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Is Dark Matter a Glimpse of a Deeper Level of Reality?

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


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Two years ago several of my Sci Am colleagues and I had an intense email exchange over a period of weeks, trying to figure out what to make of a new paper by string theorist Erik Verlinde. I don’t think I’ve ever been so flummoxed by physicists’ reactions to a paper. Mathematically it could hardly have been simpler—the level of middle-school algebra for the most part. Logically and physically, it was a head-hurter. I couldn’t decide whether it was profound or trite. The theorists we consulted said they couldn’t follow it, which we took as a polite way of saying that their colleague had gone off the deep end. Some physics bloggers came out and called Verlinde a crackpot.

For those who know Verlinde, that label hardly fits. He is a brilliant theorist, and the amount of discussion his paper provoked suggested that most of his colleagues saw something in it. The whole story caught the eye of New Scientist and the New York Times, but ultimately we at Sci Am opted for watchful waiting. I caught up with Verlinde this spring during a workshop at the Kavli Institute for Theoretical Physics. He has doubled-down on his original paper, and his colleagues’ reaction hasn’t changed. One told me: “There are a lot of ideas he’s bringing together in an interesting way, but it’s a little hard for us to decipher, so I’m withholding judgment.” All he has really done, though, is take a general sentiment among string theorists and follow it to its logical conclusion.

String theorists and other would-be unifiers of physics face a basic problem. The theories they seek to unify, quantum field theory and Einstein’s general theory of relativity, are well-grounded and well-tested, yet mutually incompatible. Reconciling them will demand that some deeply held intuition must give way. One such intuition is that the world exists within space and time. Participants at the Kavli workshop were inclined to think that space and time are not fundamental, but emergent. The universe we see playing out in space and time may be just the surface level, where we float like little boats while leviathans stir in the deep.

Black holes provide the strongest argument for this point of view. The laws of gravity predict that these cosmic vacuum cleaners obey versions of the laws of thermodynamics, which is strange, because thermodynamics is the branch of physics that describes composite systems, such as gases made up of molecules. A black hole sure doesn’t look like a composite system. It just looks like a warped region of space that you would do well to stay away from. For it to be composite, space itself must be.

In that case, black holes represent a new phase of matter. Outside the hole, the universe’s “degrees of freedom”—all that its most fundamental building blocks are capable of—are in a low-energy state, forming what you might think of as a crystal, with a fixed, regular arrangement we perceive as the spacetime continuum. But inside the hole, conditions become so extreme that the continuum breaks apart. “You can make spacetime melt,” Verlinde told me. “This is really where spacetime ends. To understand what goes on, you need to use these underlying degrees of freedom.” Those degrees of freedom cannot be thought of as existing in one place or another. They transcend space. Their true venue is a ginormous abstract realm of possibilities—in the jargon, a “phase space” commensurate with their almost unimaginably rich repertoire of behaviors.

Verlinde’s 2010 paper applied this reasoning to the laws of gravity themselves. Instead of being a fundamental force of nature, as almost all physicists since Newton have thought, gravity may be an “entropic force”—a product of some finer-scale dynamics, much as the pressure force in a gas arises from collective molecular motions. At Kavli he went further and argued that the notion of emergent spacetime transforms our entire conception of the universe. “If you realize there’s much more phase space than we usually assume—much more—you will think about cosmology differently,” he argued.

For starters, dark matter may be a glimpse into the depths. To account for anomalous motions within galaxies and larger systems, astronomers think our universe must be filled with some invisible material that outweighs ordinary matter by a factor of five to one. They have never detected the material directly, though, and for something that is supposed to be so overwhelmingly dominant, dark matter has a puzzlingly subtle effect. The anomalous motions occur only in the unfashionable outskirts of galaxies. Stars and gas clouds out there move faster than they should, but don’t do anything truly wacky—it is as if the gravitational field of the visible galaxy were simply being amplified.

Consequently, some astronomers and physicists suspect there may be no dark matter after all. If you notice the floorboards in your house are sagging, as if there is too much weight on them, you might conclude there is an 800-pound gorilla in the room with you. You see no gorilla, so it must be invisible. You hear no gorilla, so it must be silent. You smell no gorilla, so it must be odorless. After a while, the gorilla seems so improbably stealthy that you begin to think there must be some other explanation for the sagging floorboards—the house has settled, say. Likewise, perhaps the laws of gravity and motion which led astronomers to deduce dark matter are wrong. “I think dark matter will be a sign of another type of physics,” Verlinde said.

