tag:blogger.com,1999:blog-22973357.post8186238994753476402..comments2023-09-27T07:44:19.769-04:00Comments on Sabine Hossenfelder: Backreaction: What is Fundamental?Sabine Hossenfelderhttp://www.blogger.com/profile/06151209308084588985noreply@blogger.comBlogger66125tag:blogger.com,1999:blog-22973357.post-48760146149499098052010-01-24T17:53:19.549-05:002010-01-24T17:53:19.549-05:00"A theory is fundamental if it cannot be deri..."A theory is fundamental if it cannot be derived from a more complete theory,..."<br /><br />While the theory of point sets is said to constitute the fundamental of mathematics, the whole building of mathematics seems to have worked quite well or even with less paradoxes without it. G. Cantor admitted having got his CH directly from god. Are arbitrarily stated axioms fundamental just Eckard Blumscheinnoreply@blogger.comtag:blogger.com,1999:blog-22973357.post-7884424036122451102009-07-27T03:54:20.417-04:002009-07-27T03:54:20.417-04:00Dear Arun,
now you have confused me
I don't ...Dear Arun,<br /><br />now you have confused me<br /><br /><i>I don't think anyone has looked at the question of how many different ways the **same** low-energy world can be derived from different string-scale structures -</i><br /><br />I thought the idea of "multiple realizations" was the other way 'round: same fundamental structure, different low-energy world (ashtray). There Sabine Hossenfelderhttps://www.blogger.com/profile/06151209308084588985noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-82037675099039386482009-07-26T15:46:05.001-04:002009-07-26T15:46:05.001-04:00On the most fundamental level, it has been proven ...On the most fundamental level, it has been proven that Gnome quanta explain all aspects of physics, including string theory and quantum gravity.<br /><br />See here: <a href="http://uncyclopedia.wikia.com/wiki/Physics_doesn't_exist,_it's_all_about_Gnomes" rel="nofollow">uncyclopedia.wikia.com/wiki/Physics_doesn't_exist,_it's_all_about_Gnomes</a>Williamhttps://www.blogger.com/profile/15991841830350137397noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-19766400464270487782009-07-26T14:08:45.876-04:002009-07-26T14:08:45.876-04:00Dear Bee,
Thanks for taking the time to read my l...Dear Bee,<br /><br />Thanks for taking the time to read my link. Please note that I am always attracted to physics precisely because of its fundamentalness as in your definition. Still, I think it needs to be kept in mind that the world could be different.<br /><br />"Multiple realizations" is a philosophical idea, which may or may not be relevant to the real world. Only science can Arunhttps://www.blogger.com/profile/03451666670728177970noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-4173482912544471682009-07-26T10:10:14.140-04:002009-07-26T10:10:14.140-04:00http://arunsmusings.blogspot.com/2009/07/fundament...<a href="http://arunsmusings.blogspot.com/2009/07/fundamental-science.html" rel="nofollow">http://arunsmusings.blogspot.com/2009/07/fundamental-science.html</a>Arunhttps://www.blogger.com/profile/03451666670728177970noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-6889576265831016202009-07-21T03:19:28.790-04:002009-07-21T03:19:28.790-04:00Hi Neil',
Thanks. I was wondering if I had us...Hi Neil',<br /><br />Thanks. I was wondering if I had used the expression wrongly for several years. This has happened in a couple of cases, very embarrassing if you finally figure it out. The issue with "customary usage that you get from being around" is non-trivial if you spend most of your time in an English speaking environment, but constituted mostly of people for whom English Sabine Hossenfelderhttps://www.blogger.com/profile/06151209308084588985noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-67571166633757068162009-07-20T17:26:07.824-04:002009-07-20T17:26:07.824-04:00Bee,
That Swedish guy surely made just the sort o...Bee,<br /><br />That Swedish guy surely made just the sort of mistake I was talking about. "Go ahead" in English means, to proceed with doing something (maybe from coach drivers etc. being told to "go on ahead", where ahead is the path in front of you.) But he must have heard the "go" which often means to go away (from the speaker saying that), and then thought "Neil Bateshttps://www.blogger.com/profile/04564859009749481136noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-28304629538814060102009-07-20T10:46:52.298-04:002009-07-20T10:46:52.298-04:00Hi Neil',
