Tootfinder

a new amazing artwork recreation by Nicholas Rougeux (@…) : "Clavis Cælestis: A Synopsis of the Universe – Digital edition of Thomas Wright’s 1742 astronomical treatise" https://www.c82.net/work/?id=399

Saving or Destroying the Universe with Axion-Like Particles
Anne Mareike Galda, Matthias Neubert
https://arxiv.org/abs/2506.06426 https://

Saving or Destroying the Universe with Axion-Like Particles
Light pseudoscalar resonances that couple to the Standard Model via non-renormalizable operators, such as axions and axion-like particles (ALPs), generate contributions to the renormalization group evolution equations of couplings of dimension-4 and higher-dimensional operators. In particular, they modify the $β$-function of the Higgs quartic coupling and of SM and SMEFT parameters entering this equation, thus having an impact on the instability scale of the electroweak vacuum. We employ this …

"Science is more than a body of knowledge. It's a way of thinking, a way of skeptically interrogating the universe with a fine understanding of human fallibility. If we are not able to ask skeptical questions -- to interrogate those who tell us something is true -- to be skeptical of those in authority, then we're up for grabs for the next charlatan, political or religious, who comes ambling along."
-- Carl Sagan (Charlie Rose interview)

400 years ago #OTD the astronomer Giovanni Domenico Cassini a.k.a. #Cassini I (because they would become an astro-dynasty) was born: while #meridiana of Bologna: https://en.wikipedia.org/wiki/San_Petronio,_Bologna

The monster isn't in the machine. It's in the mirror
https://brilliantcrank.com/every-generation-discovers-the-same-monster/?ref=brilliantcrank-newsletter
via @…

From Olivier Messiaen's ‘Technique of My Musical Language':
"My freedom is total: no prohibition weighs upon me; all sounds being admitted, all modes, all rhythms, all noises, all timbres. I am a free man: the universe is mine. I gather it like a bouquet..."

Cascade Relaxation of the Gravitating Vacuum as a Generator of the Evolving Universe
V. N. Lukash (Astro Space Center, P. N. Lebedev Physical Institute, Russian Academy of Sciences, Russia), E. V. Mikheeva (Astro Space Center, P. N. Lebedev Physical Institute, Russian Academy of Sciences)
https://arxiv.org/abs/2506.03226

Cascade Relaxation of the Gravitating Vacuum as a Generator of the Evolving Universe
The cascade relaxation of a polarized vacuum in the expanding Universe is a chain of evolutionary epochs of decreasing its density with the exit of dominant fields (each in its own time) from the initial zero states to nonzero values, from the dominant scalar field in the early Universe to subsequent ones, including the $Λ$-term in the modern Universe. The cascade vacuum relaxation creates the entire observable cosmology from the Friedmann model with small perturbations of the metric with non-…

A Reassessment of the Pantheon and DES 5YR Calibration Uncertainties: Dovekie
B. Popovic, W. D. Kenworthy, M. Ginolin, A. Goobar, P. Shah, B. M. Boyd, A. Do, D. Brout, D. Scolnic, M. Vincenzi, S. Dhawan, D. O. Jones, M. Smith, M. Rigault, B. Racine, E. E. Hayes, R. Chen, P. Wiseman, L. Galbany, M. Grayling, L. LaCroix, C. Barjou-Delayre, D. Kuhn, C. Lemon

A Reassessment of the Pantheon+ and DES 5YR Calibration Uncertainties: Dovekie
Type Ia Supernovae (SNe Ia) are crucial tools to measure the accelerating expansion of the universe, comprising thousands of SNe across multiple telescopes. Accurate measurements of cosmological parameters with SNe Ia require a robust understanding and cross-calibration of the telescopes and filters. A previous cross-calibration effort, 'Fragilistic', provided 25 photometric systems, but offered no public code or ability to add new surveys. We provide an open-source cross-calibration solution, …

Traces of the evolution of cosmic void galaxies: An Integral Field Spectroscopy based analysis
Agust\'in M. Rodr\'iguez-Medrano, Dante J. Paz, Dami\'an Mast, Federico A. Stasyszyn, Andr\'es N. Ruiz
https://arxiv.org/abs/2506.07783

Traces of the evolution of cosmic void galaxies: An Integral Field Spectroscopy based analysis
Galaxies in the most underdense regions of the Universe, known as cosmic voids, exhibit astrophysical properties that suggest a distinct evolutionary path compared to galaxies in denser environments. Numerical simulations indicate that the assembly of void galaxies occurs later, leading to galaxies with younger stellar populations, low metallicities, and a high gas content in their halos, which provides the fuel to sustain elevated star formation activity. Our objective in this work is to test …

from my link log —
Dissolving the Fermi paradox.
https://arxiv.org/abs/1806.02404
saved 2025-04-18 https://dotat.at/:/U1H2Q.html

Dissolving the Fermi Paradox
The Fermi paradox is the conflict between an expectation of a high {\em ex ante} probability of intelligent life elsewhere in the universe and the apparently lifeless universe we in fact observe. The expectation that the universe should be teeming with intelligent life is linked to models like the Drake equation, which suggest that even if the probability of intelligent life developing at a given site is small, the sheer multitude of possible sites should nonetheless yield a large number of pot…

Probing QCD Confinement with Spin Entanglement
The STAR Collaboration
https://arxiv.org/abs/2506.05499 https://arxiv.org/pdf/2506.054…

Probing QCD Confinement with Spin Entanglement
Once regarded as mere emptiness, the vacuum is now understood to possess a rich and complex structure, characterized by fluctuating energy fields and a condensate of virtual quark-antiquark pairs. These pairs cause spontaneous chiral symmetry breaking, a fundamental phenomenon that is believed to generate over 99% of the mass in the visible universe. However, the precise mechanism linking the chiral symmetry breaking to the mass generation associated with quark confinement remains one of the mo…

Avalon & Electric Universe - Plant Medicine | #NowPlaying

On sums of $\mathscr{P}$-free forms under mis\`ere play
Alfie Davies, Sarah Miller, Rebecca Milley
https://arxiv.org/abs/2506.05257 https://

On sums of $\mathscr{P}$-free forms under misère play
Milley and Renault proved an interesting characterisation of invertible elements in the dead-ending universe: they are the games with no subpositions of outcome $\mathscr{P}$ (the '$\mathscr{P}$-free' games). We generalise their approach to obtain a stronger result and show in particular that the set of $\mathscr{P}$-free blocking games is closed under addition, which yields that every $\mathscr{P}$-free blocking game is invertible modulo the blocking universe. This has consequences for the inv…

Siguiendo el especial de Pulp, presentamos «Master of the Universe», canción del 2do disco de la banda, Freaks, de 1987. Un šlbum notablemente mšs denso y oscuro que el debut y que no tuvo mucho éxito por esa época.
https://open.spotify.com/track/0GoYxBhAAApHrfGERig7Y9

Magnetogenesis from Sawtooth Coupling: Gravitational Wave Probe of Reheating
Subhasis Maiti
https://arxiv.org/abs/2506.06183 https://…

Magnetogenesis from Sawtooth Coupling: Gravitational Wave Probe of Reheating
The detection of gravitational waves (GWs) by LIGO-Virgo and pulsar timing arrays (PTAs) has opened a new window into early universe cosmology. Yet, the origin of large-scale magnetic fields and the dynamics of the reheating epoch remain poorly understood. In this work, we study the generation of secondary GWs (SGWs) sourced by primordial magnetic fields produced via a Sawtooth-type coupling during reheating with a general background evolution. We show that the reheating equation of state signi…

