@unpublished{kedia_o'shaughnessy_wade_yelikar_2024, title={Exploring hidden priors when interpreting gravitational wave and electromagnetic probes of the nuclear equation of state}, journal={arXiv e-prints}, author={Kedia, Atul and O'Shaughnessy, Richard and Wade, Leslie and Yelikar, Anjali}, year={2024}, month={May} }
 @unpublished{peng_ristić_kedia_o'shaughnessy_fontes_fryer_korobkin_mumpower_villar_wollaeger_2024, title={Kilonova Light-Curve Interpolation with Neural Networks}, DOI={10.48550/arXiv.2402.05871}, abstractNote={Kilonovae are the electromagnetic transients created by the radioactive decay of freshly synthesized elements in the environment surrounding a neutron star merger. To study the fundamental physics in these complex environments, kilonova modeling requires, in part, the use of radiative transfer simulations. The microphysics involved in these simulations results in high computational cost, prompting the use of emulators for parameter inference applications. Utilizing a training set of 22248 high-fidelity simulations, we use a neural network to efficiently train on existing radiative transfer simulations and predict light curves for new parameters in a fast and computationally efficient manner. Our neural network can generate millions of new light curves in under a minute. We discuss our emulator's degree of off-sample reliability and parameter inference of the AT2017gfo observational data. Finally, we discuss tension introduced by multi-band inference in the parameter inference results, particularly with regard to the neural network's recovery of viewing angle.}, journal={arXiv e-prints}, author={Peng, Yinglei and Ristić, Marko and Kedia, Atul and O'Shaughnessy, Richard and Fontes, Christopher J. and Fryer, Chris L. and Korobkin, Oleg and Mumpower, Matthew R. and Villar, V. Ashley and Wollaeger, Ryan T.}, year={2024}, month={Feb} }
 @unpublished{collaboration_virgo collaboration_kagra collaboration_2024, title={Observation of Gravitational Waves from the Coalescence of a $2.5-4.5~M_\odot$ Compact Object and a Neutron Star}, DOI={10.48550/arXiv.2404.04248}, abstractNote={We report the observation of a coalescing compact binary with component masses $2.5-4.5~M_\odot$ and $1.2-2.0~M_\odot$ (all measurements quoted at the 90% credible level). The gravitational-wave signal GW230529_181500 was observed during the fourth observing run of the LIGO-Virgo-KAGRA detector network on 2023 May 29 by the LIGO Livingston Observatory. The primary component of the source has a mass less than $5~M_\odot$ at 99% credibility. We cannot definitively determine from gravitational-wave data alone whether either component of the source is a neutron star or a black hole. However, given existing estimates of the maximum neutron star mass, we find the most probable interpretation of the source to be the coalescence of a neutron star with a black hole that has a mass between the most massive neutron stars and the least massive black holes observed in the Galaxy. We estimate a merger rate density of $55^{+127}_{-47}~\text{Gpc}^{-3}\,\text{yr}^{-1}$ for compact binary coalescences with properties similar to the source of GW230529_181500; assuming that the source is a neutron star-black hole merger, GW230529_181500-like sources constitute about 60% of the total merger rate inferred for neutron star-black hole coalescences. The discovery of this system implies an increase in the expected rate of neutron star-black hole mergers with electromagnetic counterparts and provides further evidence for compact objects existing within the purported lower mass gap.}, journal={arXiv e-prints}, author={Collaboration, The LIGO Scientific and Virgo Collaboration and KAGRA Collaboration}, year={2024}, month={Apr} }
