An experiment we conducted from 2012 to 2013, which had not been previously reported, was designed to explore possible psychophysical effects resulting from the interaction of a human mind with a quantum system. Participants focused their attention toward or away from the slits in a double-slit optical system to see if the interference pattern would be affected. Data were collected from 25 people in individual half-hour sessions; each person repeated the test ten times for a total of 250 planned sessions. “Sham” sessions designed to mimic the experimental sessions without observers present were run immediately before and after as controls. Based on the planned analysis, no evidence for a psychophysical effect was found. Because this experiment differed in two essential ways from similar, previously reported double-slit experiments, two exploratory analyses were developed, one based on a simple spectral analysis of the interference pattern and the other based on fringe visibility. For the experimental data, the outcome supported a pattern of results predicted by a causal psychophysical effect, with the spectral metric resulting in a 3.4 sigma effect (p = 0.0003), and the fringe visibility metric resulting in 7 of 22 fringes tested above 2.3 sigma after adjustment for type I error inflation, with one of those fringes at 4.3 sigma above chance (p = 0.00001). The same analyses applied to the sham data showed uniformly null outcomes. Other analyses exploring the potential that these results were due to mundane artifacts, such as fluctuations in temperature or vibration, showed no evidence of such influences. Future studies using the same protocols and analytical methods will be required to determine if these exploratory results are idiosyncratic or reflect a genuine psychophysical influence.
An experiment we conducted from 2012 to 2013, which had not been previously reported, was designed to explore possible psychophysical effects resulting from the interaction of a human mind with a quantum system. Participants focused their attention toward or away from the slits in a double-slit optical system to see if the interference pattern would be affected. Data were collected from 25 people in individual half-hour sessions; each person repeated the test ten times for a total of 250 planned sessions. “Sham” sessions designed to mimic the experimental sessions without observers present were run immediately before and after as controls. Based on the planned analysis, no evidence for a psychophysical effect was found. Because this experiment differed in two essential ways from similar, previously reported double-slit experiments, two exploratory analyses were developed, one based on a simple spectral analysis of the interference pattern and the other based on fringe visibility. For the experimental data, the outcome supported a pattern of results predicted by a causal psychophysical effect, with the spectral metric resulting in a 3.4 sigma effect (p = 0.0003), and the fringe visibility metric resulting in 7 of 22 fringes tested above 2.3 sigma after adjustment for type I error inflation, with one of those fringes at 4.3 sigma above chance (p = 0.00001). The same analyses applied to the sham data showed uniformly null outcomes. Other analyses exploring the potential that these results were due to mundane artifacts, such as fluctuations in temperature or vibration, showed no evidence of such influences. Future studies using the same protocols and analytical methods will be required to determine if these exploratory results are idiosyncratic or reflect a genuine psychophysical influence.
An experiment was conducted to explore possible psychophysical influences on interference patterns generated by an optical double-slit system. The experiment was motivated by a proposed explanation of the quantum measurement problem by John von Neumann and others, namely that consciousness collapses the quantum wavefunction. The study design generated a single database partitioned into eight differential tests, four in experimental conditions where participants alternately directed their attention toward and away from the optical system, and four in sham conditions when no one was present. The planned analysis was comparison of means in attention-toward vs. attention-away conditions; a secondary analysis added later, but before the data were examined, was comparison of variances. After adjusting the eight mean comparisons for multiple testing, none were statistically significant, but one of the eight variance differences was suggestively significant.To date, 11 of 28 conceptual replications of this experiment, reported by four independent teams, have reported statistically significant outcomes (p < 0.05, two-tail), where only one would be expected by chance. Given the implications of psychophysical effects on our understanding of the role of consciousness in the physical world, we encourage others to attempt to replicate this experiment.
Objective: A two-year online experiment tested the hypothesis that focused human attention alternatively directed toward or away from a double-slit optical system would affect the interference pattern in a predictable, unidirectional fashion. A control condition was employed by having a web server periodically simulate a human observer. Method: Based on the results of an independent reanalysis of these data and the outcome of an independent conceptual replication, we revisited the original directional hypothesis to explore the possibility that mind-wandering and other distractions might have caused attention or intention to unpredictably fluctuate. That in turn might have caused the hypothesized psychophysical influence to be more readily detected as a bidirectional effect (i.e., a shift in variance) rather than as unidirectional effect (a shift in mean). To test this idea, we developed a variance-based analysis using data collected during the first year of the experiment and applied it to data from the second year. Results: The first year’s data showed that experimental sessions conducted by humans resulted in significant variance differences as compared to control sessions conducted by a computer, z = 4.16, p = .00002. The same analysis applied to the second year’s data resulted in z = 3.14, p = .0008. Examination of environmental and apparatus variables indicated that those factors were not responsible for the observed changes in variance. Conclusion: The results suggest that a variance analysis may be more sensitive to psychophysical effects in this type of experiment.
