Talk:Intensive and extensive properties

message: Which is the correct term in physics / chemistry:
:intrinsic/extrinsic
or
:intensive/extensive?
I've seen both usages. The Anome
:I have only seen intensive/extensive. Chadloder 09:42 Apr 1, 2003 (UTC)
Extensive makes more sense to me, because it's about something being extended.  Michael Hardy 21:29, 5 August 2005 (UTC)
thread_title: Correct term

message: Removed 'vagility' as entirely inappropriate.  It is a biological term.  If "fragility" was intended, it is a poor example to list here as it is hard to define and measure, and there is no commonly recognised use for such measurements.
On the other hand, I think the discussion on the difference between perception and physical properties should stay here. I am aware that perception is closer to a psychological topic than a physical one - but those who DO confuse the two will never understand the difference if it is tucked away under Perception or Psychology, and the function of an encyclopedia entry is to educate and inform, is it not?
The comment about "pressure" being in the wrong place has been corrected by putting it where it belongs, and removing the comment.
202.61.162.14 12:51, 8 May 2006 (UTC)
thread_title: Removed and kept

message: I note a merge notice suggesting that bulk property be merged into this article. Is 'intensive property' really a more common usage than 'bulk property'? In quite a few years of science and engineering (with a fair bit of material properties) I've overwhelmingly heard 'bulk'. Some of this might be regional variance, but Googling gets slightly more hits for +"bulk property" than +"intensive property" (787 vs. 739, if you click to the end). ('Extensive' seems to be the antonym of choice in either case.)
Unless there's a reason to favour 'intensive', I would instead suggest renaming this article to bulk and extensive properties, acknowledging 'intensive' and 'bulk' as synonyms, and turning both bulk property and intensive property into redirects. --Calair 02:25, 9 August 2006 (UTC)
thread_title: 'Bulk' vs. 'intensive'?

message: I just wanted to say that I support the merges suggested on the page. Whether or not this article is ultimately called bulk and extensive or intensive and extensive is pretty unimportant to me. For what it's worth, the terminology being used in my thermo class is intensive. That being said, there is information in the intensive and extensive quantity articles that could be incorporated into this one to improve it. If I get some time here, I'll go ahead and try to add to this one. !jim 02:28, 14 October 2006 (UTC)
thread_title:  Merge 

message: From the standpoint of physics, especially that of the statistical variety, the term "intensive" is most commonly used.  Most of the classic textbooks (i.e. Reif) and current work in generalized entropies use intensive/extensive, so such a usage would provide more consistency with established literature.  Futher, from a more linguistic point of view, the phrase "intensive and extensive" pair together better than "bulk and exensive"; the change in prefix makes it clear that you're talking about the two sides of a single coin.  The colloquial usage of the term "bulk", at least to me, violates what's meant by an intensive/bulk property in its technical usage.  I hear bulk and I think "most of, if not, the whole thing" when in fact what we mean is "whatever bit you pick out from the whole thing, no matter how tiny".  For that reason I favor a merge to "Intensive and extensive properties".  Pgriffin 16:52, 13 September 2006 (UTC)
replies: text: Fair enough. I agree that 'intensive and extensive' is more aesthetic, and it's common enough to be a reasonable choice. Merge/redirecting to here seems reasonable. --Calair 01:29, 28 September 2006 (UTC)

text: Indeed, the colloquial concept of a "bulk" property would actually be an extensive quantity. How confusing! Cesiumfrog (talk) 04:26, 9 August 2010 (UTC)
thread_title:  Physics favors intensive 

message: So, which one is it, an intensive or an extensive property? --No_body 21:07 October 2008 (XYZ)  —Preceding unsigned comment added by 76.27.197.169 (talk) 04:07, 18 October 2008 (UTC)
replies: text: Resistance is extensive, resistivity is intensive. --144.53.226.17 (talk) 05:19, 5 February 2009 (UTC)

text: Actually as explained in the section on Counterexamples, resistance is only extensive for resistors connected in series. In general it is neither extensive nor intensive. Resistivity however is intensive as stated above. Dirac66 (talk) 01:14, 7 March 2013 (UTC)
thread_title:  Electrical Resistance 

message: The link had been one-way.Rainbow-five (talk) 22:56, 23 October 2008 (UTC)
replies: text: Stiffness does not fullfil the requirements of being extensive since it is not always proportional to the size of the system. E.g. a rod of twice the length has half the stiffness. I have removed it as an example. Ulflund (talk) 18:49, 14 September 2011 (UTC)
thread_title:  Adding Stiffness 