The leading alternative to dark matter is known as MOND, for Modified Newtonian Dynamics. Verlinde has reinterpreted MOND not just as a tweak to the laws of physics, but as evidence for a vast substratum. He derived the MOND formula by assuming dark matter is not a novel type of particle but the vibrations of some underlying degrees of freedom—specifically, vibrations produced by random thermal fluctuations. Such fluctuations are muted and become conspicuous only where the average thermal energy is low, such as in the outskirts of galaxies. Astoundingly, Verlinde even derived the five-to-one ratio. “I started seeing this as a manifestation of this larger phase space,” he said.

MOND is super-iffy, as cosmologist Sean Carroll has detailed in a series of blog posts over the years, most recently this one. I’m inclined to agree, but one thing gives me pause. MOND manages to account for a wide range of anomalous galactic motions with one simple formula. Even if MOND doesn’t overturn the laws of physics, it has shown that dark matter behaves in a simple way. All the complicated dynamics of dark matter must somehow settle down into a very regular pattern. Dark-matter modelers tell me they have yet to explain this.

Verlinde bucks conventional wisdom not only on dark matter, but also on much of the rest of cosmology. For instance, he has reintroduced elements of the steady-state theory that most cosmologists thought they had ruled out in the 1960s. In his model, all matter—ordinary as well as dark—consists of vibrations of the underlying degrees of freedom and so is being created and destroyed all the time. In fact, the same degrees of freedom also explain dark energy, thereby unifying all the components of the universe. What differentiates these components is how fast they respond: ordinary matter is the surface chop, dark matter the languid but powerful deep currents, and dark energy the quiet bulk of the sea. As for another leading cosmological theory, cosmic inflation, he doesn’t think much of that, either.

The grander his claims become, the less plausible they seem. Still, Verlinde has captured theorists’ sense that cosmological mysteries signal a new era of physics. The impulse to explain dark matter and dark energy as signatures of a deeper reality, rather than a bolt-on to current theories, arises not only in string theory but also in alternatives such as loop quantum gravity and causal set theory. And if Verlinde is wrong and spacetime really is a root-level feature of our world, what other intuition will have to give way? What other thing that we thought we knew for sure is wrong?

Diagram courtesy of Erik Verlinde

George Musser About the Author: is a contributing editor at Scientific American. He focuses on space science and fundamental physics, ranging from particles to planets to parallel universes. He is the author of The Complete Idiot's Guide to String Theory. Musser has won numerous awards in his career, including the 2011 American Institute of Physics's Science Writing Award. Follow on Twitter @gmusser.

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





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  1. 1. Bora Zivkovic 12:55 pm 06/11/2012

    Hey, nice new digs here! Looking forward to your posts very much!

    Link to this
  2. 2. caleb_scharf 4:11 pm 06/11/2012

    Terrific post!

    Link to this
  3. 3. jtdwyer 4:41 pm 06/11/2012

    The speed at which planets orbit the Sun (which contains 99.86% of total Solar system mass) varies depending almost entirely on their distance from the Sun.

    The characteristic plot of planets’ orbital velocities as a function of radial distance is referred to as a Keplerian rotation curve. In the 1970s, astronomers studying the rotation curves of objects within the disks of spiral galaxies expected each to comply with Keplerian rotation curves, ‘just like planets in the Solar system’ (see Vera Rubin et al.). They didn’t. Instead, rotational velocities were relatively constant regardless of radial distance.

    To make a Solar system whose planets’ rotational velocities remained flat or nearly constant like spiral galaxies’, astronomers envisioned that an enormous undetected peripheral mass must be present, extending the mass distribution to enormous radial distances. Their models confirmed this expectation, and compelling evidence of dark matter halos was convincingly conceived.

    The problem was that, as Newton had explained in his Principia, Kepler’s laws of planetary motion provided reasonable approximations only for orbital bodies of relatively negligible mass, like planets in the Solar system.

