tag:blogger.com,1999:blog-7315236707728759521.post7927151308159750696..comments2024-03-28T19:02:22.210-06:00Comments on Dispatches From Turtle Island: Confirmation of SM Character Of Higgs ContinuesAndrew Oh-Willekehttp://www.blogger.com/profile/02537151821869153861noreply@blogger.comBlogger12125tag:blogger.com,1999:blog-7315236707728759521.post-77357488377985728212013-12-10T15:17:38.471-07:002013-12-10T15:17:38.471-07:00More discussion of Higgs property impacts on SUSY ...More discussion of Higgs property impacts on SUSY is found <a href="http://arxiv.org/pdf/1308.0297v2.pdf" rel="nofollow">here.</a>andrewhttps://www.blogger.com/profile/08172964121659914379noreply@blogger.comtag:blogger.com,1999:blog-7315236707728759521.post-10093572785868440462013-12-10T14:43:34.664-07:002013-12-10T14:43:34.664-07:00The literature of SUSY Higgs boson constraints is ...The literature of SUSY Higgs boson constraints is summarized <a href="http://pdg8.lbl.gov/rpp2013v2/pdgLive/DataBlock.action?node=S055HSS" rel="nofollow">here</a> and <a href="javascript:void(0);" rel="nofollow">here</a>.andrewhttps://www.blogger.com/profile/08172964121659914379noreply@blogger.comtag:blogger.com,1999:blog-7315236707728759521.post-51447920507034555142013-12-10T14:31:43.666-07:002013-12-10T14:31:43.666-07:00"exactly what are the conditions required to ..."exactly what are the conditions required to have it look like pure SM? The answer seems to be, high-scale SUSY breaking, and, some further condition in the Higgs sector."<br /><br />You need a bunch of parameters to have particular values that leave a pretty small corner of parameter space. Trickiest is that it is hard in more minimal or constrained versions of SUSY to get just one light Higgs and four heavy non-SM Higgs. You really need to have at least one be quite light. And, we haven't seen it. But, since we don't know precisely how it would act, it is hard to know what we are missing.<br /><br />One solution is that both light Higgs bosons in SUSY have degenerate (i.e. almost identical) masses. For example, this would make sense if the current data favoring a scalar SM Higgs boson over a pseudo-scalar Higgs boson never resolved its current 2-1 bias in favor of the SM result as precision in the measurement improved which would suggest the presence of a SM-like Higgs boson and a pseudoscalar-SUSY extra neutral Higgs boson A of identical mass and couplings in 2-1 proportions to each other.<br /><br />The exclusions of non-SM Higgs bosons at other masses so far seem entirely too timid to me. There just aren't any other bumps up to 600 GeV in the data and there should be at least one if there is a non-SM Higgs boson in that mass range and any reasonably constrained SUSY theory demands one somewhere under 1 TeV.andrewhttps://www.blogger.com/profile/08172964121659914379noreply@blogger.comtag:blogger.com,1999:blog-7315236707728759521.post-16835570528290247992013-12-10T14:24:10.615-07:002013-12-10T14:24:10.615-07:00Quantum entanglement is a mystery that requires on...Quantum entanglement is a mystery that requires one of three things to be violated, only two of which I can recall at the moment: locality, causality, or something else.<br /><br />A wormhole is a resolution of this effect that chooses non-locality to resolve the paradox using a curved space-time singularity approach to do so. It is not the only solution and there is really no way to show that this rather than some other mechanism is at work.<br /><br />There is really no experimental signature for this method of creating quantum entanglement versus any other, so it won't be validated or invalidated at the LHC.andrewhttps://www.blogger.com/profile/08172964121659914379noreply@blogger.comtag:blogger.com,1999:blog-7315236707728759521.post-76188455774075354302013-12-09T11:45:19.914-07:002013-12-09T11:45:19.914-07:00Sick today. Will comment someday.Sick today. Will comment someday.andrewhttps://www.blogger.com/profile/08172964121659914379noreply@blogger.comtag:blogger.com,1999:blog-7315236707728759521.post-56535743610707530892013-12-08T16:12:03.544-07:002013-12-08T16:12:03.544-07:00But particle entanglement does exist, and has been...But particle entanglement does exist, and has been demonstrated with all kind of particles. <br /><br />"This aspect would lead to new predictions, only if the wormhole description allowed you to calculate something more easily than the entanglement description"...