tag:blogger.com,1999:blog-5880610.post2303128004658242266..comments2021-06-11T14:13:26.703-04:00Comments on Information Processing: Backreaction, black holes and monstersSteve Hsuhttp://www.blogger.com/profile/02428333897272913660noreply@blogger.comBlogger22125tag:blogger.com,1999:blog-5880610.post-84716744367437555592009-01-17T13:01:00.000-05:002009-01-17T13:01:00.000-05:00The construction has more to do with the internal ...The construction has more to do with the internal logical consistency of models of quantum gravity than with any realistic phenomena.Steve Hsuhttps://www.blogger.com/profile/02428333897272913660noreply@blogger.comtag:blogger.com,1999:blog-5880610.post-8099402281007734882009-01-17T12:54:00.000-05:002009-01-17T12:54:00.000-05:00gs said...But a (hypothetical) monster wouldn't ha...<I>gs said...But a (hypothetical) monster wouldn't have distinctive astronomical signatures?<BR/><BR/><B>Steve Hsu</B> said...From the outside a black hole resulting from the collapse of a monster looks just like any other black hole. There might be some implications for the endpoint of black hole evaporation...</I><BR/><BR/>In my untutored opinion, it would be noteworthy if a monster's gshttps://www.blogger.com/profile/17953008291916883288noreply@blogger.comtag:blogger.com,1999:blog-5880610.post-86994903649989933562009-01-16T22:14:00.000-05:002009-01-16T22:14:00.000-05:00In Jonathan's construction he builds the object ou...In Jonathan's construction he builds the object out of thin shells and assumes equilibrium. We do not assume equilibrium -- we simply want to count the number of distinct initial data with fixed ADM mass. This number can be larger than exp(A). Yet, each of the distinct configurations will collapse to a black hole with area A.Steve Hsuhttps://www.blogger.com/profile/02428333897272913660noreply@blogger.comtag:blogger.com,1999:blog-5880610.post-89553255479819630432009-01-16T22:13:00.000-05:002009-01-16T22:13:00.000-05:00PS: Also see subsequent papers by Oppenheim (on ar...PS: Also see subsequent papers by Oppenheim (on arXiv.org) concerning thermodynamics in the presence of long-range interactions, all of which touch on the similarity of this situation to gravitating systems.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-5880610.post-78568878240793925252009-01-16T22:00:00.000-05:002009-01-16T22:00:00.000-05:00Probably incidental, but see this paper by Jonatha...Probably incidental, but see this paper by Jonathan Oppenheim (2001):<BR/><BR/><A HREF="http://arxiv.org/abs/gr-qc/0105101" REL="nofollow">Area scaling entropies for gravitating systems</A> (gr-qc/0105101)Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-5880610.post-89523265018468083632009-01-16T19:15:00.000-05:002009-01-16T19:15:00.000-05:00Perfectly summarized!Perfectly summarized!Steve Hsuhttps://www.blogger.com/profile/02428333897272913660noreply@blogger.comtag:blogger.com,1999:blog-5880610.post-64975456931860577172009-01-16T19:07:00.000-05:002009-01-16T19:07:00.000-05:00I think I understand. You've created a semiclassi...I think I understand. You've created a semiclassical object on a compact domain, whose entropy exceeds the maximum possible cardinality of a quantum state on that domain. Hence, it cannot exist if you believe the string theory interpretation of black hole entropy.Carson C. Chowhttps://www.blogger.com/profile/08464737817585277975noreply@blogger.comtag:blogger.com,1999:blog-5880610.post-1454900005532149142009-01-16T18:21:00.000-05:002009-01-16T18:21:00.000-05:00It can't be in the Hilbert space because the dimen...It can't be in the Hilbert space because the dimensionality of the Hilbert space (entropy) is bounded above for a compact object of some fixed mass M. In other words, if I give you an energy budget of M and a compact region of space then there are only supposed to be of order exp(M^2) possible distinct quantum states. This comes from so-called black hole entropy bounds: we imagine smashing your Steve Hsuhttps://www.blogger.com/profile/02428333897272913660noreply@blogger.comtag:blogger.com,1999:blog-5880610.post-64694422961890643212009-01-16T17:40:00.000-05:002009-01-16T17:40:00.000-05:00Interesting. Is the implication that it is not in ...Interesting. Is the implication that it is not in Hilbert space or rather that there are other constraints that rule it out?<BR/><BR/>For example, not being in Hilbert space doesn't rule out weak solutions. The delta functional is not in L2 after all but it is a useful solution.Carson C. Chowhttps://www.blogger.com/profile/08464737817585277975noreply@blogger.comtag:blogger.com,1999:blog-5880610.post-71875779195531564772009-01-16T17:08:00.000-05:002009-01-16T17:08:00.000-05:00I just made that up. From the perspective of the s...I just made that up. From the perspective of the string theorists and AdS/CFT duality believers these configurations are monstrous -- they have to be excised from the Hilbert space or else they would contradict that camp's interpretation of black hole entropy and much more. <BR/><BR/>The interesting implication of monsters is that here you have a perfectly good semiclassical configuration in