Posts Tagged String theory
Which is better for fundamental physics: beautiful mathematics based on pure concepts, or qualitative insights based on natural phenomena?
According to Lee Smolin in a 2015 arxiv paper , it’s the latter.
Mathematical symmetries: More or fewer?
How to find a better physics?
26 February 2016, Christchurch, New Zealand
This is an expansion of a post at Physics Forum https://www.physicsforums.com/threads/smolin-lessons-from-einsteins-discovery.849464/#post-5390859
 1. Smolin, L.: Lessons from Einstein’s 1915 discovery of general relativity. arxiv 1512.07551, 1-14 (2015). doi: http://arxiv.org/abs/1512.07551
A New Scientist article ‘Why space has exactly three dimensions’ by Matthew Chalmers raises the ontological question of why 3-D, as opposed to something else. The article goes on to show that mathematical representations of quantum mechanics work best with three.
Our own Cordus work also provides circumstantial evidence for space having three dimensions. This arises from the requirement for particules to emit discrete forces in three directions.
Our response to the article follows:
Coming at it from a completely different direction, namely applying the design method to a non-local hidden-variable (NLHV) solution, we also find things work out when there are three dimensions to space. In this case explaining string theory is not a big problem, because it happens that we need about the same number of internal variables to define the NLHV design, as are needed in string theory (http://vixra.org/abs/1204.0047). Entanglement and wave-particle duality are readily explained (http://physicsessays.org/doi/abs/10.4006/0836-1398-25.1.132). Obtaining unification of the electro-magneto-gravitational-strong interactions is also conceptually achievable with NLHV solutions (http://dx.doi.org/10.5539/apr.v5n5107). As a plus, it also gives a theory for time, and thereby addresses not only space but spacetime too (accepted, preprint http://vixra.org/abs/1301.0074). (Spoiler: time becomes an emergent property of matter in this theory).
I wouldn’t claim we have really addressed the deeper ontological question of why three dimensions. But we can at least show that three gives a robust and coherent NLHV solution that explains many difficult areas in fundamental physics. See Cordus on vixra for details.
Space vs time: One has to go – but which? This is the question asked by Anil Ananthaswamy at New Scientist asks. As he says, ‘If we want to progress towards a theory of everything, we need to understand how space and time fit together – if they do at all.’ He goes on to review the usual candidates: quantum mechanics and general relativity, and finds them wanting. Then he checks out string theory (and AdS/CFT) and then takes in loop quantum gravity. Ultimately there are no definitive answers. As he concludes, ‘Many potential ways around lead to different worlds of space and time – and we have as yet little clue which route to follow.’
Here’s our take on this subject, being a copy of our post at the NS article:
We have a theory that time is an emergent property of matter, as opposed to being a dimension of its own or a property of space. The idea being that particles of matter emit discrete forces at their de Broglie frequency, and these are meshed together over space to create a fabric of discrete fields. The particles then interact with each other via the discrete field forces that they send to and receive from this fabric, and since those interactions are not instantaneous (for reasons given in the theory), so the arrow of time emerges.
This is an unorthodox perspective, especially since it starts from a non-local hidden-variable (NLHV) solution, but it has the benefit of being able to explain everything that quantum mechanics, general relativity, LQG, and string/M theory can explain about time, and quite a lot more. We call this the Cordus theory. It becomes quite simple to explain why time as measured by atomic clocks is consistent with time as we perceive it as humans, how time dilation occurs, where the arrow (irreversibility) arises, how time began, whether time exists outside an expanding universe, and many other such niggly little questions at fundamental and cosmological levels.
I can’t explain the whole thing in one post – instead I just want to point out that there already are answers for pretty much all the questions raised in the article, providing one is prepared to be open-minded and look beyond the fixed mental models provided by the orthodox theories. According to this Cordus theory there is nothing wrong with QM and GR per se, it is just that they are situationally-accurate but merely special-case approximations of a deeper mechanics. The only reason time is such a quandary to QM and GR is because those theories have premises that limit what kind of solutions can be admitted. But at the deeper level it is easy to unify the forces, resolve wave-particle duality, and explain entanglement and locality. So there is a lot of progress being made in the unorthodox areas of physics, even if the mainstream has stagnated.
Of course we could also be wrong! Make up your own mind: See the full time paper here http://vixra.org/abs/1301.0074 or a simpler series of explanations here https://cordus.wordpress.com/category/time/.
String theory (which is really a broad family of theories) suggests that it is possible to make sense of fundamental physics. But only if there are 11 dimensions in which to operate (or 10, or 26 depending on the version of the theory). Unfortunately it can’t tell us anything about how or where those other extra dimensions exist. Also problematic is that there are innumerably many solutions to the mathematics, and it has not been possible to identify a variant that corresponds to the world we inhabit. So the potential in string theory has never been realised. It is too abstract to provide working models or physical explanations. Physicists are divided about its usefulness: some love it, while others, like Lee Smolin and Peter Woit, are critical of string theory for its speculative nature, lack of testable predictions, and cognitive dominance over physics.
Consequently we have considered string theory generally irrelevant: at least for our purpose of seeking a physically meaningful explanation for physics. However some strange coincidences have caused us to question this position.
Do the Eleven variables for a cordus particule, correspond to the Eleven dimensions for string theory?
We notice that it requires 11 variables to define a cordus particule. These are all features of the geometry, such as the number and orientation of the discrete field elements (HEDs). Strangely, that’s the same number of dimensions in M-theory, one of the popular string theories. Another similarity that string theory predicts that the photon is an open string, and cordus also predicts a photon particule with two free ends.
Two coincidences don’t make a pattern. Nonetheless it raises an interesting possibility:
cordus and string theory might be describing the same thing from different perspectives
It may be that a cordus-type model, or some other model of hidden-internal-variables, is a physical representation of one of the string theories. That’s an interesting thought, because if it were even partly true then it would open up a whole new set of research possibilities.
So what we are suggesting here is that the ‘orthogonal spatial dimensions’ in string theory might correspond to ‘geometric independent-variables’ in a hidden-variable solution. That would also neatly explain where the extra string dimensions go: they simply represent small-scale geometric features at the sub-quantum level.
It is a radical thought, and of course the weak point in our argument is the assumption that dimensions = variables. Is that valid or not? Yes, from the general perspective of maths (and statistics, and engineering dimensional-analysis too), but string theory may have other constraints of which we are unaware. Something for a string theorist to look into? See here for details: http://vixra.org/abs/1204.0047
Seeing a possible connection between string theory and hidden-variable theories has, up to now, not been feasible. This is because hidden-variable theories have been under siege from Bell-type inequalities, and because of a lack of such theories. Having an operational concept like cordus makes the comparison possible.
Perhaps string theory might yet be a tool for the development of physically meaningful explanations for fundamental physics?
- String theory: A beginner’s guide (New Scientist)
- The Trouble With String Theory (io9.com)
- The Trouble With Physics: The Rise of String Theory, The Fall of a Science, and What Comes Next by Lee Smolin
- Not Even Wrong: The Failure of String Theory and the Search for Unity in Physical Law by Peter Woit
- Circumventing Bell’s theorem? (cordus.wordpress.com)
- String theory: The fightback (New Scientist)
- What string theory is really good for (New Scientist)