tag:blogger.com,1999:blog-22973357.post2722885186474612673..comments2023-09-27T07:44:19.769-04:00Comments on Sabine Hossenfelder: Backreaction: This and ThatSabine Hossenfelderhttp://www.blogger.com/profile/06151209308084588985noreply@blogger.comBlogger20125tag:blogger.com,1999:blog-22973357.post-26397172611088630452010-11-04T12:02:21.306-04:002010-11-04T12:02:21.306-04:00It may comfort you to hear that I've never hea...It may comfort you to hear that I've never heard of the neutrino having a diameter either. The only thing I can think of is somebody taking the square root of the typical cross-section. These are actually energy-dependent, but for the average energies of, say, solar neutrinos, it might just fit:<br /><br />http://cupp.oulu.fi/neutrino/nd-cross.htmlSabine Hossenfelderhttps://www.blogger.com/profile/06151209308084588985noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-71276936513266265682010-11-04T10:24:31.476-04:002010-11-04T10:24:31.476-04:00Getting back to the Scales of the Universe thing ....Getting back to the Scales of the Universe thing ...<br /><br />According to the app, a yoctometer is 10^-24 m equals the alleged diameter of a neutrino (non high-energy state), which is the smallest thing that's not highly speculative, "speculative" being those things ELEVEN ORDERS of magnitude down from a yoctometer at the tight 10^-35 m scale.<br /><br />Geez louise, I thought Steven Colyerhttps://www.blogger.com/profile/10435759210177642257noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-56316640703029164902010-11-03T03:44:35.153-04:002010-11-03T03:44:35.153-04:00Very nicely put, Robert, to which I would add that...Very nicely put, Robert, to which I would add that as he aged, and possibly because of Grossman's influence, he got deeper into the Mathematics and farther from the concepts. That he produced less (the EPR paper being an exception) in his later years may or may not have been due to that shift, but there may be a cautionary tale there, nevertheless. <br /><br />As to your comment "almost Steven Colyerhttps://www.blogger.com/profile/10435759210177642257noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-89525596683283046782010-10-30T22:38:31.321-04:002010-10-30T22:38:31.321-04:00Phil et al,
When you study Einstein's work ca...Phil et al,<br /><br />When you study Einstein's work carefully, whether it's the photon theory of radiation, stimulated emission, general relativity, etc., you see that it is his gifts in conceptual thinking that led him to his discoveries, which were subsequently given mathematical expression.<br /><br />This is especially clear with general relativity. Almost completely isolated Robert L. Oldershawhttps://www.blogger.com/profile/15396555790655312393noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-88237166858214843562010-10-30T15:43:40.450-04:002010-10-30T15:43:40.450-04:00The best way to succeed in (American) politics is ...The best way to succeed in (American) politics is be be born to a Yale University Skull & Bones society member, be one yourself, or be willing to deal with them. I never will, because they stole Geronimo's skull, which greatly offends me. Free Leonard Peltier!Steven Colyerhttps://www.blogger.com/profile/10435759210177642257noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-39573067911013466562010-10-30T13:02:18.718-04:002010-10-30T13:02:18.718-04:00Hi Bee,
Unfortunately, the result is that politic...Hi Bee,<br /><br /><i>Unfortunately, the result is that politics tends to be dominated by people who have a liking in these games rather than those who actually have the insight.</i><br /><br />I think you’re being too kind to politicians, particularly as of late it appears the most successful being those that tell the people what they want to hear, rather than what they need to hear, and if Phil Warnellhttps://www.blogger.com/profile/15671311338712852659noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-3798361626012892402010-10-30T12:58:28.362-04:002010-10-30T12:58:28.362-04:00This comment has been removed by the author.Phil Warnellhttps://www.blogger.com/profile/15671311338712852659noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-29995274950595377552010-10-30T12:24:07.400-04:002010-10-30T12:24:07.400-04:00Hi Phil,
Yes, it's an interesting story. The ...Hi Phil,<br /><br />Yes, it's an interesting story. The persistence of his trying to find the place to fit in is quite remarkable. While one certainly shouldn't generalize one person's story, it is also interesting to note which fields he did not feel his intellect would be well used. Especially when it comes to politics it seems to me the most intelligent people shy away from it Sabine Hossenfelderhttps://www.blogger.com/profile/06151209308084588985noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-11673695653174556582010-10-30T11:33:27.153-04:002010-10-30T11:33:27.153-04:00Hi Steven,
I see. That's a different point th...Hi Steven,<br /><br />I see. That's a different point though. You can't make a universe out of a black hole in ordinary general relativity. There has to be some transition (quantum gravitational?!) that does not obey the standard laws and that subsequently leaves you with a new "baby" universe. Not knowing how that transition actually works, looking back in time doesn't helpSabine Hossenfelderhttps://www.blogger.com/profile/06151209308084588985noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-40938045323631026632010-10-30T11:05:16.709-04:002010-10-30T11:05:16.709-04:00Hi Robert,