<br /><br />They are saying that the wormholes create gravity. I know that gravity is hard to measure at this scale but there must be something to measure, right? An non-entangled quark (or whatever other particle) should be different than an entangled one IF this theory holds true. <br /><br />I wonder whether it'd be easier to observe if we could find quantum entanglement at the level of black holes. Maybe the patient astronomy can do what particle accelerators cannot?<br />Majuhttps://www.blogger.com/profile/12369840391933337204noreply@blogger.comtag:blogger.com,1999:blog-7315236707728759521.post-33320120992033561752013-12-08T14:05:41.383-07:002013-12-08T14:05:41.383-07:00"Beyond the theoretical debate about dS vs Ad..."Beyond the theoretical debate about dS vs AdS, there is real stuff being predicted here that can be tested."<br /><br />No, there is not. You are being misled by the reference to "quarks". Those are not the quarks of the real world; they are the fermions appearing on one side of the mathematical mapping. The quarks of the real world come in six "flavors", they have particular charges and mappings, they interact according to SU(3) gluons. The "quarks" of this CFT, like the quarks of the real world, would be spin 1/2 particles interacting via a gauge field, but that's about the extent of the commonality. The CFT here is a highly supersymmetric theory with particles and properties that are not part of reality (all the quarks are massless, for example). <br /><br />For now this is just mathematics, some generalization of which may eventually be relevant to reality. Even then, the wormholes might be untestable in some sense. Remember that they provide an equivalent description of the physics. There would be no new particle behavior, just a mathematical proof that the same old behavior also corresponded to a description in term of wormholes. This aspect would lead to new predictions, only if the wormhole description allowed you to calculate something more easily than the entanglement description; this is how AdS/CFT *did* lead to some predictions (with mixed results), when it was applied as an approximation scheme to quark-gluon plasma. And even then, it wasn't being used as an exact model of the world, AdS/CFT was instead providing a calculable model system whose thermodynamics were believed to be similar to those of the real quark-gluon plasma. Mitchellhttps://www.blogger.com/profile/10768655514143252049noreply@blogger.comtag:blogger.com,1999:blog-7315236707728759521.post-14772665616030417922013-12-08T05:48:34.754-07:002013-12-08T05:48:34.754-07:00I see, Mitchell: you feel it's merely theoreti...I see, Mitchell: you feel it's merely theoretical and may well be overridden soon, right? <br /><br />However I feel that the quark entanglement (with gravitational wormhole) prediction can be tested empirically in Geneva, right? That's what particle accelerators are for. Beyond the theoretical debate about dS vs AdS, there is real stuff being predicted here that can be tested.<br /><br />It may not be confirmed but what if it is?Majuhttps://www.blogger.com/profile/12369840391933337204noreply@blogger.comtag:blogger.com,1999:blog-7315236707728759521.post-22414821838394926152013-12-07T21:34:47.440-07:002013-12-07T21:34:47.440-07:00I can comment... That relationship is not yet bein...I can comment... That relationship is not yet being demonstrated for an empirically relevant theory like the standard model. There are numerous mathematical field theories, which are believed to be equivalent to string theories on a particular geometric background; this is the AdS/CFT duality. The cited papers are exhibiting detailed constructions that realize the Maldacena-Susskind idea, in the sense that pairs of entangled particles in the CFT, correspond to wormholes in the AdS geometry. <br /><br />I think it's fundamental stuff, but the real world is not AdS