90 reputation
217
bio website math.stackexchange.com/users/…
location Champaign, IL
age 36
visits member for 4 years, 3 months
seen May 11 at 21:41

Amateur mathematician, professional software engineer. Interested in all kinds of math, becoming a better mathematician, and helping others do the same.

email: jdb1729 (at) gmail.com

let's be friends: http://facebook.com/jdb1729


May
26
comment Atomic mass of Copper-63?
Furthermore I have a personal interest in learning more about how to do this sort of research in general. C Earnest's answer is my favorite so far. user9325's answer simply shows that one of the URLs contradicts its own extra data, but that is no reason to accept the 62.929 value; it is only a reason to reject the other. On the other hand, all the other answers support the 62.929 value with secondary sources.
May
26
comment Atomic mass of Copper-63?
Luboš, if you read the comment threads that I have linked to, you will see that people are attempting to debunk this cold-fusion claim on the basis of this typo. Whether or not you believe in this nonsense it paints physicists and the discipline of physics in a poor light. My motivation in asking this question is to provide a better reference than NIST for this value so that this mistake will not be repeated in future discussions. I wholeheartedly believe that SE is capable of this.
May
26
comment Why is global conservation of energy not considered a tautology?
Yet another way to phrase this objection: isn't it the case that both the assertion and denial of conservation of energy are philosophical and not physical statements? I find the former more palatable because it is true in everyday experience and were it to be demonstrated otherwise, "energy gods" is a short string compared to any long proof that conservation of energy is violated on the basis of some other unproven theory. So it is either conservation or energy gods by Occam's razor.
May
26
comment Why is global conservation of energy not considered a tautology?
I hope that idea isn't too silly for this site but my question is essentially philosophical and I think the thought experiment of a perpetual motion machine requires some specific context for it to make any sense. I think an equivalent question is: does the falsification of energy conservation require the ability to independently and repeatedly replicate that falsification experiment?
May
26
comment Why is global conservation of energy not considered a tautology?
This is a helpful and intellectually honest answer. It will take me some time to finish studying it but I have one immediate concern: suppose the hypothetical free-energy machine is a singleton i.e. it has only one discovered instance. Fancifully let's say it is discovered buried on the moon like the monolith in the movie "2001". So it is not a thing which can be replicated by any known means. Would it still be the case that scientists would can the law of conservation of energy rather than ascribe its power to the energy gods? Why should they assume there are any more instances of it?
May
26
revised Why is global conservation of energy not considered a tautology?
typo
May
26
comment Why is global conservation of energy not considered a tautology?
wsc, the point is that there is no reason not to describe it as coming from "somewhere else". And there is at least one reason to describe it that way: we still have conservation of energy. I don't think the argument assumes its own conclusion as you suggest; it assumes that we have some pre-existing theory which cannot explain the extra energy, and constructs a new theory that can explain it. Whenever conservation of energy is violated we just fix the theory. GR and QM are falsifiable but how is conservation of energy falsifiable?
May
26
comment Why is global conservation of energy not considered a tautology?
This seems like saying that a statement isn't true unless it is provable, or that a number isn't real unless it is computable, but both are false assuming the consistency of the formal system. Why can't we see energy as something more primitive than the theories which attempt to provide methods to measure it? Just because global energy isn't defined in GR doesn't mean it doesn't exist, it just means GR is incomplete (which I guess we already know because it seems to have little to say about QM).
May
26
revised Why is global conservation of energy not considered a tautology?
add tags
May
26
asked Why is global conservation of energy not considered a tautology?
May
25
comment Conservation law of energy and Big Bang?
Luboš and Jerry, I'm far out of my league in this thread and a few times it seems that I've spoken when I should have been listening. I still believe there is a semantic issue here and I've updated my own answer to reflect that. Thank you both for the informative explanations.
May
25
revised Conservation law of energy and Big Bang?
remove wrongness
May
25
revised Conservation law of energy and Big Bang?
answer question more directly
May
25
revised Conservation law of energy and Big Bang?
fix typo
May
25
comment Conservation law of energy and Big Bang?
I think that "energy is not conserved" and "energy is meaningless and doesn't really exist" are different statements. I can't tell which one you are supporting.
May
25
comment Conservation law of energy and Big Bang?
I guess I can accept the silly idea that energy is ultimately meaningless, i.e. energy does not exist. But that is incompatible with the non-conservation of energy, which pre-supposes its existence. I maintain that "energy is not conserved" is tautologically false, in GR or otherwise.
May
25
revised Conservation law of energy and Big Bang?
remove special-relativity tag
May
25
suggested approved edit on Conservation law of energy and Big Bang?
May
25
revised Conservation law of energy and Big Bang?
add tag special-relativity
May
25
suggested approved edit on Conservation law of energy and Big Bang?