More precisely what I was saying is...Hi Neil',<br /><br />More precisely what I was saying is that logic is necessary, but not sufficient, much like mathematics isn't a theory but a language.<br /><br />I certainly miss a lot of subtleties of the English language (as I miss those of dozens of other languages presumably). The prime reason is that I have no chance to ever learn them since nobody ever corrects me. Thus, I'Sabine Hossenfelderhttps://www.blogger.com/profile/06151209308084588985noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-8141691582630892182009-07-20T10:10:03.472-04:002009-07-20T10:10:03.472-04:00Bee, thanks for "bearing with me." Well,...Bee, thanks for "bearing with me." Well, you indeed acknowledge above and earlier that you think there is no intrinsic, logically <i>a priori</i> reason for the universe to have to be a certain way. I don't think there is either, other than IMHO very speculative anthropic design issues which aren't formally scientific.<br /><br />But I mention the distinction since there are Neil Bateshttps://www.blogger.com/profile/04564859009749481136noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-86296986883476149162009-07-20T07:14:01.281-04:002009-07-20T07:14:01.281-04:00Hi Neil',
I have no clue what you are trying ...Hi Neil',<br /><br />I have no clue what you are trying to say. What do you mean with I'm leaving you with the impression "there isn't an a priori theoretical/conceptual reason for imagining what fundamental constituents the universe starts with." I'm not a neuroscientist, I don't know if there's a reason why humans try to find fundamental explanations for the Sabine Hossenfelderhttps://www.blogger.com/profile/06151209308084588985noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-56291560933190229962009-07-19T18:08:05.563-04:002009-07-19T18:08:05.563-04:00Bee,
You give the impression there isn't an a...Bee,<br /><br />You give the impression there isn't an a priori theoretical/conceptual reason (what would it be "based on" anyway ...) for imagining what fundamental constituents the universe starts with. But some thinkers have tried, and still believe there is an ultimate proto-theory (from logical consistency?) that could in principle tell us what's going to be there. That Neil Bateshttps://www.blogger.com/profile/04564859009749481136noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-56710545994126837312009-07-19T06:59:20.106-04:002009-07-19T06:59:20.106-04:00.....he was specifically talking about physical la...<i>.....he was specifically talking about physical laws and processes that would induce an effective metric</i>PlatoHagelhttps://www.blogger.com/profile/00849253658526056393noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-44456696184292555702009-07-19T05:27:22.142-04:002009-07-19T05:27:22.142-04:00Yes of course Bee. How it could be otherwise? Theo...Yes of course Bee. How it could be otherwise? Theories is all we have in that respect. No contemporary experiment could proclaim an entity as fundamental only a theory can.Giotisnoreply@blogger.comtag:blogger.com,1999:blog-22973357.post-40928873850077107672009-07-19T02:39:10.314-04:002009-07-19T02:39:10.314-04:00Hi Giotis,
And where we disagree then?
Well, you...Hi Giotis,<br /><br /><i>And where we disagree then?</i><br /><br />Well, you can of course define whatever you like. What I am trying to tell you is that the notion of a "fundamental concept" is useless and meaningless by itself. Your definition only makes sense because you implicitly use the definition of a fundamental theory. But strip that away, take only your "concept" Sabine Hossenfelderhttps://www.blogger.com/profile/06151209308084588985noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-56287840951089690532009-07-19T02:32:39.938-04:002009-07-19T02:32:39.938-04:00Hi Neil,
Well, the guide is, as always, Nature. I...Hi Neil,<br /><br />Well, the guide is, as always, Nature. If a theory explains everything, then it explains everything, and no need to ask further. Best,<br /><br />B.Sabine Hossenfelderhttps://www.blogger.com/profile/06151209308084588985noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-85880775912661686932009-07-19T02:32:16.269-04:002009-07-19T02:32:16.269-04:00Dear Arun,
I never said it has to be "adequa...Dear Arun,<br /><br />I never said it has to be "adequate" or even useful to have a more fundamental theory. It certainly in most cases isn't. Eg even if we would manage to derive biology from quantum field theory, I doubt that would be particularly handy. Thus, yes, my definition doesn't take this into account at all. Best,<br /><br />B.Sabine Hossenfelderhttps://www.blogger.com/profile/06151209308084588985noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-76589702578108532552009-07-19T00:30:29.514-04:002009-07-19T00:30:29.514-04:00You have to know what Hooft meant when he talked a...You have to know what Hooft meant when he talked about a "theoretical Physicist" and the skyscraper. It all had to be inclusive Uncle Al, and so too, objective recognition of what is postulated by, what transpired into the continuity of movement(now what is real), yet is not geometrically pinpointed(so Clifford throws up his hands as to what geometrically this means) seen.