Invariant class operators in the decoherent histories analysis of timeless quantum theories

This chapter presents experimental studies performed on planar semiconductor microcavities in the strong-coupling regime. The first section reviews linear experiments performed in the 1990s that evidence the linear optical properties of cavity exciton-polaritons. The chapter is then focused on experimental and theoretical studies of resonantly excited microcavity emission. We mainly describe experimental configuations in which stimulated scattering was observed due to formation of a dynamical condensate of polaritons. Pump-probe and cw experiments are described in addition. Dressing of the polariton dispersion and bistability of the polariton system due to inter-condensate interactions are discussed. The semiclassical and the quantum theories of these effects are presented and their results analysed. The potential for realization of devices is also discussed.

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Generalised Kochen–Specker Theorem in Three Dimensions

Foundations of Physics ◽

10.1007/s10701-021-00476-3 ◽

2021 ◽

Vol 51 (3) ◽

Author(s):

Václav Voráček ◽

Mirko Navara

Keyword(s):

Unit Sphere ◽

Hidden Variables ◽

Three Dimensions ◽

Quantum Theories

AbstractWe show that there is no non-constant assignment of zeros and ones to points of a unit sphere in $$\mathbb{R}^3$$ R 3 such that for every three pairwisely orthogonal vectors, an odd number of them is assigned 1. This is a new strengthening of the Bell–Kochen–Specker theorem, which proves the non-existence of hidden variables in quantum theories.

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FREQUENCY OF SEEING FUNCTIONS FOR INTENSITY DISCRIMINATION AT VARIOUS LEVELS OF ADAPTING INTENSITY

The Journal of General Physiology ◽

10.1085/jgp.34.4.463 ◽

1951 ◽

Vol 34 (4) ◽

pp. 463-474 ◽

Cited By ~ 35

Author(s):

Conrad G. Mueller

Keyword(s):

Human Subject ◽

Intensity Discrimination ◽

Quantum Theories ◽

Foveal Stimulation

1. The percentage of times a human subject detects an increment (ΔI) in intensity was determined as a function of the magnitude of the increment and the magnitude of the stimulus (I) to which the increment is added. 2. Foveal stimulation was used, and five frequency of seeing curves were obtained at each of nine values of adapting intensity covering the range from –1.45 to 4.45 log photons. Each frequency of seeing curve shows the percentage of times an increment in intensity is detected as a function of the logarithm of the increment. 3. The slope of the frequency of seeing curve increases slightly with an increase in I and finally becomes independent of I at medium to high intensities. 4. The implications of the results for quantum theories of visual excitation are considered.

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Spin and Dynamics in Relativistic Quantum Theories

Few-Body Systems ◽

10.1007/s00601-014-0920-5 ◽

2014 ◽

Vol 56 (6-9) ◽

pp. 395-399 ◽

Cited By ~ 3

Author(s):

W. N. Polyzou ◽

W. Glöckle ◽

H. Witała

Keyword(s):

Relativistic Quantum ◽

Quantum Theories

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NONCOMMUTATIVE OPEN STRING THEORIES AND THEIR DUALITIES

Modern Physics Letters A ◽

10.1142/s0217732301003450 ◽

2001 ◽

Vol 16 (04n06) ◽

pp. 349-359 ◽

Cited By ~ 1

Author(s):

M. M. SHEIKH-JABBARI

Keyword(s):

Open String ◽

Low Energy ◽

Duality Group ◽

Critical Limit ◽

Quantum Theories ◽

Open Strings ◽

Energy Theory ◽

String Theories

The recently found noncritical open string theories is reviewed. These open strings, noncommutative open string theories (NCOS), arise as consistent quantum theories describing the low energy theory of D-branes in a background electric B-field in the critical limit. Focusing on the D3-brane case, we construct the most general (3+1) NCOS, which is described by four parameters. We study S- and T-dualities of these theories and argue the existence of a U-duality group.

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