ASKAP-EMU radio continuum detection of planetary nebula NGC 5189: the "Infinity" nebula
A. D. Asher, Z. J. Smeaton, M. D. Filipovi\'c, A. M. Hopkins, J. Th. van Loon, T. J. Galvin, L. A. Barnes
https://arxiv.org/abs/2506.06768

ASKAP-EMU radio continuum detection of planetary nebula NGC 5189: the "Infinity" nebula
We report the radio continuum detection of well known Galactic Planetary Nebula (PN) NGC 5189, observed at 943 MHz during the Australian Square Kilometre Array Pathfinder (ASKAP) Evolutionary Map of the Universe (EMU) survey. Two detections of NGC 5189 have been made during the survey, of better resolution than previous radio surveys. Both measurements of the integrated flux density are consistent with each other, at $S_{\rm 943\,MHz} = 0.33\pm0.03$ Jy, and the spectral luminosity is $L_{\rm{94…

This https://arxiv.org/abs/2505.24586 has been replaced.
initial toot: https://mastoxiv.page/@arXiv_…

All-sky search for individual Primordial Black Hole bursts with LHAASO
Primordial Black Holes~(PBHs) are hypothetical black holes with a wide range of masses that formed in the early universe. As a result, they may play an important cosmological role and provide a unique probe of the early universe. A PBH with an initial mass of approximately $10^{15}$~g is expected to explode today in a final burst of Hawking radiation. In this work, we conduct an all-sky search for individual PBH burst events using the data collected from March 2021 to July 2024 by the Water Che…

This https://arxiv.org/abs/1910.10819 has been replaced.
link: https://scholar.google.com/scholar?q=a

Universe in a rotating black hole and preferred axis
If our universe was born as a baby universe on the other side of the event horizon of a black hole existing in a parent universe, then the corresponding white hole at rest provides the absolute frame of reference in the universe. In this frame, the cosmic microwave background radiation is isotropic on large scales. If the parent black hole is rotating, then its axis of rotation becomes a preferred axis in the universe. Accordingly, the absolute frame is non-inertial, although the non-inertial f…

This https://arxiv.org/abs/2012.08151 has been replaced.
link: https://scholar.google.com/scholar?q=a

Gravitational wave constraints on the primordial black hole dominated early universe
We calculate the gravitational waves (GWs) induced by the density fluctuations due to inhomogeneous distribution of primordial black holes (PBHs) in the case where PBHs eventually dominate and reheat the universe by Hawking evaporation. The initial PBH density fluctuations are isocurvature in nature. We find that most of the induced GWs are generated right after evaporation, when the universe transits from the PBH dominated era to the radiation dominated era and the curvature perturbation start…

All the different species in the #StarTrek universe have different requirements for (bodily) comfort. An aspect only sometimes mentioned in the different series and movies. But we will look at this aspect for today's #TrekTriviaTuesday question.
As always no googling and no spoiling t…

The Internal Kinematics, Stellar Population, and Gas-phase Properties of The Pseudobulge in An Ultra-diffuse Galaxy: AGC721966
Shihong Liu, Yu Rong, Huiyuan Wang, Hong-Xin Zhang, Tie Li, Yao Yao, Zhicheng He, Teng Liu, Enci Wang, Cheng Cheng, Xu Kong
https://arxiv.org/abs/2506.07457

The Internal Kinematics, Stellar Population, and Gas-phase Properties of The Pseudobulge in An Ultra-diffuse Galaxy: AGC721966
Leveraging spectroscopic data from the Sloan Digital Sky Survey, we conduct a comprehensive analysis of the central stellar velocity dispersion, stellar population properties, star formation history, and gas-phase chemical abundances in AGC721966, a unique ultra-diffuse galaxy (UDG) harboring a pseudobulge. Our findings reveal that the pseudobulge formed in the early universe but underwent a recent episode of rejuvenated star formation. The system exhibits a mass-weighted (light-weighted) stell…

COSMOS2025 - The COSMOS-Web galaxy catalog of photometry, morphology, redshifts, and physical parameters from JWST, HST, and ground-based imaging: #COSMOSWeb Unveils Largest Look Ever Into the Deep Universe: https://cosmos.astro.caltech.edu/news/87 -> thread https://bsky.app/profile/did:plc:jffd7lmmxzgstwjoad664sz4/post/3lqungqbyys2h with more links.

marvel_partnerships: Marvel character partnerships (2018)
A network of partnerships among characters in the Marvel comic book universe. Nodes are either heroes or villains, and edges represent partnerships between such characters. The partnership network was extracted from Wikipedia pages of these characters, which indicate partnership relations with other such pages.
This network has 350 nodes and 346 edges.
Tags: Social, Fictional, Unweighted

@… Not directly a Nestflix, but not a million km away either... https://mastodon.oysta.au/@oysta/114588644020339419

Low noise flux estimate and data quality control monitoring in EUCLID-NISP cosmological survey
B. Kubik, R. Barbier, P. Calabria, A. Castera, E. Chabanat, F. Charlieu, J-C. Clemens, A. Ealet, S. Ferriol, W. Gillard, T. Maciaszek, E. Prieto, F. Schirra, A. Secroun, B. Serra, G. Smadja, A. Tilquin, J. Zoubianb
https://arxiv.org/ab…

Low noise flux estimate and data quality control monitoring in EUCLID-NISP cosmological survey
Euclid mission is designed to understand the dark sector of the universe. Precise redshift measurements are provided by H2RG detectors. We propose an unbiased method of fitting the flux with Poisson distributed and correlated data, which has an analytic solution and provides a reliable quality factor - fundamental features to ensure the goals of the mission. We compare our method to other techniques of signal estimation and illustrate the anomaly detection on the flight like detectors. Although…

Avengers: Infinity War, Losing an Election, and What Comes After
https://ift.tt/UJj5qBY
By Matthew Brake “I know what it’s like to lose. To feel so desperately that you’re right, yet to…
via Input 4 RELCFP

Avengers: Infinity War, Losing an Election, and What Comes After
By Matthew Brake “I know what it’s like to lose. To feel so desperately that you’re right, yet to fail nonetheless.” Many of us recognize this quote from the peak of the Marvel Cinematic Universe. …

A look at YouTube's changes to become viewers' preferred TV service and to appeal more to advertisers, and at creators' push into sitcoms, like Alan's Universe (Lucas Shaw/Bloomberg)
https://www.bloomberg.com/news/features/20

Well that was an interesting one to debug... My blocky DNS service was down after a cluster restart
A given #metallb speaker won’t advertise the service if:
- the service has externalTrafficPolicy=local and there are no running endpoints on the speaker’s node
To use externalTrafficPolicy=local, the tolerations on metallb pods must match the tolerations on the destination pods…

"In order to make an apple pie from scratch, you must first create the
universe."
-- Carl Sagan, Cosmos

Hot take about #StarWars #Andor:
1️⃣ It requires the viewer to pay attn to, remember & think about the story's subplots & not be an ADHD idiot
2️⃣ It makes the narrative familiar but also takes it very seriously
3️⃣ It uses the SW universe exclusively to tell a story, not t…

This https://arxiv.org/abs/2501.01860 has been replaced.
initial toot: https://mastoxiv.page/@arXiv_hepp…