 @unpublished{sänger_roy_agathos_birnholtz_buonanno_dietrich_haney_julié_pratten_steinhoff_et al._2024, title={Tests of General Relativity with GW230529: a neutron star merging with a lower mass-gap compact object}, DOI={10.48550/arXiv.2406.03568}, abstractNote={On 29 May 2023, the LIGO Livingston observatory detected the gravitational-wave signal GW230529_181500 from the merger of a neutron star with a lower mass-gap compact object. Its long inspiral signal provides a unique opportunity to test General Relativity (GR) in a parameter space previously unexplored by strong-field tests. In this work, we performed parameterized inspiral tests of GR with GW230529_181500. Specifically, we search for deviations in the frequency-domain GW phase by allowing for agnostic corrections to the post-Newtonian coefficients. We performed tests with the Flexible Theory Independent (FTI) and Test Infrastructure for General Relativity (TIGER) frameworks using several quasi-circular waveform models that capture different physical effects (higher modes, spins, tides). We find that the signal is consistent with GR for all deviation parameters. Assuming the primary object is a black hole, we obtain particularly tight constraints on the dipole radiation at $-1$PN order of $|\delta\hat{\varphi}_{-2}| \lesssim 8 \times 10^{-5}$, which is a factor $\sim17$ times more stringent than previous bounds from the neutron star--black hole merger GW200115_042309, as well as on the 0.5PN and 1PN deviation parameters. We discuss some challenges that arise when analyzing this signal, namely biases due to correlations with tidal effects and the degeneracy between the 0PN deviation parameter and the chirp mass. To illustrate the importance of GW230529_181500 for tests of GR, we mapped the agnostic $-1$PN results to a class of Einstein-scalar-Gauss-Bonnet (ESGB) theories of gravity. We also conducted an analysis probing the specific phase deviation expected in ESGB theory and obtain an upper bound on the Gauss-Bonnet coupling of $\ell_{\rm GB} \lesssim 0.51~\rm{M}_\odot$ ($\sqrt{\alpha_{\rm GB}} \lesssim 0.28$ km), which is better than any previously reported constraint.}, journal={arXiv e-prints}, author={Sänger, Elise M. and Roy, Soumen and Agathos, Michalis and Birnholtz, Ofek and Buonanno, Alessandra and Dietrich, Tim and Haney, Maria and Julié, Félix-Louis and Pratten, Geraint and Steinhoff, Jan and et al.}, year={2024}, month={Jun} }
 @article{fryer_hungerford_wollaeger_miller_de_fontes_korobkin_kedia_ristic_richard_2024, title={The Effect of the Velocity Distribution on Kilonova Emission}, url={https://doi.org/10.3847/1538-4357/ad1036}, DOI={10.3847/1538-4357/ad1036}, abstractNote={Abstract}, journal={The Astrophysical Journal}, author={Fryer, Chris L. and Hungerford, Aimee L. and Wollaeger, Ryan T. and Miller, Jonah M. and De, Soumi and Fontes, Christopher J. and Korobkin, Oleg and Kedia, Atul and Ristic, Marko and Richard, O’Shaughnessy}, year={2024}, month={Jan} }
 @article{ristić_o'shaughnessy_villar_wollaeger_korobkin_fryer_fontes_kedia_2023, title={Interpolated kilonova spectra models: Examining the effects of a phenomenological, blue component in the fitting of AT2017gfo spectra}, url={https://doi.org/10.1103/PhysRevResearch.5.043106}, DOI={10.1103/PhysRevResearch.5.043106}, abstractNote={In this paper, we present a simple interpolation methodology for spectroscopic time series based on conventional interpolation techniques (random forests) implemented in widely available libraries. We demonstrate that our existing library of simulations is sufficient for training, producing interpolated spectra that respond sensitively to varied ejecta parameter, postmerger time, and viewing angle inputs. We compare our interpolated spectra to the AT2017gfo spectral data and find parameters similar to our previous inferences using broadband light curves. However, the spectral observations have significant systematic short-wavelength residuals relative to our models, which we cannot explain within our existing framework. In line with previous studies, we consider the contribution of a third component as a radioactive heating source characterized by light, slow-moving, lanthanide-free ejecta with ${M}_{\mathrm{th}}=0.003\phantom{\rule{0.16em}{0ex}}{M}_{\ensuremath{\bigodot}}, {v}_{\mathrm{th}}=0.05\mathrm{c}$, and ${\ensuremath{\kappa}}_{\mathrm{th}}=1\phantom{\rule{4pt}{0ex}}{\mathrm{cm}}^{2}/\mathrm{g}$. When included as part of our radiative transfer simulations, our choice of third component reprocesses blue photons into lower energies, having the opposite effect and further accentuating the blue-underluminosity disparity in our simulations. As such, we are unable to overcome short-wavelength deficits at later times using an additional radioactive heating component, indicating the need for a more sophisticated modeling treatment.