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Stanley L. Robertson

Publications and source records attributed to Stanley L. Robertson.

18 recordsLinked to original sources
arXiv2020

MECO In An Exponential Metric

Magnetic Eternally Collapsing Objects (MECO) have been proposed as the central engines of galactic black hole candidates (GBHC) and supermassive active galactic nuclei (AGN). Previous work has shown that their luminosities and spectral and timing characteristics are in good agreement with observations. These features and the formation of jets are generated primarily by the interactions of accretion disks with an intrinsically magnetic central MECO. The interaction of accretion disks with the anchored magnetic fields of the central objects permits a unified description of properties for GBHC, AGN, neutron stars in low mass x-ray binaries and dwarf novae systems. The previously published MECO models have been based on a quasistatic Schwarzschild metric of General Relativity; however, the only essential feature of this metric is its ability to produce extreme gravitational redshifts. For reasons discussed in this article, an alternative development based on a quasistatic exponential metric is considered here.

physics.gen-ph↗
arXiv2015

Yilmaz Theory of SNe 1a Redshift

A redshift-luminosity distance relation in excellent agreement with observations is calculated here for SNe 1a using the Yilmaz gravitational theory. In contrast to the current conventional explanation based on general relativity, the Yilmaz theory does not require a cosmological constant term that implies the existence of "dark energy". The Yilmaz theory requires only one parameter; a mean mass-energy density of the cosmos. The required value is essentially the same as the critical density for a Friedmann-Robertson-Walker cosmological metric. The Yilmaz theory therefore still requires the existence of non-baryonic dark matter.

physics.gen-ph↗
arXiv2008

Does Sgr A* Have an Intrinsic Magnetic Moment Instead of an Event Horizon?

In previous work we have developed a general relativistic, magnetospheric eternally collapsing object (MECO) model for black hole candidates and shown that the model is consistent with broad band spectral and luminosity characteristics and accounts for the radio/x-ray luminosity correlations of both galactic black hole candidates (GBHC) and active galactic nuclei (AGN). We show here that the MECO model can: a) satisfy the luminosity constraints that have been claimed as proof of an event horizon for Sgr A*, b) reconcile the low bolometric luminosity with the expected Bondi accretion rate for Sgr A* by means of a magnetic propeller driven outflow, c) account for the Sgr A* NIR and x-ray luminosities, the general characteristics of its broad band spectrum, and the sequence of flares in different spectral ranges as well as the pattern of its observed orthogonal polarizations. We also include specific predictions for images that may be obtained in sub-millimeter to NIR wavelengths in the near future. Additional future tests for the presence of an intrinsic magnetic moment for Sgr A* will require global solutions for electron density and magnetic field distributions in a Bondi accretion flow into a compact, rotating magnetic dipole. These will provide for definitive tests in the form of detailed calculations of spectral and spatial luminosity distributions and polarization maps for direct comparison with high resolution images of Sgr A*.

astro-ph↗
arXiv2007

Direct Microlensing-Reverberation Observations of the Intrinsic magnetic Structure of AGN in Different Spectral States: A Tale of Two Quasars

We show how direct microlensing-reverberation analysis performed on two well-known Quasars (Q2237 - The Einstein Cross and Q0957 - The Twin) can be used to observe the inner structure of two quasars which are in significantly different spectral states. These observations allow us to measure the detailed internal structure of quasar Q2237 in a radio quiet high-soft state, and compare it to quasar Q0957 in a radio loud low-hard state. We find that the observed differences in the spectral states of these two quasars can be understood as being due to the location of the inner radii of their accretion disks relative to the co-rotation radii of rotating intrinsically magnetic supermassive compact objects in the centers of these quasars.

astro-ph↗
arXiv2007

A Gedanken Experiment For Gravitomagnetism

A gedanken experiment implies the existence of gravitomagnetism and raises a question about what we know about the weak-field limit of the gravitomagnetic field of General Relativity.

