Negative / Null Result ReportOpen accessComputer Science
N. J. Ayres · 2018 · arXiv
We report on a search for ultra-low-mass axion-like dark matter by analysing the ratio of the spin-precession frequencies of stored ultracold neutrons and $^{199}$Hg atoms for an axion-induced oscillating electric dipole moment of the neutron and an axion-wind spin-precession effect. No signal consistent with dark matter is observed for the axion mass range $10^{-24}~\textrm{eV} \le m_a \le 10^{-17}~\textrm{eV}$. Our null result sets the first laboratory constraints on the coupling of axion dark matter to gluons, which improve on astrophysical limits by up to 3 orders of magnitude, and also im
Negative / Null Result ReportOpen accessComputer Science
Robert McCarthy, Daniel C. H. Tan, Dominik Schmidt et al. · 2024 · arXiv
Scaling deep learning to massive and diverse internet data has driven remarkable breakthroughs in domains such as video generation and natural language processing. Robot learning, however, has thus far failed to replicate this success and remains constrained by a scarcity of available data. Learning from videos (LfV) methods aim to address this data bottleneck by augmenting traditional robot data with large-scale internet video. This video data provides foundational information regarding physical dynamics, behaviours, and tasks, and can be highly informative for general-purpose robots. This su
Negative / Null Result ReportOpen accessComputer Science
S. Cecchini, M. Cozzi, D. Di Ferdinando et al. · 2008 · arXiv
The SLIM experiment at the Chacaltaya high altitude laboratory was sensitive to nuclearites and Q-balls, which could be present in the cosmic radiation as possible Dark Matter components. It was sensitive also to strangelets, i.e. small lumps of Strange Quark Matter predicted at such altitudes by various phenomenological models. The analysis of 427 m^2 of Nuclear Track Detectors exposed for 4.22 years showed no candidate event. New upper limits on the flux of downgoing nuclearites and Q-balls at the 90% C.L. were established. The null result also restricts models for strangelets propagation th
Negative / Null Result ReportOpen accessTechnology
Sunthorn Sotthibandhu · 2003 · Songklanakarin Journal of Science and Technology (SJST)
The territorial behavior of the red-whiskered bulbul, Pycnonotus jocosus, was studied in the semiwild habitat of a bird farm compound in the District of Chana, Songkhla Province, the south of Thailand. The male and female birds were bred and reared in the farm till they reached maturity following which they were released to the wild. A mating pair was later formed and their territory established in the farm area. A decoy was used to simulate a natural intruder to the defended area. Ten test stations were sited in the four cardinal points of the compass and with reference to the farmhouse. The
Negative / Null Result ReportOpen accessPhysics
I. Lőrincz, M. Tajmar · 2015 · arXiv
A number of weight anomalies have been reported in the past with respect to gyroscopes. Much attention was gained from a paper in Physical Review Letters, when Japanese scientists announced that a gyroscope loses weight up to $0.005\%$ when spinning only in the clockwise rotation with the gyroscope's axis in the vertical direction. Immediately afterwards, a number of other teams tried to replicate the effect, obtaining a null result. It was suggested that the reported effect by the Japanese was probably due to a vibration artifact, however, no final conclusion on the real cause has been obtain
Negative / Null Result ReportOpen access
Oates, David, David Oates · 1976
The concentration of lead in fish muscle tissue from lakes where boating is heavy and where it is prohibited was measured. The lead levels ranged from less than 0.05 to 1.35 ppm but did not differ significantly between those in the…
View details →DOI: 10.2307/3627294 Negative / Null Result ReportOpen accessComputer Science
Masahiro Kawasaki, Masaki Yamada, Tsutomu T. Yanagida et al. · 2015 · arXiv
We provide an anthropic reason that the supersymmetry breaking scale is much higher than the electroweak scale as indicated by the null result of collider experiments and observed 125 GeV Higgs boson. We focus on a new inflation model as a typical low-scale inflation model that may be expected in the string landscape. In this model, the R-symmetry is broken at the minimum of the inflaton potential and its breaking scale is related to the reheating temperature. Once we admit that the anthropic principle requires thermal leptogenesis, we obtain a lower bound on gravitino mass, which is related t
