Alternative Models of Cosmology

Hi everyone,
I'm writing to you today to share my scientific speculation, which I've published on my website: 4-Sphere Cosmology

Speculative Framework and Cosmological Context

This theoretical exploration focuses on Galactic Recession, though the cosmological nature of the model necessitates engagement with broader themes such as dark matter dynamics, Cosmic Microwave Background (CMB) anisotropies, and related phenomena. These interdisciplinary connections were introduced to rigorously test whether the proposed framework, under its foundational hypotheses, would lead to physically or observationally inconsistent scenarios.
To address these challenges, the model incorporates necessary assumptions that remain purely conjectural (see for example the page: The 4-Sphere Metric Tensor. Nevertheless, the cornerstone of this speculation lies in its alignment with Hubble’s Law and the empirical validation of stellar distance measurements. These elements serve as critical anchors to ensure consistency with established observational constraints.

Invitation for Feedback

I would love to hear your thoughts. Instead of reading the full essay, I recommend checking out the short pages on the site, which provide a concise summary of the key ideas.
However, the critical point remains in (see the essay):

1. What is written about the Apparent magnitude in Appendix 1
2. What about the Time dilation in Appendix 2
3. What about the resulting supernova distance in Appendix 3

If errors are present in these areas, this theory is falsified.

Error reports, constructive criticism, and scholarly dialogue are warmly encouraged.

request for help from astronomers

Here to validate my findings, I compare luminosity distances calculated from redshift (z) and distance modulus (μ). For my analysis, I believe it is critical to retain the approach outlined in Astrophysical Journal Letters v.413, p.L105 - The Absolute Magnitudes of Type IA Supernovae . This method is not only accessible due to its reliance on widely available computational tools but, more importantly, it avoids the need for K-corrections during the initial sample selection phase. This ensures that results remain independent of any assumed cosmological model.
To conduct further validations, I need to explore the data from JWST, particularly its redshifted filters. For example, for a supernova at z = 1.0, the B-band (≈450 nm) would be redshifted to 900 nm, meaning I should use the F090W filter. The challenge now is finding the necessary observational data that describe the explosion and decay phases of some supernova, ideally including comparison stars. The V-band should also be useful for this analysis.
Searching on MAST Mikulski Archive for Space Telescopes becomes extremely challenging when formulating a generic query without knowing the target name (I struggled to identify a suitable supernova for my purposes).
So, I’d like to ask astronomers: Have JWST observations been conducted to capture the decay curves of Type Ia supernovae, specifically starting no later than maximum brightness and extending for at least 20 days post-maximum?

Key questions:

1. Is this method for deriving absolute magnitudes still valid, or is it considered outdated?
2. Can such data (light curves meeting the criteria above) be found in publicly accessible databases like MAST or others? How can I find them?

Dear forum members,
Following my previous thread error, I'm returning with a new proposal: a synthesis of various sources (based on a hypersphere-type model) designed for a clear and effective presentation.

It is encouraging to see how much interest the topic "hypersphere" is generating. Let's remember that, although Einstein proposed a static model in 1917, the idea of a spatially closed, finite, and boundless universe is historically linked to his work.
This idea, with such illustrious origins, has been revisited by many since. However, I think it's important to emphasize that all the models I've seen differ substantially from one another. Therefore, rather than focusing on the idea that unites them, I believe it's crucial to examine the descriptions that distinguish them.

In this spirit, I would like to present a model concerning Galactic Recession that I have developed. Its complexity and the references to arXiv publications (which I cannot summarize here) do not allow for a detailed description in this space.
The introduction of my research was uploaded on viXra as PDF. The latest version of the document

A new perspective on Hubble's law through a four-dimensional spatial model: 4-Sphere-Cosmology

is always freely available to everyone, after you click the link: [viXra:2504.0144], on the viXra page (Download are free and require no registration; at the time of writing, all other cited documents, most of them from arXiv, are also freely accessible).

That's the thing:
The recent observational capabilities of the James Webb Space Telescope (JWST) are opening new windows into the early universe, revealing distant galaxies whose apparent rapid formation poses significant questions to the standard ΛCDM cosmological model. Observations of galaxies at redshifts above 14 (see JADES-GS-z14-0), implying extremely old ages according to current FLRW metric-based distance assumptions, might stimulate a thorough reflection on fundamental cosmological principles. Will it be possible to explain all this without violating Hubble's law? But really, does violating the FLRW metric necessarily imply a violation of Hubble's law?

The Big Bang theory remains a robust and widely accepted paradigm. Nevertheless, any of its potential modifications could have profound implications for related fields, including Quantum Field Theory. This raises a fundamental question: is there a basic aspect that needs a conceptual revision? Although ΛCDM has achieved remarkable successes, many of its validations implicitly assume the FLRW metric. Could this dependence potentially introduce circular reasoning into model verification?

In this work, an alternative approach to the phenomenon of Galactic Redshift is proposed, offering a possible pathway for a careful modification of the ΛCDM model through the adoption of a non-FLRW metric. In this scenario, the Universe resides on the surface of a hypersphere expanding at a constant rate, with a radius growing as r = ct and with the Big Bang located at its center. This would explain why our physics manifests as if we were in a boundless system, despite the Universe having a finite volume: it suggests that, in the absence of Relativity, we would likely have been led to study an infinite and static universe.

While other models propose a hypersphere expanding with r = ct, an analysis of their main features reveals fundamental differences. The novelty of the model presented here lies in its definition of the Hubble constant: its geometry suggests a linear relationship between galactic recession and the arc angle (not the arc length). This perspective does not contest the validity of Hubble’s law, but introduces different predictions about the past and the future, which cannot be determined solely from current observations.

The use of the angle instead of the arc length produces significant implications, opening the possibility of applying Special Relativity to galactic recession. The redshift, which asymptotically approaches a time horizon of roughly 5 billion years after the Big Bang, implicitly explains why, at the boundaries of the observable Universe with JWST, we should not expect to see only "baby galaxies".

Specifically, the 4-Sphere framework, often considered part of alternative cosmologies, could potentially be reconciled with the Standard Model. Based on supernova distance measurements, I suggest that the dismissal of a Doppler-type redshift interpretation for Galactic Recession might warrant further and careful reconsideration.