Whether or not they succeed in remaking space and time, twistorians and string theorists have already endeared themselves to particle physicists. Even fairly simple particle collisions demand equations containing tens of thousands of terms, which are written using a strategy devised by the famous physicist Richard Feynman in the 1940s. Almost all of those terms end up canceling out, but you don’t know in advance which will cancel, so you have to slog through all of them. An alternative strategy inspired by twistors and strings captures symmetries that Feynman’s approach does not, so it sheds the excess mathematical baggage from the outset. Calculations that math whizzes once gave up on now take just a couple of weeks. “I’m pretty sure Feynman would be quite pleased if he saw what we can do,” says Zvi Bern of the University of California, Los Angeles.
The emerging theory of spacetime is still very tentative and so mathematically dense that even those physicists directly involved admit they can barely follow what is going on. Theorists have yet to explain why, if spacetime is merely a construct, it nonetheless seems so real to us. It must somehow take shape much as life springs from inanimate matter. Whatever the process is, it cannot occur only on subatomic scales, because the concept of size must itself emerge. It should be evident on all scales, everywhere around us, if only we know how to look.
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32 Comments
Add CommentThis is yet another instance where nonsensical speculations promoted by influential theorists fail to make connection with physical reality. There is no shred of observational evidence that what this article tries to sell has any merit whatsoever. Hypotheses that cannot be falsified belong to pseudo-science.
Reply | Report Abuse | Link to thisWhen particles behave like groups of numbers and groups of numbers can be shown to behave like particles& is it still weird to ask if there might be a case for fundamental interactions to be emergent properties of number? More specifically, if it takes a minimum number of bits (literally) to describe a physical property of the early universe (or sub-atomic particle interactions) & where do the math and the physics separate in reality?
Reply | Report Abuse | Link to thisI absolutely agree that hypotheses that cannot be falsified belong to pseudoscience. But is that really the case here? The article claims that this theory allows particle physicists to more efficiently conduct simulations. Presumably these simulations have provide predictive power. If those simulations failed to be useful, that would be a falsification.
Reply | Report Abuse | Link to thisRunning simulations faster may be a more efficient modeling tool in comparison with Feynman diagrams. But this has nothing to do with being able to provide more predictive power. With or without twistors, superstring theories are a long shot away from the grandiose claim of field unification.
Reply | Report Abuse | Link to thisLisa Randall at Harvard is a pretty good particle physicist and a pretty good modeler. I would like to know what she thinks about this..
Reply | Report Abuse | Link to thisIsn't accurate predictive abilities overrated as proof of accurate representation of real physical processes? For example, Ptolemy of Alexandria who was able to mathematically predict the motions of the planets in the sky as if they orbited the Earth. For hundreds of years, his successful formulas were regarded of proof that the planets orbited the Earth.
Reply | Report Abuse | Link to thisMore recently, Newton effectively predicted the motions of planets based on gravitational effects modeled as a product of an imaginary attractive force.
Einstein extended the effects of gravitation modeled as the 'curvature' of spacetime represented by a system of dimensional coordinates.
Arguably, none of these effective gravitational models realistically represents any physical process responsible for producing the observed effects of gravitation: they only mathematically describe the effects produced.
Producing more accurate predictive models based on imaginary strings or other mathematical constructs might be very useful but may not actually describe the real physical processes producing the results predicted.
This thing needs a name. I propose "Twistorstring" for simplicity and I hope Witten likes it. I met Penrose once and he seemed to be a remarkably hunble person so I am glad for him his idea has sprung back to life.
Reply | Report Abuse | Link to thisString “theory” continues to break ground as a model, and certainly helps to understand a number of mechanistic processes. But I think it has yet to come up with the demonstrable evidence to accurately wear the title of theory, which should be reserved for mental constructs that have more undergirding.
Reply | Report Abuse | Link to thisThat said, this is an intriguing step forward in our attempt to draft an initial understanding.