}, journal={Physical Review Research}, author={Ristić, Marko and O'Shaughnessy, Richard and Villar, V. Ashley and Wollaeger, Ryan T. and Korobkin, Oleg and Fryer, Chris L. and Fontes, Christopher J. and Kedia, Atul}, year={2023}, month={Nov} }
 @article{kedia_ristic_o'shaughnessy_yelikar_wollaeger_korobkin_chase_fryer_fontes_2023, title={Surrogate light curve models for kilonovae with comprehensive wind ejecta outflows and parameter estimation for AT2017gfo}, url={https://doi.org/10.1103/PhysRevResearch.5.013168}, DOI={10.1103/PhysRevResearch.5.013168}, abstractNote={The electromagnetic emission resulting from neutron star mergers have been shown to encode properties of the ejected material in their light curves. The ejecta properties inferred from the kilonova emission has been in tension with those calculated based on the gravitational wave signal and numerical relativity models. Motivated by this tension, we construct a broad set of surrogate light curve models derived for kilonova ejecta. The four-parameter family of two-dimensional anisotropic simulations and its associated surrogate explore different assumptions about the wind outflow morphology and outflow composition, keeping the dynamical ejecta component consistent. We present the capabilities of these surrogate models in interpolating kilonova light curves across various ejecta parameters and perform parameter estimation for AT2017gfo both without any assumptions on the outflow and under the assumption that the outflow must be representative of solar r-process abundance patterns. Our parameter estimation for AT2017gfo shows these surrogate models help alleviate the ejecta property discrepancy while also illustrating the impact of systematic modeling uncertainties on these properties, urging further investigation.}, journal={Physical Review Research}, author={Kedia, Atul and Ristic, Marko and O'Shaughnessy, Richard and Yelikar, Anjali B. and Wollaeger, Ryan T. and Korobkin, Oleg and Chase, Eve A. and Fryer, Christopher L. and Fontes, Christopher J.}, year={2023}, month={Mar} }
 @article{kedia_kim_suh_mathews_2022, title={Binary neutron star mergers as a probe of quark-hadron crossover equations of state}, url={https://doi.org/10.1103/PhysRevD.106.103027}, DOI={10.1103/PhysRevD.106.103027}, abstractNote={It is anticipated that the gravitational radiation detected in future gravitational wave (GW) detectors from binary neutron star (NS) mergers can probe the high-density equation of state (EOS). We perform the first simulations of binary NS mergers which adopt various parametrizations of the quark-hadron crossover (QHC) EOS. These are constructed from combinations of a hadronic EOS ($n_{b}<2~n_0$) and a quark-matter EOS ($n_{b}>~5~n_0$), where $n_{b}$ and $n_0$ are the baryon number density and the nuclear saturation density, respectively. At the crossover densities ($2~ n_0<n_{b}<5~ n_0$) the QHC EOSs continuously soften, while remaining stiffer than hadronic and first-order phase transition EOSs, achieving the stiffness of strongly correlated quark matter. This enhanced stiffness leads to significantly longer lifetimes of the postmerger NS than that for a pure hadronic EOS. We find a dual nature of these EOSs such that their maximum chirp GW frequencies $f_{max}$ fall into the category of a soft EOS while the dominant peak frequencies ($f_{peak}$) of the postmerger stage fall in between that of a soft and stiff hadronic EOS. An observation of this kind of dual nature in the characteristic GW frequencies will provide crucial evidence for the existence of strongly interacting quark matter at the crossover densities for QCD.}, journal={Physical Review D}, author={Kedia, Atul and Kim, Hee Il and Suh, In-Saeng and Mathews, Grant J.}, year={2022}, month={Nov} }
