tag:blogger.com,1999:blog-22973357.comments2014-09-21T18:52:15.639-04:00BackreactionSabine Hossenfelderhttps://plus.google.com/111136225362929878171noreply@blogger.comBlogger36965125tag:blogger.com,1999:blog-22973357.post-33272945880202105672014-09-21T18:52:15.639-04:002014-09-21T18:52:15.639-04:00Great post. This article is really very informativ...Great post. This article is really very informative & effective. I think its must be helpful for us. <br /><b><a href="http://outsourcingpark.blogspot.com/p/social-bookmarking-sites-list.html" rel="nofollow">Social Bookmarking Sites List</a></b> | <b><a href="http://outsourcingpark.blogspot.com/p/free-directory-submission-list.html" rel="nofollow">Directory Submission List</a></b>Abdul Alimhttp://www.blogger.com/profile/02632405586238247731noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-74756408002970366852014-09-21T17:13:38.395-04:002014-09-21T17:13:38.395-04:00I did a new theory idea on minimum distance that i...I did a new theory idea on minimum distance that included many of the ideas of posters here considered- in the form of a poems, with reversals of all the current issues of art and science funding and so on. It is on my blog and face book notes.L. Edgar Ottohttp://www.blogger.com/profile/00525169618204198073noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-15181000271253766942014-09-20T13:37:01.146-04:002014-09-20T13:37:01.146-04:00Hush, I have enjoyed your Bob and Alice series of ...Hush, I have enjoyed your Bob and Alice series of post comments.<br /><br />In this general question of minimum distance, and of the distinction between things and notions. While drawing I said to my Artist roommate some decades back "It seems to me an artist tries to express things beginning with a minimum of lines to start with. " He said that was right. I was thinking where exactly I could color things between the lines as the borders to a keen eye can seem so fuzzy.<br />So for a question, one of the issue between the quality and quality, the continuous and discrete to consider would be this : As in the poetry with its concentration of meanings, Is there an analog to minimum distance in the sense of such notions of minimum dimensions as art? For unity of the possibility algebra of theory and thought are these strictly equivalent or only locally appear so or not as variations?"L. Edgar Ottohttp://www.blogger.com/profile/00525169618204198073noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-76138203946902244462014-09-19T12:16:15.778-04:002014-09-19T12:16:15.778-04:00Hi, Bee! congratulations, I was really looking for...Hi, Bee! congratulations, I was really looking for a long time an article that could offer different concepts of time in accordance with SR. <br /><br />Personally I agree with you in many respects. I yet not fully understand the math involved in the field, though, but I think that we - humans - definitely needs more clues in regard such topic.<br /><br />Personally I do not believe in a block universe as many physics out there profess, but I feel your picture of existence-slices and absolutes planes of existence very appealing. <br /><br />Please, go on!Andrea Spadahttp://www.blogger.com/profile/16821111912885905380noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-46582522943743201862014-09-19T08:25:15.629-04:002014-09-19T08:25:15.629-04:00Deliver your love and good wishes in the form of C...Deliver your love and good wishes in the form of Cakes to the doorsteps of your dear ones on perfect time through the wide network of online shopping store. <a href="http://www.cakedeliverychennai.com" rel="nofollow">Send Cakes to Chennai</a> and bring joy and happiness to the celebration.Sutapa Duttahttp://www.blogger.com/profile/06848971248781287175noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-78394726751487687742014-09-19T05:38:48.113-04:002014-09-19T05:38:48.113-04:00A. Mikovic:
Not correct. If you have any fixed ed...A. Mikovic:<br /><br />Not correct. If you have any fixed edge length it violates Lorentz-invariance and the constraints on this are much tighter, already well beyond the Planck scale. (Depends on the coupling in the effective limit.) Best,<br /><br />B.Sabine Hossenfelderhttp://www.blogger.com/profile/06151209308084588985noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-42660697930996993312014-09-19T04:34:20.602-04:002014-09-19T04:34:20.602-04:00If one assumes that the spacetime is a PL manifold...If one assumes that the spacetime is a PL manifold corresponding to a triangulation, then the metric is determined by the edge lengths. If the space is a compact 3d manifold,<br />then there will be a minimal edge length L. If the number of the 4-simplices is large, then one can approximate the effective quantum dynamics by the effective action for the QFT with a momentum cutoff<br />hbar/L corresponding to GR coupled to matter. Since the LHC experiments have not seen any QG effects, this means that <br /> l_P << L < 10^{-20}m.A. Mikovichttp://www.blogger.com/profile/03175906801121515444noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-462832784711171452014-09-18T20:53:09.131-04:002014-09-18T20:53:09.131-04:00DocG,
Ize roan speak English even as a minor poet ...DocG,<br />Ize roan speak English even as a minor poet we invent English.<br />You asked Sabine a damn good physics question (do we really want to know the answer? )<br />Thanks for the issue and inspiration. I made it the lead poem for my series in Facebook notes. SphereFarmer. I mean no disrespect. L. Edgar Ottohttp://www.blogger.com/profile/00525169618204198073noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-73610754103312639732014-09-18T18:04:58.647-04:002014-09-18T18:04:58.647-04:00Alice,
B.What if we wait?