The marriage of twistor theory and super string theory may soon end up in a divorce. The marriage does simplify the math but both theories have their limitations and muddy the waters for a new unification theory.
Reply | Report Abuse | Link to thisMy question is simple. If an observer of an experiment must exist in space/time, as well as the experiment, how can we hope to deduce laws that may function outside the parameter of space/time? How might a platonic observer of a cinematic movie reconcile his observations with the celluloid nature of the movie itself? Are we, in fact, in a movie about ourselves that we cannot step outside of?
Reply | Report Abuse | Link to thisIt seems that an african primitive tribe holds the belief that matter is in its deep constituted by vibrations, some kind of resemblance to issues of string theory. You get surprises in strange places.
Reply | Report Abuse | Link to thisPerhaps if it takes off we should call it 'Stwing Theory'
Reply | Report Abuse | Link to thisAndira - Good points, but I suspect that the difficulty in producing a unified theory reflects how poorly established theories accurately represent actual physical processes. Perhaps too many mathematical liberties have been taken in the pursuit of predictive success, misdirecting our conceptions of reality? Thanks.
Reply | Report Abuse | Link to thisGood question: avoiding circular reasoning is a huge challenge of this line of work. The specific effort I wrote about in my article considers particle scattering experiments and predicts what will come out, given what goes in. Our intuition is that such an experiment occurs within spacetime, but the theory can nonetheless describe the outcome without making explicit reference to space or time.
Reply | Report Abuse | Link to this@jtdwyer, that is like saying, we've been wrong in the past therefore we can never be right. Science is a process of refinement. As we develop better tools and collect better data our models become more refined. A crude model may look very different from the reality we know but the model itself is not describing reality, it is describing the relationship between various data points. Newtonian physics is very accurate and we use it all the time to put satellites in orbit, yet it doesn't describe all physical phenomenon. Relativity is required to explain interactions with massive objects or high velocities. At the same time, it does not invalidate the results of classical mechanics. It helps us understand it's limitations but our satellites don't go spinning off into the ether just because we discovered our model wasn't exactly correct. Science isn't black and white. It is shades of grey. Just because a theory doesn't describe phenomenon in absolute detail doesn't mean it isn't useful. We just need to be aware of the limitations.
Reply | Report Abuse | Link to this"but I suspect that the difficulty in producing a unified theory reflects how poorly established theories accurately represent actual physical processes" no, it reflects the difficulty of recreating the big bang in a lab. Quantum Mechanics and Relatively are very accurate at predicting natural phenomenon. Your statement is like me saying your inability to calculate pi, by hand, to the millionth decimal place proves that you are unable to do addition and subtraction.
Classical Mechanics models gravitation as an imaginary attractive force. General Relativity does not describe a physical force producing the gravitational effect; it only represents the effect that the presence of mass imparts to a system of space-time coordinates. Quantum Mechanics does not support particle mass: matter collapses when a quantum gravitational effect is introduced.
Reply | Report Abuse | Link to thisWhile these models produce useful results simulating specific effects, they obviously do not adequately reflect the physical processes producing those effects. Quantum Mechanics even includes algorithms that do not represent any known physical processes, but are required for the model to produce accurate results.
Since these models do not represent physical processes but merely mimic their results, there is no physical basis for integrating them.
One suggestion: I would recommend referring to these various concepts which have not yet been experimentally tested as "hypotheses" or "concepts" rather than "theories", at least in public.
Reply | Report Abuse | Link to thisWe already have enough trouble in the schools, with people of a certain persuasion claiming that evolution is "just a theory", and creationism is "creation science". As I said, just a suggestion.
I agree with hawkeye. This is dead-on.
