4 ms·

So what's wrong with Lavoisier being credited with the Law of Conservation of Mass? He is famous enough for it that I, having no formal training in physics, am

by mowenz 9y ago

So what's wrong with Lavoisier being credited with the Law of Conservation of Mass? He is famous enough for it that I, having no formal training in physics, am aware of him discovering it independently. The author may be right (or wrong) but he is not right or wrong due to whatever epaulletes he is wearing on his uniform. It does signal he is likely right, but in that case we should point to the reason and not just point to at the epaulettes.

pvg 9y ago
Nothing, other than the fact the author is not talking about Lavoisier's law and that it's more than a little presumptuous to be telling someone who teaches physics at MIT, beside collecting a Nobel prize, that they might wish to check Wikipedia (ceremoniously [1]-footnoting it, in two lines of text) for the historical perspective they might lack. Yes of course the author can be wrong about something - the comment isn't pointing out anything wrong, just sententiously insinuating he is uninformed.
- mowenz 9y ago
  Then you can enlighten us because as far as we can tell what we think you are saying is the author's discussion of conservation of mass has nothing to do with the Law of Conservation of Mass (as opposed to some mystic qualities of matter believed prior to the discovery of this law of nature--in classical physics). Don't just point to the epaulettes and tell him to be respectful--it's ok to question authority (granted it was done a little bit presumptiously, you are right there, but I'd recommend letting it go--be the bigger person and be the teacher).
  - pvg 9y ago
    I'm not 'pointing to epaulettes. I am pointing out the silly and unwarranted assumption Frank Wilczek is unaware of the basic, Wikipedia-page-level history of the science in question. I think it's obvious and a given that he is. If you don't think that's the case, fair enough but it's up to you to find some concrete way to support that rather odd view - it's not for me to refute it from first principles.
    - mowenz 9y ago
      We're not asking you to defend this physicist. There's an obviously confusing bit about conservation of mass here, which lead to the user citing the Law of Conservation of Mass, that I already asked about, and which you are now ignoring. That's the thing to focus on, not on Frank Wilczek. We already know the poster (unwittingly) was a bit presumptious, but in my opinion I think it would be better to focus on the ideas and let the presumptiousness just slide.
      - pvg 9y ago
        What's the confusing bit?
        mowenz 9y ago
        What's remarkable about conservation of mass in the author's example that's not already formulized in the Law of Conservation of Mass?
        pvg 9y ago
        Which law? You mentioned Lavoisier and I think someone else already covered this well. It's hard to figure out what your question is from your strident defense of 'someone is being an ass on messageboards'.
        mowenz 9y ago
        I think you're taking taking it personally, and beginning to use inflammatory language. I think you are thinking emotionally about this and that is why you are misinterpreting my thoughts. Wiczek himself thinks it's an unintuitive notion to question such an assumpion. Yes the poster didn't pose it as a question. We already agree that is presumptious, and a mistake. Where we disagree is the bigger mistake is in not explaining the poster's confusion. I don't think you or anyone is being an "ass." Let's take a cooling off period from this so we don't get upset over some small disagreement on the value of deferring to faith in authority.
  - yequalsx 9y ago
