Hi Willard,

Another good question. Actually Euro and Ansoldi's paper has some of the same features as our paper as well as an important difference which I will try to touch on. First if one looks at figure 1 of Euro's paper this is exactly the same point I was making about the UV/IR correspondence in my earlier reply. The hyperbola in the figure is the usual inverse relationship between energy/mass and length i.e. length ~ (energy/mass)^{-1}. The straight line curve is the gravity/BH relationship where length (horizon radius) goes linearly the mass/energy. The point where the curves intersect is the Planck mass/energy. Thus at energy scales higher than this scale one does not probe shorter distances any more but only makes a BH with ever larger horizon.

Now the series we propose based on self-similarity should apply to an evaporating black hole. The higher terms in the series represent higher energy of quantum fluctuations and are not directly tied to the mass of the black hole (actually there is the following connection: in the standard picture of BH evaporation as the black hole mass decreases the quantum fluctuations become larger/more important). Thus our series should apply to the case of an evaporating BH since the higher terms in the series represent higher energy quantum fluctuations not (directly) greater or smaller mass of the black hole.

Now in Euro's paper mentioned above and also in Euro's work with Piero they introduce a new feature that we do not have and this is where the difference arises. Euro and Piero have been working with non-commutative (NC) geometry - the idea that there is a non-trivial commutator between coordinates like x and y or x and z in the same way that in standard QM there is a non-trivial commutator between x and p. This NC geometry has the effect of introducing a minimal length scale into the theory (this is the theta parameter in Euro's paper). This has the very interesting feature that the IR/UV connection I mentioned is altered. This can be seen in figure 2 of Euro and Ansoldi's paper - they find that there is some minimal mass for a black hole. Lower than this mass one has a particle like lump or "remnant". Also in Euro's work with Piero they find that as the BH evaporates the temperature starts to decreases at some point and then goes to zero even when the object has a finite mass. They call this the "scram" phase since the black hole has been turned off in a manner similar to which nuclear power plants are shut down. Thus because of the NC geometry they work with the end stage of BH evaporation is different from ours where we would have the BH completely evaporate away. This was the reason we put "a conservative solution to the information paradox" since we do not assume any UV completion or cut-off or new UV physics. And let me say this is probably a negative feature for us since probably there is some new UV physics (a la NC geometry, string theory, loop QG) that comes into play. In fact I used Euro and Piero's "scram" mechanism is another recent work of mine on a new mechanism for inflation.

So which do I "believe" - that there is some new UV physics or that something like the "conservative" approach we use in our essay is correct? Well no one really has a good idea of what goes on at the Planck scale so the best thing is to look at different options and hope/see if there are some low energy observations one can make which would indicate experimentally which path is right. Also as it turns out there is still one free parameter in our essay, alpha_1, the first quantum correction coefficient which we cannot/do not fix. Taking alpha_1 as a free parameter leads to the possibility, even in our case, of having a remnant as in the case of Euro and Piero (although our mechanism for having a remnant is different than theirs).

Again a long reply so feel free to ask for clarifications or additional questions/comments.

Best,

Doug

Hi Doug,

Thanks for your helpful comments. I think my understanding of the Spallucci/Ansoldi paper is somewhat different than yours. It seems to me that their Figure 1 is meant to show that the Planck length is a minimal length that provides a UV cutoff: see p.3 of their paper, near equation 1. This cutoff means that increasing the energy of our probes beyond the Planck energy does not reveal anything new, i.e. it does not take us further and further into the UV, since the deep-UV is shielded from us by the event horizon of a Planck-scale black hole (this "shielding" is mentioned just above Fig. 1). As a result, we cannot obtain (trans-Planckian) higher-order corrections to the action by continuing to increase the energy of our probes; and so, it would seem, the self-similarity you describe gets broken at the Planck scale, at least on Spallucci & Ansoldi's account (and even apart from NC gemoetry).

Of course, as you say, self-similarity can still be preserved by eschewing a UV cutoff altogether; but the (not implausible) possibility that quantum fluctuations get more and more unpredictable and out of control as we move deeper into the UV creates some doubts about such self-similarity. Nonetheless, as you also note, if your model can be connected with low-energy observations and supported by experimental results, then those doubts can be erased. So, I guess we'll just have to wait on experimental and observational progress in order to figure out what's really going on at the Planck scale.

