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We study the relationship between the structure and star-formation rate (SFR) of X-ray selected low and moderate luminosity active galactic nuclei (AGNs) in the two Chandra Deep Fields, using Hubble Space Telescope imaging from the Cosmic Assembly Near Infrared Extragalactic Legacy Survey (CANDELS) and deep far-infrared maps from the PEP+GOODS-Herschel survey. We derive detailed distributions of structural parameters and FIR luminosities from carefully constructed control samples of galaxies, which we then compare to those of the AGNs. At z~1, AGNs show slightly diskier light profiles than massive inactive (non-AGN) galaxies, as well as modestly higher levels of gross galaxy disturbance (as measured by visual signatures of interactions and clumpy structure). In contrast, at z~2, AGNs show similar levels of galaxy disturbance as inactive galaxies, but display a red central light enhancement, which may arise due to a more pronounced bulge in AGN hosts or due to extinguished nuclear light. We undertake a number of tests of these alternatives, but our results do not strongly favour one interpretation over the other. The mean SFR and its distribution among AGNs and inactive galaxies are similar at z>1.5. At z<1, however, clear and significant enhancements are seen in the SFRs of AGNs with bulge-dominated light profiles. These trends suggest an evolution in the relation between nuclear activity and host properties with redshift, towards a minor role for mergers and interactions at z>1.5., Comment: 25 pages (double-column), 17 Figures, under review at A&A

We have observed the interference of optical diffraction radiation (ODR) and optical transition radiation (OTR) produced by the interaction of a relativistic electron beam with a micromesh foil and a mirror. The production of forward directed ODR from electrons passing through the holes and wires of the mesh and their separate interactions with backward OTR from the mirror are analyzed with the help of a simulation code. By careful choice of the micromesh properties, mesh-mirror spacing, observation wavelength and filter band pass, the interference of the ODR produced from the unperturbed electrons passing through the open spaces of the mesh and OTR from the mirror are observable above a broad incoherent background from interaction of the heavily scattered electrons passing through the mesh wires. These interferences (ODTRI) are sensitive to the beam divergence and can be used to directly diagnose this parameter. We compare experimental divergence values obtained using ODTRI, conventional OTRI, for the case when front foil scattering is negligible, and computed values obtained from transport code calculations and multiple screen beam size measurements. We obtain good agreement in all cases., Comment: 40 pages 18 Figures. accepted for publication in PRSTAB

As a subject, an observer is fundamentally at rest in a reference frame, and this being at rest allows for measuring the motion of physical objects. Exploring the experience of centrifugal force brings to the fore the natural inclination to see oneself at rest in a reference frame. The discrepancy between the experience of centrifugal force and its lack of fundamental significance in Newton's laws of motion points toward the importance of the observer as a subject in his or her own reference frame, specifically the observer's experience of being at rest in this reference frame. In addition, the observer's being at rest for himself or herself in a reference frame is a central feature of both special and general relativity., Comment: 6 pages; an earlier version of this paper appeared in 1992 in T he Journal of Mind and Behavior, vol. 13, pp. 157-162

A neurophysiological thesis is proposed for thermal sensitivity that accounts for the disorder in physical processes that is fundamental to temperature. There is likely some form of thermal equilibrium rapidly established between thermoreceptors and the external environment local to those thermoreceptors that accounts for gauging the temperature accurately within a certain range., Comment: 4 pages; posted 04-07-1998 on American Physical Society eprint site

The difference between proximal and distal stimuli is discussed and an example of the significance of this difference to physics is pointed out in the area of quantum teleportation. In particular, experimental evidence concerning the relative status of the distal stimulus to the observer points toward the relative nature of spatial orientation of objects. In quantum teleportation, this result indicates that the amount of classical information that needs to be transmitted to support the quantum transfer of information may be greater than is expected when the distal stimulus is assumed, as it ordinarily is, to have an absolute orientation in relation to the observer., Comment: 4 pages, related paper at physics/9909008