Negative / Null Result ReportOpen accessPhysics
Samuel Lederer, Wen Huang, Edward Taylor et al. · 2014 · arXiv
A major challenge to the chiral $p$-wave hypothesis for the pairing symmetry of the unconventional superconductor Sr$_2$RuO$_4$ is the null result of sensitive scanning magnetometry experiments designed to detect the expected spontaneous charge currents. Motivated by junction tunneling conductance measurements which indicate the quenching of superconductivity at the surfaces of even high-purity samples, we examine the spontaneous currents in a chiral $p$-wave superconductor near a normal metal / superconductor interface using the lattice Bogoliubov-de Gennes equations and Ginzburg-Landau theor
Negative / Null Result ReportOpen accessComputer Science
Javier De Miguel, Evanthia Hatziminaoglou, Frédéric Poidevin et al. · 2025 · arXiv
We report a mm-wave search for axion dark matter from SGR 1745-2900, based on 4.8 h of ALMA observations. No candidate features are found between 133.99-135.78, 135.91-137.70, 145.99-147.78, and 147.99-149.78~GHz, corresponding to 0.55-0.62 meV. Interpreting this null result within a state-of-the-art stellar framework, we derive sensitivity to the axion-photon coupling at the level of $g_γ\gtrsim 2\times10^{-11}$ GeV$^{-1}$ under a standard Navarro-Frenk-White profile; down to $g_γ\gtrsim 2\times10^{-13}$ GeV$^{-1}$ upon accounting for a dense dark-matter spike around Sagittarius A*, probing t
Negative / Null Result ReportOpen accessComputer Science
Riccardo Catena, Alejandro Ibarra, Sebastian Wild · 2016 · arXiv
We examine the dark matter interpretation of the modulation signal reported by the DAMA experiment from the perspective of effective field theories displaying Galilean invariance. We consider the most general effective coupling leading to the elastic scattering of a dark matter particle with spin 0 or 1/2 off a nucleon, and we analyze the compatibility of the DAMA signal with the null results from other direct detection experiments, as well as with the non-observation of a high energy neutrino flux in the direction of the Sun from dark matter annihilation. To this end, we develop a novel semi-
Negative / Null Result ReportOpen accessPhysics
B. Scott Gaudi · 2002 · arXiv
I review results from, and future prospects for, microlensing searches for extrasolar planets. Analyses of well-sampled microlensing light curves by several collaborations have demonstrated that current searches are sensitive to Jupiter-mass planets with few AU separations from M-dwarfs in the Galactic bulge. To date, however, no unambiguous planetary detections have been made. Detailed analysis has shown that this null result implies that <33% of typical stars (i.e. M-dwarfs) in the Galactic bulge have Jupiter-mass companions with separations between 1.5 and 4 AU, and <45% have three-Jupiter-
Negative / Null Result ReportOpen accessComputer Science
Esteban Alcantara, Luis A. Anchordoqui, Jorge F. Soriano · 2019 · arXiv
In 15 years of data taking the Pierre Auger Observatory has observed no events beyond $10^{11.3}$ GeV. This null result translates into an upper bound on the flux of ultrahigh-energy cosmic rays implying $J (> 10^{11.3}$ GeV) $< 3.6 \times 10^{-5}$ km$^{-2}$ sr$^{-1}$ yr$^{-1}$, at the 90\%C.L. We interpret this bound as a constraint on extreme-energy photons originating in the decay super-heavy dark matter (SHDM) particles clustered in the Galactic halo. Armed with this constraint we derive the strongest lower limit on the lifetime of hadronically decaying SHDM particles with masses in the ra
Negative / Null Result ReportOpen accessPhysics
Peter R. Allen, David W. Koerner, Michael W. McElwain et al. · 2006 · arXiv
We present the results of a deep-imaging search for wide companions to low-mass stars and brown dwarfs using NSFCam on IRTF. We searched a sample of 132 M7-L8 dwarfs to magnitude limits of $J \sim 20.5$ and $K \sim 18.5$, corresponding to secondary-primary mass ratios of $\sim 0.5$. No companions were found with separations between $2{\arcsec}$ to $31{\arcsec}$ ($\sim$40 AU to $\sim$1000 AU). This null result implies a wide companion frequency below 2.3% at the 95% confidence level within the sensitivity limits of the survey. Preliminary modeling efforts indicate that we could have detected 85
