arXiv subjects

Eric Steinbring

Publications and source records attributed to Eric Steinbring.

At least 19 recordsLinked to original sources

arXiv2026

Holographic Quantum Foam: Theoretical Underpinnings and Observational Evidence

Spacetime is foamy due to quantum fluctuations. Various gedanken experiments show that distances fluctuate by amounts consistent with the holographic principle, hence the name "holographic quantum foam" (HQF). One important prediction of HQF is that necessarily there exists a dark sector in the universe. The resulting cosmology is found (at least qualitatively) to be consistent with observations. Interestingly the quanta of the dark sector are found not to obey the familiar (fermionic or bosonic) statistics, but the exotic statistics known as infinite statistics (or quantum Boltzmann statistics). The most important challenge now is to check if HQF is consistent with experiments/observations. One way is to look for observational evidence of blurred distant point-sources due to physics at the Planck scale. For over two decades it has been debated whether those tiny inherent uncertainties in time and path-length can accumulate in transiting electromagnetic wavefronts from quasars and Gamma-Ray Bursts (GRBs). But a recent event is special: GRB221009A was extremely bright and energetic. That allowed follow-up across the whole spectrum from the optical/near-infrared through to X-rays, and including the highest-ever-recorded energy gamma-rays; all consistent with blurring by HQF. Those data, and a calculation of the HQF-widened point-spread function (PSF) for real telescopes viewing a GRB are presented.

gr-qc↗

arXiv2025

Observability of Acausal and Uncorrelated Optical-Quasar Pairs for Quantum-Mechanical Experiments

Viewing high-redshift sources at near-opposite directions on the sky can assure, by light-travel-time arguments, acausality between their emitted photons. One utility would be true random-number generation, by sensing these via two independent telescopes that each flip a switch based on those latest-arrived colours; for example, to autonomously control a quantum-mechanical (QM) experiment. Although demonstrated with distant quasars, those were not fully acausal pairs, which are restricted in simultaneous view from the ground at any single observatory. In optical light such faint sources also require large telescope aperture to avoid sampling assumptions when imaged at fast camera framerates: either unsensed intrinsic correlations between them or equivalently-correlated noise may ruin the expectation of pure randomness. One such case which could spoil a QM test is considered. Based on that, allowed geometries and instrumental limits are modelled for any two ground-based sites, and their data simulated. To compare, an analysis of photometry from the Gemini twin 8-m telescopes is presented, using archival data of well-separated bright stars, obtained with the instruments 'Alopeke (on Gemini-North in Hawai'i) and Zorro (on Gemini-South in Chile) simultaneously in two bands (centred at 562 nm and 832 nm) with 17 Hz framerate. No flux correlation is found, calibrating an analytic model, predicting where a search at signal-to-noise over 50 at 50 Hz with the same instrumentation can be made. Finally, the software PDQ (Predict Different Quasars) is presented which searches a large catalogue of known quasars, reporting those with brightness and visibility suitable to verify acausal, uncorrelated photons at those limits.

astro-ph.IM↗

arXiv2025

Observations of Holographic Quantum-Foam Blurring

The "foamy" nature of spacetime at the Planck scale was an idea first introduced by John Wheeler in the 1950s. And for the last twenty years or so it has been debated whether those inherent uncertainties in time and path-length might also accumulate in transiting electromagnetic wavefronts, resulting in measurable blurring for images of distant galaxies and quasars. A confusing aspect is that "pointlike" objects will always be blurred out somewhat by the optics of a telescope, especially in the optical. But it turns out that Gamma-Ray Bursts (GRBs) are more useful to test this, and have been observed by a host of ground-based and space-based telescopes, including by the Fermi observatory for well over a decade. And a recent one was unprecedented: GRB221009A was extremely bright, allowing follow-up from the infrared through the ultraviolet to X-rays and gamma-rays, including a first association with photons at high TeV energies. I will discuss how that observation is in direct tension with the calculus of how spacetime "foaminess" can add up in an image of a pointsource at cosmological distances, which at high-enough energy could spread these out over the whole sky without resulting in photon loss. A simple multiwavelength average of foam-induced blurring consistent with holographic quantum gravity is described, analogous to atmospheric seeing from the ground. This fits with measured instrumental point-spread functions and with the highest-energy localization of GRB221009A, resolving the observational issues and pointing to a key physical implication: spacetime does not look smooth.