Good luck, and best wishes,

Willard

Doug et al,

Every time I hear that string theory is background dependent, I want to reach for my gun. :-) I think that even by Lee Smolin's criteria -- and *especially* applying the principle of self-similarity that you have so elegantly incorporated into your thesis, string theory forms a complete quantum field of spacetime that is self organizing and self annihilating.

I agree with Lawrence that your essay's position in the ratings does not at all reflect the quality of the work. I hope my high score to come will help.

And I hope you find interesting my own essay that agrees with your conjecture of infinitely self similar curves. Of course, I'm sure you've seen Professor Corda's take on unitary evolution of pure quantum states, with which I also agree.

(Lawrence, I'll hopefully get to your essay soon, as well.)

All best,

Tom

Hi Tom,

Thanks for reading our essay and as well reminding me that I promised read some essays starting with Lawrence's. I did download and read his essays and liked it very much so I'm heading over there to rate it now. Prof. Corda's essay is very close to our own and as well I had promised to read this as well -- it is downloaded but still needs reading :-(. Also if I understand correctly your essay has some connection with self-similarity so I should read this as well. Again thanks for your comments are reading our essay.

Best,

Doug

Doug, et al,

This is a copy of my respond to Doug Singleton on my essay blog.

I have read several papers by Vladimir Dzhunshaliev on octonion field theory, and Merab Gogberashvili is a familiar name as well. Trying to understand how nonassociative mathematics of operators fits into physics is really the hard part. I think that quantum mechanics is purely complex, or C. Of course classical mechanics is R. Gauge theory can be written according to quaternions H. A lot of gauge theory is done though in standard vector form without quaternions. It is interesting though that Maxwell formulated electromagnetism, the first gauge field theory, in quaternions. Field operators in a second quantization act on a Fock space basis to give quantum amplitudes. So we have a relationship that might be heuristically written as π:H --- > C. The question is then whether there is some sort of higher level structure π:O --- > H.

Spacetime I think offers a clue. A black hole horizon has some quantum uncertainty on a scale near the string or Planck length. There will then be an associative uncertainty with three quantum fields, where one of those fields is identified near the horizon. The standard approach to QFT is to assign a harmonic oscillator at every point in space, impose equal time commutators on that spatial surface with the Wightman criterion for commutation, and work from there. Yet that spatial surface on a small scale will have some noncommutative structure and this will lead to a host of uncertainties in assigning QFT operators. If there are event horizons this should lead to an associative uncertainty.

The above "maps" between C, H and O, where a similar map π:C --- > R would be the relationship between quantum mechanics and classical mechanics, are really just forms of the Hopf fibration. The relationship between quantum and classical mechanics is of course a difficult subject in its own right. With each of these "ladders" on the Hopf fibration there is some increased uncertainty. Quantum mechanics saved physics from the UV divergence that classical mechanics predicted with the hydrogen atom. Similarly this may protect physics from divergences with black holes, such as the singularity and maybe with the current big problem of firewalls.

Thanks for the good word. I had a computer crash (virus attack etc) that erased my voting code. I also had it written down on a paper that also went missing. I have not been able to vote on papers for about a week. The FQXi people have so far not serviced my request that it be retransmitted. I have also been a bit slow in reading papers this contest cycle. I see that you have a paper in the list. I seem to remember that last year your paper was riding fairly high, where mine in contrast tanked.

Cheers LC

Dear Douglas Elias & Tao,

I enjoyed your essay and agree that "energy conservation and the tunneling picture of black hole radiation allow us to show how the original "bits" of black hole information encoded in the horizon were transformed into the "its" of the outgoing correlated Hawking photons, thus providing a potential all orders in ~ solution to the black hole information loss puzzle".

It makes perfect sense and was were I was going with my essay, but omitted some further detail which agrees with this. It would have taken another 10 pages in my case to add this aspect.

However, part of the process is apparent when we note that both sides of 0 of the Fibonacci sequence, 2 remains positive. My representation of how Hawking Radiation releases energy is the -1, such that information sits evenly at the horizon and is maintained there. But also in 1-dimensional string like structures that may become Hawking radiation.

