Question BIG BANG EVIDENCE

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I'm sharing these papers so that you can form your own opinion.
Expressing my opinion.
Re-cycling bangs seems the way to go.
This can be proven.
Rather than trying to explain how trillions of Galaxies formed within 13.8 billion years.

[Submitted on 29 Aug 2024]

A new approach in classical Klein-Gordon cosmology: "Small Bangs", inflation and Dark Energy​

Eleni-Alexandra Kontou, Nicolai Rothe
In this work, we analyze the cosmological model in which the expansion is driven by a classical, free Klein-Gordon field on a flat, four-dimensional Friedmann-Lemaître-Robertson-Walker spacetime. The model allows for arbitrary mass, non-zero cosmological constant and coupling to curvature. We find that there are strong restrictions to the parameter space, due to the requirement for the reality of the field values. At early cosmological times, we observe Big Bang singularities, solutions where the scale factor asymptotically approaches zero, and Small Bangs. The latter are solutions for which the Hubble parameter diverges at a finite value of the scale factor. They appear generically in our model for certain curvature couplings. An early inflationary era is observed for a specific value of the curvature coupling without further assumptions (unlike in many other inflationary models). A late-time Dark Energy period is present for all solutions with positive cosmological constant, numerically suggesting that a "cosmic no-hair" theorem holds under more general assumptions than the original Wald version which relies on classical energy conditions. The classical fields in consideration can be viewed as resembling one-point functions of a semiclassical model, in which the cosmological expansion is driven by a quantum field.
 
The more we have research the more we learn.
What was before and how things happen after is part of the understanding.

[Submitted on 3 Sep 2024]

Investigating early and late-time epochs in f(Q) gravity​

Ameya Kolhatkar, Sai Swagat Mishra, P.K. Sahoo
In the following work, a new hybrid model of the form f(Q)=Q(1+a)+bQ20Q has been proposed and confronted using both early as well as late-time constraints. We first use conditions from the era of Big Bang Nucleosynthesis (BBN) in order to constrain the models which are further used to study the evolution of the Universe through the deceleration parameter. This methodology is employed for the hybrid model as well as a simple model of the form α1Q+α2Q0 which is found to reduce to ΛCDM. The error bar plot for the Cosmic Chronometer (CC) and Pantheon+SH0ES datasets which includes the comparison with ΛCDM, has been studied for the constrained hybrid model. Additionally, we perform a Monte Carlo Markov Chain (MCMC) sampling of the model against three datasets -- CC, Pantheon+SH0ES, and Baryon Acoustic Oscillations (BAO) to find the best-fit ranges of the free parameters. It is found that the constraint range of the model parameter (a) from the BBN study has a region of overlap with the ranges obtained from the MCMC analysis. Finally, we perform a statistical comparison between our model and the ΛCDM model using AIC and BIC method.
 
You try to fit the model when you assume that the BBT is correct.

[Submitted on 3 Sep 2024]

Cosmology using numerical relativity​

Josu C. Aurrekoetxea, Katy Clough, Eugene A. Lim
This review is an up-to-date account of the use of numerical relativity to study dynamical, strong-gravity environments in a cosmological context. First, we provide a gentle introduction into the use of numerical relativity in solving cosmological spacetimes, aimed at both cosmologists and numerical relativists. Second, we survey the present body of work, focusing on general relativistic simulations without approximations, organised according to the cosmological history -- from cosmogenesis, through the early hot Big Bang, to the late-time evolution of universe. In both cases, we discuss the present state-of-the-art, and suggest directions in which future work can be fruitfully pursued.
 
Read this and make up your own mind.

[Submitted on 22 Aug 2024]

Observable Signatures of No-Scale Supergravity in NANOGrav​

Spyros Basilakos, Dimitri V. Nanopoulos, Theodoros Papanikolaou, Emmanuel N. Saridakis, Charalampos Tzerefos
In light of NANOGrav data we provide for the first time possible observational signatures of Superstring theory. Firstly, we work with inflection-point inflationary potentials naturally realised within Wess-Zumino type no-scale Supergravity, which give rise to the formation of microscopic primordial black holes (PBHs) triggering an early matter-dominated era (eMD) and evaporating before Big Bang Nucleosythesis (BBN). Remarkably, we obtain an abundant production of primordial gravitational waves (PGW) at the frequency ranges of nHz, Hz and kHz and in strong agreement with Pulsar Time Array (PTA) GW data. This PGW background could serve as a compelling observational signature for the presence of quantum gravity via no-scale Supergravity.
 
