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Cosmological foundations revisited with Pantheon+

ABSTRACT. We reanalyse the Pantheon+ supernova catalogue to compare a cosmology with non-FLRW evolution, the timescape cosmology, with the standard Lambda cold dark matter (⁠|Lambda$|CDM) cosmology. To this end, we analyse the Pantheon+ for a geometric comparison between the two models. We construct a covariance matrix to be as independent of cosmology as possible, including independence from the FLRW geometry and peculiar velocity with respect to FLRW average evolution. This framework goes far beyond most other definitions of model independence. We introduce new statistics to refine Type Ia supernova (SNe Ia) light-curve analysis. In addition to conventional galaxy correlation functions used to define the scale of statistical homogeneity we introduce empirical statistics that enables refined analysis of the distribution biases of SNe Ia light-curve parameters |beta c$| and |alpha x_1$|⁠. For lower redshifts, the Bayesian analysis highlights important features attributable to the increased number of low-redshift supernovae, the artefacts of model-dependent light-curve fitting, and the cosmic structure through which we observe supernovae. This indicates the need for cosmology-independent data reduction to conduct a stronger investigation of the emergence of statistical homogeneity and to compare alternative cosmologies in light of recent challenges to the standard model. Dark energy is generally invoked as a place-holder for new physics. For the first time, we find evidence that the timescape cosmology may provide a better overall fit than |Lambda$|CDM and that its phenomenology may help disentangle other astrophysical puzzles. Our from-first-principles reanalysis of Pantheon|$+$| supports future deeper studies between the interplay of matter and non-linear spacetime geometry in a data-driven setting.

Scientists detect mysterious suppression in cosmic structure growth

A new study in published in Physical Review Letters analyzes the most complete set of galaxy clustering data to test the ΛCDM model, revealing discrepancies in the formation of cosmic structures in the universe, hinting at a new physics.

The ΛCDM model is the standard model of cosmology describing the universe’s evolution, expansion, and structure. It encompasses (CDM), normal matter and radiation, and the cosmological constant (Λ), which accounts for .

The model has been successful in explaining several cosmological observations, including the large-scale structure of the universe, the accelerating expansion of the universe, and the (CMB) radiation, which is the afterglow of the Big Bang.

New method traces molecular gas mass in distant galaxies

Prof. Zhao Yinghe from the Yunnan Observatories of the Chinese Academy of Sciences, along with collaborators, have conducted a study examining the correlation between the [C II] 158 micron emission and the CO(1−0) line. Their findings were published in The Astrophysical Journal.

Molecular gas (H2) plays a critical role in , a key factor in the evolution of galaxies. Therefore, measuring the gas content in galaxies is crucial. However, the traditional tracer for H2 mass, the CO(1−0) line, is challenging to detect in the due to various factors, including lower metal content.

As a result, there is a pressing need for alternative H2 tracers, especially as more galaxies at high redshifts are being discovered.

The Machine at the End of Time — The Last Question Explained

The Last Question is a short story by Isaac Asimov which details the evolution of humanity and our journey to answering the one question that will determine the fate of the universe.

Thumbnail art: https://www.artstation.com/artwork/vgwvY

Assets:
Entropy: https://fs.blog/2018/11/entropy/ Inte… ship by Igor Sobolevsky: https://www.artstation.com/artwork/r1… Vessel by Paul Chadeisson: https://www.artstation.com/artwork/mQ… artist: / is_somebody_able_to_remove_the_little_atomic.

Music: uncharted worlds — mass effect: • mass effect — uncharted worlds extend…

🔵 ASSETS 🔵

Intro/Outro Music: Home — Resonance.

Posthumanism and Transhumanism in 2024🧠 #Posthumanism #Transhumanism #FutureTech

Exploring posthumanism and transhumanism: the future of human evolution.

Discover the fascinating realms of posthumanism and transhumanism! 🧠✨ How will future technologies redefine humanity? Join us as we explore the ethical implications, potential benefits, and groundbreaking advancements that could lead to a world where humans transcend their biological limitations. Will we embrace a future where mind and machine merge? Find out in this enlightening journey into the future of human evolution! 🌟

#Posthumanism #Transhumanism #FutureTech

New evidence of Organic Material identified on Ceres, the Inner Solar System’s most Water-rich Object after Earth

Six years ago, NASA’s Dawn mission communicated with Earth for the last time, ending its exploration of Ceres and Vesta, the two largest bodies in the asteroid belt. Since then, Ceres —a water-rich dwarf planet showing signs of geological activity— has been at the center of intense debates about its origin and evolution.

Now, a study led by IAA-CSIC, using Dawn data and an innovative methodology, has identified 11 new regions suggesting the existence of an internal reservoir of organic materials in the dwarf planet. The results, published in The Planetary Science Journal, provide critical insights into the potential nature of this celestial body.

In 2017, the Dawn spacecraft detected organic compounds near the Ernutet crater in Ceres’ northern hemisphere, sparking discussions about their origin. One leading hypothesis proposed an exogenous origin, suggesting these materials were delivered by recent impacts of organic-rich comets or asteroids.

Why Evolution Erased Dad’s Mitochondria

As we countdown the days until the New Year, we are revisiting our top stories of 2024! For today, a study may have uncovered why we get our energy from our mothers.

Read our coverage.


But what happens when this process fails?

Delaying PME results in impaired physiological function

Xue and the team studied PME in Caenorhabditis elegans (C. elegans), a translucent roundworm, to gain insight into this elusive mechanism. C. elegans only have 1,000 cells, yet they still develop a nervous system, gut, muscles and other tissues like humans.

Study sheds more light on the nature of compact symmetric object DA 362

Indian astronomers have performed a multiwavelength study of a gamma-ray emitting compact symmetric object known as DA 362. Results of the study, presented in a research paper published December 17 on the pre-print server arXiv, yield more insights into the nature of this enigmatic object.

Compact symmetric objects (CSOs) are young jetted (AGN) with an overall projected size below 3,300 light years. Although CSOs are still not well investigated, found that they showcase symmetric radio morphologies and are likely to be in the early stages of their evolution with kinematic ages smaller than a few thousand years. To date, only four CSOs have been found to emit gamma-rays.

The newest emitting CSO is DA 362, also known as B2 1413+34. It was initially classified as a blazar candidate of uncertain type, associated with a gamma-ray source designated 4FGL J1416.0+3443.