It has been shown by Einstein, Podolsky, and Rosen that in quantum mechanics either one of two different wave functions predicting specific values for quantities represented by non-commuting Hermitian operators can characterize the same physical existent, without a physical interaction responsible for which wave function occurs. This result means that one can make predictions regarding mutually exclusive features of a physical existent. It is important to ask whether people have the capacity to make observations of mutually exclusive phenomena. Our everyday experience informs us that a human observer is capable of observing only one set of physical circumstances at a time. Evidence from psychology, though, indicates that people may have the capacity to make observations of mutually exclusive physical phenomena, even though this capacity is not generally recognized. Working independently, Sigmund Freud and William James provided some of this evidence. How the nature of the quantum mechanical wave function is associated with the problem posed by Einstein, Podolsky, and Rosen is addressed at the end of the paper., Comment: 44 pages, minor edits made

Maxwell's equations hold in inertial reference frames in uniform translational motion relative to one another. In conjunction with the Lorentz coordinate transformation equations, the transformation equations for the electric and magnetic field components in these reference frames can be derived. As the derivation of the Lorentz coordinate transformation equations depends on the relativity of simultaneity, and indeed on the argument on the relativity of simultaneity, electromagnetic phenomena indicate that human cognition is involved in the structure and functioning of the physical world., Comment: 7 pages

Bennett et al.'s original article on quantum teleportation did not address explicitly synchronizing the orientation of the local spatial reference frames from and to which teleportaton occurs where the state teleported is spin 1/2 along the z axis. They wrote that only two bits of information need to be conveyed classically where the state to be teleported concerns spin 1/2 along the z axis. That only two bits of information need to be classically conveyed could imply that such synchronization is not needed for it would require more classically conveyed information. A gedankenexperiment is presented regarding the orientation of the local spatial reference frames exploring whether such synchronization is not needed even though it was apparently assumed by Bennett et al. that it was required. It is often assumed that there is an absolute, as opposed to a relative, orientation of objects in space. This assumption should be open to empirical test, especially in view of evidence in psychology that the orientation of objects in space is not absolute., Comment: 6 pages, integration of ideas in paper at physics/9909008 with quantum teleportation, revision contains more background

Research methods and results from physics and psychology are used to explore a question in quantum mechanics. In this investigation, an observer variable is manipulated in an experimental context concerning the trajectory of electrons affected by their movement through a Stern-Gerlach apparatus. The basis in psychology concerning why the observer variable is significant in the experimental context is discussed. This investigation can serve as a prototype for more complicated investigations., Comment: 22 pages, extension of papers by Snyder, Journal of Mind and Behavior, 1993, 14, 145-153 and 1995, 16, 151-171

Einstein's argument on the relativity of simultaneity itself is the first result of the special theory of relativity. The nature of this result is explored, and implications of this result for the structure and functioning of the physical world found in the special theory are discussed., Comment: 80 pages, final draft of paper for Physics Essays, vol. 7, 1994, ps. 297-334, posted on APS site at http://publish.aps.org/eprint/gateway/eplist/aps1997sep01_001

A number of issues related to measurement show that self-consistency is lacking in quantum mechanics as this theory has been generally understood. Each issue is presented as a point in this paper. Each point can be resolved by incorporating a cognitive component in quantum mechanics. Measurement in quantum mechanics involves the meaning of the physical circumstances of the experiment. This meaning is in part independent of what traditionally are considered purely physical considerations., Comment: 9 pages, posted on APS site at http://publish.aps.org/eprint/gateway/eplist/aps1998sep23_001

Irreversibility is often considered to characterize measurements in quantum mechanics. Fundamental problems with this characterization are addressed. First, whether a measurement is made in quantum mechanics is an arbitrary decision on the part of the experimenter concerning how the experimental circumstances are structured. Second, how is irreversibility that occurs in making a measurement explained in terms of a neurophysiological mechanism where a macroscopic measuring instrument is not required in principle to make the measurement, as in macroscopic quantum tunneling? Third, how does irreversibility characterize a negative observation where there is no physical interaction in the measurement process?, Comment: 3 pages, posted on APS site at http://publish.aps.org/eprint/gateway/eplist/aps1998apr20_002

It is argued that there is a connection between the fundamental forces of electromagnetism and gravitation. This connection occurs because of: 1) the fundamental significance of the finite and invariant velocity of light in inertial reference frames in the special theory, and 2) the reliance of the general theory of relativity upon the special theory of relativity locally in spacetime. The connection between the fundamental forces of electromagnetism and gravitation follows immediately from these two points. A brief review is provided of: 1) the role of the finite and invariant velocity of light in inertial reference frames in the special theory, and 2) certain fundamental concepts of the general theory, including its reliance on the special theory locally., Comment: 13 pages, posted on APS site at http://publish.aps.org/eprint/gateway/eplist/aps1997apr14_001