First I would hope what I had to say a...Hi Robert,<br /><br />First I would hope what I had to say about Witten as not being taken as hero worship or zealot like admiration, beyond in him being one persistent enough in the pursuit to find what stands to be his purpose. That said, I would admit how Witten does serve to inspire me being resultantly that he demonstrates the potential which our species as a whole might one day rejoice in Phil Warnellhttps://www.blogger.com/profile/15671311338712852659noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-90414556649762445702010-10-30T11:01:38.291-04:002010-10-30T11:01:38.291-04:00This comment has been removed by the author.Phil Warnellhttps://www.blogger.com/profile/15671311338712852659noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-55236937865298249572010-10-30T09:35:04.999-04:002010-10-30T09:35:04.999-04:00For decades there has been virtual hero-worship of...For decades there has been virtual hero-worship of Witten within the theoretical physics community.<br /><br />There is no question about the fact that he is exceptionally knowledgeable and creative in analytical matters, especially the intersection of math and physics.<br /><br />However, I think one could argue that when it comes to a conceptual understanding of nature, he talents are, at best,Robert L. Oldershawhttps://www.blogger.com/profile/15396555790655312393noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-12711884915674121672010-10-30T09:17:23.769-04:002010-10-30T09:17:23.769-04:00Hi Bee,
Thanks, as I find this tale regarding Wit...Hi Bee,<br /><br />Thanks, as I find this tale regarding Witten being interesting, as I also draw the same conclusion regarding the nature and character of him as that of the author. However, what I think perhaps being the more important thing, which is easily missed as it only to be found buried between the lines, being for me it serves to have made more clear how people differ, as to what Phil Warnellhttps://www.blogger.com/profile/15671311338712852659noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-54563312591317394822010-10-30T07:07:17.317-04:002010-10-30T07:07:17.317-04:00Regarding the Scale of the Universe thing by Cary ...Regarding the <a href="http://htwins.net/scale/" rel="nofollow">Scale of the Universe thing by Cary and Michael Huang</a>, yup, that's pretty amazing and thank you for that, Bee and Stefan, but of course I have some comments on it:<br /><br />1) Preons? Preons?! Are those accepted now by mainstream Physics, or are they a mere speculative fantasy from the mind of John Archibald Wheeler? I'Steven Colyerhttps://www.blogger.com/profile/10435759210177642257noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-37004930175550706972010-10-30T07:03:16.202-04:002010-10-30T07:03:16.202-04:00This comment has been removed by the author.Steven Colyerhttps://www.blogger.com/profile/10435759210177642257noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-69832846937336453452010-10-29T13:10:46.575-04:002010-10-29T13:10:46.575-04:00Regarding the observation of a neutron star with a...Regarding the observation of a neutron star with a mass of about 2 solar masses, consider the following.<br /><br />My research leads me to the concluson that the upper limit mass for a "stellar-mass" black hole or neutron star (the former in a highly excited state) is about 30 solar masses.<br /><br />The most massive observed "stellar-mass" black hole has an estimated mass Robert L. Oldershawhttps://www.blogger.com/profile/15396555790655312393noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-51422528675474134982010-10-29T12:51:15.902-04:002010-10-29T12:51:15.902-04:00Hi Bee,
You wrote:
I've been wondering why th...Hi Bee,<br /><br />You wrote:<br /><i>I've been wondering why the idea didn't catch more fire. </i><br /><br />Me neither, but you must admit <a href="http://en.wikipedia.org/wiki/Fecund_universes" rel="nofollow">Fecund universe theory</a> is somewhat shocking the first time you hear of it. When I first read of it was adamantly against it, for example (what are you physicists smoking?!), Steven Colyerhttps://www.blogger.com/profile/10435759210177642257noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-22914222858196027432010-10-29T11:41:32.059-04:002010-10-29T11:41:32.059-04:00http://www.mazepath.com/uncleal/uncleal2.jpg
Uncle...http://www.mazepath.com/uncleal/uncleal2.jpg<br />Uncle Al likes cats. That was Xerxes.<br /><br />Mathematics has no empirical basis, by definition. Thus string theory, economics, SUSY, meteorology... Hey Ed, it's not a soufflé until it's served persistently inflated to resist a fork.<br /><br />Nature 467, 1081 (2010)<br /> Who wanted them to look?<br />Phys. Rep. 442, 109-165 (2007Uncle Alhttps://www.blogger.com/profile/05056804084187606211noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-47139226083444642152010-10-29T11:02:10.332-04:002010-10-29T11:02:10.332-04:00Well... I like the idea, baby universes and so on,...Well... I like the idea, baby universes and so on, cute ;-) (Also, cute puppy in your profile pic. Yours?) I'm not too convinced by the realization though. Mostly because I think the "number of black holes" is ill-defined. In any case, I've been wondering why the idea didn't catch more fire. After all, it's how old now? 15 years? 20? It seems to me possible there might Sabine Hossenfelderhttps://www.blogger.com/profile/06151209308084588985noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-58251241806853016662010-10-29T10:50:56.101-04:002010-10-29T10:50:56.101-04:00Hi Bee, Do you LIKE Lee Smolin's Cosmological ...Hi Bee, Do you LIKE Lee Smolin's Cosmological Natural Selection?<br /><br />I do, with zero proof that it's right, and I wrack my brain daily thinking about an experiment that would prove it one way or the other.<br /><br />Sean Carroll disagrees that a Universe can exist inside a black hole, which reminds me, yet again, how much physicists disagree with each other at the cutting edge Steven Colyerhttps://www.blogger.com/profile/10435759210177642257noreply@blogger.com