A.Wait for what?
B.Wai...Alice,<br /><br />B.What if we wait?<br />A.Wait for what?<br /><br />B.Wait for the equation that finds<br />any prime.<br />A.What good will that do?<br /><br />B.That will give insight into the structure of numbers.<br /><br />A.This is a physics blog.<br />B.<br /><br />Q.Why didn't Bob answer Alice?<br />A.Bob decided to wait for insight into structure. Physical or not.<br /><br /><br />ARBBB,<br />Bob<br /><br />Text Key:<br /><br />B.= Bob<br />A.= Alice<br />Q.= Question<br />A.= Answer<br />ARBBB. =Avid Reader(Twin) of Bee's Blog/Backreactionhushhttp://www.blogger.com/profile/16176588791118304829noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-18184407682326760462014-09-18T17:48:07.414-04:002014-09-18T17:48:07.414-04:00I'll accept the simplest minimum length ... &...I'll accept the simplest minimum length ... "unable to resolve it beyond some limit "<br /><br />Here is my number <br />10^-18m<br />jalhttp://www.blogger.com/profile/16969819389823705458noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-34789632713426186642014-09-18T17:14:29.633-04:002014-09-18T17:14:29.633-04:00Mr. Otto.
Either you have some serious issues wit...Mr. Otto. <br />Either you have some serious issues with the English language or you are putting us on. I'm still waiting for Bee to respond to my question regarding Abramowicz's work.DocGhttp://www.blogger.com/profile/17359004200002936544noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-62833383757788251392014-09-18T15:17:24.199-04:002014-09-18T15:17:24.199-04:00If I ask - given the solar system, with the charac...If I ask - given the solar system, with the characteristic mass scale being that of the Sun or Jupiter, the characteristic length scale being that of a planetary orbit (a few A.U.), and Newton's constant - what is the characteristic time, based purely on dimensional analysis? <br /><br />The answer is, of course, that the characteristic times planetary orbital periods - i.e., of the order of years.<br /><br />But somehow the system also produces much longer time scales - of the order of 100s of millions of years for stability of the planetary system. (I believe the system is chaotic, but one can estimate a probability that two planets have collided, or a planet has been ejected.).<br /><br />e.g., Wiki <a href="http://en.wikipedia.org/wiki/Stability_of_the_Solar_System" rel="nofollow">http://en.wikipedia.org/wiki/Stability_of_the_Solar_System</a><br /><br />"Jacques Laskar and his colleague MickaĆ«l Gastineau in 2009 took a more thorough approach by directly simulating 2500 possible futures. Each of the 2500 cases has slightly different initial conditions: Mercury's position varies by about 1 metre between one simulation and the next. In 20 cases, Mercury goes into a dangerous orbit and often ends up colliding with Venus or plunging into the Sun. Moving in such a warped orbit, Mercury's gravity is more likely to shake other planets out of their settled paths: in one simulated case its perturbations send Mars heading towards Earth".<br /><br />So, e.g., one could define a characteristic time when there is a exp(-1) probability that the system has "decayed", and that time would be 100s of millions of orbital periods.<br /> <br /><br />* Can dynamical systems produce even larger ratios? I think so - think of nuclear reaction times compared with radioactive nuclei decay times.<br /><br />* Is there some way to produce such large ratios of time scales via purely dimensional analysis? <br /><br /><br /><br />Arunhttp://www.blogger.com/profile/03451666670728177970noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-70530532659240111472014-09-18T10:03:19.854-04:002014-09-18T10:03:19.854-04:00The talks were not recorded, so it seems unlikely....The talks were not recorded, so it seems unlikely...Sabine Hossenfelderhttp://www.blogger.com/profile/06151209308084588985noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-51451511340835367392014-09-18T08:05:40.627-04:002014-09-18T08:05:40.627-04:00Bee, are the videos of the conference online (simi...Bee, are the videos of the conference online (similar to the one at Perimeter institute)?<br />Shantanuhttp://www.blogger.com/profile/16322812456382858228noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-91314410180637808592014-09-17T17:14:03.201-04:002014-09-17T17:14:03.201-04:00DocG
I notice he has very recent papers on these i...DocG<br />I notice he has very recent papers on these issues. So why did you offer such a primitive paper? The symmetry looks like that preserved Lorentz as hyperbolic. The idea of rotating gyroscopes does not address deeper issues of chirality whenever that paper was offered.L. Edgar Ottohttp://www.blogger.com/profile/00525169618204198073noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-24450132023420730072014-09-17T16:47:22.168-04:002014-09-17T16:47:22.168-04:00DocG