Constraining eV-scale axion-like particle dark matter: insights from the M87 Galaxy
Axion-like particles (ALPs) can account for the observed dark matter (DM) of the Universe and if their masses are at the eV scale, they can decay into infrared, optical and ultraviolet photons with a decay lifetime larger than the age of the Universe.We analyze multi-wavelength data obtained from the central region of Messier 87 (M87) galaxy by several telescopes, such as, Swift, Astrosat, Kanata, Spitzer and International Ultraviolet Explorer in the infrared to ultraviolet frequencies ($\sim 2…

The Exact and Approximate Tales of Boost-Breaking Cosmological Correlators
Zhehan Qin, S\'ebastien Renaux-Petel, Xi Tong, Denis Werth, Yuhang Zhu
https://arxiv.org/abs/2506.01555

The Exact and Approximate Tales of Boost-Breaking Cosmological Correlators
Cosmological correlators offer a remarkable window into the high-energy physics governing Universe's earliest moments, with the tantalising prospect of discovering new particles. However, extracting new physics from these observables requires both precise theoretical predictions of inflationary theories and accurate, analytical templates suitable for data analysis throughout parameter and kinematic spaces. In this paper, we extend the current analytical results by computing the most general boo…

An interesting new #OpenAccess book just dropped in the #OAPEN #Library:
Wille, J. I., Andreasen, S. J., & Wille, G. (2025). How to Create a Universe. University of Westminster Press.
…

This https://arxiv.org/abs/2302.07123 has been replaced.
initial toot: https://mastoxiv.page/@ar…

On the Arrow of Time and Organized Complexity in the Universe
There is a widespread assumption that the universe in general, and the biosphere on Earth in particular, is becoming more complex over time. This study formulates this assumption as a macroscopic law, the law of increasing complexity. It hypothesizes that this macroscopic law emerges in certain open systems, such as the observable universe and the biosphere on Earth. There are two types of complexity: disorganized and organized. The complexity associated with this assumption is organized comple…

I'm baffled that this guy is a respected analyst. Yeah, an infinite number of AI agents will spend their money on content from human creators, making those humans infinitely rich. I see no flaws in this model.

This https://arxiv.org/abs/2411.07970 has been replaced.
initial toot: https://mastoxiv.page/@arXiv_…

MUltiplexed Survey Telescope: Perspectives for Large-Scale Structure Cosmology in the Era of Stage-V Spectroscopic Survey
The MUltiplexed Survey Telescope (MUST) is a 6.5-meter telescope under development. Dedicated to highly-multiplexed, wide-field spectroscopic surveys, MUST observes over 20,000 targets simultaneously using 6.2-mm pitch positioning robots within a ~5 deg$^2$ field of view. MUST aims to conduct the first Stage-V spectroscopic survey in the 2030s, mapping the 3D Universe with over 100 million galaxies and quasars, spanning from the nearby Universe to a redshift of z ~ 5.5, corresponding to approxi…

The most energetic transients - tidal disruptions of high-mass stars: #ExtremeNuclearTransients (ENTs) are the most energetic transients yet observed.

Packed up my XBOX and large TV in the basement today :-(
I don't play video games every day, but 2 or 3 days a week, my daughter, who lives in Toronto, and I will play Halo online and defend the universe from Covenant forces. It's now 22 days until the moving trucks arrive, and planning for activities each day is underway. We have to allocate time for yard maintenance, packing, and cleaning. Accompanying music choices are important...
#MyPlaylist #RandomTune
https://youtu.be/t267aQJcwjs?si=jb8_X470NFFXY6Yp

Thinking about LLMs in the context of Philip Anderson's classic paper More is Different
the reductionist hypothesis does not by any means imply a "constructionist" one: The ability to reduce everything to simple fundamental laws does not imply the ability to start from those laws and reconstruct the universe.

marvel_partnerships: Marvel character partnerships (2018)
A network of partnerships among characters in the Marvel comic book universe. Nodes are either heroes or villains, and edges represent partnerships between such characters. The partnership network was extracted from Wikipedia pages of these characters, which indicate partnership relations with other such pages.
This network has 350 nodes and 346 edges.
Tags: Social, Fictional, Unweighted

Prospects for the Detection of High-Redshift Gamma-Ray Bursts in the Era of EP and SVOM
Jun-Jie Wei, Xue-Feng Wu
https://arxiv.org/abs/2506.04709 https://

Prospects for the Detection of High-Redshift Gamma-Ray Bursts in the Era of EP and SVOM
Gamma-ray bursts (GRBs) are a promising probe of the high-redshift Universe, but their detection remains observationally challenging. In this work, we explore the detectability of high-$z$ GRBs by the Wide-field X-ray Telescope (WXT) aboard the Einstein Probe (\emph{EP}) and the coded-mask gamma-ray imager (ECLAIRs) aboard the Space-based multi-band astronomical Variable Objects Monitor (\emph{SVOM}). Using a population synthesis model calibrated to $Swift$ GRB observations, we develop a tool t…

excellent analysis of covid state of play
From Julia Doubleday.
"Each time a new wave crops up, the media scrambles to let the public know that COVID is spreading “again” ... But each time, it fails to inform the public that nearly half of COVID cases are asymptomatic, that COVID looks different in different patients, that vaccines do not prevent infections, that rapid tests have high false negative rates, and that COVID is fully airborne.
"Taken together, the virus I’m describing is much more difficult to control than the one the press presents. The press frames the virus as something that can be halted by familiarizing yourself with the symptoms, staying home once you feel sick and test positive, and avoided altogether by simply getting vaccinated or keeping ones’ distance from sick people. ...
"The misinformation that reigns in liberal spaces is not the result of accidental miscommunication. People don’t know that the virus is asymptomatic 40% of the time because there is simply no universe where that virus is controllable without an elimination strategy, or a day-to-day mitigation strategy."
#covid #misinformation #denial #CovidIsAirborne

Universe is funny sometimes. I just learned about Moka & Co today because the Maptime organizers offered everyone some and then accidentally ended up in their Ann Arbor shop mere hours later because it's one of the closest places to the Blake open past 8pm.
It's good coffee, I'm not complainin' ☕

Star Wars Outlaws allows players to operate in the criminal underworld of the Star Wars universe.
Except there’s no real crime. It’s defanged. There’s smuggling, gambling, violence. But no drug trade, and apparently no chattel slavery (which Hutts and Pykes engaged in during the period). It’s in the movies, but not appropriate for the game, I guess because it makes the characters less sympathetic?

Nearby dwarf galaxies with extreme star formation rates: a window into dwarf-galaxy evolution in the early Universe
S. Kaviraj, B. Bichang'a, I. Lazar, A. E. Watkins, G. Martin, R. A. Jackson
https://arxiv.org/abs/2506.03265

Nearby dwarf galaxies with extreme star formation rates: a window into dwarf-galaxy evolution in the early Universe
We study a sample of nearby (z~0.2) low-luminosity dwarf (10^7 MSun < M* < 10^8 MSun) galaxies which have extreme (0.1 - 3 MSun/yr) star formation rates (SFRs) for this mass regime, making them plausible analogues of dwarfs at z~5.5. We compare the properties of these analogues to control samples of 'normal' dwarfs, which reside on the star formation main sequence (SFMS) at z~0.2 and are matched in their stellar mass and redshift distributions to the analogue population. The analogue and normal…

This https://arxiv.org/abs/2504.06290 has been replaced.
initial toot: https://mastoxiv.page/@arX…

A DESI universe with time-dependent dark energy is 119 Myr younger than a LambdaCDM universe
On the basis of their redshift and Lyman-alpha measurements, the Dark Energy Spectroscopic Instrument (DESI) collaboration suggest that dark energy varies with the scale factor $a$ as $ ρ_{de}(a)={} \, a^{-3(1 + w_0 + w_a)} e^{-3 w_a (1-a)}ρ_{de,0} $ in which $w_0 = - 0.752 \pm 0.057$ and $w_a ={} - 0.86^{+0.23}_{-0.20} $. Such a DESI universe is 119 Myr younger than the LambdaCDM universe.