gr-qc↗
arXiv2006

Observations Supporting the Existence of an Intrinsic Magnetic Moment Inside the Central Compact Object Within the Quasar Q0957+561

Recent auto-correlation and fluctuation analysis of time series data in the brightness curves and micro-lensing size scales seen in Q0957+561 A,B has produced important information about the existence and characteristic physical dimensions of a new non-standard internal structure contained within this quasar. We find that the new internal quasar structure, which we shall call the Schild-Vakulik Structure, can be consistently explained in terms of a new class of gravitationally collapsing solutions to the Einstein field equations which describe highly redshifted, Eddington limited, Magnetospheric Eternally Collapsing Objects (MECO) that contain intrinsic magnetic moments. Since observation of the Schild-Vakulik structure within Q0957+561 implies that this quasar contains an observable intrinsic magnetic moment, this represents strong evidence that this quasar does not have an event horizon

astro-ph↗
arXiv2006

The Magnetospheric Eternally Collapsing Object (MECO) Model of Galactic Black Hole Candidates and Active Galactic Nuclei

The spectral, timing, and jet formation properties of neutron stars in low mass x-ray binary systems are influenced by the presence of central magnetic moments. Similar features shown by the galactic black hole candidates (GBHC) strongly suggest that their compact cores might be intrinsically magnetic as well. We show that the existence of intrinsically magnetic GBHC is consistent with a new class of solutions of the Einstein field equations of General Relativity. These solutions are based on a strict adherence to the Strong Principle of Equivalence (SPOE) requirement that the world lines of physical matter must remain timelike in all regions of spacetime. The new solutions emerge when the structure and radiation transfer properties of the energy momentum tensor on the right hand side of the Einstein field equations are appropriately chosen to dynamically enforce this SPOE requirement of timelike world line completeness. In this context, we find that the Einstein field equations allow the existence of highly red shifted, Magnetospheric, Eternally Collapsing Objects (MECO). MECO necessarily possess intrinsic magnetic moments and they do not have trapped surfaces that lead to event horizons and curvature singularities. Their most striking features are equipartition magnetic fields, pair plasma atmospheres and extreme gravitational redshifts. Since MECO lifetimes are orders of magnitude greater than a Hubble time, they provide an elegant and unified framework for understanding a broad range of observations of GBHC and active galactic nuclei. We examine their spectral, timing and jet formation properties and discuss characteristics that might lead to their confirmation.

astro-ph↗
arXiv2005

Newtonian Gravity Predictions For Gravity Probe B

Newtonian gravity and special relativity combine to produce a gravitomagnetic precession of an orbiting gyroscope that is one fourth as large as predicted by General Relativity. The geodetic effect is the same in both cases.

gr-qc↗
arXiv2004

On the Origin of the Radio/X-Ray Luminosity Correlation in Black Hole Candidates

In previous work we found that the spectral state switch and other spectral properties of both neutron star (NS) and galactic black hole candidates (GBHC), in low mass x-ray binary systems could be explained by a magnetic propeller effect that requires an intrinsically magnetic central compact object. In later work we showed that intrinsically magnetic GBHC could be easily accommodated by general relativity in terms of magnetospheric eternally collapsing objects (MECO), with lifetimes greater than a Hubble time, and examined some of their spectral properties. In this work we show how a standard thin accretion disk and corona can interact with the central magnetic field in atoll class NS, and GBHC and active galactic nuclei (AGN) modeled as MECO, to produce jets that emit radio through infrared luminosity $L_R$ that is correlated with mass and x-ray luminosity as $L_R \propto M^{0.75 - 0.92}L_x^{2/3}$ up to a mass scale invariant cutoff at the low/high spectral state switch. Comparing the MECO-GBHC/AGN model to observations, we find that the correlation exponent, the mass scale invariant cutoff, and the radio luminosity ratios of AGN, GBHC and atoll class NS are correctly predicted, which strongly implies that GBHC and AGN have observable intrinsic magnetic moments and hence do not have event horizons.