message: I am amazed that there is only one mention of the concept of quality in this article, short as it is -- and it's practically an aside, at that. Of course, the article also reeks of bourgeois reductionist logic, and not dialectical-materialism. Not unusual for Wikipedia's science topics.  —Preceding unsigned comment added by Pazouzou (talk • contribs) 17:27, 14 June 2010 (UTC)
thread_title:  Quality vs. Quantity 

message: Today Kbrose changed the two lists of example intensive and extensive properties to a 3-column format. This is a good idea for long lists of short items, except that with Internet Explorer 7.0 it doesn't work and the lists still appear as 1-column. For Mozilla Firefox 3.6 on the other hand it does work and the lists look much nicer. I have no idea why the difference. Dirac66 (talk) 18:02, 13 August 2010 (UTC)
thread_title:  Browser-dependent list layout 

message: Are these terms used in economics, or just in the physical sciences? For example, the difference between gross domestic product (GDP) and GDP per capita resembles the difference between mass and density. --Damian Yerrick (talk | stalk) 23:16, 18 February 2011 (UTC)
replies: text: I think these terms apply equally to economics, for example: Q (quantity per period) and p (unit price).  Their usage may not be widespread but p-Q is no different from the natural pairs p-V or T-S. I think a comment to this effect should be added. Robbiemorrison (talk) 11:31, 20 August 2012 (UTC)
replies: text: The question is whether there are at least some economics textbooks or articles which do in fact use the terms. If so, then we can cite them as sources. If not, then there may be a formal mathematical similarity, but mentioning it would be original research which is not supposed to be in Wikipedia. See WP:OR for the policy. Dirac66 (talk) 02:05, 22 August 2012 (UTC)
thread_title:  In economics 

message: The Intensive and extensive properties#Distinction from perceptions section uses color as an example of something related to an extensive property which it is not. I would correct this but cannot think of any preception related to an extensive property. I think this section should instead be removed. Ulflund (talk) 19:09, 14 September 2011 (UTC)
replies: text: This section is really more about what is and is not a physical property, rather than about the terms intensive and extensive. I propose to move the section to the article Physical property. Then the mentions of intensive and extensive can be deleted from the section, since they are not exactly correct. Dirac66 (talk) 03:03, 15 September 2011 (UTC)
thread_title:  Distinction from perceptions 

message: According to today's edit by Incnis Mrsi: An extensive quantity is usually additive ... But there are extensive quantities for which it is not the case: invariant mass in special relativity is not additive.
I understand that invariant mass is not additive when one subsystem is moving at relativistic velocity with respect to another subsystem. However since an extensive quantity is defined as one which is additive, the consequence is that invariant mass is also not extensive under these conditions. So it is incorrect to say that invariant mass is an extensive quantity which is not additive. In fact it is both additive and extensive when relativistic effects are ignored, and it is in general neither additive nor extensive in special relativity. Dirac66 (talk) 03:16, 5 February 2012 (UTC)
replies: text: Sorry, I do not understand your point: do you see invariant mass as an example of quantity not extensive nor intensive? Is there a definition of an intensive quantity somewhat broader than "a quotient of two extensive quantities"? Incnis Mrsi (talk) 07:50, 5 February 2012 (UTC)
replies: text: Yes, invariant mass is an example of "neither extensive nor intensive". As explained in the intro, intensive means independent of the system size, which is clearly not true of invariant mass. The last section of the article (Counter-example) does explain that there are properties which are neither extensive nor intensive, using electrical resistance as one example. Invariant mass would be another counter-example, and one could find many others. Dirac66 (talk) 12:26, 5 February 2012 (UTC)
replies: text:  Well, I do not insist on my interpretation. Move it to counter-examples with appropriate explanations (probably, your English is better than mine). Incnis Mrsi (talk) 12:55, 5 February 2012 (UTC)
thread_title:  Invariant mass in special relativity 

message: I removed velocity and acceleration. Although for a rigid system that does not rotate, it's true that they are intensive, it's not true in general. For a rotating stick, the speed of the subsystems (for example, the tip of the stick) depends on the size of the stick. You add more length to it, you get more speed, if it's a constant rotation. Similar considerations go for acceleration.  — Preceding unsigned comment added by 79.119.58.54 (talk) 20:58, 21 March 2013 (UTC)
replies: text: Are you saying that the same property can be chimeric? sometimes like this sometimes opposite??? that is an example how misused and misunderstood this concept of intensiveness is and actually even shifted to overlap with additive properties (someone just annihilated this concept and renamed additiveness to extensiveness or created a synonym).  — Preceding unsigned comment added by 134.7.193.46 (talk) 13:06, 2 August 2016 (UTC)
thread_title:  Be careful what values you put there as intensive or extensive 