Previously reported experiments suggested that interference patterns generated by a double-slit optical system were perturbed by a psychophysical (i.e., mind-matter) interaction. Three new experiments were conducted to further investigate this phenomenon. The first study con- sisted of 50 half-hour test sessions where participants concentrated their attention-toward or -away from a double-slit system located 3 m away. The spectral magnitude and phase associated with the double-slit component of the interference pattern were compared between the two attention condi- tions, and the combined results provided evidence for an interaction (effect size ¼� 0.73 6 0.14, p ¼ 2.4 � 10 � 7 ). One hundred control sessions using the same equipment, protocol and analysis, but without participants present, showed no effect (effect size ¼ 0.04 6 0.10, p ¼ 0.71). A Fraunhofer diffraction model was used to explore various interpretations of this outcome. This analysis suggested that the distribution of light between the two slits and the horizontal stability of the laser beam were the principle components of the optical system that were perturbed. The sec- ond experiment used a duplicate double-slit system and similar test protocol, but it was conducted over the Internet by streaming data to participants' web browsers. Some 685 people from six conti- nents contributed 2089 experimental sessions. Results were similar to those observed in the first experiment, but smaller in magnitude (effect size ¼� 0.09 6 0.02, p ¼ 2.6 � 10 � 6 ). Data from 2303 control sessions, conducted automatically every 2 h using the same equipment but without observ- ers showed no effect (effect size ¼� 0.01 6 0.02, p ¼ 0.61). Distance between participants and the optical system, ranging from 1 km to 18,000 km, showed no correlation with experimental effect size. The third experiment used a newly designed double-slit system, a revised test protocol, and a simpler method of statistical analysis. Twenty sessions contributed by 10 participants successfully replicated the interaction effect observed in the first two studies (effect size ¼� 0.62 6 0.22, p ¼ 0.006). V C 2013 Physics Essays Publication .( http://dx.doi.org/10.4006/0836-1398-26.4.553) Resume´: Des experiences realisees precedemment suggerent que des franges d'interferences generees par un systeme de double fente optique peuvent etre perturbees par des interactions psycho-physiques (c'est-a `-dire des interactions entre conscience et matiere). Trois nouvelles expe ´- riences ont emenees pour etudier ce phenomene. Dans la premiere e au cours de 50 seances d'une demi heure chacune, des participants ont concentreleurs attentions soit pour influencer un systeme de double fente situee a` 3 m de distance, soit pour ignorer ce meme systeme. L'ampleur et la phase spectrale associee aux franges d'interference ont ecompares entre les deux conditions de focalisation de l'attention, et les resultats combines sont compatibles avec l'hypothese d'une inter- action entre conscience et matiere (taille d'effet ¼� 0.73 6 0.14, p ¼ 2.4 � 10 � 7 ). De plus, l'effet n'est pas present quand la meme analyse est effectuee sur cents sessions controles utilisant le meme equipement et le meme protocole, mais fonctionnant en l'absence de participants (taille d'effet ¼ 0.04 6 0.10, p ¼ 0.71). Un modele de diffraction de Fraunhofer utilisepour explorer dif- ferentes interpretations de ce resultat suggere que la distribution de la lumiere entre les deux fentes et la stabilitehorizontale du faisceau laser sont les principaux composants du systeme optique qui ont eperturbes. La seconde experience utilise un systeme de double fente et un protocole de test similaire, mais elle a etemenee sur Internet en envoyant en temps reel les donnees du systeme de double fente aux navigateurs Web des participants. 685 personnes provenant de six continents ont contribue ´ 2089 sessions experimentales. Les resultats sont similaires ala premiere experience mais la taille d'effet est de plus faible amplitude (taille d'effet ¼� 0.09 6 0.02, p ¼ 2.6 � 10 � 6 ). Les don- nees de 2303 sessions de controle, realiseautomatiquement toutes les deux heures en utilisant le meme e mais sans observateurs n'ont montreaucun effet (taille d'effet ¼� 0.01 6 0.02, p ¼ 0.61). La distance entre les participants et le systeme optique, qui va de 1 km a ` 18,000 km, n'est pas correlee avec la taille de l'effet experimental. La troisieme experience utilise un systeme
To investigate von Neumann’s proposal that an “extra-physical process” is involved in the measurement of a quantum system, an online experiment was conducted using a double-slit optical system. In a counterbalanced fashion, participants focused their attention toward or away from a feedback signal linked in real-time to the double-slit component of an interference pattern. A line camera continuously recorded the interference pattern at 4 Hz, and for each camera image fringe visibility was determined for the central 20 fringes. During 2013 and 2014, a total of 1,479 people from 77 countries contributed 2,985 test sessions. Over the same period 5,738 sessions were run as controls by a computer programmed to simulate human participants. The results showed that with human observers the fringe visibility at the center of the interference pattern deviated from a null effect by 5.72 sigma (p = 1.05×10), with the direction of the deviation conforming to the observers’ intentions. The same analysis applied to the control data resulted in an overall deviation of -0.17 sigma. After consideration of alternative explanations, these results were found to support von Neumann’s conclusion that the mind of the observer is an inextricable part of the measurement process. This type of experiment offers a means of empirically resolving longstanding questions about the role of consciousness in the physical world. Resume: Pour examiner si le concept de von Neumann en mecanique quantique d'une interaction de nature « non-physique » est mieux interpretee comme une forme passive d'observation ou comme une influence active, une experience a ete menee sur Internet en utilisant un systeme optique a double fente. Dans un protocole contrebalance, les participants ont concentre ou non leurs attentions sur un signal representant en temps reel le niveau d’interference du systeme de double fente. Une camera enregistrait en continu le motif d'interference a 4 Hz, et pour chaque image, la visibilite d’interference des 20 franges d’interference centrales a ete calculee. Au cours des annees 2013 et 2014, 1479 personnes en provenance de 77 pays ont contribue 2985 sessions. Au cours de la meme periode 5738 sessions controles ont ete enregistrees par un ordinateur qui simulait un participant humain. Les resultats ont montre que la visibilite d'interference pendant les periodes de concentration