Differentially Private Space-Efficient Algorithms for Counting Distinct Elements in the Turnstile Model
Rachel Cummings, Alessandro Epasto, Jieming Mao, Tamalika Mukherjee, Tingting Ou, Peilin Zhong
https://arxiv.org/abs/2505.23682

Differentially Private Space-Efficient Algorithms for Counting Distinct Elements in the Turnstile Model
The turnstile continual release model of differential privacy captures scenarios where a privacy-preserving real-time analysis is sought for a dataset evolving through additions and deletions. In typical applications of real-time data analysis, both the length of the stream $T$ and the size of the universe $|U|$ from which data come can be extremely large. This motivates the study of private algorithms in the turnstile setting using space sublinear in both $T$ and $|U|$. In …

This https://arxiv.org/abs/2408.08740 has been replaced.
initial toot: https://mastoxiv.page/@arXiv_…

Anisotropic universe with anisotropic dark energy
We investigate the anisotropic parameterization of the dark energy equation of state within the framework of an axisymmetric (planar) Bianchi-I universe. Using the latest Pantheon+ Type Ia Supernova dataset, augmented by SH0ES Cepheid distance calibrators, we constrain both the equation of state for anisotropic dark energy and other standard cosmological parameters. Additionally, we examine the presence of an underlying anisotropic axis. Our analysis yields a mean anisotropic dark energy equati…

All-sky search for individual Primordial Black Hole bursts with LHAASO
Cao, Aharonian, Bai, Bao, Bastieri, Bi, Bi, Bian, Bukevich, Cai, Cao, Cao, Chang, Chang, Chen, Chen, Chen, Chen, Chen, Chen, Chen, Chen, Chen, Chen, Chen, Chen, Chen, Chen, Chen, Chen, Cheng, Cheng, Chu, Cui, Cui, Cui, Cui, Dai, Dai, Dai, , Diao, Dong, Duan, Fan, Fan, Fang, Fang, Fang, Feng, Feng, Feng, Feng, Feng, Feng, Feng, Gabici, Gao, Gao, Gao, Gao, Gao, Ge, Ge, Geng, Giacinti, Gong, Gou, Gu, Guo, Guo, Guo, Guo…

All-sky search for individual Primordial Black Hole bursts with LHAASO
Primordial Black Holes~(PBHs) are hypothetical black holes with a wide range of masses that formed in the early universe. As a result, they may play an important cosmological role and provide a unique probe of the early universe. A PBH with an initial mass of approximately $10^{15}$~g is expected to explode today in a final burst of Hawking radiation. In this work, we conduct an all-sky search for individual PBH burst events using the data collected from March 2021 to July 2024 by the Water Che…

‘c’: More Than Just Fast as We Unpack the Universe’s Master Constant
Let's dive into the universe's ultimate speed limit: the speed of light. It's a concept so fundamental that it underpins much of modern physics, yet so mind-bogglingly fast that, as you say, human intuition struggles to truly grasp it. We call it 'c', and its value in a vacuum is precisely 299,792,458 meters per second. That's not just an estimate; since 1983, the meter has been precisely defin…

Revisiting Isocurvature Bounds on the Minimal QCD Axion
Peter W. Graham, Davide Racco
https://arxiv.org/abs/2506.03348 https://arxiv.…

Revisiting Isocurvature Bounds on the Minimal QCD Axion
The QCD axion has important connections to early universe cosmology. For example, it is often said that isocurvature limits rule out a combination of high axion decay constant, $f_a$, and high inflationary Hubble scale, $H_I$. High scales are theoretically motivated, so it is important to ask how robust this constraint is. We demonstrate that this constraint is naturally evaded when the quartic coupling of the complex $U(1)_\mathrm{PQ}$-breaking field is small. In this case, $f_a$ changes from …

Parity violation in photon quasinormal modes of black holes
Sugumi Kanno, Jiro Soda, Akira Taniguchi
https://arxiv.org/abs/2506.04149 https://

Parity violation in photon quasinormal modes of black holes
Given that black holes are ubiquitous in the universe and axion-like scalar fields are potential candidates for dark energy and/or dark matter, it is natural to consider cosmological black holes endowed with axion hair. We investigate the photon quasinormal modes of a Schwarzschild black hole with axion hair where the electromagnetic field is coupled to the axion field via a Chern-Simons interaction. We derive the master equations for the electromagnetic field as a set of coupled equations for …

Wusstet ihr, dass typst so schnell ist, dass man Tetris darin implementieren kann?
Also man erstellt ein typst source file and während man seine Spielkommandos (Links, Rechts, usw. als Buchstaben in den source code eingibt, wird das Spiel live nebenbei gerendert.
https://typst.app/universe/package/soviet-matrix/

🚀 Kubernetes Meetup in Nuremberg! 🇩🇪
Join us on June 2nd for an evening of tech talks, networking, and community fun at the next CNCF Meetup!
🎤 Speakers:
🔹 Sarah Julia Kriesch – Docker vs Podman and the Universe
🔹 Philip Laine – Spegel: A Stateless OCI Registry Mirror
📍 Location: Coworking-Space Nürnberg
🕕 18:00: Doors open for networking
🕡 18:30: Talks begin
🔗 Sign up here:

This https://arxiv.org/abs/2411.09740 has been replaced.
initial toot: https://mastoxiv.page/@arXiv_…

Type Ia supernovae
Type Ia supernovae (SNe Ia) correspond to the thermonuclear explosion of a carbon-oxygen white dwarf (C-O WD) star in a binary system, triggered by the accretion of material from another star, or the merger/collision with a secondary WD. Their phenomenal luminosity -- several billion times that of the sun -- has motivated their use as cosmological distance indicators and led to the discovery of the accelerated expansion of the universe. SNe Ia are also the main producers of iron and hence play …

Photometric redshift estimation for emission line galaxies of DESI Legacy Imaging Surveys by CNN-MLP
Shirui Wei, Changhua Li, Yanxia Zhang, Chenzhou Cui, Chao Tang, Jingyi Zhang, Yongheng Zhao, Xuebing Wu, Yihan Tao, Dongwei Fan, Shanshan Li, Yunfei Xu, Maoyuan Huang, Xingyu Yang, Zihan Kang, Jinghang Shi
https://arxiv.org/abs/2…

Photometric redshift estimation for emission line galaxies of DESI Legacy Imaging Surveys by CNN-MLP
Emission Line Galaxies (ELGs) are crucial for cosmological studies, particularly in understanding the large-scale structure of the Universe and the role of dark energy. ELGs form an essential component of the target catalogue for the Dark Energy Spectroscopic Instrument (DESI), a major astronomical survey. However, the accurate selection of ELGs for such surveys is challenging due to the inherent uncertainties in determining their redshifts with photometric data. In order to improve the accurac…