Anyway please take a look, and I'm delighted to see such a fantastic essay doesn't contradict mine!

Best wishes and kind regards,

Antony

    Hi Anthony,

    Thanks for the kind words and we will try to have a look at your essay since your description sounds like there may be some connection. Since you mention "...1-dimensional string like structures that may become Hawking radiation." you may be interested in the work of Samir Mathur. He has a host of papers which treat the microscopic degrees of freedom near the horizon as string derived states which he calls "fuzzballs". I do not fully understand Mathur's approach but it is interesting a has the good feature of giving explicit microstates for the black hole.

    Best regards,

    Doug

    Dear Doug,

    Very nice essay. Not that I dont have reservations about the black hole idea but your thoughts were well presented. So a good score from me.

    On the Planck length, what likelihood that it is physically real? My essay is here you may take a look.

    Best regards,

    Akinbo

      Hi Doug

      Richard Feynman in his Nobel Acceptance Speech (http://www.nobelprize.org/nobel_prizes/physics/laureates/1965/feynman-lecture.html)

      said: "It always seems odd to me that the fundamental laws of physics, when discovered, can appear in so many different forms that are not apparently identical at first, but with a little mathematical fiddling you can show the relationship. And example of this is the Schrodinger equation and the Heisenberg formulation of quantum mechanics. I don't know why that is - it remains a mystery, but it was something I learned from experience. There is always another way to say the same thing that doesn't look at all like the way you said it before. I don't know what the reason for this is. I think it is somehow a representation of the simplicity of nature."

      I too believe in the simplicity of nature, and I am glad that Richard Feynman, a Nobel-winning famous physicist, also believe in the same thing I do, but I had come to my belief long before I knew about that particular statement.

      The belief that "Nature is simple" is however being expressed differently in my essay "Analogical Engine" linked to http://fqxi.org/community/forum/topic/1865 .

      Specifically though, I said "Planck constant is the Mother of All Dualities" and I put it schematically as: wave-particle ~ quantum-classical ~ gene-protein ~ analogy- reasoning ~ linear-nonlinear ~ connected-notconnected ~ computable-notcomputable ~ mind-body ~ Bit-It ~ variation-selection ~ freedom-determinism ... and so on.

      Taken two at a time, it can be read as "what quantum is to classical" is similar to (~) "what wave is to particle." You can choose any two from among the multitudes that can be found in our discourses.

      I could have put Schrodinger wave ontology-Heisenberg particle ontology duality in the list had it comes to my mind!

      Since "Nature is Analogical", we are free to probe nature in so many different ways. And you have touched some corners of it.

      Good Luck,

      Than Tin

        Hi Akinbo,

        First sorry it took some time to reply -- I'm at my wife's family's home in a remote part of Thailand and my USB modem is slow. Anyway this is an interesting question about the reality of the Planck length. If one takes the physics we know at low energy as characterized by G, hbar and c (which can be combined to give a PLanck length, mass and time) one inevitably comes up with the Planck scale of 10^19 GeV, 10^{-44} sec or 10^{-35} m. But *experimentally* the only high energy scale we have directly tested is the weak scale which is at ~250-300 GeV. This was the jumping off point for the large extra dimension work of ADD which postulated that the true Planck scale coming from large extra dimensions was/could be much lower than 10^19 GeV. The last run of the LHC did not find evidence for these large extra dimensions.

        I'll mention more in this regard on your discussion page.

        Best,

        Doug

        Hi Than Tin,

        A very nice and correct quote by Feynman. And after all one of his biggest achievements was to re-formulate quantum mechanics/quantum field theory in the path integral formalism i.e. he found another way to "look at" QM.