Steve Hsuhttps://www.blogger.com/profile/02428333897272913660noreply@blogger.comtag:blogger.com,1999:blog-5880610.post-75038505852004121742009-01-16T16:58:00.000-05:002009-01-16T16:58:00.000-05:00Hi Steve,Stupid question - Why is this solution ca...Hi Steve,<BR/><BR/>Stupid question - Why is this solution called a monster?Carson C. Chowhttps://www.blogger.com/profile/08464737817585277975noreply@blogger.comtag:blogger.com,1999:blog-5880610.post-80996483592333297412009-01-16T09:56:00.000-05:002009-01-16T09:56:00.000-05:00I forgot whether we mention the covariant (Bousso)...I forgot whether we mention the covariant (Bousso) entropy bound in the paper, but at least when I give the talk I tend to mention that it is not violated. (IIRC, if you follow one of his lightsheets into the monster it only intercepts a finite amount of entropy before focusing to a point.) <BR/><BR/>But that is distinct from the question of whether all of the information in the interior monster Steve Hsuhttps://www.blogger.com/profile/02428333897272913660noreply@blogger.comtag:blogger.com,1999:blog-5880610.post-45660921363158517382009-01-16T07:31:00.000-05:002009-01-16T07:31:00.000-05:00Hi Steve,Why didn't you mention Bousso's bound, in...Hi Steve,<BR/><BR/>Why didn't you mention Bousso's bound, instead of just of Bekenstein's, in your article? Since you are very interested in intense gravitational fields, that one is the most general and successful formulation of a gravitational entropy bound that I am aware of. Unless, someone else find a bad fauld in his bound or something better.Daniel de França MTd2https://www.blogger.com/profile/01281817409696805377noreply@blogger.comtag:blogger.com,1999:blog-5880610.post-54588598604757093172009-01-15T22:52:00.000-05:002009-01-15T22:52:00.000-05:00From the outside a black hole resulting from the c...From the outside a black hole resulting from the collapse of a monster looks just like any other black hole. There might be some implications for the endpoint of black hole evaporation, but that depends on some aspects of quantum gravity which we do not yet understand.Steve Hsuhttps://www.blogger.com/profile/02428333897272913660noreply@blogger.comtag:blogger.com,1999:blog-5880610.post-49757598586364104892009-01-15T22:05:00.000-05:002009-01-15T22:05:00.000-05:00But a (hypothetical) monster wouldn't have distinc...But a (hypothetical) monster wouldn't have distinctive astronomical signatures?gshttps://www.blogger.com/profile/17953008291916883288noreply@blogger.comtag:blogger.com,1999:blog-5880610.post-25929909587957414782009-01-15T21:56:00.000-05:002009-01-15T21:56:00.000-05:00If such objects exist it would be possible to fall...If such objects exist it would be possible to fall into a black hole and discover a much richer variety of interiors than would be thought by "entropy counts the micro-states" camp.Steve Hsuhttps://www.blogger.com/profile/02428333897272913660noreply@blogger.comtag:blogger.com,1999:blog-5880610.post-17148559943241869772009-01-15T21:49:00.000-05:002009-01-15T21:49:00.000-05:00Naive question: if a monster exists, how, if at a...Naive question: if a monster exists, how, if at all, might its presence be inferred by present or future instruments?gshttps://www.blogger.com/profile/17953008291916883288noreply@blogger.comtag:blogger.com,1999:blog-5880610.post-80629961300997629242009-01-15T16:43:00.000-05:002009-01-15T16:43:00.000-05:00Another example of the great utility of modern phy...Another example of the great utility of modern physics.<BR/><BR/>Or rather, the great fraud?Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-5880610.post-22071171600931015262009-01-15T15:39:00.000-05:002009-01-15T15:39:00.000-05:00Re: cookie monster, neither could I!Re: cookie monster, neither could I!Steve Hsuhttps://www.blogger.com/profile/02428333897272913660noreply@blogger.comtag:blogger.com,1999:blog-5880610.post-72493649070393542522009-01-15T15:34:00.001-05:002009-01-15T15:34:00.001-05:00Hi Steve,Thanks for the link and sorry about the c...Hi Steve,<BR/><BR/>Thanks for the link and sorry about the cookie-monster picture, couldn't resist :-) Best,<BR/><BR/>B.Sabine Hossenfelderhttps://www.blogger.com/profile/06151209308084588985noreply@blogger.comtag:blogger.com,1999:blog-5880610.post-8654023796015882402009-01-15T15:34:00.000-05:002009-01-15T15:34:00.000-05:00Anonymous: What I said de facto about Klein's book...Anonymous: What I said de facto about Klein's book was a) I am reading it, though not finished b) I am skeptic about it because it presents a very single-sided point of view c) it is a useful source of data. Check for yourself what I wrote if you doubt it. Besides this, I am very sure you don't have any data on my IQ, supposedly or non-supposedly. Best.<BR/><BR/>B.Sabine Hossenfelderhttps://www.blogger.com/profile/06151209308084588985noreply@blogger.comtag:blogger.com,1999:blog-5880610.post-21220725901093688542009-01-15T14:33:00.000-05:002009-01-15T14:33:00.000-05:00Supposedly a high-IQ theoretical physicist, yet sp...Supposedly a high-IQ theoretical physicist, yet speaks positively about Klein's "The Shock Doctrine".Anonymousnoreply@blogger.com