astro-ph↗
arXiv2003

On Intrinsic Magnetic Moments In Black Hole Candidates

In previous work we found that many of the spectral properties of low mass x-ray binaries, including galactic black hole candidates could be explained by a magnetic propeller model that requires an intrinsically magnetized central object. Here we describe how the Einstein field equations of General Relativity and equipartition magnetic fields permit the existence of highly red shifted, extremely long lived, collapsing, radiating objects. We examine the properties of these collapsed objects and discuss characteristics that might lead to their confirmation as the source of black hole candidate phenomena.

astro-ph↗
arXiv2003

Do Black Hole Candidates Have Magnetic Moments Instead of Event Horizons?

In previous work we found that many of the spectral properties of low mass x-ray binaries (LMXB), including galactic black hole candiates (GBHC) were consistent with the existence of intrinsically magnetized central objects. We review and extend these findings and show that the existence of intrisically magnetic BHC is consistent with a new class of solutions of the Einstein field equations of General Relativity. These solutions are based on a strict adherence to the Strong Principle of Equivalence (SPOE) requirement that the world lines of physical matter must remain timelike in all regions of spacetime. The new solutions emerge when the structure and radiation transfer properties of the energy momentum tensor on the right hand side of the Einstein field equations are appropriately chosen to dynamically enforce the SPOE requirement of timelike world line completeness. In this context, we find that the Einstein field equations allow the existence of highly red shifted, Magnetospheric, Eternally Collapsing Objects (MECO). MECO can possess intrinsic magnetic moments since they do not have trapped surfaces that lead to event horizons and curvature singularities. Since MECO lifetimes are orders of magnitude greater than a Hubble time, they provide an elegant and unified framework for understanding a broad range of observations of GBHC and active galactic nuclei. We examine their properties and discuss characteristics that might lead to their confirmation.

astro-ph↗
arXiv2003

Einstein General Relativity In Bi-metric Spacetime Contains Exponential Metrics Which Dynamically Preserve Bi-metric "Light Cone Causality"

It is well known that Einstein General Relativity can be expressed covariantly in bi-metric spacetime, without the uncertainties which arise from the effects of gravitational energy-momentum pseudo-tensors. However the effect that the Strong Principle of Equivalence (SPOE) has on the curved and flat bi-metric spacetime tetrad structure has not been fully explored. In the context of bi-metric General Relativity the (SPOE) requires that: a) in the absence of gravitation due to spacetime curvature a Global Inertial Cartesian Minkowski (GICM) spacetime frame exists in which Special Relativity is valid and, b) in the presence of gravitation due to spacetime curvature a bi-metric Local Free Fall frame (LFF) must always exist. These two conditions required by the (SPOE) are then shown to imply that a symmetric gravitational potential tensor must exist in the bi-metric spacetime which is connected exponentially to the tetrad inner product between the curved symmetric tetrads and the flat background symmetric tetrads. It is then shown that this (SPOE) generated gravitational potential tensor has the property of exponentially connecting the curved metric tensor with the flat background metric tensor in a manner which allows the condition of "Light Cone Causality" (LCC) to be dynamically satisfied in the bi-metric spacetime. Substitution of this (LCC) conserving exponential metric into the bi-metric Einstein field equations, subject to an appropriate choice of tensor gauge conditions, yields an equivalent set of (LCC) conserving bi-metric Einstein field equations for the gravitational potential tensor, the full implications of which will be explored in future papers.

gr-qc↗
arXiv2002

How Black Are Black Hole Candidates?