    For vast distributions of billions of massive objects, like galactic disks, discrete objects do not independently orbit any central massive object. Each massive object most strongly interacts with its neighboring masses. As a result, galactic disk objects generally rotate around their collective center of mass as loosely bound clumps of massive objects, not individual, independently orbiting objects.

    Galactic dark matter was only necessary to correct astronomers’ misconception that stars in the disks of spiral galaxies should orbit just like planets in our Solar system! Please see: Rubin, et al., (1980), “Rotational properties of 21 SC galaxies with a large range of luminosities and radii, from NGC 4605 /R = 4kpc/ to UGC 2885 /R = 122 kpc/”, http://dx.doi.org/10.1086/158003 http://adsabs.harvard.edu/abs/1980ApJ…238..471R
    As stated in section VIII. “DISCUSSION AND CONCLUSIONS”:
    “1. Most galaxies exhibit rising rotational velocities at the last measured velocity; only for the very largest galaxies are the rotation curves flat. Thus the smallest Sc’s (i.e., lowest luminosity) exhibit the same lack of a Keplerian velocity decrease at large R as do the high-luminosity spirals. This form for the rotation curves implies that the mass is not centrally condensed, but that significant mass is located at large R. The integral mass is increasing at least as fast as R. The mass is not converging to a limiting mass at the edge of the optical image. The conclusion is inescapable that non-luminous matter exists beyond the optical galaxy.”

    While astronomers very precisely detailed their kinematic observations of galactic rotation, it was never formally established that there was any basis for the expectation that galaxy rotation should comply with Keplerian rotation curves or the laws of planetary motion, which is actually invalid.

    In more recent years it has been demonstrated that the rotational characteristics of spiral galaxies can be described using Newtonian dynamics and universal law of gravitation, without dark matter or modified gravity. Please see:
    Feng & Gallo, (2011), Modeling the Newtonian dynamics for rotation curve analysis of thin-disk galaxies, doi:10.1088/1674-4527/11/12/005 arXiv:1104.3236v4

    Link to this
  4. 4. Percival 9:59 pm 06/11/2012

    Welcome to SA, George- great first blog.

    jtdwyer- it seems to me that your cites make some assumptions that need verifying. If so-called dark matter is just non-luminous ordinary matter (black holes, stars, planets, etc.), it must must be assumed to have been ejected from the star-forming deeper reaches of the galaxy long ago; it’s dark because ejected stars are so old and thus cold that we can’t make them out in the visible *or* IR. Planets, black holes, and smaller stuff must have also been ejected long enough ago to grow too cold to see.

    The other assumption I mentioned is that whatever it is exists way out where new stars can’t form because there isn’t enough gas to make them out of.

    Well, how far out is there enough gas to support star formation, exactly? As far as I know, gas isn’t ejected in the galaxy’s plane in theories of galaxy formation (not counting collisions) like planets and stars can be, so the star-forming region should shrink over time despite any offset say from gas ejected at the poles that falls back.

    In any case, is the galaxy old enough to have formed and ejected that much non-luminous matter?

    On the other hand, it may have formed out there when there *was* enough gas to make stars etc., before the star-forming region shrank to its current dimensions.

    Does the timing jive with what we think we know of the galaxy’s age, the rate of contraction of the star-forming region, its replenishment rate by polar jets, and so on? If not, what must we re-think?

    Even if our array of orbital eyes can’t see such stuff orbiting out own galaxy (because of the intervening dust) we should be able to pick out an IR signature of dark/non-luminous whatever orbiting other galaxies. Such signatures might be available in already taken images. Somebody should look.

    Link to this
  5. 5. Glendon Mellow 11:57 pm 06/11/2012

    Fascinating first post!

    Link to this
  6. 6. vinodsehgal1957@yahoo.com 6:45 am 06/12/2012

    WMAP CMB studies have established the flatness of universe on large scales. Density of luminous matter and luminous energy does not lead to flatness, therefore, scientists are required to invoke dark matter and dark energy to arrive at flatness. So apart from orbital velocities of stars and galaxies, flatness is also one reason for hypothesizing dark matter and dark energy. This is another issue that initially dark energy was hypothesized during the last decade of 20th century to explain the accelerated expansion of space.