astro-ph.HE↗

arXiv2023

Holographic Quantum-Foam Blurring, and Localization of Gamma-Ray Burst GRB221009A

Gamma-ray burst GRB221009A was of unprecedented brightness in gamma-rays and X-rays, and through to the far ultraviolet, allowing for identification within a host galaxy at redshift z=0.151 by multiple space and ground-based optical/near-infrared telescopes and enabling a first association - via cosmic-ray air-shower events - with a photon of 251 TeV. That is in direct tension with a potentially observable phenomenon of quantum gravity (QG), where spacetime "foaminess" accumulates in wavefronts propagating cosmological distances, and at high-enough energy could render distant yet bright pointlike objects invisible, by effectively spreading their photons out over the whole sky. But this effect would not result in photon loss, so it remains distinct from any absorption by extragalactic background light. A simple multiwavelength average of foam-induced blurring is described, analogous to atmospheric seeing from the ground. When scaled within the fields of view for the Fermi and Swift instruments, it fits all z<5 GRB angular-resolution data of 10 MeV or any lesser peak energy and can still be consistent with the highest-energy localization of GRB221009A: a limiting bound of about 1 degree is in agreement with a holographic QG-favored formulation.

astro-ph.HE↗

arXiv2022

Global Extinction: Combined Gemini North and South GMOS Photometry Relative to the Gaia Catalog, and Long-Term Atmospheric Change

Effects of long-term atmospheric change were looked for in photometry employing the Gemini North and South twin Multi-Object Spectrograph (GMOS-N and GMOS-S) archival data. The whole GMOS imaging database, beginning from 2003, was compared against the all-sky Gaia object catalog, yielding ~10^6 Sloan r'-filter samples, ending in 2021. These were combined with reported sky and meteorological conditions, versus a simple model of the atmosphere plus cloud together with simulated throughputs. One exceptionally extincted episode in 2009 is seen, as is a trend (similar at both sites) of about 2 mmag worsening attenuation per decade. This is consistent with solar-radiance transmissivity records going back over six decades, aerosol density measurements, and more than 0.2 deg C per decade rise in global air temperature, which has implications for calibration of historic datasets or future surveys.

astro-ph.IM↗

arXiv2021

Entering into the Wide Field Adaptive Optics Era on Maunakea

As part of the National Science Foundation funded "Gemini in the Era of MultiMessenger Astronomy" (GEMMA) program, Gemini Observatory is developing GNAO, a widefield adaptive optics (AO) facility for Gemini-North on Maunakea, the only 8m-class open-access telescope available to the US astronomers in the northern hemisphere. GNAO will provide the user community with a queue-operated Multi-Conjugate AO (MCAO) system, enabling a wide range of innovative solar system, Galactic, and extragalactic science with a particular focus on synergies with JWST in the area of time-domain astronomy. The GNAO effort builds on institutional investment and experience with the more limited block-scheduled Gemini Multi-Conjugate System (GeMS), commissioned at Gemini South in 2013. The project involves close partnerships with the community through the recently established Gemini AO Working Group and the GNAO Science Team, as well as external instrument teams. The modular design of GNAO will enable a planned upgrade to a Ground Layer AO (GLAO) mode when combined with an Adaptive Secondary Mirror (ASM). By enhancing the natural seeing by an expected factor of two, GLAO will vastly improve Gemini North's observing efficiency for seeing-limited instruments and strengthen its survey capabilities for multi-messenger astronomy.

astro-ph.IM↗

arXiv2020

Peak Quasar Correlation Across the Sky, and in an Earth-Wide Bell Test

Viewing two astronomical sources at large enough distance and angular separation can assure, by light-travel-time arguments, the acausality of their emitted photons. Using such photons to set apparatus parameters in a laboratory-based quantum-mechanical experiment could ensure those switch settings are independent and fair, allowing a loophole-free test of Bell's inequality. Quasars are a natural choice for this task, yet at ultimate extent it involves their simultaneous photometry towards opposite directions on the sky, which is untried. Cosmic isotropy can be invoked to set limits there, leaving fairness intact for causal pairs, but with a testable consequence of asymmetric bias: mean brightness correlations found less flat in sky angle than random, more acutely so inside a horizon of 90 degrees. Analysis of one dataset from the Gemini twin telescopes is presented, using over 14 years of archival broadband-optical images, serendipitously sampling thousands of quasars up to 180 degrees apart. These data reject a null result of no correlation with 97.7% confidence, instead consistent with a 3-sigma residual signal of 0.21 mag peaked at 65+/-3 degrees separation. Possible confirmatory observations are pointed to along with the improved experimental protocol of an Earth-wide test.