geometry (it's more like dS, de Sitter space), and we don't know how holography works for dS. So in a sense this is all still math, not physics. Mitchellhttps://www.blogger.com/profile/10768655514143252049noreply@blogger.comtag:blogger.com,1999:blog-7315236707728759521.post-52120702356516586992013-12-07T20:55:36.431-07:002013-12-07T20:55:36.431-07:00Erratum: I don't mean "salvaging" bu...Erratum: I don't mean "salvaging" but "saving" or "keeping". Majuhttps://www.blogger.com/profile/12369840391933337204noreply@blogger.comtag:blogger.com,1999:blog-7315236707728759521.post-20623602312386546052013-12-07T20:54:50.285-07:002013-12-07T20:54:50.285-07:00Andrew: have you read this?:
http://www.scienceda...Andrew: have you read this?:<br /><br />http://www.sciencedaily.com/releases/2013/12/131205142218.htm<br /><br />Superstrings Model strikes back by the hand of Maldacena and others: entanglement, at the level of black holes and fundamental particles alike, creates wormholes (always)... and also gravity, dumping Einstein but salvaging the Standard Model. <br /><br />What does Mr. Quark think of this? ;-)<br /><br />Majuhttps://www.blogger.com/profile/12369840391933337204noreply@blogger.comtag:blogger.com,1999:blog-7315236707728759521.post-15562591718679773262013-12-07T18:46:17.508-07:002013-12-07T18:46:17.508-07:00Concerning the future of SUSY models, I have two i...Concerning the future of SUSY models, I have two issues, one standard, one just a gap in my own knowledge. <br /><br />The standard issue is just naturalness. The point of weak-scale supersymmetry was to have a theory in which the electroweak scale is stable against quantum corrections due to heavy virtual particles, without finetuning of parameters. One can move the supersymmetry-breaking scale higher, but then finetuning is apparently necessary, removing one of the rationales for supersymmetry. <br /><br />I know you know this, I'm just stating it as context for the second issue. <br /><br />So here's the second issue. In general, the MSSM particle spectrum consists of the SM particle spectrum, plus superpartners; so if the superpartners all become sufficiently heavy, physics can look like pure SM up to quite high energies. <br /><br />The exception to this is the Higgs boson. In the SM, it's the same Higgs doublet which couples to all the fermions. In the MSSM, there are *two* Higgs superfields, one for an up-type Higgs that couples to up-type quarks, the other for a down-type Higgs that couples to down-type quarks and to charged leptons. This is required both by constraints on the allowed terms and by anomaly cancellation; the details can be found e.g. in Stephen Martin's MSSM primer. <br /><br />It might seem, therefore, that even if we assumed high-scale supersymmetry for the MSSM, we wouldn't get a single Higgs boson with SM-like couplings, because different Higgs fields are coupling to different fermions. Indeed, you get the 8-3=5 Higgs bosons left over, and it seems like their pattern of interactions and decays might be quite different from what we're seeing at LHC. <br /><br />Now I think it surely *could* be different, but I'm also pretty sure (because I've seen it in the literature) that there's a region of MSSM Higgs parameter space which really *does* look like a single SM Higgs boson with SM couplings. But what I don't know, is what the MSSM Higgs parameters have to be like, to produce such an SM imitation. <br /><br />Nor do I know how contrived that outcome is. Having all the superpartners heavy actually *is* fairly natural, it just requires that the main parameter controlling supersymmetry breaking falls in the right range. But I'm not aware of whether an SM-imitating Higgs sector in MSSM requires special tuning, or whether it can be achieved by a single condition (e.g. by having the mu parameter large?). <br /><br />This is relevant for understanding the remaining prospects for SUSY - exactly what are the conditions required to have it look like pure SM? The answer seems to be, high-scale SUSY breaking, and, some further condition in the Higgs sector. Mitchellhttps://www.blogger.com/profile/10768655514143252049noreply@blogger.com