Is this evidence assumed evidence or is it just an opinion?

[Submitted on 5 Sep 2024]

RUBIES Reveals a Massive Quiescent Galaxy at z=7.3​

Andrea Weibel, Anna de Graaff, David J. Setton, Tim B. Miller, Pascal A. Oesch, Gabriel Brammer, Claudia D.P. Lagos, Katherine E. Whitaker, Christina C. Williams, Josephine F.W. Baggen, Rachel Bezanson, Leindert A. Boogaard, Nikko J. Cleri, Jenny E. Greene, Michaela Hirschmann, Raphael E. Hviding, Adarsh Kuruvanthodi, Ivo Labbé, Joel Leja, Michael V. Maseda, Jorryt Matthee, Ian McConachie, Rohan P. Naidu, Guido Roberts-Borsani, Daniel Schaerer, Katherine A. Suess, Francesco Valentino, Pieter van Dokkum, Bingjie Wang
We report the spectroscopic discovery of a massive quiescent galaxy at zspec=7.29±0.01, just ∼700Myr after the Big Bang. RUBIES-UDS-QG-z7 was selected from public JWST/NIRCam and MIRI imaging from the PRIMER survey and observed with JWST/NIRSpec as part of RUBIES. The NIRSpec/PRISM spectrum reveals one of the strongest Balmer breaks observed thus far at z>6, no emission lines, but tentative Balmer and Ca absorption features, as well as a Lyman break. Simultaneous modeling of the NIRSpec/PRISM spectrum and NIRCam and MIRI photometry (spanning 0.9−18μm) shows that the galaxy formed a stellar mass of log(M∗/M⊙)=10.23+0.04−0.04 in a rapid ∼100−200Myr burst of star formation at z∼8−9, and ceased forming stars by z∼8 resulting in logsSFR/yr−1<−10. We measure a small physical size of 209+33−24pc, which implies a high stellar mass surface density within the effective radius of log(Σ∗,e/M⊙kpc−2)=10.85+0.11−0.12 comparable to the densities measured in quiescent galaxies at z∼2−5. The 3D stellar mass density profile of RUBIES-UDS-QG-z7 is remarkably similar to the central densities of local massive ellipticals, suggesting that at least some of their cores may have already been in place at z>7. The discovery of RUBIES-UDS-QG-z7 has strong implications for galaxy formation models: the estimated number density of quiescent galaxies at z∼7 is >100× larger than predicted from any model to date, indicating that quiescent galaxies have formed earlier than previously expected.
 

Nucleosynthesis is the process of quantum matter ejected from the center of compact cores and reforming atoms and complex matter. The BBT scientists have labeled it as the Big Bang Nucleosynthesis without evidence unless I'm missing something.​

Big Bang Nucleosynthesis​

Ryan Cooke (Centre for Extragalactic Astronomy, Durham University)
One of the most compelling pieces of evidence of the Hot Big Bang model is the realisation and confirmation that some nuclides were created shortly after the Big Bang. This process is referred to as Big Bang nucleosynthesis (or, sometimes, primordial nucleosynthesis), and is the end-product of putting neutrons and protons in a hot, expanding Universe. Big Bang nucleosynthesis currently provides our earliest test of cosmology, and it is the only experiment currently designed that is simultaneously sensitive to all four known fundamental forces: the gravitational force, the electromagnetic force, the strong force and the weak force. Our theoretical understanding of Big Bang nucleosynthesis and the measurement of the primordial abundances together represents one of the strongest pillars of the standard cosmological model. In this chapter, we will develop an intuitive understanding of Big Bang nucleosynthesis, discuss modern calculations of this process, and provide a summary of the current state-of-the-art measurements that have been made. Overall, Big Bang nucleosynthesis is in remarkable agreement with various cosmological probes, and it is this agreement that serves to strengthen our confidence in the general picture of cosmology that we have today.
 
Non-stop research to prove the BBT.
Trying to fit the images to BBT is quite difficult.

[Submitted on 23 Sep 2024]

Big Bang Nucleosynthesis constraints on resonant DM annihilations​

Pieter Braat, Marco Hufnagel
We perform a systematic study of BBN constraints from photodisintegration for scenarios in which dark-matter annihilations are resonantly-enhanced. To this end, we implement and make available a new class ResonanceModel within an updated version v1.3.0 of ACROPOLIS. While the corresponding implementation is done in a rather model-independent way, we also make available three benchmark models that can be used to calculate constraints for more concrete scenarios. Using this new version of ACROPOLIS, we present for the first time the corresponding constraints on resonantly-enhanced s-wave and p-wave annihilations. We show that for s-wave annihilations the bounds are usually very similar to the ones without a resonance, while for p-wave annihilations the bounds can be significantly stronger.
 