    I tend to give the benefit of the doubt to experts in such situations. While I too thought of the Law of Conservation of Mass and wondered why the author didn't think of it I also know this means that most likely it is I who is lacking knowledge in this case. It is highly unlikely that I know something about mass that an expert doesn't know. Rather than linking to Wikipedia the question ought to have been asked, "what does he mean when he writes this?" Instead amelius says he should read Wikipedia. Let's not pretend that our superficial understanding matches the expert's understanding or that we can teach him something new by citing Wikipedia. If we can think of a point that the author seemingly misses it is almost surely because we are the ones not understanding something.
    - mowenz 9y ago
      We actually don't disagree here; at least not on the points you listed. It appears you are misunderstanding what I'm trying to say. While we both agree it is reasonable to give the benefit of the doubt to experts, and it wasn't good to be a bit presumptiois either, the issue is that we should still never answer by just pointing to the epaulettes of the expert--especially in this case where there is an obvious confusion. I don't believe this physicist would be offended by Amelius' post, and if an authority was offended by such a minor transgression and first unwilling to provide an explanation--as was the case here--and sought to assert authority instead of through explanation and through epaulettes, we should further question that authority, always. We could next time just say: 'here is why you are confused, and you should have wondered why if you happened to notice the writer's accomplishment.'
      - pvg 9y ago
        The poster never said they were confused. They implied the author was confused. You seem really keen on berating others about 'epaulettes' while taking it on faith the poster was actually asking a question, rather than being a butthead. There is no evidence of that whatsoever. How on earth is anyone supposed to figure out what question is being asked in the in the intricate disguise of being a butthead?
        9y ago
andars 9y ago
The key words are "in classical mechanics." Nobody wondered whether the mass of two stacked bricks was equal to the sum of the masses of the individual bricks. On the other hand, burning cloth seems to "leave behind" a lot less than you started with. Lavoisier's contribution was to demonstrate that even in chemical reactions, with shocking changes in color, state of matter, etc, mass was conserved. Wilczek is discussing the ingrained assumption about the bricks.
- mowenz 9y ago
  We're familiar with Lavoisier's Law. So when you are suggesting CM, many of us probably know that Lavoisier's Law would show small errors at high energy states in CM... But then your explanation offers some perspective on Lavoisier's Law... So what are you suggesting with your key word?
Mvandenbergh 9y ago
In the context of chemistry, conservation of mass is not at all obvious which is why it is a big deal that Lavoisier proved it to be the case. To determine that burning wood into ash (for instance) doesn't change the total mass of the system requires precise measurement and an intuitive leap on what constitute the boundaries of the system. In mechanics there is historically no such law precisely because no-one would ever have thought that it wasn't obviously true.
- mowenz 9y ago
  Yes I am aware. The issue is that in our current understanding we now know in chemistry we are adding element1+element2=element1+element2... (classically at least). So while Lavoisier led us to the above, the author is pointing to the fact that e1+e2=e1+e2 but to the reader this can be confusing because Lavoisier's Law also states the same... Though once you understand that you are just rearranging chemical bonds b/w elements there's nothing different about it. I don't have any intuition about how you would theoretically prove the assumption in Lavoisier's Law--Newton's 0th Law. It seems if Lavoisier's Law is true it implies Newton's 0 must also, at least intuitively... It's a reasonable source of confusion and I think it's ok the above poster was misguided about it as everyone agrees from the start on this: almost no one questioned such an assumption.