Negative / Null Result ReportOpen accessPhysics
Robert J. Nemiroff, Gabriela F. Marani, Jay P. Norris et al. · 2001 · arXiv
A new search for the gravitational lens effects of a significant cosmological density of supermassive compact objects (SCOs) on gamma-ray bursts has yielded a null result. We inspected the timing data of 774 BATSE-triggered GRBs for evidence of millilensing: repeated peaks similar in light-curve shape and spectra. Our null detection leads us to conclude that, in all candidate universes simulated, $Ω_{SCO} < 0.1$ is favored for $10^5 < M_{SCO}/M_{\odot} < 10^9$, while in some universes and mass ranges the density limits are as much as 10 times lower. Therefore, a cosmologically significant popu
Negative / Null Result ReportOpen accessPhysics
Yuichiro Ando, Takahiro Hamasaki, Takayuki Kurokawa et al. · 2014 · arXiv
We detected the spin polarization due to charge flow in the spin non-degenerate surface state of a three dimensional topological insulator by means of an all-electrical method. The charge current in the bulk-insulating topological insulator Bi1.5Sb0.5Te1.7Se1.3 (BSTS) was injected/extracted through a ferromagnetic electrode made of Ni80Fe20, and an unusual current-direction-dependent magnetoresistance gives evidence for the appearance of spin polarization which leads to a spin-dependent resistance at the BSTS/Ni80Fe20 interface. In contrast, our control experiment on Bi2Se3 gave null result. T
Negative / Null Result ReportOpen accessPhysics
Allyn Dullighan, George Ricker, Nathaniel Butler et al. · 2004 · arXiv
We present an upper limit on the brightness of the afterglow of the long GRB 030115 measured from Infrared (IR) images taken with the Magellan Classic Cam instrument of Ks > 22 at 6.2 days after the burst. We also present measurments of the host galaxy of GRB 030115 from archival optical and IR HST images taken with the Advanced Camera for Surveys and the Near Infrared Camera and Multi Object Spectrometer 25+ days after the burst. GRB 030115 is classified as an Optically Dark Burst, as its afterglow was found in the J, H, and K IR bands after a null result was reported in the optical. This is
Negative / Null Result ReportOpen accessComputer Science
Harvey R Brown · 2001 · arXiv
One of the widespread confusions concerning the history of the 1887 Michelson-Morley experiment has to do with the initial explanation of this celebrated null result due independently to FitzGerald and Lorentz. In neither case was a strict, longitudinal length contraction hypothesis invoked, as is commonly supposed. Lorentz postulated, particularly in 1895, any one of a certain family of possible deformation effects for rigid bodies in motion, including purely transverse alteration, and expansion as well as contraction; FitzGerald may well have had the same family in mind. A careful analysis o
Negative / Null Result ReportOpen accessComputer Science
Chuan-Ren Chen, Yu-Kuang Chu, Ho-Chin Tsai · 2014 · arXiv
Even though the sensitivity of direct dark matter search experiments reach the level about $10^{-45}~{\rm cm}^2$, there is no confident signal of dark matter been observed. We point out that, if dark matter is a vector boson, the null result in direct dark matter search experiments may due to the destructive effects in dark-matter-nucleon elastic scattering. We illustrate the scenario using a modified Higgs portal model that includes exotic quarks. The significant cancellation can occur for certain mass gap between heavy quark and dark matter. As a result, the spin-independent dark-matter-nucl
Negative / Null Result ReportOpen accessComputer Science
Jaron Maene, Mingxiao Li, Marie-Francine Moens · 2021 · arXiv
The lottery ticket hypothesis states that sparse subnetworks exist in randomly initialized dense networks that can be trained to the same accuracy as the dense network they reside in. However, the subsequent work has failed to replicate this on large-scale models and required rewinding to an early stable state instead of initialization. We show that by using a training method that is stable with respect to linear mode connectivity, large networks can also be entirely rewound to initialization. Our subsequent experiments on common vision tasks give strong credence to the hypothesis in Evci et a