    All the above problems are cropping up since scientific knowledge of space and space expansion is quite rudimentary. Of late during the past 2-3 decades, there has been plethora of theories carrying load of speculation and computer simulations. Irony of the issue is that present day technological advancement are incapable of carrying empirical testing of such theories.

    Link to this
  7. 7. vinodsehgal1957@yahoo.com 8:50 am 06/12/2012

    Theoretical Physicists of 21st century, tending to penetrate the deeper layers of reality, are moving towards that direction of reality and truth which sages and meta physicists of East have been describing since millenia. But such sages are not having language, nomenclature and terminology which Physicists speak of .

    Though not much aware of other religions, but sages of many spiritual school of thoughts in India have described that this physical world, in which we reside and comprising of space, matter and energy of modern Physicists, is the outer sheath of bigger universe. This physical world emerges out and and resides within another world nomenclatured as astral world (Sukshma Jagat). The way this physical world has its own space, matter, energy, physical laws, inhabitants with specific biology with or without intelligence, similarly astral world has also its own space, energy, matter, inhabitants with their own biology. Astral world has to its own set of physical laws.

    Astral world is not another universe of any multiverse or omniverse as quantum physicists or string theoreticians envision of. Astral world is right here under our nose in Physical world infinitesimal close to it.

    I suspect that “phase space” of Eric Verlinde is the normal space in which entire astral world resides. Dark energy and Dark matter are the constituent blocks of astral world on the same pattern as our physical world is built of normal energy and luminous matter.

    Such sages and meta physicists who have described the astral world have not given their description based upon mere theoretical speculation but based upon their own subjective experiences. Now it is up to a person whether to trust their experiences or not. There is not much likelihood that present technological advancement of Science may be capable of peeping into astral world in near future.

    On overall basis, astral world and physical world are insulated from each other implying non-interacting. However,since physical world emerges out from astral world and both are infinitesimal closer to each other, “phase space”, dark energy and dark matter, which are the normal space, energy and matter of which astral world is built of, influence space, matter and energy of physical world in many ways.

    Counterpart to physical body of human beings in this physical world, there is astral body (Sukshma Sharir) which, during life, resides in the physical body and after death leaves and resides in astral world

    Link to this
  8. 8. Dredd 4:34 pm 06/12/2012

    “String theorists and other would-be unifiers of physics face a basic problem. The theories they seek to unify, quantum field theory and Einstein’s general theory of relativity, are well-grounded and well-tested, yet mutually incompatible. Reconciling them will demand that some deeply held intuition must give way.”

    A compulsion to unify evinces an insecurity.

    Let the universe be “divided” if that is what it really is, or use what ever word you want to use for “disunity.”

    Do not try to fit the square peg into the round hole.

    Otherwise, we sink deeper into the quicksand of faith and trust, not science.

    http://blogdredd.blogspot.com/2012/01/heretics-deny-dark-matter-of-faith-3.html

    Link to this
  9. 9. Torbjörn Larsson, OM 5:02 pm 06/12/2012

    I’m a happy amateur (with a PhD in electronics, so some physics), yet I find it difficult to shortly list all of the problems I find in this. But let me try:

    - ” quantum field theory and Einstein’s general theory of relativity, are well-grounded and well-tested, yet mutually incompatible.”

    Often said, never defined in a testable way.

    Since general relativity can perfectly well be quantized, but it happens to unurpisingly break down at larger energies perfectly consistent with that GR is known to be effective, is there really an “incompatibility”? Or is simply GR not complete, as “effective” explicitly states?

    - “Participants at the Kavli workshop were inclined to think that space and time are not fundamental, but emergent.”

    Well, yes, as everyone familiar with special relativity emergent spacetime out of space and time.

    - “thermodynamics is the branch of physics that describes composite systems”.

    Which comes as a surprise to those who have studied classical thermodynamics before deepening it with statistical physics.

    Thermodynamics is considered to be as fundamental, if not more, than QM in physics.

    - “gorilla.

    But the room was dust particles at the time the invisible gorilla of atoms were accepted from Einstein’s unambigious predictions and test of Brownian motion.

    Dark matter is better unambiguously observed already after mere years of gravity lensing and other experiments. If atoms were acceptable gorillas well before we could recently visualize them in ion traps, so are DM.

    - “The leading alternative to dark matter is known as MOND”.