by mowenz 9y ago

pvg 9y ago

Nothing, other than the fact the author is not talking about Lavoisier's law and that it's more than a little presumptuous to be telling someone who teaches physics at MIT, beside collecting a Nobel prize, that they might wish to check Wikipedia (ceremoniously [1]-footnoting it, in two lines of text) for the historical perspective they might lack. Yes of course the author can be wrong about something - the comment isn't pointing out anything wrong, just sententiously insinuating he is uninformed.

mowenz 9y ago
Then you can enlighten us because as far as we can tell what we think you are saying is the author's discussion of conservation of mass has nothing to do with the Law of Conservation of Mass (as opposed to some mystic qualities of matter believed prior to the discovery of this law of nature--in classical physics). Don't just point to the epaulettes and tell him to be respectful--it's ok to question authority (granted it was done a little bit presumptiously, you are right there, but I'd recommend letting it go--be the bigger person and be the teacher).
- pvg 9y ago
  I'm not 'pointing to epaulettes. I am pointing out the silly and unwarranted assumption Frank Wilczek is unaware of the basic, Wikipedia-page-level history of the science in question. I think it's obvious and a given that he is. If you don't think that's the case, fair enough but it's up to you to find some concrete way to support that rather odd view - it's not for me to refute it from first principles.
  - mowenz 9y ago
    We're not asking you to defend this physicist. There's an obviously confusing bit about conservation of mass here, which lead to the user citing the Law of Conservation of Mass, that I already asked about, and which you are now ignoring. That's the thing to focus on, not on Frank Wilczek. We already know the poster (unwittingly) was a bit presumptious, but in my opinion I think it would be better to focus on the ideas and let the presumptiousness just slide.
    - pvg 9y ago
      What's the confusing bit?
      - mowenz 9y ago
        What's remarkable about conservation of mass in the author's example that's not already formulized in the Law of Conservation of Mass?
        pvg 9y ago
        Which law? You mentioned Lavoisier and I think someone else already covered this well. It's hard to figure out what your question is from your strident defense of 'someone is being an ass on messageboards'.
        mowenz 9y ago
        I think you're taking taking it personally, and beginning to use inflammatory language. I think you are thinking emotionally about this and that is why you are misinterpreting my thoughts. Wiczek himself thinks it's an unintuitive notion to question such an assumpion. Yes the poster didn't pose it as a question. We already agree that is presumptious, and a mistake. Where we disagree is the bigger mistake is in not explaining the poster's confusion. I don't think you or anyone is being an "ass." Let's take a cooling off period from this so we don't get upset over some small disagreement on the value of deferring to faith in authority.
- yequalsx 9y ago
  I tend to give the benefit of the doubt to experts in such situations. While I too thought of the Law of Conservation of Mass and wondered why the author didn't think of it I also know this means that most likely it is I who is lacking knowledge in this case. It is highly unlikely that I know something about mass that an expert doesn't know. Rather than linking to Wikipedia the question ought to have been asked, "what does he mean when he writes this?" Instead amelius says he should read Wikipedia. Let's not pretend that our superficial understanding matches the expert's understanding or that we can teach him something new by citing Wikipedia. If we can think of a point that the author seemingly misses it is almost surely because we are the ones not understanding something.
  - mowenz 9y ago
    We actually don't disagree here; at least not on the points you listed. It appears you are misunderstanding what I'm trying to say. While we both agree it is reasonable to give the benefit of the doubt to experts, and it wasn't good to be a bit presumptiois either, the issue is that we should still never answer by just pointing to the epaulettes of the expert--especially in this case where there is an obvious confusion. I don't believe this physicist would be offended by Amelius' post, and if an authority was offended by such a minor transgression and first unwilling to provide an explanation--as was the case here--and sought to assert authority instead of through explanation and through epaulettes, we should further question that authority, always. We could next time just say: 'here is why you are confused, and you should have wondered why if you happened to notice the writer's accomplishment.'
    - pvg 9y ago
      The poster never said they were confused. They implied the author was confused. You seem really keen on berating others about 'epaulettes' while taking it on faith the poster was actually asking a question, rather than being a butthead. There is no evidence of that whatsoever. How on earth is anyone supposed to figure out what question is being asked in the in the intricate disguise of being a butthead?
      - 9y ago

andars 9y ago

The key words are "in classical mechanics." Nobody wondered whether the mass of two stacked bricks was equal to the sum of the masses of the individual bricks. On the other hand, burning cloth seems to "leave behind" a lot less than you started with. Lavoisier's contribution was to demonstrate that even in chemical reactions, with shocking changes in color, state of matter, etc, mass was conserved. Wilczek is discussing the ingrained assumption about the bricks.

mowenz 9y ago
We're familiar with Lavoisier's Law. So when you are suggesting CM, many of us probably know that Lavoisier's Law would show small errors at high energy states in CM... But then your explanation offers some perspective on Lavoisier's Law... So what are you suggesting with your key word?

Mvandenbergh 9y ago

In the context of chemistry, conservation of mass is not at all obvious which is why it is a big deal that Lavoisier proved it to be the case. To determine that burning wood into ash (for instance) doesn't change the total mass of the system requires precise measurement and an intuitive leap on what constitute the boundaries of the system. In mechanics there is historically no such law precisely because no-one would ever have thought that it wasn't obviously true.

mowenz 9y ago
Yes I am aware. The issue is that in our current understanding we now know in chemistry we are adding element1+element2=element1+element2... (classically at least). So while Lavoisier led us to the above, the author is pointing to the fact that e1+e2=e1+e2 but to the reader this can be confusing because Lavoisier's Law also states the same... Though once you understand that you are just rearranging chemical bonds b/w elements there's nothing different about it. I don't have any intuition about how you would theoretically prove the assumption in Lavoisier's Law--Newton's 0th Law. It seems if Lavoisier's Law is true it implies Newton's 0 must also, at least intuitively... It's a reasonable source of confusion and I think it's ok the above poster was misguided about it as everyone agrees from the start on this: almost no one questioned such an assumption.