English
Related papers

Related papers: Paths, negative "probabilities", and the Leggett-G…

200 papers

For more than a century lattice random walks have been employed ubiquitously, both as a theoretical laboratory to develop intuition about more complex stochastic processes and as a tool to interpret a vast array of empirical observations.…

Statistical Mechanics · Physics 2024-12-31 Luca Giuggioli , Seeralan Sarvaharman , Debraj Das , Daniel Marris , Toby Kay

In settings ranging from weather forecasts to political prognostications to financial projections, probability estimates of future binary outcomes often evolve over time. For example, the estimated likelihood of rain on a specific day…

Machine Learning · Computer Science 2021-11-05 Zhiyuan Jerry Lin , Hao Sheng , Sharad Goel

We propose that measurements of time-of-arrival correlations in multi-partite systems can sharply distinguish between different approaches to the time-of-arrival problem. To show this, we construct a Positive-Operator-Valued measure for two…

Quantum Physics · Physics 2017-03-15 Charis Anastopoulos , Ntina Savvidou

The classical notions of continuity and mechanical causality are left in order to refor- mulate the Quantum Theory starting from two principles: I) the intrinsic randomness of quantum process at microphysical level, II) the projective…

Quantum Physics · Physics 2015-05-20 Edgardo T. Garcia Alvarez

Wigner's form of the local realist inequality is used to derive its temporal version for an oscillating two-level system involving two-time joint probabilities. Such an inequality may be regarded as a novel form of the Leggett-Garg…

Quantum Physics · Physics 2015-03-24 Debashis Saha , Shiladitya Mal , Prasanta K. Panigrahi , Dipankar Home

The possibility of observing violations of temporal Bell inequalities, originally proposed by Leggett as a mean of testing the quantum mechanical delocalization of suitably chosen macroscopic bodies, is discussed by taking into account the…

Quantum Physics · Physics 2009-10-31 Tommaso Calarco , Marcello Cini , Roberto Onofrio

Quantum walks constitute important tools in different applications, especially in quantum algorithms. To a great extent their usefulness is due to unusual diffusive features, allowing much faster spreading than their classical counterparts.…

Quantum Physics · Physics 2012-10-09 F. M. Andrade , M. G. E. da Luz

We show that in wavepacket tunnelling localisation of the transmitted particle amounts to a quantum measurement of the delay it experiences in the barrier. With no external degree of freedom involved, the envelope of the wavepacket plays…

Quantum Physics · Physics 2015-05-27 D. Sokolovski , E. Akhmatskaya

Feynman path integrals are now a standard tool in quantum physics and their use in differential geometry leads to new mathematical insights. A logical treatment of quantum phenomena seems to require a sustained mathematical analysis of path…

Mathematical Physics · Physics 2022-04-18 B. R. F. Jefferies

Wave-particle duality in multi-path interference is fraught with issues despite substantial progress in recent years. It was experimentally shown that in certain specific conditions, getting path information in a multi-path experiment can…

Quantum Physics · Physics 2019-10-11 Tabish Qureshi

Tests of local realism and macrorealism have historically been discussed in very similar terms: Leggett-Garg inequalities follow Bell inequalities as necessary conditions for classical behavior. Here, we compare the probability polytopes…

Quantum Physics · Physics 2016-04-22 Lucas Clemente , Johannes Kofler

The before-before experiment demonstrates free will acting from outside space-time. The experimental violation of the Leggett's inequality supports the view that it is not appropriate to attempt to limit this freedom in Nature by forcing it…

Quantum Physics · Physics 2008-01-22 Antoine Suarez

Time delay is ubiquitous in many experimental and real-world situations. It is often unclear whether time delay plays a significant role in observed phenomena, and if it does, how long the time lag really is. This would be invaluable…

Data Analysis, Statistics and Probability · Physics 2025-12-10 Robin A. Kopp , Sabine H. L. Klapp , Deepak Gupta

Feynman's path integral approach is to sum over all possible spatio-temporal paths to reproduce the quantum wave function and the corresponding time evolution, which has enormous potential to reveal quantum processes in classical view.…

In an endeavour to better define the distinction between classical macroscopic and quantum microscopic regimes, the Leggett-Garg inequalities were established as a test of macroscopic-realistic theories, which are commonly thought to be a…

Quantum Physics · Physics 2021-04-14 Hadrien Chevalier , A. J. Paige , Hyukjoon Kwon , M. S. Kim

In the Leggett-Garg approach to testing macrorealism, the two-time correlation functions, which are normally obtained by sequential measurements of a dichotomic variable Q, need to be measured in a non-invasive way in order to exclude…

Quantum Physics · Physics 2016-11-23 J. J. Halliwell

We report on a stringent test of the non-classicality of the motion of a massive quantum particle, which propagates on a discrete lattice. Measuring temporal correlations of the position of single atoms performing a quantum walk, we observe…

Quantum Physics · Physics 2015-02-11 Carsten Robens , Wolfgang Alt , Dieter Meschede , Clive Emary , Andrea Alberti

Although it may seem The Delayed Choice experiments contradict causality and one could construct an experiment which could possibly affect the past, using Many World interpretation we prove it is not possible. We also find a mathematical…

Quantum Physics · Physics 2019-07-16 Dominik Šafránek

The time evolution of a wave function with $N$ time variables through the Feynman picture of quantum mechanics is derived. However, these evolutions will be compatible if and only if the $N$ Lagrangians satisfy a certain relation called the…

Quantum Physics · Physics 2022-03-09 Siwaporn Sungted , Sikarin Yoo-Kong

In time-series analysis, the term "lead-lag effect" is used to describe a delayed effect on a given time series caused by another time series. lead-lag effects are ubiquitous in practice and are specifically critical in formulating…

Statistical Finance · Quantitative Finance 2020-02-04 Katsuya Ito , Kei Nakagawa