    Please! MOND is rejected by most all, what I know of. The same MOND can’t predict observations of DM in different galactic cluster collisions.

    The hold out was _only_ galaxies, while DM was used for structure formation from universal scale down to the first stars. But recently the Eris simulation came out and modeled (spiral) galaxies self-consistently for the first time. Oh, and the missing factor for consistency turned out to be – dark matter.

    - “explain dark matter and dark energy as signatures of a deeper reality, rather than a bolt-on to current theories.”

    They stand for themselves, but they are also not bolt-ons but part of the self consistent standard cosmology.

    Inflation is not yet tested to 3 sigma as is, so that may be more of a point against it.

    After all this nitpicking, is there anything left? Well, I like Verlinde’s description of spacetime “melt” in black holes. Point well taken.

    Link to this
  10. 10. Torbjörn Larsson, OM 5:08 pm 06/12/2012

    Oh, I forgot. The Planck 1st data release is due this year. It should sufficiently test inflation by its lonesome, which should complicate “dislike” since competitors aren’t even tested I believe.

    Link to this
  11. 11. cerberushowls 6:00 pm 06/12/2012

    oh, pish posh, jtdwyer. all of you rotational and gravitational knowledge is equivalent to that of a middling beagle. How can you explain my sisters conjoined twin making big ducats on the internet with nothing but a 9600 baud modem? Schrodinger’s Cat got your tongue? Ha, there’s science for you…

    Link to this
  12. 12. bigb1975 7:51 pm 06/12/2012

    Love reading anything about dark matter..Great read this..

    http://www.freeinventions.info/

    Link to this
  13. 13. rloldershaw 11:33 am 06/13/2012

    George Musser asks: ‘If Verlinde is wrong, where have we gone wrong in our other assumptions?’

    Here are 3 quick suggestions for which fundamental assumptions are holding physics back.

    1. First and foremost at the beginning of the 1900s physicists assumed that the Newtonian gravitational constant is absolutely the same on all scales of nature’s hierarchy. In a discrete fractal or conformal model of nature, this assumption fails badly. The value of G within an atom or subatomic particle has never been measured; it is purely assumed to be the conventional value. If G changes by large and discrete amounts for each cosmological scale [atomic, stellar, galactic], as predicted by Discrete Scale Relativity, then you get a whole new paradigm for understanding the structure and dynamics of nature.

    2. We have assumed that strict reductionism is the “only game in town”. This is a bad assumption and flagrantly ignores the clear fractal and conformal properties of nature.

    3. Physics has suffered because of its inability to bring the fundamental symmetry: relativity of scale, into its theories. It has been wrongly assumed that scale is absolute. This is probably false and very misleading.
    Weyl, Einstein, Dirac and a host of others tried repeatedly to work relativity of scale into physics, but it never seemed to work quite right.

    However, if your emphasis is on studying nature, instead of studying Platonic models, then you can see how nature accomplishes this.

    Nature cannot have continuous conformal symmetry because that strongly violates our empirical knowledge of nature.
    But discrete conformal symmetry does not need to conflict with empirical results.

    If the laws of physics, especially gravitation, are recast with discrete conformal symmetry, then you get a new and completely different understanding of nature in terms of a discrete self-similar hierarchy that has no bounds.

    With this new paradigm you can unify GR and QM, explain the fine structure constant, demystify h-bar, resolve the vacuum energy density crisis, predict the exact nature of the dark matter, retrodict the masses of all particles (including the electron), and have a proper understanding of the hierarchy of Planck scales.

    This new paradigm predicted pulsar-planets, and it predicted the hundreds of billions of unbound planetary-mass objects recently inferred as roaming free throughout the Galaxy. It makes an exact prediction for the dark matter mass spectrum.

    I have a website that serves as a teaching resource for this new paradigm.

    RLO
    http://www3.amherst.edu/~rloldershaw
    Discrete Scale Relativity
    Fractal Cosmology

    Link to this
  14. 14. Zephir 7:59 am 06/14/2012

    In dense aether model the above green illustration of dark matter with the water surface could be a more consequential. It corresponds the situation, when the surface ripples are scattered into (hidden dimensions of) underwater at distance. When we would observe the water surface with its own ripples, then the fuzzy density fluctuations of underwater will be the last observable reality, which we could observe until all ripples will scatter into it. The dark matter therefore correspond the observation of the outer surface of out Universe, where the spatial and temporal dimensions alternated their role.

