When Ms. E.M. sent this article to me, she put it in an email with the header "QE creates gravity." Before I opened the link in the email I have to let the readers of this blogsite know that I had an amusing episode of simply allowing my mind to play with the header itself, for acrostics can often be like trying to solve an algebraic equation if one does not know the context in which they occur(yet another reason, folks, for lazy American English to get with the program, and quit using so many abbreviations). Anyway, back to my amusing episode as I contemplated Ms. E.M.'s email header, "QE creates gravity." Those who know me know I am fascinated by the relationship between physics and finance, as if the two were entwined in some deeper cosmology(and I believe profoundly that they are!). So letting my mind play with an "econophysics" context for Ms. M.'s abbreviation, I came up with "Quantitative Easing Creates gravity," an amusing proposition, as if the sheer mass of money might create a "financial gravity well" sucking dollars into some sort of financial singularity or black hole, from which they would never escape(predictors of "immanent hyper-inflation" and "collapse", take note), a kind of financial equivalent to such physical things, wherein all normal rules and laws of financial behavior are reversed in some sort of bizarre non-linear financal world. Then of course, I settled down to more sane possibilities, and thought "quantum electrodynamics creates gravity," a proposition that surely would have delighted Werner Heisenberg and Wolfgang Pauli. And then I thought, of course, of Einstein and Newton, and Einstein's geometrizing of gravity and commensurate banishment of faster-than-light transfers of information along with Mr. Newton's "spooky action at a distance" (and hence, of Mr. Newton's idea of gravity), and came up with the ultimate "Newtonian" rejoinder, "Quantum entanglement creates gravity." Take that, Albert.
Now that, I thought, was a very intriguing possibility, and, moreover, one that various people have contemplated from time to time. Beneath the link in her email, Ms. E.M. also put the very short and inviting sentence "I intuitively like this paper." So I opened the link:
Now, just for kicks, here are the three(well, four) paragraphs that grabbed my attention:
The holographic principle is widely regarded as an essential feature of a successful Theory of Everything. The holographic principle states that gravity in a three-dimensional volume can be described by quantum mechanics on a two-dimensional surface surrounding the volume. In particular, the three dimensions of the volume should emerge from the two dimensions of the surface. However, understanding the precise mechanics for the emergence of the volume from the surface has been elusive.
Now, Ooguri and his collaborators have found that quantum entanglement is the key to solving this question. Using a quantum theory (that does not include gravity), they showed how to compute energy density, which is a source of gravitational interactions in three dimensions, using quantum entanglement data on the surface. This is analogous to diagnosing conditions inside of your body by looking at X-ray images on two-dimensional sheets. This allowed them to interpret universal properties of quantum entanglement as conditions on the energy density that should be satisfied by any consistent quantum theory of gravity, without actually explicitly including gravity in the theory. The importance of quantum entanglement has been suggested before, but its precise role in emergence of spacetime was not clear until the new paper by Ooguri and collaborators.
Quantum entanglement is a phenomenon whereby quantum states such as spin or polarization of particles at different locations cannot be described independently. Measuring (and hence acting on) one particle must also act on the other, something that Einstein called “spooky action at distance.” The work of Ooguri and collaborators shows that this quantum entanglement generates the extra dimensions of the gravitational theory.
“It was known that quantum entanglement is related to deep issues in the unification of general relativity and quantum mechanics, such as the black hole information paradox and the firewall paradox,” says Hirosi Ooguri. “Our paper sheds new light on the relation between quantum entanglement and the microscopic structure of spacetime by explicit calculations. The interface between quantum gravity and information science is becoming increasingly important for both fields. I myself am collaborating with information scientists to pursue this line of research further.”(Emphasis added)
So, what's going on? Well, let's throw all caution to the winds and indulge in some extreme speculation. We all know how gravity is supposed to work, at least, in the Newtonian sense, namely, that anything with mass exerts an attraction on anything else with mass, and thus, in a simplistic way, everything in the universe is attracted to everything else in the universe, no matter how far apart from each other they are. And now, if this theory be true, then this might be explained by the phenomenon of quantum entanglement, in the form that everything is "quantum entangled" with everything else in some deep way, say this or that electron in your body with another electron on the other side of the galaxy. In the light of yesterday's high octane speculations about memory, what might this imply? Well, for one thing, that there may be a connection between memory and gravity and entanglement. This may not be as bizarre and outlandish as it at first sounds, since it was Albert the Great (Einstein, not Aquinas' mentor) that linked gravity and time in General relativity. Memory is not, of course, mere time in Einstein's sense, because it would appear that memory, unlike Einstein's time, is not a mere scalar. But, if one assumes for the moment that time is not a scalar either, then all sorts of possibilities open up for a kind of macro-and-micro-socio-physical engineering, provided, of course, that one knows the laws connecting information and the macro- and micro-physical scales. And that's going to require, perhaps, rethinking all those standard delta-t (change in time) functions in physics along the lines of sets, combinatorics, tesselations, and so on.
And that's what makes this little article about a new theory so intriguing. And there is, perhaps, a potential hidden implication here, and that is that entanglement might just turn out to be an alternative to dark matter and dark energy and other mathematical artefacts that populate the current theory. Time will tell, but like Ms E.M., I "intuitively like this theory." And for Gabriel Kron fans, for whom electrical machines are complex networks connecting higher dimensional spaces, this theory will have their minds buzzing with even more possibilities.
See you on the flip side...