Skin Deep (PC)
There's a new pirate queen in space, and she has a hit out on you, insurance commando extraordinaire Nina Pasadena. Get out there and save those cats!
TL;DR: a fun FPS stealth-ish romp with a good sense of humor and mechanics.
Skin Deep is weird, but in a good way. For some reason this universe is populated with voxel cats that crew space ships, and it's your job to get tucked away in cryosleep until pirates hijack them. Then you're woken up and h…

Cosmological Dynamics of Accelerating Model in $f(T)$ Gravity with Special Form of Deceleration Parameter
Shivank Pal, Romanshu Garg, Gyan Prakash Singh, Gauree Shanker
https://arxiv.org/abs/2506.03756

Cosmological Dynamics of Accelerating Model in $f(T)$ Gravity with Special Form of Deceleration Parameter
In this paper, the dynamical behavior of the accelerated expansion of the universe is discussed within the framework of $f(T)$ gravity for a particular form of $ f(T)=α(-T)^{n}$. Considering a redshift-dependent parameterization of the deceleration parameter as $q(z)=q_{0}+ q_{1}\left(\frac{ \ln(N+z)}{z+1}-\ln N \right)$. We have derived the Hubble parameter in terms of redshift and discussed its effect on other cosmological parameters. Using Bayesian statistical analysis and $χ^2$-minimizati…

This https://arxiv.org/abs/2308.02636 has been replaced.
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Learning from Topology: Cosmological Parameter Estimation from the Large-scale Structure
The topology of the large-scale structure of the universe contains valuable information on the underlying cosmological parameters. While persistent homology can extract this topological information, the optimal method for parameter estimation from the tool remains an open question. To address this, we propose a neural network model to map persistence images to cosmological parameters. Through a parameter recovery test, we demonstrate that our model makes accurate and precise estimates, consider…

I read "Then I Am Myself the World: What Consciousness Is and How to Expand It" by Christof Koch.
Interesting book which spends like 8 or 9 chapters detailing all the experiments which prove beyond much doubt that consciousness, and self awareness, is a thing done by a brain.
It describes how perception is a construction of a description, has a chapter called "computational mind"
And then spends the last two chapters describing why he thinks the mind can't be computed, because drugs have made him think experience is some kind of magic associated with highly interconnected causal structures.
Apparently, he thinks, once things become interconnected enough they become able to cause things independently of the physics running those connections.
Which is crazy, obviously. There's nothing causal in direct connections between neurons that isn't equally causal in modeled connections between virtual neurons.
All his evidence in the book from neural MRI scans to the effects of psychedelic drugs and symptoms of strokes and disease point to the brain simulating a virtual reality which is the basis of perception.
That simulated world in which we live is full of colour and shape and sounds and emotions and millions of mental constructs that are built to be correlated by the senses with the outside world, but are not equal to the world itself. We live in a dream constructed to correlate with reality.
But then instead of taking the next step: That consciousness itself is a property of a simulated being inside that mental model of the universe, a property which the brain simulates and applies to the virtual self that's doing the experiencing inside that model, he jumps towards some magic implying pan-psychism or that sufficiently interconnected networks become causally self-complete for some reason nobody can fathom.
Sure, colour and shape and emotions are all made up by the brain but experience can't be! For some reason.
You see in truth dualism is false, in that there is no spirit realm in which ghosts animate the matter of the body somehow.
Yet also, dualism is true, in that there is a simulated mental reality which we live in, computed by the brain in which all perception and experience are created, which is related-to but separate-from the unfolding complicated dance of energy that is the universe our bodies interact with.
People take some DMT trip, and the model of the universe emulated by their brain collapses and breaks. Their virtual simulated self inside their mind has these experiences of being one with the universe or the experience of feeling dead yet conscious or whatever, and these hippies think that the broken down simulated experience is real and reflects how consciousness is more fundamental than the atoms that make up the neurons in their brain.
Instead of realizing it shows them that their experienced universe is a simulacrum, they think they get a more direct experience of reality somehow. A consciousness more pure than any mere base atom.
"Then I am myself the world" is a great title. Everything you ever experience is created and simulated in your brain like a dream, the whole universe is inside your head. Even the fact of experience itself.
But that isn't the conclusion Koch reaches somehow, he just jumps from describing the evidence that this is so straight into ascribing super-causal magic consciousness to particular arrangements of atoms that integrated information theory suggest have high correlation, and thinks therefore conciousness is itself the entire universe.
Ah well, fun book. I like arguing in my head with authors that are wrong.
#reading #books #consciousness #thenIAmMyselfTheWorld

The Impact of Cluster Mergers on Galaxy Properties
O\u{g}uzhan \c{C}ak{\i}r, Matt S. Owers, Lucas C. Kimmig, Paul Nulsen, Mina Pak, Gabriella Quattropani, Warrick J. Couch
https://arxiv.org/abs/2506.04799

The Impact of Cluster Mergers on Galaxy Properties
Being the most energetic events in the known universe, the impact of galaxy cluster mergers on the properties of the resident galaxies has yet to be well-understood. In this paper, we investigate the effects of merging environments on star formation in nearby clusters ($0.04

It's not all that often that we learn about the family of all the different characters in the #StarTrek universe. But let's look at such an instance for today's #TrekTriviaTuesday question.
As always no googling and no spoiling the answer for others. Please boost after voting!…

Fast Luminous Extragalactic Transients in the VLA Sky Survey: Implications for the rates of Accretion-Induced Collapse Events, Fast Blue Optical Transients and Gamma Ray Burst Afterglows
Kritti Sharma, Vikram Ravi, Dillon Z. Dong, Gregg Hallinan, Casey Law, Delina Levine, Jean J. Somalwar, Jessie Miller, Nikita Kosogorov, Steven T. Myers
https://

Fast Luminous Extragalactic Transients in the VLA Sky Survey: Implications for the rates of Accretion-Induced Collapse Events, Fast Blue Optical Transients and Gamma Ray Burst Afterglows
Radio wavelengths offer a unique window into high-energy astrophysical phenomena that may be obscured or too rapidly evolving to be captured at other wavelengths. Leveraging data from the Very Large Array Sky Survey, we perform a systematic search for fast, luminous transients with characteristic timescales $\lesssim 3$ years in the nearby universe ($z \leq 0.3$). We report the discovery of five such transients, and classify them based on their synchrotron emission energetics and host galaxy pr…

This https://arxiv.org/abs/2310.18397 has been replaced.
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Detectable and defect-free dark photon dark matter
Ultralight dark photons are compelling dark matter candidates, but their allowed kinetic mixing with the Standard Model photon is severely constrained by requiring that the dark photons do not collapse into a cosmic string network in the early Universe. Direct detection in minimal production scenarios for dark photon dark matter is strongly limited, if not entirely excluded; discovery of sub-meV dark photon dark matter would therefore point to a nonminimal dark sector. We describe a model that …

Insights in $f(Q)$ cosmology: the relevance of the connection
Ismael Ayuso, Mariam Bouhmadi-L\'opez, Che-Yu Chen, Xiao Yan Chew, Konstantinos Dialektopoulos, Yen Chin Ong
https://arxiv.org/abs/2506.03506

Insights in $f(Q)$ cosmology: the relevance of the connection
We explore the role of the affine connection in $f(Q)$ gravity, a modified theory where gravity is governed by non-metricity within the symmetric teleparallel framework. Although the connection is constrained to be flat and torsionless, it is not uniquely determined by the metric, allowing for multiple physically distinct formulations. We analyze three such connections compatible with a homogeneous and isotropic universe to show that they yield markedly different cosmological dynamics, even und…