Reply | Report Abuse | Link to this@jtdwyer, "Since these models do not represent physical processes but merely mimic their results, there is no physical basis for integrating them." that is really naive. Models by their very nature are physically dissimilar to their subject matter. Obviously the universe is not bits in a computer. The results are the point. If a model accurately predicts a result then the model is accurate within its constraints. The Newtonian model of gravitation makes highly accurate predictions about real world phenomenon. It is ridiculous to claim that it has no physical basis. The question is, what is being modeled? In the case of Newtonian gravitation the model is making predictions about the "force" of gravity. Those numbers can then be inserted into calculations of acceleration and from that we can predict the point in space an object under the influence of gravity will likely be give a certain period of time. It isn't modeling the curvature of space-time. It isn't modeling the Higg's field. It isn't even claiming that the so called "force" represents a real entity like a photon. It is modeling the behaviour of objects and not necessarily the physical processes that give rise to those behaviours. You're complaining because the model isn't doing what you want it to do. We have other models for those things. If models were identical to reality then they wouldn't be models, they would be reality. Is that too confusing?
Reply | Report Abuse | Link to thisSoon enough we will know about Higgs,and if it's not found then all of physics not just string theory will be in a mess until the next Einstein comes along and straighten's things out,and or until string disciples can come up with some kind of real experiment's for a physical proof of their theory's.
Reply | Report Abuse | Link to thisEinstein has been quoted as saying: "To the extent that the laws of mathematics refer to reality, they are not true; and to the extent that they are true, they do not refer to reality." and "I do not deny the importance of math, however, it's just that I think that science should come first! Abstract math seems to be the lubricant for hammering square pegs into round holes." Further: "My point is basically that math should be subordinate to empiricism, and that the current crisis in cosmology has resulted, in no small part, from this role reversal!"
Reply | Report Abuse | Link to thisOne wonders if all this applies to the present case.
Space is a soup of gravitoethertons in varying density of field strength. Space is real neutral matter but exotic neither matter or antimatter. Space dominates and rules our universe. Space is creating gravity by push not pull of masses. Space is ETHER OR DARK ENERGY. Einstein discarded ether but space is the reason why time exists and entropy at any point in space is the energy gradient level rate change integral DQ/T from o to time=t . That is why time dilation and time is purely entropical born phenomena . Do not ever combine time and space in continuum and time is not dimension. This is reality and mathematics must also agree to this before any twistor theory.
Reply | Report Abuse | Link to thisI think everything is made up of something else, infinitly. Thanks
Reply | Report Abuse | Link to thisMy answer is "yes". We are indeed in V3 set of existence-frames (spacetime point: Causal Sets) imbedded in V4 that creates the necessary degree of freedom for motion (time). Existence of this schema in V5 is necessary for causal loops (quantum phenomena- Feynman Diagrams particle physics) that were predicted by Godel and Einsten in their Princeton days. Any dimensions beyond V5 are mathematical only , or,
Reply | Report Abuse | Link to thisbelong in another universe. At 70, that is all I have to say.
The answer is "yes"- it is a 3D movie imbedded in V4 with spacetime frames (Causal Blocks), with the fourth dimension providing the Degree of Freedom for motion(time). The "Outside" is in V5 as the realm of Causal Loops that allow for quantum effects (Feynman interactions with -t and +t ). The granularity spacetime separation of each Causal Block is the Feynman distance as predicted by Uncertainty Principle and observed in experiment. Any dimensions beyond V5 are purely mathematical in "our" universe. After 50 years, at 70, that is all I have to say. Prof. R
Reply | Report Abuse | Link to thisCORRECTION: Causal block seaparation is "Planck Length", not Feynman distance. I regret the typo error. Prof R
Reply | Report Abuse | Link to thisCORRECTION: Causal block seaparation is "Planck Length", not Feynman distance. I regret the typo error. Prof R
Reply | Report Abuse | Link to thisEven though we may brainstorm predictive models based on imaginary strings or other mathematical metaphysics constructs that may not actually describe the real physical processes producing the results predicted it must continue because of our inborn drive to identify our origins and destiny. This is specially so when the real physical reality 'in se' is outside our species perceptual and conceptual resolution capacities. Dr.d
Reply | Report Abuse | Link to thisThe new dimension materializes like a figure in a pop-up book. Yet this conjuring trick produced only a single dimension of highly warped space. Using twister concepts, theorists have now shown how all the dimensions of ordinary space—and even time—can pop out.
