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Too Hard for Science? Creating naked singularities

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Neutrino beams might create such enigmas, but dare we risk making anything so unpredictable?

In "Too Hard for Science?" I interview scientists about ideas they would love to explore that they don’t think could be investigated. For instance, they might involve machines beyond the realm of possibility, such as particle accelerators as big as the sun, or they might be completely unethical, such as lethal experiments involving people. This feature aims to look at the impossible dreams, the seemingly intractable problems in science. However, the question mark at the end of "Too Hard for Science?" suggests that nothing might be impossible.

By the way, who would you like to see on Too Hard for Science? this Friday? Inventor Dean Kamen? Science fiction novelist David Brin? Stanford Prison Experiment creator Philip Zimbardo? Tweet your vote to @cqchoi by 12 noon Eastern time on Wednesday.

The scientist: Martin Bojowald, associate professor of physics at Pennsylvania State University.

The idea: Among the greatest challenges in physics are areas where our understanding of the known laws of physics break down — infinitely dense points known as singularities. The universe is conjectured to have been born from a singularity, and singularities are thought to exist inside black holes.

To better understand these mysteries, "being able to look at one of them could be highly educational," Bojowald says. "To do so, we could try to make a black hole that is sufficiently long-lived, which requires a large amount of mass to be compressed into a tiny region."

One major problem with such an experiment is that the singularity of a black hole is in principle obscured by an event horizon, a boundary past which nothing can return. This means researchers could not get data back from any probe sent through an event horizon.

However, Bojowald notes that naked singularities could in theory exist, ones not covered by event horizons. Scientists in principle could create such singularities by compressing very light particles such as neutrinos sufficiently quickly. One would want to arrange neutrino emitters spherically, aim them at one central point and ramp up their beam intensity rapidly. Such a singularity would not need to be massive at all — maybe equal in mass to a single electron.

"It would not be naked for long if the mass is small," Bojowald says. Still, "even a brief duration could be quite exciting." If we could look at one, "entirely new observations would become possible, almost like seeing another universe. It would be as though we had always been living in a closed room, and suddenly someone opened the window."

"Once we produce a naked singularity, probing it will be the easy part," Bojowald says. "We point a lot of detectors at the central point looking at whatever comes out. Since we don’t know what happens at the naked singularity, our best chance is to capture as much information as we can get for radiation of all kinds of energies. Some theory of quantum gravity is likely to be relevant to describe a naked singularity, so we should look especially for high-energy particles."

The problem: Directing neutrinos into beams is tricky at best because they only weakly interact with the electromagnetic fields that scientists use to manipulate electrically charged particles. It’s not impossible — neutrinos are produced by decaying particles such as muons that do have an electric charge, "and if the muons form a beam of high velocity, the neutrinos are predominantly emitted in the forward direction. In this way, one obtains a beam," Bojowald says. Still, the intensity of these beams is far below what would be required to generate a naked singularity, "and there would be no way to focus the neutrinos on a single point."

In addition, "general relativity, even though it does allow naked singularities, also indicates that they are unlikely to form," Bojowald says. "We would need very good control of the neutrino beams, making the experiment even more difficult."

A greater concern may be that since our understanding of the known laws of physics break down around singularities, "a naked singularity would be unpredictable according to current theory, so the experiment would be risky," Bojowald says. "We do not know what could come and hit us."

The solution? Instead of attempting to create naked singularities, researchers could try and find them in nature instead. Computer simulations have suggested that black holes could essentially spin fast enough to shed their event horizons and reveal naked singularities, although researchers suggest other factors such as gravitational effects might keep this from happening.

Image of Martin Bojowald from Penn State’s site.


If you have a scientist you would like to recommend I question, or you are a scientist with an idea you think might be too hard for science, email me at

Follow Too Hard for Science? on Twitter by keeping track of the #2hard4sci hashtag.

About the Author: Charles Q. Choi is a frequent contributor to Scientific American. His work has also appeared in The New York Times, Science, Nature, Wired, and LiveScience, among others. In his spare time, he has traveled to all seven continents. Follow him on Twitter @cqchoi.