I'm afraid I have to disagree with this paper. could be wrong.
Regardless, It's worth reading.


[Submitted on 25 Sep 2024]

Extended hot dust emission around the earliest massive quiescent galaxy​

Zhiyuan Ji, Christina C. Williams, George H. Rieke, Jianwei Lyu, Stacey Alberts, Fengwu Sun, Jakob M. Helton, Marcia Rieke, Irene Shivaei, Francesco D'Eugenio, Sandro Tacchella, Brant Robertson, Yongda Zhu, Roberto Maiolino, Andrew J. Bunker, Yang Sun, Christopher N. A. Willmer
A major unsolved problem in galaxy evolution is the early appearance of massive quiescent galaxies that no longer actively form stars only ∼1 billion years after the Big Bang. Their high stellar masses and extremely compact structure indicate that they formed through rapid bursts of star formation between redshift z∼6−11. Theoretical models of galaxy evolution cannot explain their high number density, rapid growth and truncation of star formation at such early times, which likely requires extreme feedback to destroy the cold interstellar medium (the fuel for star formation). We report the discovery of a significant reservoir of hot dust in one of the most distant known examples at z=4.658, GS-9209. The dust was identified using JWST's Mid-Infrared Instrument (MIRI), whose unprecedented sensitivity and high spatial resolution, for the first time, firmly show that this dust is significantly more extended than the stars by ≳3 times. We find that the dust has preferentially been evacuated or diluted in the galaxy center. Our analysis finds that the extended hot dust emission is consistent with recent heating by a younger and more spatially extended generation of star formation. This reveals that the earliest quiescent galaxies did not form in a single rapid burst; instead, similar to galaxy growth at later times, the center formed first with star formation continuing in an extended envelope. The growth of this galaxy is truncating from the inside out, consistent with central gas depletion from early AGN feedback.
 
Even though I'm afraid I have to disagree with this paper.
Interesting reading.
Hey! I could be wrong.


[Submitted on 30 Sep 2024]

Big Bang: a theory or fact​

D. N. Basu
The discovery and confirmation that some nuclides were formed soon after the Big Bang is one of the strongest arguments in favour of the Hot Big Bang theory. The process of combining protons and neutrons in a hot, expanding universe is known as Big Bang nucleosynthesis (or, occasionally, primordial nucleosynthesis). The only experiment that is currently constructed to be concurrently sensitive to all four known fundamental forces - gravitational, electromagnetic, strong and weak forces - is big bang nucleosynthesis, which offers our earliest test of cosmology. Combined, our theoretical comprehension of Big Bang nucleosynthesis and the measurement of primordial abundances constitute one of the most robust foundations for the conventional cosmological model. This deliberation provides modern calculations of Big Bang nucleosynthesis, help readers gain an intuitive knowledge of the process and give an overview of the most recent state-of-the-art measurements. Our trust in the current basic picture of cosmology is reinforced by the overall amazing agreement between Big Bang nucleosynthesis and many cosmological probes.
 
Evidence is sometimes not evidence, but! an opinion.
Read further and judge for yourself.

[Submitted on 9 Sep 2024]

Big Bang Nucleosynthesis​

Ryan Cooke (Centre for Extragalactic Astronomy, Durham University)
One of the most compelling pieces of evidence of the Hot Big Bang model is the realisation and confirmation that some nuclides were created shortly after the Big Bang. This process is referred to as Big Bang nucleosynthesis (or, sometimes, primordial nucleosynthesis), and is the end-product of putting neutrons and protons in a hot, expanding Universe. Big Bang nucleosynthesis currently provides our earliest test of cosmology, and it is the only experiment currently designed that is simultaneously sensitive to all four known fundamental forces: the gravitational force, the electromagnetic force, the strong force and the weak force. Our theoretical understanding of Big Bang nucleosynthesis and the measurement of the primordial abundances together represents one of the strongest pillars of the standard cosmological model. In this chapter, we will develop an intuitive understanding of Big Bang nucleosynthesis, discuss modern calculations of this process, and provide a summary of the current state-of-the-art measurements that have been made. Overall, Big Bang nucleosynthesis is in remarkable agreement with various cosmological probes, and it is this agreement that serves to strengthen our confidence in the general picture of cosmology that we have today.
 