    After all, what the “emergent space-time” concept actually means? Without dense particle system this concept has no physical meaning and we cannot imagine anything about it.

    But when we adopt the water surface analogy, then the deDuillier/LeSage model of gravity would become suddenly more relevant and much more straightforward, than the entropic gravity. In LeSage analogy of water surface the gravity would be generated with shielding of underwater waves by massive objects. These underwater waves correspond the gravitational waves and the surface ripples correspond the waves of light. After then it’s apparent, these underwater waves must be way faster than the surface ones and the whole analogy will change into the ancient model of gravity based on the shielding of ultramundanne particles, i.e. the tachyons.

    Link to this
  15. 15. Zephir 10:05 am 06/14/2012

    In dense aether model the above green illustration of dark matter with the water surface could be a more consequential. It corresponds the situation, when the surface ripples are scattered into (hidden dimensions of) underwater at distance. When we would observe the water surface with its own ripples, then the fuzzy density fluctuations of underwater will be the last observable reality, which we could observe until all ripples will scatter into it. The dark matter therefore correspond the observation of the outer surface of out Universe, where the spatial and temporal dimensions alternated their role.

    After all, what the “emergent space-time” concept actually means? Without dense particle system this concept has no physical meaning and we cannot imagine anything about it.

    But when we adopt the water surface analogy, then the deDuillier/LeSage model of gravity would become suddenly more relevant and much more straightforward, than the entropic gravity. In LeSage analogy of water surface the gravity would be generated with shielding of underwater waves by massive objects. These underwater waves correspond the gravitational waves and the surface ripples correspond the waves of light. After then it’s apparent, these underwater waves must be way faster than the surface ones and the whole analogy will change into the ancient model of gravity based on the shielding of ultramundanne particles, i.e. the tachyons.

    Link to this
  16. 16. giovannimirandola 8:48 am 06/15/2012

    Dear Dr Giovanni Mirandola,

    Many thanks for your mail and the interesting ideas. If I understand you
    correctly, you suggest viewing physics from a higher dimension. That may help resolve
    many puzzles. I agree with you. While it is a good possibility, many of the details
    are to be worked out. string theory is one such attempt.

    With best regards,

    Pankaj S. Joshi

    Giovanni Mirandola wrote:
    >
    > I have read with it appeal to its article on the singularities knots, thus I allow myself to send them mias the simple idea dell’ universe. They are not a mathematician, but l’ idea me seems simple and elegant thus, hopes not to have said stupidity, if thus, it will have been made laugh the university professor, and in any case this mail is served to something.
    >
    >
    > L’ universe like three-dimensional surface of an object more dimensions, Turning over the outlines, abandoning “the eliocentrico” outline, we try to imagine l’ universe not like a sphere quarry to three dimensions but like the surface to 3 dimensions of a multidimensional object. The behavior of subatomic particles extradimensional, thus also the gravity. Our universe like the terrestrial surface, the tettonica can be imagined the hot spots, the magma, than of it they determine the form are l equivalent of the dimensions and of the forces that work under our universe they model and it and they characterize to them. Cat of srhodingher is not possible to determine particles () because or they are found to manifest itself in our dimension or the others, if the blocchiamo and we determine we prevent to see of all to them the characteristics, the gravity and solo the three-dimensional manifestation of an event or multidimensional means that operates under the surface dell’ universe. The light travels on the surface of this supersphere giving to us l’ impression to find to us all’ inside while in effects of we are only the surface. Verosimilmente exists a bidimensional truth on the “multidimensional surface” of our three-dimensional universe, and other truths to of under of our three-dimensional truth. The black holes are the tendency of the matter to combine to the space \ time and “to return” to a pluridimensionale space (like a heavier liquid on a surface stretch to sink in the liquid supports that it).
    >
    > Sincerely yours
    >
    > Dott. Giovanni Mirandola
    >
    > Verona Italy
    >
    >
    >
    >

    Pankaj S. Joshi
    Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400005
    Phones: 022-2278 2486 (O) 022-2280 4923; 2278 3486 (R)
    Fax: 091-22-2280 4610/4611
    E-mail: psj@tifr.res.in