The views expressed are those of the author and are not necessarily those of Scientific American.


Comments 23 Comments

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  1. 1. Shade1974 11:49 am 04/18/2011

    And what a brutal weapon a neutron beam can be ;) . Very difficult to shield against with standard EM forcefield technology since EM is more or less ineffective against neutrons. The only decent counters I can think of both require an even higher level of tech. You could use a beam of anti-matter neutrons to disrupt the incoming beam. Even a very small number of them would create such an energetic reaction in the beam pathway that it would act against the remaining neutrons, scattering them. The other option might involve gravity field deflection, but we are missing the fundamental understanding necessary to even know if such a thing is possible.

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  2. 2. ennui 9:11 pm 04/18/2011

    Yes, it also can be used to create an ING as a weapon.

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  3. 3. jtdwyer 9:30 pm 04/18/2011

    I understand that this article refers to hypothetical neutrino beams – not neutron beams. Neutrons are the massive electrically neutral components of atomic nuclei, whereas neutrinos hardly interact with matter at all: they are extremely low mass decay products of short-lived particles. They do have some small mass but not so much as to prevent them from attaining high velocities…

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  4. 4. jtdwyer 10:01 pm 04/18/2011

    Alternatively, the expulsion jets of an ‘active’ black hole may be fundamental to the process of ‘ingesting’ matter. I suggest that black holes contain no matter – that they are merely the radial contraction of spacetime produced by the extraction of gravitational energy from ingested matter. This can be inferred from the process of progressive dimensional compaction of matter processed by gravitational collapse – an extrapolation of the process producing neutron stars by releasing electrons and converting protons.

    In this scenario, ingested matter accelerated to extreme velocities materially decomposes: its binding mass energy and perhaps even the strong force are separated from the spatially unbound fundamental particles. The gravitational energy of the ingested matter’s mass is locally retained, directed to the singular, dimensionless focal point of the black hole.

    All residual material energy is expelled from the black hole’s polar jets by centripetal force. This nearly massless material residue consists of pointlike, dimensionless fundamental particles accelerated to exceedingly high velocities.

    This general process naturally explains black holes’ extreme gravitational effects without requiring that they somehow contain enormous amounts of matter within some unphysical singularity or some imaginary undetected dimensions. The dimensionless singularity is simply the directional focal point of retained gravitational energy, while all physical dimensions of spacetime have been locally contracted and retained.

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  5. 5. Shade1974 11:27 am 04/19/2011

    Wow yes, I was reading too quickly. You are correct. Neutrinos, even Tau neutrinos, make for a much less effective weapon. I thought the point of organizing a singularity was to get a lot of mass into a small space, but my version with neutrons might not be naked. Realistically, my first thought would not be to rely on fermion states at all (even neutrinos). I mean, the exclusion principle is pretty difficult to overcome even if you get the beam sorted out, and I think both neutrons and neutrinos count as fermions. Why not start with a Bose-Einstein condensate so that you can pack more of them into one place and keep packing on the pounds until something interesting happens? Maybe you can make it naked by spinning it?

    I think right now the notion of a mathematical singularity is likely to be a poor fit with what actually happens. The whole point of supercolliders is that in extreme conditions the fundamental laws change. The main thing that has been consistent is that we keep observing cool new things that defied our predictions. The same would likely be true in the case of a singularity experiment. It’s likely a lot more complicated than simply a transformation into "gravitational energy". But until we build it we can’t be sure.

    Anyway, thanks for the catch.

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  6. 6. davidmac 12:44 pm 04/19/2011

    Naked singularities are a non-starter, as singularities in general do not exist. Ultrawave theory dismisses the idea of singularities by showing that matter is the concentration of strings and branes into tori that can be compressed beyond standard particle types to form larger tori that are at the centers of black holes. It is time that the scientific community finally accept the ultrawave proposal. I have been waiting since 2001 for this eventuality, but have to endure yearly incremental improvements to the Standard Model that brings it closer and closer to the ultrawave paradigm. Ultrawave theory (UT) is so much simpler and more logical than the SM that anyone who seriously examines it can see how much more realistic is its underpinnings. There are so many experiments that can be done to prove or disprove UT that it makes no sense not to attempt one immediately. With the possibility of FTL communications on the line, it seems an imperative of science to do just that.

