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Updated: Jun 3, 2026

A Photonic System for Generating Unconditional Polarization-Entangled Photons Based on Multiple Quantum Interference
Published on: September 5, 2019
Photonic measurement of apparent presence of spirit using a computer automated system
1Laboratory for Advances in Consciousness and Health, Department of Psychology, University of Arizona, Tucson, AZ, USA. gschwart@u.arizona.edu
Background:
Research investigating the potential of detecting the purported presence of spirit (POS) has been hampered by the necessity of employing a human being to collect the data. To infer the presence of alleged spirit, it is essential to remove the simultaneous presence of an experimenter (POE), thereby eliminating his or her physical energy as well as accompanying conscious intentions and expectations.
Objective:
The purpose of these two proof of concept experiments was to explore the feasibility of completely automating data collection in the absence of an experimenter to determine if evidence consistent with POS was still obtained.
Design:
A computer automated system was developed making it possible to collect all data in the absence of an experimenter (thereby achieving complete experimenter blinding). In the evenings, the computer would perform as follows: (1) start the experimental run at random times, (2) conduct 30-minute baseline as well as POS trials involving two different alleged spirits, and (3) record background light in a completely dark chamber with a highly sensitive low-light Princeton Instruments charge-coupled device (CCD) camera system.
Setting:
The CCD camera and light-tight recording chamber were housed in a light-tight room; the computer, large screen monitor, and speakers were housed in a separate control room.
Participants:
The participants were two purported spirits involved in previous research published in this journal, in which a silicon photomultiplier system was used.
Intervention:
The primary intervention was the computer selecting and presenting visual and auditory information inviting Spirit 1 or Spirit 2 to enter the chamber in the absence of experimenter presence and awareness.
Main Outcome Measurements:
The CCD camera provided 512 × 512 pixel images of 30-minute exposures (reflecting a combination of possible background light plus instrument dark noise). The images were imported into image processing software, and two-dimensional fast fourier transform (FFT) analyses were performed. Visual examinations of the FFT images were performed; average brightness levels of the FFTs were calculated and subjected to repeated measures analyses of variance.
Results:
Compared with prebaseline and postbaseline images, the POS trials were associated with reliable increases in the average brightness of the FFT images, suggesting increased structure of the background light as revealed in the FFTs.
Conclusion:
These findings indicate that POE per se is not sufficient to explain the observed POS effects. Future experiments can address the remaining potential psi interpretations (decision augmentation theory [DAT] and retro psychokinesis [PK]) as well as the source of the observed information (ie, the chamber, cosmic rays, and/or the CCD chip itself).
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