<br /><br /><aPlatoHagelhttps://www.blogger.com/profile/00849253658526056393noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-41919833173277525552009-07-19T00:13:56.213-04:002009-07-19T00:13:56.213-04:00I should have you know these are not real people i...I should have you know these are not real people in the dialogue below.<br /><br /> The inventor of this Dialogue copied the format from my own dialogues to bring perspective to a place where it had not existed before.:)<br /><br /><a href="http://www.mathpages.com/home/kmath632/kmath632.htm" title=" I decided to appear openly in the theater of the world as a witness of the sober truth.-Galileo, PlatoHagelhttps://www.blogger.com/profile/00849253658526056393noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-91563192427171159252009-07-18T14:26:17.766-04:002009-07-18T14:26:17.766-04:00Hi Stefan,
I managed to read Clifford's post....Hi Stefan,<br /><br />I managed to read Clifford's post. Indeed he is talking about the fundamental "ways of nature" if I may say, common in different regimes and not necessarily connected to a specific theory. <br /><br />For what is worth, my opinion is that it is an interesting idea but too vague and I'm not sure if such a notion can be trusted at all.Giotisnoreply@blogger.comtag:blogger.com,1999:blog-22973357.post-7347131436054517642009-07-18T14:12:44.081-04:002009-07-18T14:12:44.081-04:00Dear Bee,
My last try for now. Your relationship ...Dear Bee,<br /><br />My last try for now. Your relationship "Theory A is derivable from Theory B" misses out that Theory B in general will not be an adequate explanation for the phenomena described by Theory B. Quantum mechanics has very little to say about von Neumann machines, for instance.<br /><br />Best,<br />-ArunArunhttps://www.blogger.com/profile/03451666670728177970noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-24793183634216531522009-07-18T13:30:28.759-04:002009-07-18T13:30:28.759-04:00Thanks Bee,
Actually I don't think fundamenta...Thanks Bee,<br /><br />Actually I don't think fundamental "string" and violin strings are the same sort of thing, I was doing "comparison and contrast" to show the difference too. The difference is of the essence, it's the implications of the difference I care about.<br /><br />Yes of course strings aren't like the macroscopic variety, my point is: what guide have Neil Bateshttps://www.blogger.com/profile/04564859009749481136noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-13187997143528787212009-07-18T12:47:45.131-04:002009-07-18T12:47:45.131-04:00And where we disagree then? I stated explicitly in...And where we disagree then? I stated explicitly in my comment:<br /><br />"A fundamental concept (or entity) is what you postulate in your theory. Something you can't derive."<br /><br /><br />The issue is that I thought you were saying that it doesn't make sense to talk about fundamental concepts *within* the theory.<br /><br />My argument was that any fundamental theory must Giotisnoreply@blogger.comtag:blogger.com,1999:blog-22973357.post-27141531789493232872009-07-18T12:17:07.247-04:002009-07-18T12:17:07.247-04:00Hi Neil',
If String Theory is the fundamental...Hi Neil',<br /><br />If String Theory is the fundamental theory of everything then the point is there is no "more fundamental" description of a string. It isn't "made up" of anything, it just is. Period. That's exactly what it means to be fundamental (Davies' levitating super-turtle - it doesn't stand on anything). Your problem is that the analogy to Sabine Hossenfelderhttps://www.blogger.com/profile/06151209308084588985noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-76987881005267984882009-07-18T11:38:47.531-04:002009-07-18T11:38:47.531-04:00Hi Neil,
Yes it is kind of ironic, that for years...Hi Neil,<br /><br />Yes it is kind of ironic, that for years physics has considered that part of the final explanation must show that reality comes with no strings attached, that the explanation being it is all strings for which it is required a reality to attach themselves to. So we are now asked to believe in a reality with both instruments and meaningful music, yet with having no composer or Phil Warnellhttps://www.blogger.com/profile/15671311338712852659noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-54470070390901269392009-07-18T11:14:11.292-04:002009-07-18T11:14:11.292-04:00Here's something that I suppose must be "...Here's something that I suppose must be "fundamental" - what "works" strings in string theory. A "real string" like from a violin is made of constituent atoms, and we can predict the behavior of that string from laws about those constituents. But a "string" in ST is just as is, with no "components" I suppose (?) So what "runs the string&Neil Bateshttps://www.blogger.com/profile/04564859009749481136noreply@blogger.com