message: Today the point that intensive properties can vary spatially was added as the second sentence of the article. This point is true but I think it has been mentioned too soon, since it only applies to local (not global) equilibrium and is not essential to a basic understanding of the concept of intensive variable. I suggest moving this point to the section on Intensive properties, perhaps at the end of the intro to that section just after noting that certain properties are not relevant to extremely small systems. Dirac66 (talk) 18:41, 8 April 2013 (UTC)
thread_title:  Spatial variability - too soon.in article 

message: Today Kbrose deleted two of the three counterexamples with no explanation other than an edit summary saying "remove nonsense examples from 'counterexamples'". For the first counterexample, electrical resistance (R), if you believe the reasoning is incorrect, please explain why. If you believe that R is so obviously not extensive that it does not to be explained, I would point out that prior to Sept. 2011, R was included in the article as a supposedly extensive property. After removing it on 14 Sept. 2011, I decided on 8 Nov.2011 that it would be useful to some readers to explain why it is not extensive.
For the second example, length, I note that Kbrose has also inserted length into the list of extensive properties. Again this is contradicted by the reasoning just deleted from the Counterexamples section, so please explain why this reasoning is incorrect. 
I am going to restore these two counterexamples. Please do not remove them without adequate explanations. Dirac66 (talk) 15:29, 24 April 2013 (UTC)
replies: text: Frankly, you have to be joking. This can only happen on WP. You are making a laughing stock out of WP and yourself. These examples are ridiculous. Take any text book on physics and it will explain it, and indeed list length as an extensive property.  How can length not be extensive? It is one of the simplest properties.  If length is not extensive, then volume isn't either. Length is the measurement of a one-dimensional space, if you had a second subsystem, it can only be the sum of the lengths. If you are adding another yard stick in parallel to a first, you are not adding anything to the property length, in this case would you call the property 'width' extensive? If length is not extensive and width is, then please tell us how the properties width and length differ so fundamentally?    The same applies to resistance. switch two resistors in parallel vs. in series is not a valid comparison, albeit seemingly the amount of material is increasing in both. But that is clearly not the important aspect now, is it? Resistance is extensive and resistivity, i.e. 'specific' resistance, is intensive.  The entire section of 'counterexamples' should be removed.  Just what is a 'counterexample' anyways?   Kbrose (talk) 00:10, 25 April 2013 (UTC)

text: This section is still wiki-science. With enough acrobatics you can come up with a lot of things that fall outside of the definitions. That doesn't make it notable or even correct. Clearly there are a lot of mathematical functions, like the square root, that would render the concept meaningless. Clearly the square root of volume is not a new physical quantity, even if you devise a measurement that provides that reading. Volume is still volume and it does not change the property. The common understanding these days is that additive in extensive applies only to subsystem that don't interact. The article cites IUPAC sources which make it clear.  Your galvanic cells or the resistors clearly do interact and therefore one must consider the dimensionality of the problem in detail to arrive at the correct solution that both are indeed extensive properties. Clearly they are not bulk properties.
The property length in physics is always one-dimensional whether the space is linear or curved, and the comment is superfluous. This is not the common language 'length' that is simply the longest dimension of an object. You have to really have a weird point to push onto others to make such comments. Kbrose (talk) 16:26, 26 April 2013 (UTC)
thread_title:  Counterexamples are not nonsense 