 @article{zlochower_brandt_diener_gabella_gracia-linares_haas_kedia_alcubierre_alic_allen_et al._2022, title={The Einstein Toolkit}, DOI={10.5281/zenodo.6588641}, journal={Zenodo}, author={Zlochower, Yosef and Brandt, Steven R. and Diener, Peter and Gabella, William E. and Gracia-Linares, Miguel and Haas, Roland and Kedia, Atul and Alcubierre, Miguel and Alic, Daniela and Allen, Gabrielle and et al.}, year={2022}, month={May} }
 @misc{wollaeger_fryer_chase_fontes_ristic_hungerford_korobkin_herring_kedia_yelikar_2021, title={Broad Grid of 2-component kilonova models}, url={https://zenodo.org/record/7335961}, DOI={10.5281/ZENODO.7335961}, abstractNote={<strong>Abstract for data in kn_sim_cube_v1.tar.gz:</strong> This dataset is a grid of multi-angle, multi-wavelength spectra from 900 2D axisymmetric, 2-component kilonova models. The masses and velocities of each component are 0.001, 0.003, 0.01, 0.03, or 0.1 M<sub>⊙</sub> and 0.05, 0.15, or 0.3 c, respectively. The models in this dataset have been described by Wollaeger et al (2021), "A Broad Grid of 2D Kilonova Emission Models" (NASA ADS link here). This dataset is also posted on the LANL CTA website. The upload is a tarball with 3 files per model: spectra (_spec_), luminosity (_lums_), and broadband magnitudes (_mags_). The model name has model properties, for example: Run_TS_dyn_all_lanth_wind1_all_md0.03_vd0.3_mw0.003_vw0.05_lums_2020-04-25.dat is a luminosity file produced on 4/25/2020 with toroidal (T) low-Ye ejecta, spherical (S) high-Ye ejecta, "Wind 1" high-Ye composition (wind1), 0.03 M<sub>⊙</sub> and 0.3c low-Ye ejecta mass and velocity, and 0.003 M<sub>⊙</sub> and 0.05c high-Ye ejecta mass and velocity. The data format is described in <strong>data_format.pdf</strong>. <strong>Abstract for data in active_learning_sims.tar.gz:</strong> This dataset is also of multi-angle, multi-wavelength spectra from 2D axisymmetric, 2-component kilonova models, but is generated by automated placement (active learning) in mass-velocity of each component, rather than being restricted to the above grid values. The models and AL placement methods have been described by Ristic et al (2022), "Interpolating Detailed Simulations of Kilonovae: Adaptive Learning and Parameter Inference Applications" (NASA ADS link here). This dataset is also posted on the LANL CTA website. The data contained in <strong>active_learning_sims.tar.gz</strong> is formatted the same way as in <strong>kn_sim_cube_v1.tar.gz</strong>, following the description in <strong>data_format.pdf</strong>. <strong>Abstract for data in active_learning_sims_v2.tgz</strong> This dataset is an updated version of <strong>active_learning_sims.tar.gz</strong>, with additional placed simulations using the active learning procedure described by Ristic et al (2022) (see NASA/ADS link above). The main difference with respect to the previous active learning set is that this release contains active learning simulations placed for all four morphologies/compositions used in the broad grid. The models are also described by Kedia et al (2022), "Surrogate light curve models for kilonovae with comprehensive wind ejecta outflows and parameter estimation for AT2017gfo" (NASA ADS link here). <strong>Abstract for surrogate_models_and_jupyter_notebooks.tgz</strong> This tarball provides four surrogate kilonova models and sample jupyter notebooks, developed by Marko Ristic, tuned to reproduce kilonova the simulation models. Each model corresponds to each of the four morphology/composition combinations. Surrogates provide multi-band output versus time and viewing angle. The models are associated with two companion papers discussing methodology of generation and application, Ristic et al (2022) and Kedia et al (2022).<br> <br> The sample notebooks provided can be used as a starting point to understand the use of these surrogates for quickly generating kilonova light curves for a desired set of input model parameters. The usual runtime of each of these jupyter notebooks is 5 to 10mins and may require installing of 2 or 3 python packages. The surrogates and sample jupyter notebooks can also be accessed at the following GitHub repository: https://github.com/markoris/surrogate_kne}, publisher={Zenodo}, author={Wollaeger, Ryan and Fryer, Christopher and Chase, Eve and Fontes, Christopher and Ristic, Marko and Hungerford, Aimee and Korobkin, Oleg and Herring, Angela and Kedia, Atul and Yelikar, Anjali}, year={2021}, month={May} }