astro-ph.CO↗

arXiv2018

Potential for Quantum-Mechanical Tests Using Quasars, as Illuminated by Gemini Archival Data

There has been recent interest in quantum-mechanical tests aided by distant quasars. For two quasars of sufficient redshift at opposite directions on the sky, light-travel-time arguments can assure the acausality of their photons. And if those photons are used to set parameters in an Earth-based apparatus, coincidence cannot be due to their communication, closing the so-called "freedom of choice" loophole in the experiment. But this assumes no other interference right up to detection, including correlated instrumental errors, which must be carefully constrained. The Gemini North and South Multi-Object Spectrograph (GMOS) twins can simultaneously view pairs of quasars up to 180 degrees apart on the sky, and already provide a significant baseline record to investigate this. All GMOS broadband imaging frames were searched to find those that happen to contain a known quasar together with a suitable comparison star. Although individual photometry can be noisy among these 0.1 < z < 6 sources, in the aggregate, average site conditions and their relative photometric zeropoints are well characterized. The resulting dataset constitutes about 2 million correlated quasar-observation pairs over 14 years. A preliminary analysis of that is presented, with the intriguing result that paired-flux differences across the whole sky weakly deviate from flatness, to the limit consistent with Bell's Theorem. Can Gemini be used to prove the "spooky action at a distance" expected of quantum mechanics? Some prospects for future work and a more definitive test are considered.

astro-ph.IM↗

arXiv2018

Astronomy from Coast to Coast to Coast

Canada is a triangle-shaped country, roughly speaking. We all know that the Atlantic Ocean is at its eastern corner in the Maritimes, and off the west coast of British Columbia is the Pacific Ocean. The Arctic Ocean, however, makes up the bulk of Canada's coastline, along its pointy "top." That peaks closest to the North Pole in Nunavut, on the shores of Ellesmere Island. Running down this island, as on our western flank in the Rockies, is a range of permanently snowcapped mountains, with one topping 2600 m. It is a propitious geography, which along with that of northern Greenland, provides plenty of ice-locked, and windward, elevated coastal terrain; potentially perfect for astronomy. Actually, these mountains are about the same distance from either Halifax or Victoria (or Halifax to Victoria) as Victoria is from the amazing 4200-m summit of Maunakea, on the Big Island of Hawai'i - although they are not as easily reached.

astro-ph.IM↗

arXiv2016

Thermal Infrared Sky Background for a High-Arctic Mountain Observatory

Nighttime zenith sky spectral brightness in the 3.3 to 20 micron wavelength region is reported for an observatory site nearby Eureka, on Ellesmere Island in the Canadian High Arctic. Measurements derive from an automated Fourier-transform spectrograph which operated continuously there over three consecutive winters. During that time the median through the most transparent portion of the Q window was 460 Jy/square-arcsec, falling below 32 Jy/square-arcsec in N band, and to sub-Jansky levels by M and shortwards; reaching only 36 mJy/square-arcsec within L. Nearly six decades of twice-daily balloonsonde launches from Eureka, together with contemporaneous meteorological data plus a simple model allows characterization of background stability and extrapolation into K band. This suggests the study location has dark skies across the whole thermal infrared spectrum, typically sub-200 micro-Jy/square-arcsec at 2.4 microns. That background is comparable to South Pole, and more than an order of magnitude less than estimates for the best temperate astronomical sites, all at much higher elevation. Considerations relevant to future facilities, including for polar transient surveys, are discussed.