Negative / Null Result ReportOpen accessPhysics
Guillermo Gonzalez · 2005 · arXiv
Results from detailed spectroscopic analyses of stars hosting massive planets are employed to search for trends between abundances and condensation temperatures. The elements C, S, Na, Mg, Al, Ca, Sc, Ti, V, Cr, Mn, Fe, Ni and Zn are included in the analysis of 64 stars with planets and 33 comparison stars. No significant trends are evident in the data. This null result suggests that accretion of rocky material onto the photospheres of stars with planets is not the primary explanation for their high metallicities. However, the differences between the solar photospheric and meteoritic abundance
Negative / Null Result ReportOpen accessComputer Science
Gabriel Di Lemos Santiago Lima, Rafael Chaves Souto Araujo, Sebastiao Alves Dias · 2009 · arXiv
We consider chiral fermions interacting minimally with abelian and non-abelian gauge fields. Using a path integral approach and exploring the consequences of a mechanism of symmetry restoration, we show that the gauge anomaly has null expectation value in the vacuum for both cases (abelian and non-abelian). We argue that the same mechanism has no possibility to cancel the chiral anomaly, what eliminates competition between chiral and gauge symmetry at full quantum level. We also show that the insertion of the gauge anomaly in arbitrary gauge invariant correlators gives a null result, which poi
Negative / Null Result ReportOpen accessPhysics
M. Rybak, L. Lemsom, A. Lundgren et al. · 2023 · arXiv
We report a non-detection of the [OI] 63-um emission line from the z = 6.03 galaxy G09.83808 using ALMA Band 9 observations, refuting the previously claimed detection with APEX by (Rybak et al. 2020); the new upper limit on the [OI] 63-um flux is almost 20-times lower. [OI] 63-um line could be a powerful tracer of neutral gas in the Epoch of Reionisation: yet our null result shows that detecting [OI] 63-um from z$\geq$6 galaxies is more challenging than previously hypothesised.
Negative / Null Result ReportOpen accessPhysics
K. E. Belle, N. Sanghi, S. B. Howell et al. · 2004 · arXiv
Circumbinary (CB) disks have been proposed as a mechanism to extract orbital angular momentum from cataclysmic variables (CVs) during their evolution. As proposed by Taam & Spruit, these disks extend outwards to several a.u. and should be detected observationally via their infrared flux or by absorption lines in the ultraviolet spectra of the CV. We have made use of archival HST/STIS spectra as well as our own near-IR imaging to search for observational evidence of such CB disks in seven CVs. Based on the null result, we place an upper limit on the column density of the disk of N_H~10^17 cm^-2
Negative / Null Result ReportOpen accessPhysics
Davide Bigoni, Diego Misseroni, Andrea Piccolroaz · 2026 · arXiv
Two equal and opposite distributed dead loads are applied orthogonally to the axis of an elastic rod in its rectilinear reference configuration, one at the extrados and the other at the intrados, such that the resultant applied force per unit length is uniformly zero. In this configuration, the rod is subjected to a transverse (tensile or compressive) stress, which is usually believed to have no significant effect on the structural response and has therefore not been considered so far. Contrary to this common belief, the asymptotic behavior of an incrementally deformed elastic layer and three
Negative / Null Result ReportOpen accessComputer Science
J. Adams · 1997 · arXiv
We searched for the appearance of pi+pi- pairs with invariant mass greater than 648 MeV in a neutral beam. Such an observation could signify the decay of a long-lived light neutral particle. We find no evidence for this decay. Our null result severely constrains the existence of an R0 hadron, which is the lightest bound state of a gluon and a light gluino, and thereby also the possibility of a light gluino. Depending on the photino mass, we exclude the R0 in the mass and lifetime ranges of 1.2 -- 4.6 GeV and 2E-10 -- 7E-4 seconds, respectively. (To Appear in Phys. Rev. Lett.)