Reply | Report Abuse | Link to this(Properly said)
However; my conclusions is that, as we travel through time and space will transforms everything into more dimensions.
Everything in this beautiful Universe was created universally for the benefits and appreciation of the one who can perceive with their senses, including the basic, Fire. Water, Air, Earth. For if not! Why would they turn themselves, in-to beautiful work of art?
There are Billions of secrets and unknown events, taking place around us, where we are not aware off, and probably in a Billions year from now we may be able to understand those facts.
Therefore, we Humans have forgotten that we are build only to receive and transmit at a specific cycles (and everything else is out of our limited territory)
We can go on and on, disputing, analyzing and presuming, but most important of all it is, enjoin and appreciation of this creations.
Are we worthy of such unexplained, unexpected, extraordinary, and marvellous miracles (It appears just as if, something or someone expected our arrival?)
In addition, if all this is possible in this four dimensional Universe, what are the possibility and the looks of a 10-12 dimensional Universe? What beautiful world are we to expect? In addition, what aggregated miraculous existence, would there co-exist.
If you want to give Aristotle the benefit of the doubt, the FIRE, WATER, AIR, EARTH basic elements he discusses will sound more modern if you translate the Greek as ENERGY, LIQUID, GAS, SOLID.
Reply | Report Abuse | Link to thisThis is not nonsensical speculation, all matter possesses these qualities, most people either can't model them or as of yet, not really perceivable simply because we are just now beginning to build the tools to perceive this. However, this has been hypothesized for a very long time, and rediscovered time and time again, and now thanks to Penrose formalized in a language that almost makes sense and agrees.
Reply | Report Abuse | Link to thiswe believe that the universe is made by strings,being the particles just vibrations generated in these strings.then the space time continuos are frequency only one,that are energy packets.then these spacetime continuos are generated by left-right handed symmetry breaking( stronger violation of cp),that lead us to the junction of space and time in 4-dimension spacetime continuos with the time being splitted in two opposite orientations that curve the space,generating the spacetime curvatures that is emmergent of 4-dimensional manifolds with non-smooth structures,the 4-dimensional topology has exotics properties.then the conservation of cp for strong interactions are due to the violation of PT,that implies the torsion of curvatures of spacetimes,implicating in the existence of right -left asymmetry to a supersymmetry of a chiral model.where globally the left-right rotational invariance is conserved and the time has "two dimensions " curving the space in the 4-dimension universe with two opposite torsion.being that particles and antiparticles are transformed one into other through
Reply | Report Abuse | Link to thisof violation of left-right symmetry,then the space time are pulsations only one of particles-antiparticles.this is each particles vibrates in an only one frequency of energy that correspond to a only one spacetime continuum
the twistor theory is very important to explain the closed superstrings and theirs multiples knots that carry infinites curvatures of spacetime(loops)
then the violations of pt generates extradimensions of spacetime and implies in the existence of signals with
velocities greatest than the speed of light in the vaccum
then the violation of pt to the conservation of cp to
stronger interactions are explained by the invariance of lorentz( with the contraction of space and time dilatations observed in the violations of asymmetry
to left-right rotation systems interchangeable one into other-then the speed of light appear to observers in uniform relative motions with constant value-then the inversion pt appear as conserved.and the conservations of pt implies the isotropy to speed of light in the connection of space and time into spacetime continuos.the breakdown of pt implies that c might to be have a constant speed)
then the 4-dimensional topologic geometry to the differents spacetime metrics has exotics strucutures due be mirror reflections of extradimensions of spacetimes.