 @unpublished{mathews_suh_lan_kedia_2021, title={Conformally flat, quasi-circular numerical simulations of the gravitational wave chirp from binary neutron star merger GW170817}, DOI={10.48550/arXiv.2103.05082}, abstractNote={The first detection of gravitational waves from the binary neutron star merger GW170817 by the LIGO-Virgo Collaboration has provided fundamental new insights into the astrophysical site for r-process nucleosynthesis and on the nature of dense neutron-star matter. The detected gravitational wave signal depends upon the tidal distortion of the neutron stars as they approach merger. We report on relativistic numerical simulations of the approach to binary merger in the conformally flat, quasi-circular orbit approximation. We show that this event serves as a calibration to the quasi-circular approximation and a confirmation of the validity of the conformally flat approximation to the three-metric. We then examine how the detected chirp depends upon the adopted equation of state. This establishes a new efficient means to constrain the nuclear equation of state in binary neutron star mergers.}, journal={arXiv e-prints}, author={Mathews, Grant J. and Suh, In-Saeng and Lan, N. Q. and Kedia, Atul}, year={2021}, month={Mar} }
 @article{kusakabe_kedia_mathews_sasankan_2021, title={Distribution function of nuclei from e± scattering in the presence of a strong primordial magnetic field}, url={https://doi.org/10.1103/PhysRevD.104.123534}, DOI={10.1103/PhysRevD.104.123534}, abstractNote={The amplitude of the primordial magnetic field (PMF) is constrained from observational limits on primordial nuclear abundances. Within this constraint, it is possible that nuclear motion is regulated by Coulomb scattering with electrons and positrons (e’s), while e’s are affected by a PMF rather than collisions. For example, at a temperature of 10 K, thermal nuclei typically experience ∼ 10 scatterings per second that are dominated by very small angle scattering leading to minuscule changes in the nuclear kinetic energy of order O(1) eV. In this paper the upper limit on the effects of a possible discretization of the e momenta by the PMF on the nuclear momentum distribution is estimated under the extreme assumptions that the momentum of the e is relaxed before and after Coulomb scattering to Landau levels, and that during Coulomb scattering the PMF is neglected. This assumption explicitly breaks the time reversal invariance of Coulomb scattering, and the Maxwell-Boltzmann distribution is not a trivial steady state solution of the Boltzmann equation under these assumptions. We numerically evaluate the collision terms in the Boltzmann equation, and show that the introduction of a special direction in the e distribution by the PMF generates no directional dependence of the collisional destruction term of nuclei. Large anisotropies in the nuclear distribution function are then constrained from big bang nucleosynthesis. Ultimately, we conclude that a PMF does not significantly affect the isotropy or BBN.}, journal={Physical Review D}, author={Kusakabe, Motohiko and Kedia, Atul and Mathews, Grant J. and Sasankan, Nishanth}, year={2021}, month={Dec} }