        I very much like and appreciate analogies. One of my first works after grad school was to write down a Schwarzschild-like solution to the Yang-Mills equations using the analogy "GR and Yang-Mills theory are in some sense both non-Abelian gauge theories thus they should have similar solutions." The idea was that BHs provide confinement and thus these Schwarzschild-like solution of Yang-Mills theory might also provide the long sought after proper of confinement in QCD. The paper is "Exact Schwarzschild - like solution for Yang-Mills theories", D. Singleton (Virginia U.), Phys.Rev. D51 (1995) 5911-5914

        e-Print: hep-th/9501052. It turns out a Soviet physicist had discovered similar solutions about 20 years earlier ("Exact Classical Solutions of Yang-Mills Sourceless Equations" by A.P. Protogenov, Phys.Lett. B67 (1977) 62-64)). Actually (half jokingly) this is one thing one finds out about theoretical physics -- everything was done earlier and better by some Soviet/Russian physicist. Again this is half jokingly.

        About the use of analogies/dualities this is a very rich area of work. Almost every other paper these days has some reference to AdS/CFT which is a duality/analogy between Anti-de-Sitter space-time and conformal field theories. Thus many people appreciate dualities. I do not understand in which sense Planck's constant represents a duality so I'll go over and have a look at your essay. It may take a 1-2 days.

        Best,

        Doug

        Dear Doug, Elias and Tao,

        I just finished reading your essay. Your starting point is the previous result of Banerjee and Majhi (arXiv:0808.3688, arXiv:0805.2220) for the temperature of a black hole (eqn 7 in your essay) where backreaction is taken into account. The crucial point is your ansatz (eqn 9) for the form of the coefficients in the expansion of the quantum action in a power series in hbar, from which you obtain the regularized form of the entropy (eqn 10).

        If correct (and I haven't checked your calculations) then your result is of great importance. It would put on a firm foundation the notion that quantum mechanics and general relativity **can be** reconciled in a self-consistent framework. However, the work remains incomplete in that underlying your calculations is the implicit assumption that the continuous, commutative nature of spacetime remains the same at all scales. As Mittelman noted in previous comments, at some point non-commutative geometry should take over, leading to a black hole remnant as the end result of black hole evaporation. There should be some simple way to reconcile your calculations with those from the NC approach.

        Your work also likely has some connections with Ansari's work on black hole radiation in the framework of LQG (hep-th/0607081, arXiv:0711.1879). Overall your essay is very readable (except for the "public" who have a hard time following any mathematical arguments) and arguably deserves a place in the top three - if not at the very top.

        Cheers,

        Deepak

        Dear Douglas,

        One single principle leads the Universe.

        Every thing, every object, every phenomenon

        is under the influence of this principle.

        Nothing can exist if it is not born in the form of opposites.

        I simply invite you to discover this in a few words,

        but the main part is coming soon.

        Thank you, and good luck!

        I rated your essay accordingly to my appreciation.

        Please visit My essay.

        Hi Doug,

        Thanks for the very helpful and interesting comments over on my page and for the suggested reading here. I really liked your essay and think you deserve to do well, so hope my rating helps.

        Best wishes & kind regards,

        Antony

          Hi Anthony,

          No problem and if you read through the dimensional reduction stuff and want to discuss feel free although this is not my area but rather than my my colleague Jonas Mureika who got me interested in this and did explain to me some of the ins and outs of the idea. Actually Jonas also mentions that certain high energy cosmic ray events seem to be anomalously planar which they claim can be taken as evidence for dimensional reduction (if at high energy one has dimensional reduction then ones claims the decay products would only be distributed in a plane or line at higher energy. I'm not sure why kinematic effects would not do this, but Jonas and the authors of the paper he cites in the paper seem to think these events are odd and Jonas's explanation is dimensional reduction.

          Thanks and Best of luck,

          Doug

          Dear Douglas Singleton, Elias Vagenas, & Tao Zhu :

          I am an old physician and I don't know nothing of mathematics and almost nothing of physics,

          But maybe you would be interested in my essay over a subject which after the common people, physic discipline is the one that uses more than any other, the so called "time".

          I am sending you a practical summary, so you can easy decide if you read or not my essay "The deep nature of reality".

          I am convince you would be interested in reading it. ( most people don't understand it, and is not just because of my bad English).