I wonder what he would make of these ideas if...DocG<br />I wonder what he would make of these ideas if Abramowicz applied them to this interesting new observation?<br /><br />http://spacetelescope.org/news/heic1419/<br /><br />"Additionally, the results could affect theories of how such UCDs form. "This finding suggests that dwarf galaxies may actually be the stripped remnants of larger galaxies that were torn apart during collisions with other galaxies, rather than small islands of stars born in isolation," explains Seth. "We don't know of any other way you could make a black hole so big in an object this small."<br /><br />Lorentz and Einstein holds when taking into this century. More than that we do not have the vague answers and worries if the universe falls apart by some experiment or shift of a vacuum. And in a unified theory where quantum holds as well. Still, we can see that the electrical part of that unity as Einstein's first vague vision transcends issues of local and non-local as if some intrinsic curved or flat surface was the better description of a deeper relativity... all concerns he pondered these entities charged or not.<br />Now if A senses a top down or bottom up flow of things both the case does his theory apply to scale? The grid of tensors is a unity but it is also an infinite span as in quantum matrices. Our vague dreams do have explanations that they escape from the depths and are not always what we see as the same size clumps of space and matter.<br />Would the twin paradox hold in some case where we limit matrices as solutions of the physical?<br /><br />L. Edgar Ottohttp://www.blogger.com/profile/00525169618204198073noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-50307605869194237822014-09-17T13:41:57.845-04:002014-09-17T13:41:57.845-04:00Thanks Mr. Otto, but your response is extremely va...Thanks Mr. Otto, but your response is extremely vague and fanciful -- compared with the work of Abramowicz, which is very specific and solidly based on both observation and logic. It looks to me as though Abramowicz has achieved an important conceptual breakthrough -- comparable in some ways to that of Einstein in formulating GR. And I'm wondering why there appears to have been no followup to his work in all these years.<br /><br />Are you familiar with his work, Bee? And if so can you provide a reason why it's apparently been ignored? DocGhttp://www.blogger.com/profile/17359004200002936544noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-67252182190884541622014-09-16T19:03:59.438-04:002014-09-16T19:03:59.438-04:00DocG
The universe itself as a physical totality c...DocG<br /> The universe itself as a physical totality can be so conceived.<br /> All things vibrate some day but bounded by what?<br /> Such an external principle may actually exist as a metaphysical mirror, say light speed negative and as with time reversed.<br />So, can we imagine exceeding cardinality and ordinality, complex spaces aside and zero to open ended arrow of time.<br />Even with recursive fractal-like scale we could imagine different kinds of fundamental strings and develop new laws of interactions between them as well as condensates a step above Fermi and pair production and that above any unity of a dimensionless place of synced cycles of beginnings that may decohere randomly in development, even return in sync.<br />Mass and gravity as if external to each other, both involving at least five fold symmetry do seem inertia can approach something near singularity as if concrete and independently self contained. The standard model and deep gravity in this conceptual relation as such mirrors. Physics for now is the lesser physics and needed study of that in between to which we can debate and legitimately ask where does the information go?<br />In short it is a brilliant but very incomplete idea. L. Edgar Ottohttp://www.blogger.com/profile/00525169618204198073noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-84522208678872036642014-09-16T16:30:09.442-04:002014-09-16T16:30:09.442-04:00Has anyone ever considered that, as one approaches...Has anyone ever considered that, as one approaches the smallest length (presumably the Planck length), space might turn inside out? And that all those superparticles might be hiding in that inside out space?