astro-ph.IM↗

arXiv2016

Unveiling the Dynamic Infrared Sky with Gattini-IR

While optical and radio transient surveys have enjoyed a renaissance over the past decade, the dynamic infrared sky remains virtually unexplored. The infrared is a powerful tool for probing transient events in dusty regions that have high optical extinction, and for detecting the coolest of stars that are bright only at these wavelengths. The fundamental roadblocks in studying the infrared time-domain have been the overwhelmingly bright sky background (250 times brighter than optical) and the narrow field-of-view of infrared cameras (largest is 0.6 sq deg). To begin to address these challenges and open a new observational window in the infrared, we present Palomar Gattini-IR: a 25 sq degree, 300mm aperture, infrared telescope at Palomar Observatory that surveys the entire accessible sky (20,000 sq deg) to a depth of 16.4 AB mag (J band, 1.25um) every night. Palomar Gattini-IR is wider in area than every existing infrared camera by more than a factor of 40 and is able to survey large areas of sky multiple times. We anticipate the potential for otherwise infeasible discoveries, including, for example, the elusive electromagnetic counterparts to gravitational wave detections. With dedicated hardware in hand, and a F/1.44 telescope available commercially and cost-effectively, Palomar Gattini-IR will be on-sky in early 2017 and will survey the entire accessible sky every night for two years. Palomar Gattini-IR will pave the way for a dual hemisphere, infrared-optimized, ultra-wide field high cadence machine called Turbo Gattini-IR. To take advantage of the low sky background at 2.5 um, two identical systems will be located at the polar sites of the South Pole, Antarctica and near Eureka on Ellesmere Island, Canada. Turbo Gattini-IR will survey 15,000 sq. degrees to a depth of 20AB, the same depth of the VISTA VHS survey, every 2 hours with a survey efficiency of 97%.

astro-ph.IM↗

arXiv2015

Limits to Seeing High-Redshift Galaxies Due to Planck-Scale-Induced Blurring

In the last decade or so there has been debate over the possibility that the fuzzy quantum nature of spacetime might decohere wavefronts emanating from very distant sources. Consequences of that could be "blurred" or "faded" images of compact structures in galaxies, primarily at z>1 for their emitted X-rays and gamma-rays, but perhaps even in ultraviolet through optical light at higher redshift. So far there are only inconclusive hints of this from z~4 active-galactic nucleii and gamma-ray bursts viewed with Fermi and Hubble Space Telescope. If correct though, that would impose a significant, fundamental resolution limit for galaxies out to z~8 in the era of the James Webb Space Telescope and the next generation of ground-based telescopes using adaptive optics.

astro-ph.GA↗

arXiv2015

Detectability of Planck-Scale-Induced Blurring with Gamma-Ray Bursts

Microscopic fluctuations inherent to the fuzziness of spacetime at the Planck scale might accumulate in wavefronts propagating a cosmological distance and lead to noticeable blurring in an image of a pointlike source. Distant quasars viewed in the optical and ultraviolet with Hubble Space Telescope (HST} may show this weakly, and if real suggests a stronger effect should be seen for Gamma-Ray Bursts (GRBs) in X-rays and gamma-rays. Those telescopes, however, operate far from their diffraction limits. A description of how Planck-scale-induced blurring could be sensed at high energy, even with cosmic rays, while still agreeing with the HST results is discussed. It predicts dilated apparent source size and inflated uncertainties in positional centroids, effectively a threshold angular accuracy restricting knowledge of source location on the sky. These outcomes are found to be consistent with an analysis of the 10 highest-redshift GRB detections reported for the Fermi satellite. Confusion with photon cascade and scattering phenomena is also possible; prospects for a definitive multiwavelength measurement are considered.

astro-ph.HE↗

arXiv2014

Ukaliq: Seeing Long-Term with Small, Precise Arctic Telescopes

Time-domain astrophysics benefits from extreme-latitude sites, which can combine intrinsically extended nighttime with good sky conditions. One such location is the Polar Environment Atmospheric Research Laboratory (PEARL), at 80 degrees North latitude, on the northwestern edge of Ellesmere Island, Canada. Experience gained deploying seeing monitors there has been incorporated into an automated system called "Ukaliq" after the common arctic hare, which is also very well suited to its local environment. Even with modest aperture, high photometric reliability may be achieved using simple adaptive optics together with observing strategies that best fit the unique set of advantages available at PEARL: excellent image quality maintained during many clear, calm, dark periods of 100 hours or more. A potential multi-year search for gravitational microlensing of quasars with Ukaliq helps illustrate this niche in the era of large wide-field survey facilities.

astro-ph.IM↗

arXiv2014

A Star-Forming Shock Front in Radio Galaxy 4C+41.17 Resolved with Laser-Assisted Adaptive Optics Spectroscopy