In previous work we found that many of the spectral properties of x-ray binaries, including both galactic black hole candiates (GBHC) and neutron stars, were consistent with the existence of intrinsically magnetized central objects. Here we review and extend the observational evidence for the existence of intrinsically magnetized GBHC and show that their existence is consistent with a new class of solutions of the Einstein field equations of General Relativity. These solutions are based on a strict adherence to the Principle of Equivalence, which prevents the time-like geodesics of physical matter from becoming null on trapped surfaces of infinite red shift. The new solutions emerge from the fact that the structure and radiation transfer properties of the energy-momentum tensor on the right hand side of the Einstein field equations must have a form that is consistent with this Principle of Equivalence requirement. In this context, we show that the Einstein field equations allow the existence of highly red shifted, magnetospheric, eternally collapsing objects (MECO) which do not have trapped surfaces which lead to event horizons. Since MECO lifetimes are many orders of magnitude greater than a Hubble time, they provide an elegant and unified framework for understanding the broad range of observations associated with GBHC and active galactic nuclei.

astro-ph↗
arXiv2001

Evidence For Intrinsic Magnetic Moments in Black Hole Candidates

We present evidence that the power law part of the quiescent x-ray emissions of neutron stars in low mass x-ray binaries is magnetospheric in origin. It can be very accurately calculated from known rates of spin and magnetic moments determined from the the $\sim 10^{3 - 4}$ times brighter luminosity at the transition to the hard spectral state. This strongly suggests that the spectral state transition for neutron stars is a magnetospheric propeller effect. We test the hypothesis that the similar spectral state switches and quiescent power law emissions of the black hole candidates might also be magnetospheric effects. In the process we derive proposed magnetic moments and rates of spin for them and accurately predict their quiescent luminosities. This constitutes an observational test for the physical realization of event horizons and suggests that they may not be formed during the gravitational collapse of ordinary matter.

astro-ph↗
arXiv1999

Do Black Holes Exist?

Proof that black holes exist will likely require confirmation of the existence of event horizons. The common assumption that the mere existence of large compact masses proves the case for black holes is an unwarranted extrapolation of General Relativity into a strong-field regime where it has not been adequately tested. Neither the large compact masses of galactic nuclei nor the massive compact objects of stellar mass in the x-ray binaries prove the existence of black holes. In contrast to the case for galactic nuclei, we have the necessary tools for obtaining either proof or disproof of event horizons in the x-ray binaries. Observations of kHz QPOs may decide the event horizon issue very quickly. If not, we can still obtain proof by comparing predictions of gravity theories that differ primarily by the presence or absence of an event horizon. Detailed analysis of models of x-ray binaries would then decide the issue.

astro-ph↗
arXiv1999

Bigger Bursts From Merging Neutron Stars

GRB 990123 may have radiated more than one solar mass equivalent in just its gamma emissions. Though this may be within the upper limit of the binding energy available from neutron stars in the Schwarzschild metric, it is difficult to imagine a process with the required efficiency of conversion to gamma rays. Neutron stars of ~10 solar mass are permitted in the Yilmaz metric. A merger of two neutron stars of maximum mass could release approximately 10 solar mass equivalent binding energy.

astro-ph↗
arXiv1998

The Intrinsic Magnetic Fields of the Galactic Black Hole Candidates

Recent work has linked the quiescent luminosities and hard/soft spectral state switches of neutron stars (NSs) to their spinning magnetic fields. It is shown here that the quiescent luminosities and spectral switches of galactic black hole candidates (BHCs) could be produced in the same way for spin rates below 100 Hz and magnetic fields above 10^10 G. It is also shown that the ultrasoft peaks and large flickering amplitudes of the BHCs would be expected from the surfaces of massive NSs. None of the few spectral characteristics that distinguish BHCs from low mass NSs have been explained in terms of event horizons. Serious consideration of the possibility that they might simply be massive NSs opens an avenue for proof of event horizons by negation, but requires the use of a space-time metric that has no event horizon. The Yilmaz exponential metric used here is shown to have an innermost marginally stable orbit with radius, binding energy and Keplerian frequency that are within a few percent of the same quantities for the Schwarzschild metric. A maximum NS mass of ~10 solar mass is found for the Yilmaz metric. The two metrics essentially differ only by the presence/absence of a surface for the BHCs, thus enabling proof or disproof of the existence of an event horizon.

astro-ph↗