<br /><br />Marek Abramowicz's research on black holes suggests such a possibility. See for example his paper on the "Relativity of Inwards and Outwards"<br /><br /> http://articles.adsabs.harvard.edu/cgi-bin/nph-iarticle_query?1992MNRAS.256..710A&data_type=PDF_HIGH&whole_paper=YES&type=PRINTER&filetype=.pdfDocGhttp://www.blogger.com/profile/17359004200002936544noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-11596277713537963642014-09-16T15:21:08.106-04:002014-09-16T15:21:08.106-04:00If phase space is "quantized" - as in ha...If phase space is "quantized" - as in has a minimum volume, where it doesn't make sense to talk of smaller volumes -- and one of spatial length, area or volume is also "quantized", then so must momentum, and vice versa? Arunhttp://www.blogger.com/profile/03451666670728177970noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-54050251039869730222014-09-16T06:39:18.801-04:002014-09-16T06:39:18.801-04:00Thanks for the reply Bee. Your interpretation is t...Thanks for the reply Bee. Your interpretation is the one I can understand :)<br /><br />Cheers,<br />NirmalyaNirmalyahttp://www.blogger.com/profile/00482736027241310182noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-28374036535824330782014-09-16T04:50:58.082-04:002014-09-16T04:50:58.082-04:00Nirmalya:
Well, if you want a modification for a ...Nirmalya:<br /><br />Well, if you want a modification for a free particle then gravity is weak (for all particles we know), so (global) Lorentz-invariance is what you expect when you change coordinate frames. Now why you would expect there to be any effect for that particle if gravity is weak is a different question and I'm the wrong person to ask. The argument that I normally get to hear is that it's supposedly a deformation of the symmetry of the space-time ground state. <br /><br />In the rather boring interpretation that I favor, the Lorentz-invariance is that of the asymptotically flat space. You have in/outgoing particles with momenta, the cross-sections are computed from these (and some quantum numbers etc). You have Lorentz-invariance of the resulting observables in the standard sense under transformations acting on these in/outgoing states. <br /><br />Now what you can do is that you construct a local momentum that you trace through the interaction region and this momentum then will no longer transform under the normal Lorentz-transformation because the space-time is curved (as you expect). In <a href="http://arxiv.org/abs/1008.3345" rel="nofollow">this paper with Xavier and Roberto</a> we argued that in Asymptotically Save Gravity space-time becomes effectively energy-dependent (depending on the energy of the collision in this case) and then the momentum and its transformation is 'deformed' in the collision region - which is where you expect strong gravity, in particular it has an upper bound and cross-sections stagnate once you reach that limit, they become asymptotically constant. <br /><br />I don't like to refer to this as a smallest length exactly because of the reason you mention. I normally refer to it as a limit on the 'resolution of structures', which means that com energies beyond the Planck energy cannot deliver any new information, in the above explained meaning that cross-sections run towards some limiting value and then just stay there. Best,<br /><br />B.Sabine Hossenfelderhttp://www.blogger.com/profile/06151209308084588985noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-16049308907518082532014-09-15T17:11:34.211-04:002014-09-15T17:11:34.211-04:00Andrii,
One bit is not enough to clarify things as...Andrii,<br />One bit is not enough to clarify things as it can be fuzzy in between or 1 or 0 to show there must be a minimum length or duration as these can represent a line or point in the context of a more general space. As we can add more groups of bits, this paradox still remains for each unitary bit.L. Edgar Ottohttp://www.blogger.com/profile/00525169618204198073noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-21206734428296703112014-09-15T16:50:17.010-04:002014-09-15T16:50:17.010-04:00Kneemo, between the holophrasic and the staccato (...Kneemo, between the holophrasic and the staccato (old linguistic terms) or the holographic and fractal emergent views, quasi-contiguity both incorporating these symmetry concepts or not - your great question occurred to me too. Minimum distance grounded when the Planck context is higher volume.L. Edgar Ottohttp://www.blogger.com/profile/00525169618204198073noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-56885357411278774792014-09-15T15:57:57.256-04:002014-09-15T15:57:57.256-04:00Hi Bee
There's one more thing that confuses m...Hi Bee<br /><br />There's one more thing that confuses me - when one speaks of the possible tension between an invariant minimal length and Lorentz transformations, is one speaking in the context of a. flat space field theory? That would seem odd, because we've chosen to neglect gravity there in the first place. If gravity became important global Lorentz symmetry would be lost anyway. or b. Lorentz invariance in a small co-ordinate patch ? I suppose I'm asking about the regime of validity of theories which incorporate an invariant Planck length in a flat space field theory framework.<br />Cheers,<br />Nirmalya<br />Nirmalyahttp://www.blogger.com/profile/00482736027241310182noreply@blogger.com