Near-infrared integral-field spectroscopy of redshifted [O III], H-beta and optical continuum emission from z=3.8 radio galaxy 4C+41.17 is presented, obtained with the laser-guide-star adaptive optics facility on the Gemini North telescope. Employing a specialized dithering technique, a spatial resolution of 0.10 arcsec or 0.7 kpc is achieved in each spectral element, with velocity resolution of ~70 km/s. Spectra similar to local starbursts are found for bright knots coincident in archival Hubble Space Telescope (HST) restframe-ultraviolet images, which also allows a key line diagnostic to be mapped together with new kinematic information. There emerges a clearer picture of the nebular emission associated with the jet in 8.3 GHz and 15 GHz Very Large Array maps, closely tied to a Ly-alpha-bright shell-shaped structure seen with HST. This supports a previous interpretation of that arc tracing a bow shock, inducing 10^10-11 M_solar star-formation regions that comprise the clumpy broadband optical/ultraviolet morphology near the core.

astro-ph.GA↗

arXiv2013

Preliminary DIMM and MASS Nighttime Seeing Measurements at PEARL, in the Canadian High Arctic

Results of deploying a Differential Image Motion Monitor (DIMM) and a DIMM combined with a Multi-Aperture Scintillation Sensor (MASS/DIMM) are reported for campaigns in 2011 and 2012 on the roof of the Polar Environment Atmospheric Research Laboratory (PEARL). This facility is on a 610-m-high ridge at latitude 80 degrees N, near the Eureka weatherstation on Ellesmere Island, Canada. The median seeing at 8-m elevation is 0.85 arcsec or better based on DIMM data alone, but is dependent on wind direction, and likely includes a component due to the PEARL building itself. Results with MASS/DIMM yield a median seeing less than 0.76 arcsec. A semi-empirical model of seeing versus ground wind speed is introduced which allows agreement between these datasets, and with previous boundary-layer profiling by lunar scintillometry from the same location. This further suggests that best 20 percentile seeing reaches 0.53 arcsec, of which typically 0.30 arcsec is due to the free atmosphere. Some discussion for guiding future seeing instrumentation and characterization at this site is provided.

astro-ph.IM↗

arXiv2012

Exoplanets from the Arctic: The First Wide-Field Survey at 80 Degrees North

Located within 10 degrees of the North Pole, northern Ellesmere Island offers continuous darkness in the winter months. This capability can greatly enhance the detection efficiency of planetary transit surveys and other time domain astronomy programs. We deployed two wide-field cameras at 80 degrees North, near Eureka, Nunavut, for a 152-hour observing campaign in February 2012. The 16-megapixel-camera systems were based on commercial f/1.2 lenses with 70mm and 42mm apertures, and they continuously imaged 504 and 1,295 square degrees respectively. In total, the cameras took over 44,000 images and produced better-than-1% precision light curves for approximately 10,000 stars. We describe a new high-speed astrometric and photometric data reduction pipeline designed for the systems, test several methods for the precision flat-fielding of images from very-wide-angle cameras, and evaluate the cameras' image qualities. We achieved a scintillation-limited photometric precision of 1-2% in each 10s exposure. Binning the short exposures into 10-min chunks provided a photometric stability of 2-3 millimagnitudes, sufficient for the detection of transiting exoplanets around the bright stars targeted by our survey. We estimate that the cameras, when operated over the full arctic winter, will be capable of discovering several transiting exoplanets around bright (V<9) stars.

astro-ph.EP↗

arXiv2012

New Exoplanet Surveys in the Canadian High Arctic at 80 Degrees North

Observations from near the Eureka station on Ellesmere Island, in the Canadian High Arctic at 80 degrees North, benefit from 24-hour darkness combined with dark skies and long cloud-free periods during the winter. Our first astronomical surveys conducted at the site are aimed at transiting exoplanets; compared to mid-latitude sites, the continuous darkness during the Arctic winter greatly improves the survey's detection efficiency for longer-period transiting planets. We detail the design, construction, and testing of the first two instruments: a robotic telescope, and a set of very wide-field imaging cameras. The 0.5m Dunlap Institute Arctic Telescope has a 0.8-square-degree field of view and is designed to search for potentially habitable exoplanets around low-mass stars. The very wide field cameras have several-hundred-square-degree fields of view pointed at Polaris, are designed to search for transiting planets around bright stars, and were tested at the site in February 2012. Finally, we present a conceptual design for the Compound Arctic Telescope Survey (CATS), a multiplexed transient and transit search system which can produce a 10,000-square-degree snapshot image every few minutes throughout the Arctic winter.

astro-ph.EP↗