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  7. 7. jtdwyer 2:52 pm 04/19/2011

    You’re welcome, and can return the favor the next time I err…

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  8. 8. gwmckenzie 4:23 pm 04/20/2011

    As an alternative to investigation of an actual singularity, would it be more practical to conduct investigations into small, but increasingly dense "objects"? Instead of a "utrino emitter", what about choosing another, more easily manipulated, particle in the same spherical arrangement? Would data from a series of experiments, at increasingly higher densities, reveal anything useful about what the properties of the singularity would be?

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  9. 9. jack.123 7:27 pm 04/20/2011

    You are right about the mass in a black hole except that the mass in the singularity and whats below the event horizon is frozen at a fixed amount because everything below the EV is at Time=o and has no wave function thus all other mass in a black hole is forever held at held at the EV.

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  10. 10. mwagner17 3:26 pm 04/21/2011

    Too hard for science? Oh, come on! Almost everything we do in scientific research today was "Too hard for science" 100 – or even 50 – years ago!

    As for naked singularities, I suppose that a black whole which is spinning fast enough for a point on its event horizon to be moving superluminally might be able to throw-off that event horizon but I suspect that to get there we are going to have to develop a working unified-field-theory OR a working theory of quantum gravity.

    Frankly, I think that the Standard Model of particle physics will, in the end, prove to be too contrived and too cumbersome to reflect reality. I am skeptical about string theory as well. Today, our mathematics is just not robust enough to address these complex issues.

    I suspect that TIME is the key. That three spacial dimensions and one temporal dimension is the clue that will cause us to rethink the true nature of the Universe, of entropy, and of time itself.

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  11. 11. Wilhelmus de Wilde 12:03 pm 04/22/2011

    I don’t understand why Bojowald is still running after singulairities, they merely cannot exist in our 4D universe, where there are limits , for example the Planck scale, 10^-33cm, after this wall we have no control any more, it is there where string theorists are creating their enrolled 10 dimensions, scientists place these singulairities even with no dimensions at all, at the beginning of the Big Bang (what Big Bang) aand at the heart of Black Holes. I develloppped the idea, it is an idea because the truth cannot be found, that after the Wall of Planck we enter a different dimension that I called or the FIFTH dimension or TOTAL SIMUTANEITY (see my essay on FQXi : So in my opinion it is not only too hard for science to create naked singulairities but also for reality.

    keep on thinking

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  12. 12. toohardforscience 12:05 pm 04/22/2011

    In the very beginning of every "Too Hard For Science?" piece, you might note the following:

    "In ‘Too Hard for Science?’ I interview scientists about ideas they would love to explore that they don’t think could be investigated… However, the question mark at the end of ‘Too Hard for Science?’ suggests that nothing might be impossible."

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  13. 13. kenkoskinen 9:30 pm 04/22/2011

    The article delivers on its intention and that is to create a fanciful discussion. We are on the fringe edges of physics and that’s a fun place to speculate. Judging by the comments there are some ideas which are outside of the box (real and unreal … whose to say?) My only advice is: If you realize this is part of speculative science it might help you to contain your passion for your pet theory. The people currently working in the physics world aren’t all morons and you aren’t the only one who thinks. After all, you and everyone else can be wrong.

    The first question is whether we can create even a micro-black hole, never mind a so-called naked one. Perhaps we might see one eventually during an experiment on the LHC? The second question which has been addressed is whether singularities even exist? These are predicted via General Relativity but perhaps some quantum feature prevents them. If so GR would NOT be directly contradicted as it would only mean another principle of physics intervened. Of course we don’t know what is (or specifically goes on) inside black holes but they must contain mass/energy or they wouldn’t gravitate and of course they do.

    The third question relates to detections. Even if a naked black hole could be created we would still face the problem of how to detect things/events at depth. Even if we had a neutrino black hole what do you fire at it so it could be detected? Maybe you’re thinking another neutrino … okay … why wouldn’t it just bind up within the neutrino bulk? Even if you detected a neutrino coming out the other side, how would you know it wasn’t one that was dislodged from the bulk?