Model selection using the HII galaxy Hubble diagram
Jun-Jie Wei, Fulvio Melia
https://arxiv.org/abs/2506.04819 https://arxiv.org/pdf/…

Model selection using the HII galaxy Hubble diagram
The proposal to use HII galaxies (HIIGx) and giant extragalactic HII regions (GEHR) as standard candles to construct the Hubble diagram at redshifts beyond the current reach of Type Ia supernovae has gained considerable support recently with the addition of five new HIIGx discovered by JWST. The updated sample of 231 sources now extends the redshift range of these objects to $z\sim 7.5$, mapping the Universe's expansion over $95\%$ of its current age. In this {\it Letter} we use these sources f…

On the entropy of the massive conformal gravity universe
F. F. Faria
https://arxiv.org/abs/2505.17171 https://arxiv.org/pdf/2505.1717…

On the entropy of the massive conformal gravity universe
We find that the total entropy of the massive conformal gravity universe is an increasing function of time, and therefore the cosmological model of the theory passes the generalized second law of thermodynamics test.

Mergers and Recoil in Triple Massive Black Hole Systems from Illustris
Pranav Satheesh, Laura Blecha, Luke Zoltan Kelley
https://arxiv.org/abs/2506.04369 h…

Mergers and Recoil in Triple Massive Black Hole Systems from Illustris
Massive black hole binaries (MBHBs) form through galaxy mergers and are among the loudest sources of gravitational waves (GWs) in the universe. If the binary inspiral time is long, a subsequent galaxy merger can introduce a third black hole, forming a triple system. In the Illustris cosmological simulation, 6% of MBHBs form such triples at parsec scales, where strong three-body interactions are likely. We apply results from numerical simulations of triple MBHs to strong triples identified in Il…

This https://arxiv.org/abs/2502.04053 has been replaced.
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Proof of principle for a light dark matter search with low-energy positron beams at NA64
Thermal light dark matter (LDM) with particle masses in the 1 MeV - 1 GeV range could successfully explain the observed dark matter abundance as a relic from the primordial Universe. In this picture, a new feeble interaction acts as a "portal" between the Standard Model and LDM particles, allowing for the exploration of this paradigm at accelerator experiments. In the last years, the "missing energy" experiment NA64e at CERN SPS (Super Proton Synchrotron) has set world-leading constraints in th…

This https://arxiv.org/abs/2410.14774 has been replaced.
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Experimental targets for dark photon dark matter
Ultralight dark photon dark matter features distinctive cosmological and astrophysical signatures and is also supported by a burgeoning direct-detection program searching for its kinetic mixing with the ordinary photon over a wide mass range. Dark photons, however, cannot necessarily constitute the dark matter in all of this parameter space. In minimal models where the dark photon mass arises from a dark Higgs mechanism, early-Universe dynamics can easily breach the regime of validity of the lo…

Global Kinetic Simulations of Monster Shocks and Their Emission
Dominic Bernardi, Yajie Yuan, Alexander Y. Chen
https://arxiv.org/abs/2506.04175 https://…

Global Kinetic Simulations of Monster Shocks and Their Emission
Fast magnetosonic waves are one of the two low-frequency plasma modes that can exist in a neutron star magnetosphere. It was recently realized that these waves may become nonlinear within the magnetosphere and steepen into some of the strongest shocks in the universe. These shocks, when in the appropriate parameter regime, may emit GHz radiation in the form of precursor waves. We present the first global Particle-in-Cell simulations of the nonlinear steepening of fast magnetosonic waves in a di…

ViT-based Local Volume dwarf galaxy Identificationin (VIDA) in the CSST survey
Han Qu, Zhen Yuan, Chengliang Wei, Chao Liu, Jiang Chang, Guoliang Li, Nicolas F. Martin, Chaowei Tsai, Shi Shao, Yu Luo, Ran Li, Xi Kang, Xiangxiang Xue, Zhou Fan
https://arxiv.org/abs/2506.04361

ViT-based Local Volume dwarf galaxy Identificationin (VIDA) in the CSST survey
Identifying dwarf galaxies within the Local Volume is crucial for constraining the luminosity function of satellite galaxies in the nearby universe. We report the detection capabilities of dwarf galaxies within the Local Volume using the Chinese Space Station Telescope (CSST). Based on the simulated imaging data of CSST, we develop a detection and classification pipeline that combines traditional image-based search techniques with advanced machine learning classification models. The simulated L…

The Multiverse: a Philosophical Introduction
Jeremy Butterfield
https://arxiv.org/abs/2505.23639 https://arxiv.org/pdf/2505.23639

The Multiverse: a Philosophical Introduction
This book is a philosopher's introduction to the idea that our universe is just one of many universes. I present and assess three versions of the idea: one version from philosophy, and two from physics. In short, they are: all the logically possible worlds; all the branches of the quantum state, in an Everettian interpretation of quantum theory; and all the bubbles of inflationary cosmology. For each proposal, I choose one main philosophical question to discuss in depth. They are, respectively:…

This https://arxiv.org/abs/2408.09964 has been replaced.
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Extended $δN$ formalism: Nonspatially Flat Separate Universe Approach
The $δN$ formalism is a powerful approach to compute non-linearly the large-scale evolution of the comoving curvature perturbation $ζ$. It assumes a set of FLRW patches that evolve independently, but in doing so, all the gradient terms are discarded, which are not negligibly small in models beyond slow-roll. In this Letter, we extend the formalism to capture these gradient corrections by encoding them in a homogeneous-spatial-curvature contribution assigned to each FLRW patch. For a concrete …

Expansion-contraction duality breaking in a Planck-scale sensitive cosmological quantum simulator
S. Mahesh Chandran, Uwe R. Fischer
https://arxiv.org/abs/2506.02719

Expansion-contraction duality breaking in a Planck-scale sensitive cosmological quantum simulator
We propose the experimental simulation of cosmological perturbations governed by a Planck-scale induced Lorentz violating dispersion, aimed at distinguishing between early-universe models with similar power spectra. Employing a novel variant of the scaling approach for the evolution of a Bose-Einstein condensate with both contact and dipolar interactions, we show that scale invariance, and in turn, the duality of the power spectrum is broken at large momenta for an inflating gas, and at small m…

Parity solves the Strong CP problem
Ravi Kuchimanchi
https://arxiv.org/abs/2506.01911 https://arxiv.org/pdf/2506.01911

Parity solves the Strong CP problem
A recent paper "What can solve the strong CP problem?" goes counter to conventional wisdom by arguing that the universe was in an initial state that combines different eigenstates of $θ$ (of the theta vacuum of QCD), and asserts that for such an initial state, axionless solutions to the Strong CP Problem based on P and CP symmetries will not work. We discuss the nature of the theta vacuum in light of this work, and find that the conventional framing and solutions based on P and CP symmetries a…

A Correlation Between FRB Dispersion Measure and Foreground Large-Scale Structure
Maryam Hussaini, Liam Connor, Ralf M. Konietzka, Vikram Ravi, Jakob Faber, Kritti Sharma, Myles Sherman
https://arxiv.org/abs/2506.04186

