## Emergence of Spacetime --"Built by Quantum Entanglement"

##### May 27, 2015

"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, a Principal Investigator at the University of Tokyo's Kavli IPMU. "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."

Physicists and mathematicians have long sought a Theory of Everything (ToE) that unifies general relativity and quantum mechanics. General relativity explains gravity and large-scale phenomena such as the dynamics of stars and galaxies in the universe, while quantum mechanics explains microscopic phenomena from the subatomic to molecular scales.

The holographic principle shown in the image below 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.

The Daily Galaxy via University of Tokyo

Irrelevant, unless I can verify the facts or obvious related effects :-)

Posted by: Kotys | May 27, 2015 at 09:42 AM

My personal opinion is that anybody can write anything he wants. But I think that one theory that unifies the general relativity and the quantum mechanics should become the tombstone of physics

Posted by: Vaggelis Talios | May 27, 2015 at 01:48 PM

I agree with the authors of an article in consideration of problems. But It looks like recycling the same ideas, mathematical noodling, and the extension of the war between authorities. The quantum entanglement as conditions on the energy density, is described in the Law of Abandonment Origin, which is inextricably linked to the Law of Aging Photons.

Posted by: Michael-2 | May 29, 2015 at 04:49 AM

Of course, our real world is entangled with our opposite copy mirror universe with infinite accurecy, down to the quantum scale of the Higgs vacuum field.

Posted by: Leo Vuyk | June 01, 2015 at 05:12 AM