    In any case the questions are many and the answers are few. I admit it is fun to think about.

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  14. 14. bernardpalmer 1:24 am 04/23/2011

    We are really on the edge with this one.

    First off I doubt we can have ‘singularities’ because it is singular therefore there is only one Singularity and it should be the same one at the centre of each black hole. This implies that the whole Universe is possibly a naked Singularity with pockets of rotating mass inside it. So everything has the same centre.

    Next if that is true then the whole Universe is alive. A fish swimming in water is itself predominately water but we never see the fish as an extension of the water that it swims in. A bit like the eye is the extension of the brain. Possibly the brain becomes an extension of the Singularity. And as everything that rotates has a non rotating centre or zero point then everything is the Singularity.

    So take your pick. You are surrounded by the Singularity. No need to chase fleeting particles. Just build a very cheap AC generator so everyone can have one because there is more energy on the other side of the zero point than there is on this side. That’s what you’ve got to get at, cheap clean unlimited energy.

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  15. 15. BrainWorld 5:45 pm 04/24/2011

    A singularity is a theoretical mathematical point at which mass has been compressed into a state at which its own gravity holds it together. Nobody has ever observed one directly although there is good indirect evidence for their existence at the center of our galaxy and probably other galaxies too, where they are usually termed "black holes". Such black holes would be quite massive, on the order of millions or billions of solar masses. There has also been a great deal of speculation about sufficient energy being created through the collision of high energy protons at CERN’s Large Hadron Collider to form "microsingularities", essentially tiny black holes of much less mass than stellar black holes, but having similar properties. The properties of any singularity include the formation of an "event horizon", a theoretical shell surrounding a singularity at a radius determined by its gravity such that anything reaching and/or passing that radius must be inevitably drawn into the singularity by the force of gravity which sustains it (the event horizon is not made of anything, it is simply a mathematical boundary where the force of gravity is greater than any other force that might act counter to it). For a large stellar black hole that radius might be thousands of miles, for a microsingularity the radius of the event horizon might be on the order of a proton’s radius, but in either case the result is the same: anything touching or passing that radius is going to be gravitationally attracted into the singularity with irresistible force. Even light cannot escape it.

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  16. 16. BrainWorld 5:52 pm 04/24/2011

    Speculation about "naked" singularities must necessarily involve some process by which the event horizon either vanishes through some kind of magic or else the event horizon resides within the radius of the singularity itself. But a singularity has no radius, at any mass considered (e.g. billions of solar masses) it is always a mathematical point with a radius of zero. It is impossible to have an event horizon (or anything else) with a radius less than zero, so a "naked singularity" is an impossibility on a physical basis, only magic remains to explain how one might exist and I conclude that any person calling themselves a scientist who seriously puts forth the idea of magical mechanisms is no scientist. So while the idea of a "naked singularity" is appealing, it is entirely in the realm of Harry Potter and scientists considering how one might be created simply fail to understand the physics of the situation. In this article we see the same phenomenon: there is no mechanism stated by which neutrinos might form a singularity, the author might as well be talking about Harry Potter creating singularities with his magic wand. And in fact there is no mechanism by which a naked singularity could be formed because by the very definition of a singularity, without an event horizon external to the singularity there would not be sufficient gravitational force to hold it together. It’s like talking about light with zero energy or water containing no hydrogen and oxygen, not only physical impossibilities but physical absurdities. Anyone interested in singularites of any kind should disabuse themselves entirely of the magical notion of "naked" ones even if they do sound sexy, just as any decent life scientist will disabuse themselves of the notion of unicorns.

    There is an interesting application for microsingularities if they do get created at CERN’s LHC however: they might be used for time travel since one of the properties of singularities is that they will distort space and time, particularly when spinning. It’s speculative but at least it doesn’t require Harry Potter’s intervention, the mechanisms are there. If you’re interested you should look into John Titor’s story, see for starters.