 @article{kedia_sasankan_mathews_kusakabe_2021, title={Simulations of multicomponent relativistic thermalization}, url={https://doi.org/10.1103/PhysRevE.103.032101}, DOI={10.1103/PhysRevE.103.032101}, abstractNote={Multicomponent relativistic fluids have been studied for decades. However, simulating the dynamics of the particles and fluids in such a mixture has been a challenge due to the fact that such simulations are computationally expensive in three spatial dimensions. Here, we report on the development and application of a multidimensional relativistic Monte Carlo code to explore the thermalization process in a relativistic multicomponent environment in a computationally inexpensive way. As an illustration we simulate the fully relativistic three-dimensional Brownian-motion-like solution to the thermalization of a high-mass particle (proton) in a bath of relativistic low-mass particles (electrons). We follow the thermalization and ultimate equilibrium distribution of the Brownian-like particle as can happen in the cosmic plasma during big-bang nucleosynthesis. We also simulate the thermalization of energetic particles injected into the plasma as can occur, for example, by the decay of massive unstable particles during the big bang.}, journal={Physical Review E}, author={Kedia, Atul and Sasankan, Nishanth and Mathews, Grant J. and Kusakabe, Motohiko}, year={2021}, month={Mar} }
 @article{etienne_brandt_diener_gabella_gracia-linares_haas_kedia_alcubierre_alic_allen_et al._2021, title={The Einstein Toolkit}, DOI={10.5281/zenodo.4884780}, journal={Zenodo}, author={Etienne, Zachariah and Brandt, Steven R. and Diener, Peter and Gabella, William E. and Gracia-Linares, Miguel and Haas, Roland and Kedia, Atul and Alcubierre, Miguel and Alic, Daniela and Allen, Gabrielle and et al.}, year={2021}, month={May} }
 @article{sasankan_kedia_kusakabe_mathews_2020, title={Analysis of the multicomponent relativistic Boltzmann equation for electron scattering in big bang nucleosynthesis}, volume={101}, url={https://doi.org/10.1103/PhysRevD.101.123532}, DOI={10.1103/PhysRevD.101.123532}, abstractNote={Big-bang nucleosynthesis (BBN) is valuable as a means to constrain the physics of the early universe and it is the only probe of the radiation-dominated epoch. A fundamental assumption in BBN is that the nuclear velocity distributions obey Maxwell-Boltzmann (MB) statistics as they do in stars. Specifically, the BBN epoch is characterized by a dilute baryon plasma for which the velocity distribution of nuclei is mainly determined by the dominant Coulomb elastic scattering with mildly relativistic electrons. One must therefore deduce the momentum distribution for reacting nuclei from the multi-component relativistic Boltzmann equation. However, the full multi-component relativistic Boltzmann equation has only recently been analyzed and its solution has only been worked out in special cases. Moreover, a variety of schemes have been proposed that introduce non-thermal components into the BBN environment which can alter the thermal distribution of reacting nuclei. Here, we construct the relativistic Boltzmann equation in the context of BBN. We also derive a Langevin model and perform relativistic Monte-Carlo simulations which clarify the baryon distribution during BBN and can be used to analyze any relaxation from a non-thermal injection. We show by these analyses that the thermalization process leads to a nuclear distribution function that remains very close to MB statistics even during the most relativistic environment relevant to BBN. Hence, the predictions of standard BBN remain unchanged.}, number={12}, journal={Physical Review D}, publisher={American Physical Society (APS)}, author={Sasankan, Nishanth and Kedia, Atul and Kusakabe, Motohiko and Mathews, Grant J.}, year={2020}, month={Jun} }