A Correlation Between FRB Dispersion Measure and Foreground Large-Scale Structure
The distribution of baryons in the Universe remains a fundamental open question in astronomy, and the dispersion measure (DM) of Fast Radio Bursts (FRBs) serves as a valuable tool for probing this cosmic gas. We investigate the impact of the foreground cosmic web on FRB DMs using 61 localized FRBs and public galaxy catalogs. We test for the large-scale structure's impact on cosmological DM using two methods. First, we searched for a correlation between galaxy number density along the line of si…

This https://arxiv.org/abs/2503.07718 has been replaced.
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Deciphering the Sources of Cosmic Neutrinos
More than a decade ago, the IceCube Neutrino Observatory discovered a diffuse flux of 10 TeV-10 PeV neutrinos from our Universe. This flux of unknown origin most likely emanates from an extragalactic population of neutrino sources, which are individually too faint to appear as bright emitters. We review constraints on extragalactic neutrino source populations based on the non-detection of the brightest neutrino source. Extending previous work, we discuss limitations of source populations based …

The galaxy-AGN scaling relations over 13 billion years in SHARK v2.0 (I): SMBH masses
Mat\'ias Bravo, Claudia del P. Lagos, Katy L. Proctor, \'Angel Chandro-G\'omez, Chris Power
https://arxiv.org/abs/2506.03354

The galaxy-AGN scaling relations over 13 billion years in SHARK v2.0 (I): SMBH masses
The presence of strong correlations between super-massive black hole (SMBH) masses and galaxy properties like stellar mass have been well-established in the local Universe, but how these scaling relations evolve with cosmic time is yet to be settled in both observations and theoretical models. Recent works have also highlighted the role of galaxy morphology on the scatter of the SMBH-galaxy mass scaling relations, while the impact of other galaxy properties remains poorly studied, like the role…

This https://arxiv.org/abs/2404.07249 has been replaced.
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PolyBin3D: A Suite of Optimal and Efficient Power Spectrum and Bispectrum Estimators for Large-Scale Structure
By measuring, modeling and interpreting cosmological datasets, one can place strong constraints on models of the Universe. Central to this effort are summary statistics such as power spectra and bispectra, which condense the high-dimensional data into low-dimensional representations. In this work, we introduce a modern set of estimators for computing such statistics from three-dimensional clustering data, and provide a flexible Python/Cython implementation; PolyBin3D. Working in a maximum-likel…

This https://arxiv.org/abs/2412.20091 has been replaced.
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Gamma-Ray Burst Light Curve Reconstruction: A Comparative Machine and Deep Learning Analysis
Gamma-Ray Bursts (GRBs), observed at large redshifts, are probes of the evolution of the Universe and can be used as cosmological tools. To this end, we need tight (with small dispersion) correlations among key parameters. To reduce such a dispersion, we will mitigate gaps in light curves (LCs), including the plateau region, key to building the two-dimensional Dainotti relation between the end time of plateau emission (Ta) to its luminosity (La). We reconstruct LCs using nine models: Multi-Laye…

This https://arxiv.org/abs/2402.18306 has been replaced.
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Calibration requirement for Epoch of Reionization 21-cm signal observation -- III. Bias and variance in uGMRT ELAIS-N1 field power spectrum
Power spectrum of \HI 21-cm radiation is one of the promising probes to study large scale structure of the universe and understand galaxy formation and evolution. The presence of foregrounds, that are orders of magnitude larger in the same frequency range of the redshifted 21-cm signal has been one of the largest observational challenges. The foreground contamination also hinders the calibration procedures and introduces residual calibration errors in the interferometric data. It has been shown…

An independent estimate of H(z) at z = 0.5 from the stellar ages of brightest cluster galaxies
S. Ilani Loubser, Adebusola B. Alabi, Matt Hilton, Yin-Zhe Ma, Xin Tang, Narges Hatamkhani, Catherine Cress, Rosalind E. Skelton, S. Andile Nkosi
https://arxiv.org/abs/2506.03836

An independent estimate of H(z) at z = 0.5 from the stellar ages of brightest cluster galaxies
Several cosmological observations (e.g., Cosmic Microwave Background (CMB), Supernovae Type Ia, and local distance ladder measurements such as Cepheids) have been used to measure the global expansion rate of the Universe, i.e., the Hubble constant, $H_{0}$. However, these precision measurements have revealed tensions between different probes that are proving difficult to solve. Independent, robust techniques must be exploited to validate results or mitigate systematic effects. We use the Cosmic…

This https://arxiv.org/abs/2412.09699 has been replaced.
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Neutrinos from explosive transients at the dawn of multi-messenger astronomy
With the advent of time-domain astronomy and the game-changing next generation of telescopes, we have unprecedented opportunities to explore the most energetic events in our Universe through electromagnetic radiation, gravitational waves, and neutrinos. These are elementary particles, which exist in three different flavors and change the latter as they propagate in the dense core of astrophysical sources as well as en route to Earth. To capitalize on existing and upcoming multi-messenger opport…

This https://arxiv.org/abs/2505.16380 has been replaced.
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On the Identification of Exotic Compact Binaries with Gravitational Waves: a Phenomenological approach
Gravitational wave (GW) astronomy has been hailed as a gateway to discovering unexpected phenomena in the universe. Over the last decade there have been close to one hundred GW observations of compact-binary mergers. While these signals are largely consistent with mergers of binary black holes, binary neutron stars, or black hole-neutron star systems, some events suggest the intriguing possibility of binaries involving exotic compact objects (ECOs). Identifying and characterising an ECO merger …

This https://arxiv.org/abs/2310.07661 has been replaced.
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Constraints on Bianchi-I type universe with SH0ES anchored Pantheon+ SNIa data
We study the Bianchi-I cosmological model motivated by signals of statistical isotropy violation seen in cosmic microwave background (CMB) observations and others. To that end, we consider various kinds of anisotropic matter that source anisotropy in our model, specifically Cosmic strings, Magnetic fields, Domain walls and Lorentz violation generated magnetic fields. These anisotropic matter sources, taking one at a time, are studied for their co-evolution with standard model (isotropic) source…

This https://arxiv.org/abs/2503.14460 has been replaced.
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Low-Metallicity Star Formation Survey in Sh2-284 (LZ-STAR). I. Ordered massive star formation in the outer Galaxy
Star formation is a fundamental, yet poorly understood, process of the Universe. It is important to study how star formation occurs in different galactic environments. Thus, here, in the first of a series of papers, we introduce the Low-Metallicity Star Formation (LZ-STAR) survey of the Sh2-284 (hereafter S284) region, which, at $Z\sim 0.3-0.5Z_\odot$, is one of the lowest-metallicity star-forming regions of our Galaxy. LZ-STAR is a multi-facility survey, including observations with {\it JWST},…

This https://arxiv.org/abs/2406.06635 has been replaced.
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The Hybrid Euclidean-Lorentzian Universe: Stability Considerations and the Point of Transition
TThe limited velocity implied by Lorentzian signature, prevents the universe to reach thermodynamic equilibrium implied by the CMB. Rapid expansion can occur by following Hawking and assuming a primordial Euclidean metric, in which case velocity is not limited and thermalization and rapid expansion are derived without the need to assume an ad-hoc field. Moreover, a mathematical model was given regarding the development of current Lorentzian space-time from the early Euclidean space-time in whic…