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  17. 17. kenkoskinen 12:53 am 04/26/2011

    BrainWorld, what you say is sound but so is the possibility of black holes without singularities.Stephen Hawking was the first to see there should have been a troubling singularity at the Big Bang. If that were the case we and the universe shouldn’t be here. However here we sit, within an expanding universe. Either some unknown principle/process smeared out the cosmic singularity or there wasn’t a Big Bang.

    Any point of infinite density and zero volume is disturbing to our minds. You might as well also call singularities "magic," or hide them behind the idea of them being "a mathematical point." Arguably you could also say all of physics is a set of "mathematical points." In other words a singularity is nonsense to our current understanding of physics even though GR predicts them.

    If there wasn’t a cosmic singularity then maybe they are also outlawed in stellar or galactic black holes. One could add micro-black holes to the list if indeed they exist. Of course what I’m suggesting requires new physics such as a theory of quantum gravity or some other micro-mechanism or order perhaps even below the quantum level. I agree magic shouldn’t be appealed to in science but good theories often begin as speculative.

    Of course so-called naked black holes are double trouble; (1) on the theoretical level, as you point out (2) and they do not have any detection history. For those interested see You can freely download:"The Three "S’s" of Science & the Physics of Humpty Dumpty. Just click on any "Downloads" button and click on the essay.

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  18. 18. BrainWorld 4:46 pm 04/26/2011

    @kenkoskinen you are not making sense, to say "…singularity is nonsense to our current understanding of physics even though GR predicts them" is a contradiction because they’re NOT "nonsense" (or even magic) if predicted by GR. Nor is "new physics" required to explain them (or microsingularities for that matter), existing physics works fine for tha. They just seem strange to us because their characteristics lie outside our realm of ordinary experience and because they’re still unproven. But SOMETHING must happen when sufficient mass accumulates that physics says a singularity must be formed, so we’re still safely in the range of scientific speculation by discussing them and making attempts to mathematically determine what their characteristics might be from first principles. The same CANNOT be said for "naked" singularities however (which was my point), because they are physically impossible on any mathematical or first-principle basis; only magic can explain a naked singularity. Notice how the author of this article says absolutely nothing about any MECHANISMS by which neutrinos might create one, other than blasting neutrinos at each other? That explains nothing. So when you say "I agree magic shouldn’t be appealed to in science but good theories often begin as speculative" that’s all fine and good as far as it goes but ANY such theory needs to have some mechanism(s) connecting it to reality, whereas in this case the author might have just as well been talking about creating unicorns from neutrinos and it wouldn’t have changed the tone and tenor of the article one bit.

    You mention the Big Bang and that’s a good example of theory attempting to explain observations, connecting suggested mechanisms to reality as is required by real science. In contrast, this article as presented is not real science and does not belong in a publication that purports to be about science. Whether a singularity existed to bring about the Big Bang or not however is outside the scope of this article unless one is going to propose that it was a "naked" singularity along with some explanation about what that might bring to the Big Bang theory (which in my opinion is terribly deficient in explanatory power and wrong on a physical basis but at least it’s still valid scientific speculation).

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  19. 19. kenkoskinen 8:22 pm 04/26/2011

    @BrainWorld I think Charles Choi’s "Too Hard for Science?" articles in part intends to stimulate thought and fanciful discussions. I agree with you about the deficits on the concept of naked singularities but fail to see any harm in the discussion; after all you & me are participating. To be fair to Choi he never specifically appealed to magic. However, I agree he lacks explanatory power and omits the mechanism issue. To be fair to you, these lacks do come across much like you characterize.

    The reason why singularities are nonsense is they don’t make sense. We don’t know what a point of infinite density and zero volume is! Just because GR predicts them doesn’t mean they make sense. The process of science often evolves upon previous theories. GR goes beyond (and subsumes) Newtonian gravitation. GR is a great theory but it isn’t the final theory or theory of everything (TOE), sometimes called the unified field theory. Einstein spent much of his later years searching for the final unifying theory. Others continue to this day.(I plan to publish my TOE later this year).

