ER = EPR is a
conjecture
In mathematics, a conjecture is a conclusion or a proposition that is proffered on a tentative basis without proof. Some conjectures, such as the Riemann hypothesis or Fermat's conjecture (now a theorem, proven in 1995 by Andrew Wiles), ha ...
in physics stating that two
entangled particles (a so-called
Einstein–Podolsky–Rosen or EPR pair) are connected by a
wormhole (or Einstein–Rosen bridge)
and is thought by some to be a basis for unifying
general relativity
General relativity, also known as the general theory of relativity, and as Einstein's theory of gravity, is the differential geometry, geometric theory of gravitation published by Albert Einstein in 1915 and is the current description of grav ...
and
quantum mechanics
Quantum mechanics is the fundamental physical Scientific theory, theory that describes the behavior of matter and of light; its unusual characteristics typically occur at and below the scale of atoms. Reprinted, Addison-Wesley, 1989, It is ...
into a
theory of everything
A theory of everything (TOE), final theory, ultimate theory, unified field theory, or master theory is a hypothetical singular, all-encompassing, coherent theoretical physics, theoretical framework of physics that fully explains and links togeth ...
.
Overview
The conjecture was proposed by
Leonard Susskind and
Juan Maldacena in 2013. They proposed that a wormhole (Einstein–Rosen bridge or ER bridge) is equivalent to a pair of maximally
entangled black holes. EPR refers to
quantum entanglement
Quantum entanglement is the phenomenon where the quantum state of each Subatomic particle, particle in a group cannot be described independently of the state of the others, even when the particles are separated by a large distance. The topic o ...
(
EPR paradox).
The symbol is derived from the first letters of the surnames of authors who wrote the first paper on wormholes (
Albert Einstein
Albert Einstein (14 March 187918 April 1955) was a German-born theoretical physicist who is best known for developing the theory of relativity. Einstein also made important contributions to quantum mechanics. His mass–energy equivalence f ...
and
Nathan Rosen) and the first paper on entanglement (Einstein,
Boris Podolsky and Rosen). The two papers were published in 1935, but the authors did not claim any connection between the concepts.
[
]
Conjectured resolution
This is a conjectured resolution to the AMPS firewall paradox. Whether or not there is a firewall depends upon what is thrown into the other distant black hole. However, as the firewall lies inside the event horizon, no external superluminal signalling would be possible.
This conjecture is an extrapolation of the observation by Mark Van Raamsdonk that a maximally extended AdS-Schwarzschild black hole, which is a non-traversable wormhole, is dual to a pair of maximally entangled thermal conformal field theories via the AdS/CFT correspondence.
They backed up their conjecture by showing that the pair production of charged black holes in a background magnetic field
A magnetic field (sometimes called B-field) is a physical field that describes the magnetic influence on moving electric charges, electric currents, and magnetic materials. A moving charge in a magnetic field experiences a force perpendicular ...
leads to entangled black holes, but also, after Wick rotation
In physics, Wick rotation, named after Italian physicist Gian Carlo Wick, is a method of finding a solution to a mathematical problem in Minkowski space from a solution to a related problem in Euclidean space by means of a transformation that sub ...
, to a wormhole.
This conjecture sits uncomfortably with the linearity
In mathematics, the term ''linear'' is used in two distinct senses for two different properties:
* linearity of a '' function'' (or '' mapping'');
* linearity of a '' polynomial''.
An example of a linear function is the function defined by f(x) ...
of quantum mechanics. An entangled state is a linear superposition of separable states. Presumably, separable states are not connected by any wormholes, but yet a superposition of such states is connected by a wormhole.
The authors pushed this conjecture even further by claiming any entangled pair of particles—even particles not ordinarily considered to be black holes, and pairs of particles with different masses or spin, or with charges which aren't opposite—are connected by Planck scale wormholes.
The conjecture leads to a grander conjecture that the geometry of space, time and gravity is determined by entanglement.
References
External links
* Susskind, Leonard
"ER = EPR" or "What's Behind the Horizons of Black Holes?"
Stanford Institute for Theoretical Physics. November. 4, 2014.
{{DEFAULTSORT:ER EPR
Black holes
Conjectures
Quantum gravity
Leonard Susskind