A double-slit optical system was used to test the possible role of consciousness in the collapse of the quantum wavefunction. The ratio of the interference pattern's double-slit spectral power to its single-slit spectral power was predicted to decrease when attention was focused toward the double slit as compared to away from it. Each test session consisted of 40 counterbalanced attention-toward and attention-away epochs, where each epoch lasted between 15 and 30 s. Data contributed by 137 people in six experiments, involving a total of 250 test sessions, indicate that on average the spectral ratio decreased as predicted (z=-4:36, p=6*10-6). Another 250 control sessions conducted without observers present tested hardware, software, and analytical procedures for potential artifacts; none were identified (z=0:43, p=0:67). Variables including temperature, vibration, and signal drift were also tested, and no spurious influences were identified. By contrast, factors associated with consciousness, such as meditation experience, electrocortical markers of focused attention, and psychological factors including openness and absorption, significantly correlated in predicted ways with perturbations in the double-slit interference pattern. The results appear to be consistent with a consciousness-related interpretation of the quantum measurement problem.
Lay Summary Whether and how consciousness could affect a physical system is a fundamental question. Radin et al (Radin et al 2012, 2013) reported that consciousness could perturb the fringe pattern of the classical experiment of double-slit illuminated by a laser beam. In understanding the possible physical cause to the observed change of the fringe, Radin et al modeled that the light intensity passing a slit subjected to consciousness intention could have changed. By using computer simulation based on standard wave approaches to light, we demonstrate that the extent of the change to the double-slit fringe as reported by Radin et al can be caused by a spectral perturbation to the light, which would take only approximately times of the energy change pertinent to the intensity change as was modeled by Radin et al. This indicates that the intensity change as modeled was unlikely the physical precursor to the observed effect. Scientific Abstract Significance: Recent reports [Radin 2012, Radin 2013] on variations to the fringe visibility of the interference patterns of laser-engaged double-slit experiments that seemed inexplicable at the absence of psychophysical influences have elicited notable debates within the scientific community and substantial interest in the lay population. In accounting for the observed changes of fringe pattern, Radin et al. modeled that the electrical field of the light passing the two slits might have reached an asymmetry of 3:1 in comparison to the generally symmetric baseline. However, a change to the double-slit interference fringe could have multiple causes. Identifying the most plausible cause to the fringe-pattern changes as were reported is fundamental to the understanding of the nature of psychophysical effect should it exist. Aim: To theorize an alternative interpretation to the fringe pattern changes of the double-slit interference that could be substantially more plausible than the one conjectured by Radin et al. Approach: We implement computer simulations of double-slit fringe pattern based on the Huygens-Fresnel principle using the primary experimental geometrical parameters of Radin et al. to assess how an asymmetry of the double-slit configuration could affect the fringe visibility. Specifically, we assess how an asymmetry in the physical size properties (slit-width and the lateral offset of the slit-center) and the photonic/spectral properties (intensity, wavelength, and spectral bandwidth) between the two slits would affect the fringe pattern. Fourier transformation of the double-slit interference fringe is also conducted when prompted to infer differences between fringe patterns that may be grossly equivocal in terms of the fringe visibility. Results: The main result is that the normalized interference fringe corresponding to the asymmetry of the electrical field of 3/1 or 1/3:1 is grossly indifferent from that caused by an asymmetry of the spectral bandwidth of 0.00205nm between the two slits at 6328nm center wavelength. A spectral broadening of 0.00205nm centered at 632.8nm would take approximately times of the energy of reducing the electrical field of light of that slit to 1/3 to reach a 3:1 inter-slit ratio of the electrical field. This 0.00205nm spectral broadening of the light could be associated with an energy change of no more than 10 picowatts for the experimental setting utilized by Radin et al. Conclusions: A change to the fringe pattern in the double-slit of Radin et al that was fitted with a 3:1 asymmetry of the electrical field between the two slits could be modeled alternatively by an asymmetry of ~0.00205nm in the spectral bandwidth between the two slits. The latter one, which would take approximately times of the energy-change of the former one to happen, could be substantially more plausible than the former one in acting as the physical precursor to the deviation of the double-slit fringe from the baseline pattern as reported by Radin et al.