    I never said or implied that new physics is required to explain singularities "or microsingularities for that matter." GR already does that. You missed my point. New physics would be needed to explain how the universe by passed the Big Bang’s cosmic singularity. Hawking used GR to predict or "post-dict" one should have been there. It should have had devastating consequences. The same new physics could be used to model other kinds of black holes without singularities. In other words the GR singularity conclusion could be over ridden by some new theory or principle. It doesn’t necessarily have to mean they wouldn’t have event horizons, after all the galactic black holes are completely dark yet gravitate.

    Also be aware that in these kinds of discussions people often include related material outside of the specific context of the article. It’s part of the fun!

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  20. 20. BrainWorld 4:03 am 05/4/2011

    @kenkoskinen you’re absolutely right about the discussion/fun part but I’m often troubled by the encroachment of pseudoscience in venues like Scientific American that should be more responsible about their content. You likely saw some of the early comments which were completely delusional and this article as it stands isn’t far from them. Sorry to be a wet blanket, I suppose I wouldn’t have minded if this was

    Okay so what MIGHT be some properties of a "naked" singularity? That has to depend on its composition and structure. It seems to me that in order to begin to consider this we have to abandon the concept of "singularity" as a mathematical point and think instead of "black holes" which do not contract to a point but retain some diameter, however small it may be. This might be what you were alluding to when you referred to "… the possibility of black holes without singularities"? So let’s say we’re talking instead about "naked black holes" in a universe where point-source singularities are only mental constructs that never actually exist.

    In that special case it is possible to imagine a black hole with a radius equal or almost equal to the radius of its event horizon. If the radius of the event horizon was shorter than the radius of the black hole by say anything less than 0.5 Planck length (just for starters), gravitation would hold it together but the black hole’s "surface" would be outside the event horizon by something less than 0.5 Planck length and "naked" in the sense that radiation could escape from it.

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  21. 21. BrainWorld 4:05 am 05/4/2011

    However, you say "We don’t know what a point of infinite density and zero volume is" and I’ll just separate out the zero volume part because density is mass per unit volume and at zero volume you don’t necessarily get infinite density, you get a divide by zero error and I don’t know what that might mean in any physical terms. Zero volume is easier however because Einstein taught us that time slows down as an object approaches the speed of light, and at the speed of light time goes to zero. An object approaching the speed of light will also contract in the direction of its movement, approaching zero length. Consequently for light leaving the most distant galaxy to fall on our retinas after traveling billions of years, as far as the light is concerned no time has passed, and the photon or wave as you prefer exists in its own frame of reference continually along its path, it is not at one place at one time and farther along at another place later because it experiences no time. This is true for all the light in the universe, which has an existence outside our time-bound frame of reference that spans the entire universe with zero time and zero dimension i.e. for light the entire universe is a mathematical point. So I don’t have trouble with zero volume because it has to be true for the universe in light’s frame of reference if Einstein is correct, and my money’s on the big guy.

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  22. 22. Wilhelmus de Wilde 11:36 am 05/5/2011

    I like very much the explanation of Brainworld.
    If time at the velocity of light becomes zero, so does not proceed, there is no "observable" change, no longer an a before the b, so no causality any more, outside the photon the universe can change, so is observable, this non causality is only for the photon moving at the speed of light, in his own frame of reference , here we meet the true relativity.

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  23. 23. Wilhelmus de Wilde 11:19 am 05/6/2011

    Before I fell asleep, some other ideas came along, Brainworld accepts zero length and time, but our universe has limits in length and time being the Planck length and time. So in our 4-d causal deterministic universe we cannot have zero quantities.
    What happens than with photons travelling at the speed of light ?
    At the speed of light (wich is another limit in our universe) the length of the photon approaches the Planck length and after this barrier there is no more causality, no more one before two etc. this means that time does not "flow" anymore in the way that we perceive it, in our perception time is no more progressing, it stands still, so there is no more discrepancy with brainworlds view.
    But : untill the photon is not "observed" it is a wavefunction isn’t it ? How do we describe a wavefunction travelling at the speed of light ? The same as for particles ? Are "possibillities" of location the same "entities" as particles ? I don’t think so. Perhaps these "possibillities" can travel faster as light, in order to achieve an observation, or the wavefunction is just like a "field" where we can "meet" a particle ?

    I would be obliged to hear your comments.

    keep on thinking


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