message: I have now found a reliable source for some of the arguments in the recently removed Counterexamples section. A paper in J.Chem.Educ. by Otto Redlich, known for the Redlich-Kwong equation of state. He has an example of galvanic cells connected in series or in parallel, analogous to the example of electrical resistances. So I have rewritten the section with a new title and used the example of galvanic cells. I believe that the case of electrical resistance is entirely analogous but agree to use the example which is explicitly mentioned in the source article.
As for length being extensive, the physical chemistry texts I checked just give 2-3 basic examples of extensive properties such as mass and volume, plus thermodynamic properties. Yes, length is extensive IF one only considers a one-dimensional space. But my universe has three dimensions and displacements in the other two dimensions are possible also, as are rotations. So I will leave length in the list, but add in parentheses (for one-dimensional systems).
Finally for invariant mass I have no source, although the argument in the deleted section does appear to be correct. If someone finds a reliable source we can restore it. Dirac66 (talk) 22:46, 25 April 2013 (UTC)
replies: text: This section is still wiki-science. With enough acrobatics you can come up with a lot of things that fall outside of the definitions. That doesn't make it notable or even correct. Clearly there are a lot of mathematical functions, like the square root, that would render the concept meaningless. Clearly the square root of volume is not a new physical quantity, even if you devise a measurement that provides that reading. Volume is still volume and it does not change the property. The common understanding these days is that additive in extensive applies only to subsystem that don't interact. The article cites IUPAC sources which make it clear.  Your galvanic cells or the resistors clearly do interact and therefore one must consider the dimensionality of the problem in detail to arrive at the correct solution that both are indeed extensive properties. Clearly they are not bulk properties.
The property length in physics is always one-dimensional whether the space is linear or curved, and the comment is superfluous. This is not the common language 'length' that is simply the longest dimension of an object. You have to really have a weird point to push onto others to make such comments. Kbrose (talk) 16:26, 26 April 2013 (UTC)
thread_title: Source for counterexamples

message: Near the end of the introduction, the article states:
:For example, when gravity may be assumed constant, the ratio of the extensive properties mass and volume, the density, is an intensive property
I'm not a master of physics or anything, but from my understanding, isn't gravity irrelevant when discussing the ratio of mass and volume? Constant gravity would only be required if it were the ratio of weight and volume, correct? If somebody can confirm this I'd like to change the sentence to read:
:For example, the ratio of the extensive properties mass and volume, the density, is an intensive property
I think that just about any physics article is improved when gravity doesn't rear its ugly head. Dataxpress (talk) 03:52, 18 February 2015 (UTC)
replies: text: Gravity has two roles here. First, weight = mg so increasing gravity increases the weight associated with a given mass, as you realize. But there is also a second effect which becomes important for large (say planet-sized) objects - gravity pulls the mass together so that at higher gravity, the mass density itself (and not just the weight density) increases. For laboratory-sized systems the variation is negligible, but it does become important in planetary science and astronomy. Dirac66 (talk) 01:43, 19 February 2015 (UTC)
replies: text: Ah, got it. Makes sense. Thanks for the explanation. Dataxpress (talk) 21:51, 7 March 2015 (UTC)
thread_title:  Diamond example in introduction - isn't gravity irrelevant? 

message: In essence, towards the bottom of the page, it becomes an absolute clusterf*ck that is barely legible. Can someone fix this? 98.220.186.209 (talk) 17:44, 18 February 2015 (UTC)
replies: text: Fixed. The problem was that the previous edit by 193.1.30.2 deleted the colend (column end) parameter at the end of the list of examples of intensive properties. This parameter tells the system that the list of 3 columns is finished, so without it the system tried to put the whole rest of the article into a long list with 3 columns which looked terrible as you say. I have restored the missing colend. Dirac66 (talk) 00:56, 19 February 2015 (UTC)
thread_title: This page is a mess in Mozilla Firefox...

message: why all this classification of intensiveness-extensiveness was switched to additiveness-nonadditiveness??? original concept was to have additional property to this by telling witch one is space related and witch one is not (meaning time related), that is why changes in volume was chosen as a central idea (and the discrimination factor)!!!  — Preceding unsigned comment added by 134.7.193.46 (talk) 12:57, 2 August 2016 (UTC)
thread_title:  Some people confusing additiveness with extensiveness-intensiveness 

message: The lead notes that square roots are not intensive or extensive. I am wondering if the reason for this is that the exponent 1/2 for square root is not an integer and if the exponent is an integer like mass*{length}^{-3} for density there is always a clear difference between intensive and extensive. WalkingRadiance (talk) 16:29, 18 January 2023 (UTC)
thread_title:  Integer Exponents 

message: I think its interesting that if a quantity has a maximum value even if its not used in everyday life such as the Planck temperature of 10^{32} K or the speed of light, then the quantity is intensive. For example the speed of light is used to define length, and length can be used to normalize mass which is an extensive quantity to form density, which is an intensive quantity. WalkingRadiance (talk) 16:33, 18 January 2023 (UTC)
replies: text: Well, an extensive quantity cannot have a maximum value because one can obtain a larger value just by increasing the size of the system. Dirac66 (talk) 21:37, 18 January 2023 (UTC)
thread_title:  Maximum