Watching that video for 35 minutes to find out if it actually says anything is not my style. The presenter seems more interested in talking for as long as possible, rather than conveying his actual concept as clearly and concisely as possible. That is what happens when you get paid for length instead of efficiency.

I'll search for the same info in print - much faster. Googling "JADES-GS-z14-0" turns up this: https://en.wikipedia.org/wiki/JADES-GS-z14-0 .

Wikipedia says that it has a redshift of 14.32, which dates it to just 290 million years after the "Big Bang". It is only 1,600 light years wide, and extremely bright. And it has spectral lines of oxygen as well as hydrogen. That last part seems to indicate to me that massive stars have already been born, lived their lives up to at least fusing elements up to oxygen in their cores, and released those elements in supernovas.

If that video presenter has a different opinion, he has failed to communicate it to me. He needs to get to his point before people just leave.

The most interesting thing is that Webb has the capability to see even higher redshifts, so we are just getting started on this.
 
It's an ongoing path to find out the unknown.


[Submitted on 27 Nov 2024]

Modular invariant inflation, reheating and leptogenesis​

Gui-Jun Ding, Si-Yi Jiang, Yong Xu, Wenbin Zhao
We use modular symmetry as an organizing principle that attempts to simultaneously address the lepton flavor problem, inflation, post-inflationary reheating, and baryogenesis. We demonstrate this approach using the finite modular group A4 in the lepton sector. In our model, neutrino masses are generated via the Type-I see-saw mechanism, with modular symmetry dictating the form of the Yukawa couplings and right-handed neutrino masses. The modular field also drives inflation, providing an excellent fit to recent Cosmic Microwave Background (CMB) observations. The corresponding prediction for the tensor-to-scalar ratio is very small, r∼O(10−7), while the prediction for the running of the spectral index, α∼−O(10−3), could be tested in the near future. An appealing feature of the setup is that the inflaton-matter interactions required for reheating naturally arise from the expansion of relevant modular forms. Although the corresponding inflaton decay rates are suppressed by the Planck scale, the reheating temperature can still be high enough to ensure successful Big Bang nucleosynthesis. We find that the same couplings responsible for reheating also contribute to generating part of the baryon asymmetry of the Universe through non-thermal leptogenesis.
 
The Next few years will see the end, or the rethinking of the Big Bang .
The more we get to know the less probable the Big Bang started.

[Submitted on 2 Dec 2024]

Constraints on the Pre-Big Bang scenario from a cosmological interpretation of the NANOGrav data​

P. Conzinu, G. Fanizza, M. Gasperini, E. Pavone, L. Tedesco, G. Veneziano
We discuss a recently proposed interpretation of the signal detected by the North American Nanohertz Observatory for Gravitational Waves (NANOGrav) as due to a relic stochastic background of primordial gravitons, produced in the context of the string cosmology pre-big bang scenario. We show that such interpretation cannot be reconciled with a phenomenologically viable minimal version of such scenario, while it can be allowed if one considers an equally viable but generalised, non-minimal version of pre-big bang evolution. Maintaining the S-duality symmetry throughout the high-curvature string phase is possible although somewhat disfavoured. The implications of this non-minimal scenario for the power spectrum of curvature perturbations are also briefly discussed.
 
Keep reading and do your own research, what seems now may be different later.

[Submitted on 3 Dec 2024]

Massive black holes or stars first: the key is the residual cosmic electron fraction​

Muhammad A. Latif, Sadegh Khochfar
Recent James Webb Space Telescope observations have unveiled that the first supermassive black holes (SMBHs) were in place at z ≥ 10, a few hundred Myrs after the Big Bang. These discoveries are providing strong constraints on the seeding of BHs and the nature of the first objects in the Universe. Here, we study the impact of the freeze-out electron fractions (fe) at the end of the epoch of cosmic recombination on the formation of the first structures in the Universe. At fe below the current fiducial cosmic values of ∼10−4, the baryonic collapse is delayed due to the lack of molecular hydrogen cooling until the host halo masses are increased by one to two orders of magnitude compared to the standard case and reach the atomic cooling limit. This results in an enhanced enclosed gas mass by more than an order of magnitude and higher inflow rates of up to 0.1 M⊙/yr. Such conditions are conducive to the formation of massive seed BHs with ∼104 M⊙. Our results reveal a new pathway for the formation of massive BH seeds which may naturally arise from free
 

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