    Link to this
  17. 17. anselm 8:50 am 06/15/2012

    Excellent, Jtdwyer & Percival,I bring to your information that ,Dark matter has been seen and photographed by, Lawrence Berkley National Lab/s USA”Clearest Picture Yet of Dark Matter Points the Way to Better Understanding of Dark Energy” , it was a First picture of Dark matter obtained by the relevant teams led by Scientist Eric Duff.I analysed the Documentation and write -ups and it was most interesting, there are several Cosmologist Teams analysing the Data.
    Mr vinodsehgal,I am giving a piece of advice,your Article was perfectly artful ,I have a deep appreciation on its depth,but with a Blot– delete the words “physical world are insulated from each other implying non- interacting,Remember that the Einstien’s Gravitational Equation is still incomplete and the
    Right Hand Side the important “”"TORQUE “”"of Angular Momentum of all CELESTIAL BODIES has not been Mathematically solved, its the missing Link –which must be found to make a explicitly clarity painted breakthrough to unify the Quantum World and Gravitation.
    The Graviton, Monopole,the Moon’s BEADED ORBIT & ROTATION,
    coupling the earth and sun ,in a TUG TORSION SAWTOOTH PATH,is an integral component to interlink& Couple the twoWorlds– Macro and Micro,mysteries.

    Link to this
  18. 18. vinodsehgal1957@yahoo.com 9:14 am 06/16/2012

    To anseim (17)

    By “insulating” of physical and astral worlds, I meant to say that though spatially infinitesimally closer to each other, both the worlds operate normally as per the respective physical laws and non-interfering with each other. E.m. radiation from physical world may not interact with any physical entity of astral world and vice-versa. Similarly living inhabitants of both worlds also do not interfere with each other except some special circumstances. E.m radiations of this physical world, as we know know, are created in this physical world, with the basic cause appearing from the astral world at time of creation of physical world. Big Bang as we know is the creation of the space/time, matter and energy of this physical world, with the basic ingredients appearing from the pre-existing astral world. Since, as on date, E.M radiation is the only means available to scientists to have information, therefore I mentioned that in the near future there is not much likelihood that Physicists may be able to peep into astral world. However, I suspect that both the worlds are gravitationally interacting. If gravity waves are detected, may be Physicists may have a first hand glimpse of the astral world

    Recently, I had the opportunity to go thro the previews of two books — God Theory By Bernard Haisch, noted Quantum Physicist and Bicentrum by Robert Lanza, world renowned authority on stem cells. Both books available at Amazon. Though not exactly same as my views, these scientists have echoed the similar views about deeper reality above this 3 D world.

    If you have details of dark matter studies by Lawrence Berkley Lab, please provide me the link or send details at vinodsehgal1957@yahoo.com

    Link to this
  19. 19. shalayka 8:06 pm 06/18/2012

    So, what exactly defines the boundary between the foam and the current / oceanic bulk at some location, like the surface of the Earth exactly? Surely not something as simple as the “strength” of the gravitational field, framed in terms of energy, like say … 8 joules? An energy conservation feature that disables long distance high-energy DOFs in the absence of strong gravitation sure would be a silly idea.

    Link to this
  20. 20. Daniel Cohen 12:03 am 06/20/2012

    Verlinde’s analysis is easy to read, but hurts your head? Well that does not validate his point-of-view, nor invalidate it.

    I expect that his analysis is incomplete, and must be viewed as speculation. His is pushing the envelope of our knowledge, and inviting us to come and look, too.

    In short, Verlinde’s value to us is this invitation to build a plan for future physics. So we should remember that it is speculation, and enjoy the path he suggests, until we know more about how the reality might be built.

    Link to this
  21. 21. jtdwyer 2:32 pm 06/20/2012

    Percival – Sorry, but you seem to misunderstand completely. I must have failed to adequately explain. In very simple terms, I suggest the the perceived requirement for galactic dark matter was based on the invalid expectation that the rotational velocities of spiral galaxies should diminish at increasing radii, just as the orbital velocities of planets diminish as a function of their distance from the Sun.