 @inproceedings{mathews_kedia_sasankan_kusakabe_luo_kajino_yamazaki_makki_eid_2020, title={Cosmological Solutions to the Lithium Problem}, url={http://dx.doi.org/10.7566/jpscp.31.011033}, DOI={10.7566/jpscp.31.011033}, abstractNote={The abundance of primordial lithium is derived from the observed spectroscopy of metal-poor stars in the galactic halo. However, the observationally inferred abundance remains at about a factor of three below the abundance predicted by standard big bang nucleosynthesis (BBN). The resolution of this dilemma can be either astrophysical (stars destroy lithium after BBN), nuclear (reactions destroy lithium during BBN), or cosmological, i.e. new physics beyond the standard BBN is responsible for destroying lithium. Here, we overview a variety of possible cosmological solutions, and their shortcomings. On the one hand, we examine the possibility of physical processes that modify the velocity distribution of particles from the usually assumed Maxwell-Boltzmann statistics. A physical justification for this is an inhomogeneous spatial distribution of domains of primordial magnetic field strength as a means to reduce the primordial lithium abundance. Another possibility is that scattering with the mildly relativistic electrons in the background plasma alters the baryon distribution to one resembling a Fermi-Dirac distribution. We show that neither of these possibilities can adequately resolve the lithium problem. A number of alternate hybrid models are discussed including a mix of neutrino degeneracy, unified dark matter, axion cooling, and the presence of decaying and/or charged supersymmetric particles.}, booktitle={Proceedings of the 15th International Symposium on Origin of Matter and Evolution of Galaxies (OMEG15)}, publisher={Journal of the Physical Society of Japan}, author={Mathews, G. J. and Kedia, A. and Sasankan, N. and Kusakabe, M. and Luo, Y. and Kajino, T. and Yamazaki, D. and Makki, T. and Eid, M. El}, year={2020}, month={Mar} }
 @article{mathews_kedia_sasankan_kusakabe_luo_kajino_yamazaki_makki_el eid_2020, title={Cosmological solutions of the lithium problem}, journal={Memorie della Societa Astronomica Italiana}, author={Mathews, G. J. and Kedia, A. and Sasankan, N. and Kusakabe, M. and Luo, Y. and Kajino, T. and Yamazaki, D. and Makki, T. and El Eid, M.}, year={2020} }
 @article{brandt_brendal_gabella_haas_karakaş_kedia_rosofsky_schaffarczyk_alcubierre_alic_et al._2020, title={The Einstein Toolkit}, DOI={10.5281/zenodo.3866075}, journal={Zenodo}, author={Brandt, Steven R. and Brendal, Brockton and Gabella, William E. and Haas, Roland and Karakaş, Beyhan and Kedia, Atul and Rosofsky, Shawn G. and Schaffarczyk, Alois Peter and Alcubierre, Miguel and Alic, Daniela and et al.}, year={2020}, month={May} }
 @unpublished{sarkar_majumdar_pandey_kedia_sarkar_2016, title={The many scales to cosmic homogeneity: Use of multiple tracers from the SDSS}, DOI={10.48550/arXiv.1611.07915}, abstractNote={We carry out multifractal analyses of multiple tracers namely the main galaxy sample, the LRG sample and the quasar sample from the SDSS to test the assumption of cosmic homogeneity and identify the scale of transition to homogeneity, if any. We consider the behaviour of the scaled number counts and the scaling relations of different moments of the galaxy number counts in spheres of varying radius $R$ to calculate the spectrum of the Minkowski-Bouligand general dimension $D_{q} (R)$ for $-4 \leq q \leq 4$. The present analysis provides us the opportunity to study the spectrum of the generalized dimension $D_{q}(R)$ for multiple tracers of the cosmic density field over a wide range of length scales and allows us to confidently test the validity of the assumption of cosmic homogeneity. Our analysis indicates that the SDSS main galaxy sample is homogeneous on a length scales of $80\, h^{-1}\, {\rm Mpc} $ and beyond whereas the SDSS quasar sample and the SDSS LRG sample show transition to homogeneity on an even larger length scales at $\sim 150\, h^{-1}\, {\rm Mpc}$ and $\sim 230\, h^{-1}\, {\rm Mpc}$ respectively. These differences in the scale of homogeneity arise due to the effective mass and redshift scales probed by the different tracers in a Universe where structures form hierarchically. Our results reaffirm the validity of cosmic homogeneity on large scales irrespective of the tracers used and strengthens the foundations of the Standard Model of Cosmology.}, journal={arXiv e-prints}, author={Sarkar, Prakash and Majumdar, Subhabrata and Pandey, Biswajit and Kedia, Atul and Sarkar, Suman}, year={2016}, month={Nov} }