Negative / Null Result ReportOpen accessPhysics
J. -M. Miralles, T. Erben, H. Haemmerle et al. · 2003 · arXiv
Following the detection of a cosmic shear signal at the 30'' scale using archival parallel data from the STIS CCD camera onboard HST in Haemmerle et al. (2002), we analyzed a larger data set obtained from an HST GO pure parallel program. Although this data set is considerably larger than the one analyzed previously, we do not obtain a significant detection of the cosmic shear signal. The potential causes of this null result are the multiple systematics that plague the STIS CCD data, and in particular the degradation of the CCD charge transfer efficiency after 4 years in space.
Negative / Null Result ReportOpen accessPhysics
Jean Paul Mbelek, Herman J. Mosquera Cuesta · 2007 · arXiv
It has been claimed that during the late time history of our universe, the fine structure constant of electromagnetism, $α$, has been increasing (Webb et al. 2001; Murphy et al. 2003). The conclusion is achieved after looking at the separation between lines of ions like CIV, MgII, SiII, FeII, among others in the absorption spectra of very distant quasars, and comparing them with their counterparts obtained in the laboratory. However, in the meantime, other teams has claimed either a null result or a decreasing $α$ with respect to the cosmic time (Chand et al. 2004; Levshakov et al. 2004). Also
Negative / Null Result ReportOpen accessComputer Science
Yuta Hamada, Masatoshi Yamada · 2016 · arXiv
The null result in the LHC may indicate that the standard model is not drastically modified up to very high scales such as the GUT/string scale. Having this in the mind, we suggest a novel leptogenesis scenario realized in the false vacuum of the Higgs field. If the Higgs field develops a large vacuum expectation value in the early universe, a lepton number violating process is enhanced, which we use for baryogenesis. To demonstrate the scenario, several models are discussed. For example, we show that the observed baryon asymmetry is successfully generated in the standard model with higher-dim
Negative / Null Result ReportOpen accessComputer Science
R. C. Verma, M. P. Khanna · 1995 · arXiv
According to the Coleman-Glashow null theorem if all the symmetry breaking effects belong to the same regular representation (octet in the case of SU(3) and {\bf 15} in the case of SU(4)) and are generated in a tadpole type mechanism, the strangeness changing (charm changing) weak transitions generated through the S$_{6}$ (S$_{9}$) tadpole must vanish. Exploiting this null result, we find relations between the BBP coupling constants which allow us to write the coupling constants in terms of two parameters and baryon masses. Fixing these two parameters ( $g_{NNπ}$ and $g_{ΛΣπ}$) from experiment
Negative / Null Result ReportOpen accessComputer Science
C. Giunti · 1998 · arXiv
Inspired by the recent proposal by Feldman and Cousins of a ``unified approach to the classical statistical analysis of small signals'' based on a choice of ordering in Neyman's construction of classical confidence intervals, I propose a new ordering principle for the classical statistical analysis of Poisson processes with background which minimizes the effect on the resulting confidence intervals of the observation of less background events than expected. The new ordering principle is applied to the calculation of the confidence region implied by the recent null result of the KARMEN neutrino