    Since the rotational characteristics of spiral galaxies are produced by their vast distribution of system mass, totally unlike the Solar system where 99.86% of total system mass is located within the Sun, spiral galaxies’ simply do not comply with the laws of planetary motion. There was never any need to explain their deviation from the characteristic rotation of planetary systems – no need to invent corrective undetectable dark matter to provide compensatory mass.

    Link to this
  22. 22. jtdwyer 3:03 pm 06/20/2012

    anselm – Thank you for your kind remarks. I found the Berkeley Lab Jan. 9, 2012 press release, “Clearest Picture Yet of Dark Matter Points the Way to Better Understanding of Dark Energy” at http://newscenter.lbl.gov/news-releases/2012/01/09/clearest-view-dark-matter/

    The subject study does not relate to any photographic image of dark matter which would have been most extraordinary indeed. The researchers have produced another ‘more accurate’ large scale mapping of dark matter inferred by very detailed analyses of minute gravitational effects (optical shear – lensing effects), thought to have been produced by a very large scale scaffolding or ‘cosmic web’ of dark matter. These researchers based their independent analyses on data collected by the Sloan Digital Sky Survey project.

    Link to this
  23. 23. jtdwyer 3:09 pm 06/20/2012

    cerberushowls – You’re correct – I’m only an expert information systems analyst. For a very pertinent debate among experts, please see http://www.bctp.uni-bonn.de/events.php?navigation=dmdebate

    Link to this
  24. 24. vinodsehgal1957@yahoo.com 7:27 am 06/23/2012

    jtdwyer and abselm

    Thank you jtdwyer. From the link provided in your comments, I have gone thro Berkley Lab’s article on imaging of dark matter. From the anselm’ comments, I had got the impression that scientists have had a direct photograph of dark matter. But the article states that what they have photographed are the tiny distortion in the image of background galaxies due to forward concentrations of dark matter.

    One thing you might have noticed is that article is using terms dark matter and dark energy interchangebly as if there is no difference between these entities.

    Link to this
  25. 25. anandsr21 2:17 am 07/23/2012

    Torbjörn Larsson

    I am also not a physicist and just a software engineer.
    The problem is not that MOND is wrong. The problem is that it is an Empirical Formula which works very well for all galaxy sized objects. This is a deadly problem for General Relativity. The MOND need not be right, and it is definitely not right, after all it doesn’t even pretend to be a theory. TeVeS is just a toy theory, which was created for the sole purpose of showing that it can be done. It’s probability of being the true picture of the universe is impossibly negligible.

    I hope you know the significance of Emperical Laws in Science. A theory must be consistent with all observations. An Empirical law is a very well defined set of observations. For a theory to be accepted as a valid theory all Empirical Laws must be derivable from the theory.

    The problem with General Relativity is that it has no way to derive MOND. MOND simply kills GR, just by working well for all galaxies.

    To understand Cosmologists situation understand that A man will never understand a point, if his salary depends on not understanding it :-) .

    For cosmologists the problem is if GR does not work in low acceleration regimes as MOND obviously shows, then they are just mucking around in the dark. All the papers they are publishing are not worth the pages they are published on. They will change direction as soon as there is a theory that will derive MOND and is still consistent with all other observational data, so that they can continue to do something and get their salary. That Theory does not exist now.

    I am hoping Verlinde will break this horrible situation.

    BTW The Bullet Cluster has an impossibly high velocity for GR. Also read about Abell520, which is not even possible in GR. Cosmologists have been ignoring the two problems. Obvious conflicts with Bread & Butter.

    Link to this
  26. 26. PleonasticAxiom 6:22 pm 08/4/2012

    I thought bosons were dark matter?
    If bosons give mass, assuming they aren’t equally distributed, If we are passing through an area with a higher concentration of bosons, wouldn’t we accumulate mass? Couldn’t we attribute the red-shift we see to the fact that we are crossing the galactic plane? Kinda like how when you accelerate freakishly fast, your perception changes, you think you’re getting smaller and your destination looks like it’s getting farther away, aka redshift.

    With this thinking, couldn’t you assume that bosons also cause the effect of gravity? If they are running along magnetic fields, they would pass through us as such a rate that it causes disturbances in space-time. Ever had a guiness? You do realise those bubbles are being forced down by fluid dynamics, and not the fact that they are “heavier”.

    Just my thoughts.

    Link to this

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