A non-technical argument is presented that there is a link between the mind and the physical world in modern physics. Special relativity, general relativity, quantum mechanics, statistical mechanics, and other areas of physics are explored. Each area is found to support the existence of a link between the mind and the physical world. Research from psychology is also presented indicating that there is a role for the discipline of psychology in delineating the nature of this link., Comment: 42 pages, Tailor Press, edits to increase clarity

In quantum mechanics, it is possible to make observations that affect physical entities without there being a physical interaction between the observer and the physical entity measured. Epstein (1945) and Renninger (1960) discussed this situation, and Renninger called this type of observation a "negative observation." Empirical research on electron shelving supports the possibility of negative observations (Bergquist, Hulet, Itano, and Wineland, 1986; Nagourney, Sandberg, and Dehmelt, 1986; Sauter, Neuhauser, Blatt, and Toschek, 1986). Two scenarios are presented that emphasize the role of human observation in negative observations. The first is modeled after the two hole gedankenexperiments of Feynman, Leighton, and Sands (1965) and portrays negative observations in a non-technical manner. The second scenario allows for quantifying the affect on physical entities of negative observations in a simple fashion. In addition, various issues related to negative observation are discussed, including an objection that might be raised. The Schrodinger cat gedankenexperiment is discussed briefly as well., Comment: 32 pages, extension of quant-ph/9601006, posted on APS site at http://publish.aps.org/eprint/gateway/eplist/aps1997jun24_006

Certain transformations of isolated physical systems underlying various conservation laws in physics are noted. As regards each of these transformations, there is a theoretical action that is equivalent to a matched physical action on the system. Evidence supporting this thesis is found in experimental psychological research where results of various experiments allow that the imagined rotation of an object is analogous to a physical rotation. The conservation laws based on the transformations noted are theoretical or mental in nature to the same extent that they are physical. When one of the conservation principles noted is tested by carrying out the relevant transformation on the system, this test is essentially one of the influence of mental activity on physical reality., Comment: 2 pages, Perceptual and Motor Skills, 1985, vol. 60, p. 754

The personal spatial structure of an observer is introduced as a central element in the positioning of objects in space. The link between a reference frame used by an observer and his personal spatial structure is discussed. Research on inversion or reversal of incoming light in psychology indicates that the personal spatial structure of an individual, as well as a reference frame that he uses, depends on the internal coordination of sensory stimuli and that the position of objects in space depends in part on psychological factors that affect one's personal spatial structure. Other research in psychology demonstrating the flexibility for an observer in determining the direction of up-down relative to a particular figure, and indeed relative to the entire surround, is also noted and supports the thesis that the observer plays a role in the positioning of objects in space., Comment: 13 pages, minor corrections

Though Einstein and other physicists recognized the importance of an observer being at rest in an inertial reference frame for the special theory of relativity, the supporting psychological structures were not discussed much by physicists. On the other hand, Rock, a psychologist, wrote of the factors involved in the perception of motion, including one's own motion. Rock thus came to discuss issues of significance to relativity theory, apparently without any significant understanding of how his theory might be related to relativity theory. In this paper, connections between Rock's theory on the perception of one's own motion, as well as empirical work supporting it, and relativity theory are explored., Comment: 18 pages, no changes

Gravitational force manifested in its affect on rotational velocity is what indicates the presence of dark matter in individual galaxies. Newtonian mechanics is generally used to derive the relationship between rotational velocity and gravitational force. In Newtonian mechanics, mass is associated with gravitation. At the same time, in such galaxies there appears to be insufficient gravitational mass to account for the size of the gravitational force deduced from rotational velocity. The general theory of relativity encompasses Newtonian mechanics and also indicates that reference frames provide the means to develop spacetime curvature that expresses the gravitational field. It is reasonable to conclude that because of the more fundamental character of the general theory of relativity, the reference frames that are a key element of the general theory form the basis for understanding gravitation, and not mass., Comment: 5 pages; abstract and conclusion edited