2010-09-03

Testing the Theory of Everything

Researchers Devise the First Experimental Test of Controversial, Confusing String Theory | Popular Science



Is everything in the universe made up of vibrating one-dimensional strings? For the first time, scientists think they can concretely test string theory, the mind-blowing “theory of everything” that has dominated physics for the past two decades. It turns out that string theory predicts the behavior of entangled quantum particles, which can be tested in a lab — therefore testing string theory.


New study suggests researchers can now test the 'theory of everything'


Professor Michael Duff FRS, lead author of the new study. Credit: Imperial College London

(PhysOrg.com) -- Researchers describe how to carry out the first experimental test of string theory in a paper published tomorrow in Physical Review Letters.

String theory was originally developed to describe the fundamental particles and forces that make up our universe. The new research, led by a team from Imperial College London, describes the unexpected discovery that string theory also seems to predict the behaviour of entangled quantum particles. As this prediction can be tested in the laboratory, researchers can now test string theory.

String theory - Wikipedia, the free encyclopedia

String theory is a developing theory in particle physics which attempts to reconcile quantum mechanics and general relativity.[1]
String theory posits that the electrons and quarks within an atom are not 0-dimensional objects, but rather 1-dimensional oscillating lines ("strings"), possessing only the dimension of length, but not height or width. The theory poses that these strings can vibrate, thus giving the observed particles their flavor, charge, mass and spin.


Levels of magnification:
1. Macroscopic level - Matter
2. Molecular level
3. Atomic level -- Protons, neutrons, and electrons
4. Subatomic level -- Electron
5. Subatomic level - Quarks
6. String level


However, prominent physicists such as Richard Feynman and Sheldon Lee Glashow have criticized string theory for not providing any quantitative experimental predictions.[7][8] Like any other quantum theory of gravity, it is widely believed that testing the theory directly would require prohibitively expensive feats of engineering.


Quantum entanglement - Wikipedia, the free encyclopedia


Quantum entanglement, also called the quantum non-local connection, is a property of the quantum mechanical state of a system containing two or more objects, where the objects that make up the system are linked in a way such that one cannot adequately describe the quantum state of a constituent of the system without full mention of its counterparts, even if the individual objects are spatially separated.


Researchers discover how to conduct first test of ‘untestable’ string theory


Professor Duff and his colleagues realised that the mathematical description of the pattern of entanglement between three qubits resembles the mathematical description, in string theory, of a particular class of black holes. Thus, by combining their knowledge of two of the strangest phenomena in the universe, black holes and quantum entanglement, they realised they could use string theory to produce a prediction that could be tested. Using the string theory mathematics that describes black holes, they predicted the pattern of entanglement that will occur when four qubits are entangled with one another. (The answer to this problem has not been calculated before.) Although it is technically difficult to do, the pattern of entanglement between four entangled qubits could be measured in the laboratory and the accuracy of this prediction tested.

“Four-qubit entanglement from string theory.” Physical Review Letters 2010

Corresponding authors: Professor M. J. Duff FRS, Imperial College London.
Co-authors: L. Borsten, D. Dahanayke , W. Rubens (Imperial College London), A. Marrani (Stanford University)

Download a copy of the study using this link: https://fileexchange.imperial.ac.uk/files/6b579a6086/1005.4915v2.pdf