to travel through space (4th dim) in and (with) a certain time sequence.
So I deleted it. --Alvestrand 21:36, 25 January 2006 (UTC)
Christopher Thomas's Reversion
Lestrade's deleted comments
- "...a maximum of three lines can intersect a point at right angles... according to Kant... is the reason that space has three dimensions". Shouldn't that be the other way around? That space having 3 dimensions is the reason why no more than 3 lines can intersect a point at right angles? Of course, that still leaves unanswered the reason as to why space only has (or seems to have) the 3 dimensions. Answer that one -- in a way that everyone here can agree to -- and we'll let you put anything you want on this page. Deal? Ewlyahoocom 16:36, 2 March 2006 (UTC)
Lestrade's deleted comments
- I interpreted the sentence you added as trying to make a claim that any space must have three dimensions, because of a property observed in (and unique to) our three-dimensional universe. If this is not what you meant, or what Kant meant, then by all means propose an alternate phrasing here. If it was instead intended a means of _measuring_ the number of dimensions in the universe we inhabit, then I'd again suggest altering the phrasing to make this clear, though that material is already covered in the preceding paragraphs (the number of degrees of freedom, or (alternatively) the number of non-degenerate basis vectors, required to uniquely define a location in a space is the dimensionality of that space, for spaces with integer dimensionality). --Christopher Thomas 20:14, 2 March 2006 (UTC)
Why would we be using Kant as an authority on this anyway? He is a philosopher. I very much doubt he originated the idea anyway William M. Connolley 20:16, 2 March 2006 (UTC)
Lestrade's deleted comments
- You miss the point. I don't think the idea is original to Kant. what makes you think it is? Did he ever claim it was? William M. Connolley 14:04, 3 March 2006 (UTC)
Lestrade's deleted comments
Anaglyph
this section needs its tone revised
- any reason to not just delete it? it's covered adequately elsewhere, and doesn't seem to add to the subject of this article. --Alvestrand 05:51, 5 September 2006 (UTC)
Penrose Section
With the thought that someone might be interested in Penrose's singularity theorem, I added a section on it to the article. This was done in spite of the fact that the Wikipedia article on Roger Penrose states that one of the predicates associated with him is that of being a philosopher. It is therefore moot whether he may be considered to be an authority on the subject.Lestrade 13:26, 7 March 2006 (UTC)Lestrade
- I have more trouble with the fact that the article about the book doesn't mention the theorem at all, and only says that Penrose was "skeptical" towards string theory. Can you put the info on the theorem into the book description? --Alvestrand 12:16, 24 September 2006 (UTC)
Dimension and exponentiation
There is a discussion at the ref desk about whether raising to a different power expresses a different dimension. If you want to contribute, be quick, because these discussions die out in a few days. DirkvdM 08:58, 4 September 2006 (UTC)
Vandalism
If you look at sections 4, 4.2, and 4.4.1 there seems to be some vandalism there. 24.185.25.78 02:49, 23 October 2006 (UTC)
Innacuracy in diagram
This diagram is extremely innacurate for the 0th and 1st dimension. Even the slightest thickness of a 0 dimensional object would make it one dimensional. An actual one dimensional shape should be an infinitely small point. Any thickness of a one dimensional line would make it two dimensional. An actual one dimensional shape should be an infinitely thin line. Fredil Yupigo 00:25, 26 October 2006 (UTC)
Removed "Imagining the Tenth Dimension" link
My reasons:
- 1. It's primarily designed to sell a book on the subject,
- 2. It's pseudoscientific, and unaccepted by the majority of the scientific community, and,
- 3. It's not mentioned elsewhere in the article. illspirit|talk 04:54, 10 November 2006 (UTC)
I very much agree with your reasons and have just removed the link. It hurts Wikipedia's credibility to have these kinds of links. Mdmkolbe 04:10, 4 January 2007 (UTC)
Narcissism?
I've been removing this poorly-written, (apparently) ideologically driven section. It needs the following to reappear: coherent style, sources, and NPOV. 129.171.233.29 18:09, 12 January 2007 (UTC)
I will not replace this section. It contains a very basic (even if unorthodox) observation, so it would be hard to find a citation that would make it conform to NOR. It was, however, entirely coherent, and was no more ideological than any other contribution. SemblaceII 20:27, 12 January 2007 (UTC)