          Hawking in "A brief history of time" where he said , "Which is the nature of time?" yes he don't know what time is, and also continue saying............Some day this answer could seem to us "obvious", as much than that the earth rotate around the sun....." In fact the answer is "obvious", but how he could say that, if he didn't know what's time? In fact he is predicting that is going to be an answer, and that this one will be "obvious", I think that with this adjective, he is implying: simple and easy to understand. Maybe he felt it and couldn't explain it with words. We have anthropologic proves that man measure "time" since more than 30.000 years ago, much, much later came science, mathematics and physics that learn to measure "time" from primitive men, adopted the idea and the systems of measurement, but also acquired the incognita of the experimental "time" meaning. Out of common use physics is the science that needs and use more the measurement of what everybody calls "time" and the discipline came to believe it as their own. I always said that to understand the "time" experimental meaning there is not need to know mathematics or physics, as the "time" creators and users didn't. Instead of my opinion I would give Einstein's "Ideas and Opinions" pg. 354 "Space, time, and event, are free creations of human intelligence, tools of thought" he use to call them pre-scientific concepts from which mankind forgot its meanings, he never wrote a whole page about "time" he also use to evade the use of the word, in general relativity when he refer how gravitational force and speed affect "time", he does not use the word "time" instead he would say, speed and gravitational force slows clock movement or "motion", instead of saying that slows "time". FQXi member Andreas Albrecht said that. When asked the question, "What is time?", Einstein gave a pragmatic response: "Time," he said, "is what clocks measure and nothing more." He knew that "time" was a man creation, but he didn't know what man is measuring with the clock.

          I insist, that for "measuring motion" we should always and only use a unique: "constant" or "uniform" "motion" to measure "no constant motions" "which integrates and form part of every change and transformation in every physical thing. Why? because is the only kind of "motion" whose characteristics allow it, to be divided in equal parts as Egyptians and Sumerians did it, giving born to "motion fractions", which I call "motion units" as hours, minutes and seconds. "Motion" which is the real thing, was always hide behind time, and covert by its shadow, it was hide in front everybody eyes, during at least two millenniums at hand of almost everybody. Which is the difference in physics between using the so-called time or using "motion"?, time just has been used to measure the "duration" of different phenomena, why only for that? Because it was impossible for physicists to relate a mysterious time with the rest of the physical elements of known characteristics, without knowing what time is and which its physical characteristics were. On the other hand "motion" is not something mysterious, it is a quality or physical property of all things, and can be related with all of them, this is a huge difference especially for theoretical physics I believe. I as a physician with this find I was able to do quite a few things. I imagine a physicist with this can make marvelous things.

          With my best whishes

          Héctor

          Dear All

          Let me go one more round with Richard Feynman.

          In the Character of Physical Law, he talked about the two-slit experiment like this "I will summarize, then, by saying that electrons arrive in lumps, like particles, but the probability of arrival of these lumps is determined as the intensity of waves would be. It is this sense that the electron behaves sometimes like a particle and sometimes like a wave. It behaves in two different ways at the same time.

          Further on, he advises the readers "Do not keep saying to yourself, if you can possibly avoid it. 'But how can it be like that?' because you will get 'down the drain', into a blind alley from which nobody has yet escaped. Nobody knows how it can be like that."

          Did he says anything about Wheeler's "It from Bit" other than what he said above?

          Than Tin

          Dear Douglas Singleton, Elias Vagenas, & Tao Zhu :

          I am an old physician and I don't know nothing of mathematics and almost nothing of physics,

          But maybe you would be interested in my essay over a subject which after the common people, physic discipline is the one that uses more than any other, the so called "time".

          I am sending you a practical summary, so you can easy decide if you read or not my essay "The deep nature of reality".

          I am convince you would be interested in reading it. ( most people don't understand it, and is not just because of my bad English).