This https://arxiv.org/abs/2503.21368 has been replaced.
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The Jiutian simulations for the CSST extra-galactic surveys
We provide an overview of the Jiutian simulations, a hybrid simulation suite for the China Space Survey Telescope (CSST) extragalactic surveys. It consists of four complementary modules: the primary runs with high resolutions with the fiducial concordance cosmology, the emulator runs exploring the parameter uncertainties around the fiducial cosmology, the reconstruction runs intended for recovering the observed Universe position by position, and the extension runs employing extended cosmologies…

A White Paper on The Multi-Messenger Science Landscape in India
Samsuzzaman Afroz, Sanjib Kumar Agarwalla, Dipankar Bhattacharya, Soumya Bhattacharya, Subir Bhattacharyya, Varun Bhalerao, Debanjan Bose, Chinmay Borwanker, Ishwara Chandra C. H., Aniruddha Chakraborty, Indranil Chakraborty, Sovan Chakraborty, Debarati Chatterjee, Varsha Chitnis, Moon Moon Devi, Sanjeev Dhurandhar, Amol Dighe, Bitan Ghosal, Sourendu Gupta, Arpan Hait, Md Emanuel Hoque, Pratik Majumdar, Nilmani Mathur, Har…

A White Paper on The Multi-Messenger Science Landscape in India
The multi-messenger science using different observational windows to the Universe such as Gravitational Waves (GWs), Electromagnetic Waves (EMs), Cosmic Rays (CRs), and Neutrinos offer an opportunity to study from the scale of a neutron star to cosmological scales over a large cosmic time. At the smallest scales, we can explore the structure of the neutron star and the different energetics involved in the transition of a pre-merger neutron star to a post-merger neutron star. This will open up a…

Nonminimal infrared gravitational reheating in light of ACT
Ayan Chakraborty, Debaprasad Maity, Rajesh Mondal
https://arxiv.org/abs/2506.02141 https://

Nonminimal infrared gravitational reheating in light of ACT
Inflation is known to produce large infrared scalar fluctuations. Further, if a scalar field $(χ)$ is non-minimally coupled with gravity through $ξχ^2 R$, those infrared modes experience \textit{tachyonic instability} during and after inflation. Those large non-perturbative infrared modes can collectively produce hot Big Bang universe upon their horizon entry during the post-inflationary period. We indeed find that for reheating equation of state (EoS), $w_ϕ > 1/3$, and coupling strength, $…

Chicago-Carnegie Hubble Program (CCHP) A Multi-Wavelength Search for the Effects of Metallicity on the Cepheid Distance Scale. Part II: Theoretical Models and Synthetic Spectra
Barry F. Madore, Wendy L. Freedman, Kayla Owens
https://arxiv.org/abs/2506.01188

Chicago-Carnegie Hubble Program (CCHP) A Multi-Wavelength Search for the Effects of Metallicity on the Cepheid Distance Scale. Part II: Theoretical Models and Synthetic Spectra
This is the second of two papers exploring the effects of metallicity on the multi-wavelength properties of Cepheids in terms of their multi-wavelength period-luminosity (PL) relations, impacting their use as extragalactic distance indicators, underpinning one of the most popular paths to estimating of the expansion rate of the Universe, Ho. In Paper I (Madore & Freedman 2024) we presented five tests for the influence of metallicity on galactic and extragalactic Cepheid PL relations, spanning n…

Probing Cosmic Curvature with Fast Radio Bursts and DESI DR2
J\'eferson A. S. Fortunato, Wiliam S. Hip\'olito-Ricaldi, Gustavo E. Romero
https://arxiv.org/abs/2506.01504

Probing Cosmic Curvature with Fast Radio Bursts and DESI DR2
The spatial curvature of the Universe remains a central question in modern cosmology. In this work, we explore the potential of localized Fast Radio Bursts (FRBs) as a novel tool to constrain the cosmic curvature parameter $Ω_k$ in a cosmological model-independent way. Using a sample of 80 FRBs with known redshifts and dispersion measures, we reconstruct the Hubble parameter $H(z)$ via artificial neural networks, which is then used to obtain angular diameter distances $D_A(z)$ through two comp…

Discovery of the Hybrid Response of Photoionized Gases
Zhicheng He, Tinggui Wang, Gary J. Ferland
https://arxiv.org/abs/2505.24242 https://

Discovery of the Hybrid Response of Photoionized Gases
Photoionized gases are prevalent throughout the universe. In such gases, the ion concentration typically exhibits two response modes to radiation: a positive response in the low-ionization state and a negative response in the high-ionization state. Here, we report the discovery of a widespread misalignment at the boundary between the above two response modes, and identify a third mode-the hybrid response-through time-dependent photoionization simulations. This phenomenon arises from the asynchr…

This https://arxiv.org/abs/2406.06635 has been replaced.
initial toot: https://mastoxiv.page/@arX…

The Hybrid Euclidean-Lorentzian Universe: Stability Considerations and the Point of Transition
TThe limited velocity implied by Lorentzian signature, prevents the universe to reach thermodynamic equilibrium implied by the CMB. Rapid expansion can occur by following Hawking and assuming a primordial Euclidean metric, in which case velocity is not limited and thermalization and rapid expansion are derived without the need to assume an ad-hoc field. Moreover, a mathematical model was given regarding the development of current Lorentzian space-time from the early Euclidean space-time in whic…

This https://arxiv.org/abs/1909.01734 has been replaced.
link: https://scholar.google.com/scholar?q=a

Comment on "Emergent Gravity and the Dark Universe" by Erik Verlinde
In "Emergent Gravity and the Dark Universe", Verlinde justifies a formula by three different derivations. However, we discovered that all these three derivations miss the same factor "2/3". If this factor is taken into account, Milgrom's constant used in Verlinde's emergent gravity must be given by $cH_0/9=0.76\times 10^{-10}$m/s$^2$ instead of Verlinde's original value $cH_0/6=1.1\times 10^{-10}$m/s$^2$, which roughly agrees with $1.2\times 10^{-10}$ m/s$^2$, Milgrom's constant used in Modifie…

This https://arxiv.org/abs/2504.06335 has been replaced.
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The most metal poor stars
The most metal-poor stars found in the Galaxy and in nearby galaxies are witnesses of the early evolution of the Universe. In a general picture in which we expect the metallicity to increase monotonically with time, as a result of the metal production in stars, we also expect the most metal-poor stars to be the most primitive objects accessible to our observations. The abundance ratios in these stars provide us important information on the first generations of stars that synthesised the nuclei …

This https://arxiv.org/abs/2403.02771 has been replaced.
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Absence of antisymmetric tensor fields : Clue from Starobinsky model of f(R) gravity
One of the surprising aspects of the present Universe, is the absence of any noticeable observable effects of higher-rank antisymmetric tensor fields in any natural phenomena. Here, we address the possible explanation of the absence of the higher rank antisymmetric tensor fields within the framework of $f(R)$ gravity. We explore the cosmological evolution of the scalar degrees of freedom associated with higher curvature term in a general $f(R)$ gravity model $f (R) = R +α_n R^n$. We show that …

This https://arxiv.org/abs/2502.04434 has been replaced.
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Searching for Inflationary Physics with the CMB Trispectrum: 1. Primordial Theory & Optimal Estimators
The primordial four-point function encodes a wealth of information about the inflationary Universe. Despite extensive theoretical work, most models of four-point physics have never been compared to data. In this series, we conduct a detailed analysis of Cosmic Microwave Background temperature and polarization trispectra, searching for a wide variety of phenomena including local effects, self-interactions, curvatons, DBI inflation, gauge fields, solid inflation, scalar field exchange, spinning m…