          Hawking in "A brief history of time" where he said , "Which is the nature of time?" yes he don't know what time is, and also continue saying............Some day this answer could seem to us "obvious", as much than that the earth rotate around the sun....." In fact the answer is "obvious", but how he could say that, if he didn't know what's time? In fact he is predicting that is going to be an answer, and that this one will be "obvious", I think that with this adjective, he is implying: simple and easy to understand. Maybe he felt it and couldn't explain it with words. We have anthropologic proves that man measure "time" since more than 30.000 years ago, much, much later came science, mathematics and physics that learn to measure "time" from primitive men, adopted the idea and the systems of measurement, but also acquired the incognita of the experimental "time" meaning. Out of common use physics is the science that needs and use more the measurement of what everybody calls "time" and the discipline came to believe it as their own. I always said that to understand the "time" experimental meaning there is not need to know mathematics or physics, as the "time" creators and users didn't. Instead of my opinion I would give Einstein's "Ideas and Opinions" pg. 354 "Space, time, and event, are free creations of human intelligence, tools of thought" he use to call them pre-scientific concepts from which mankind forgot its meanings, he never wrote a whole page about "time" he also use to evade the use of the word, in general relativity when he refer how gravitational force and speed affect "time", he does not use the word "time" instead he would say, speed and gravitational force slows clock movement or "motion", instead of saying that slows "time". FQXi member Andreas Albrecht said that. When asked the question, "What is time?", Einstein gave a pragmatic response: "Time," he said, "is what clocks measure and nothing more." He knew that "time" was a man creation, but he didn't know what man is measuring with the clock.

          I insist, that for "measuring motion" we should always and only use a unique: "constant" or "uniform" "motion" to measure "no constant motions" "which integrates and form part of every change and transformation in every physical thing. Why? because is the only kind of "motion" whose characteristics allow it, to be divided in equal parts as Egyptians and Sumerians did it, giving born to "motion fractions", which I call "motion units" as hours, minutes and seconds. "Motion" which is the real thing, was always hide behind time, and covert by its shadow, it was hide in front everybody eyes, during at least two millenniums at hand of almost everybody. Which is the difference in physics between using the so-called time or using "motion"?, time just has been used to measure the "duration" of different phenomena, why only for that? Because it was impossible for physicists to relate a mysterious time with the rest of the physical elements of known characteristics, without knowing what time is and which its physical characteristics were. On the other hand "motion" is not something mysterious, it is a quality or physical property of all things, and can be related with all of them, this is a huge difference especially for theoretical physics I believe. I as a physician with this find I was able to do quite a few things. I imagine a physicist with this can make marvelous things.

          With my best whishes

          Héctor

            Dear All

            A standard-issue big city all-glass high-rise stands across the street from my usual bus stop. When I look up the high-rise facade, I can see the reflections of the near-by buildings and the white clouds from the sky above. Even when everything else looks pretty much the same, the reflections of the clouds are different, hour to hour and day to day.

            After I boarded the bus, I rushed to get a single seat facing four others on a slightly elevated platorm. From my vantage point, I can't help noticing the shoes of the four passengers across from my seat are not the same, by either the make , the design, or the style, and that is true even when the four passengers happen to be members of the same family.

            I could change the objects of my fascination from shoes to something else, to buttons on the dresses for example, but I do not think the result would have been any different. Diversity or Uniqueness would still rule the day! (There is a delightful essay on the subject of uniqueness by Joe Fisher in this contest.)

            I am pretty sure people are fascinated by the diversity and the uniqueness in the world, when the other side of it is the inevitable boredom of sameness every time.

            However, we have a need to know where all this beautiful and enchanting diversity comes from. Borrowing Wheelerian phraseology of "How come the quantum?", I ask "How come the diversity?" A standard physics answer is "Entropy always increases." (I am not a physicist, and I don't know if that is the final answer.)

            Whenever I'm out of my depth, I go back to my theory of everything (TOE), which is a mental brew of common sense, intuition, gut, analogy, judgement, etc. etc. , buttressed when I can with a little thought-experiment.

            The thought-experiment is simple. Imagine cutting a circle into two precisely, identical, and equal parts. Practically, there is no way we can get the desired result, because one part will be bigger or smaller in some way.

            Physics - especially quantum physics - says it don't matter, do the superposition!

            But superposition is fictive, an invention like the Macarena dance, and it has given us a cat, alive and dead at the same time.

            I have heard that angels can dance on the tip of the needle, and now I'm finding out some of us can too!

            Cheers and Good Luck to All,

            Than Tin

            Doug,

            Many thanks for the suggested reading - I will take a look. No panic about my essay - there are so many to get through - it is an enjoyable, but massive task.

            Best wishes,

            Antony