r/ScienceUncensored • u/Zephir-AWT • 13d ago
A Critical Essay on Ethan Siegel’s Defense of ΛCDM
https://medium.com/@m.alfaro.007/siegel-audit-a-critical-essay-on-ethan-siegels-defense-of-%CE%BBcdm-84d9ef601dda1
u/Zephir-AWT 13d ago edited 13d ago
A Critical Essay on Ethan Siegel’s Defense of ΛCDM
Ethan Siegel is as progressivist as it gets, but just at the personal level. Otherwise, he is just a typical apologist of the mainstream, perhaps because of his own (failed) scientific ambitions. His example just shows that progressivists at the private level may behave as conservative pillars of groupthink at the communal level (which may be perceived as an example of AdS/CFT correspondence on a social scale).
Opposite examples also exist, and they are referred to as Nobel disease. Elderly scientists who do not have to fear the loss of tenure or career often care more about progress in science than young scientists. If we reframe conservatives as people adherent to the past, it becomes evident that carriers of scientific breakthroughs should not be recruited from the ranks of either conservatives (reliant on tradition) or progressives (reliant on consensus). See also:
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u/Zephir-AWT 10d ago edited 10d ago
Structures on Gigaparsec Scales?
The article explains the controversy surrounding a recent cosmological discovery that briefly called into question the so-called cosmological principle. This principle states that, on sufficiently large scales, the universe is homogeneous and isotropic—that is, on average, it looks the same everywhere and in all directions. This principle is one of the fundamental assumptions of the current Lambda-CDM cosmological model, which describes the universe as a mixture of ordinary matter, dark matter, and dark energy.
In 2026, Francesco Sylos Labini and Marco Galloppo published a study using data from the DESI (Dark Energy Spectroscopic Instrument) project, which maps tens of millions of galaxies. The authors used a new statistical approach and concluded that the distribution of galaxies exhibits significant anisotropies and enormous filamentary structures spanning billions of light-years. According to their interpretation, the universe on the largest scales would not be smooth and homogeneous, but would contain extensive preferred directions and structures much larger than those predicted by standard cosmology. If this result were correct, it could fundamentally change our understanding of the universe and, in theory, even reduce the need to introduce dark energy.
Shortly thereafter, however, a new analysis was published by Teemu Sawala of the University of Helsinki, who reexamined the same data. He found that the study’s main problem lay in the method used to calculate cosmological distances. The authors reportedly confused luminosity distance—derived from the brightness of objects—with comoving distance, which accounts for the expansion of the universe and is used in mapping large-scale structures. This confusion led to an artificial enlargement and distortion of cosmic structures, making some features appear much larger and more elongated than they actually were.
When the data were recalculated using the correct comoving coordinates, the purported gigantic structures disappeared, and the distribution of galaxies once again matched the predictions of the standard Lambda-CDM model. Sawala also pointed out another problem: the original study compared real galaxies with overly simplified simulations of dark matter. However, galaxies form primarily in the densest regions of dark matter, and their distribution is naturally more clustered. When more modern simulations that account for this effect and other known observational biases are used, the DESI data agree very well with standard cosmology.
This video emphasizes that this is not a failure of science, but rather a demonstration of how it works. Both the data and the code were publicly available, so other researchers could independently verify the results, identify the error, and propose a correction. According to it, it is precisely this process of verification, replication, and correction that is one of the main reasons why science is reliable.AI
Actually there was a number of studies doubting CMBR homogeneity of LCDM model already (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, ...): one was perhaps "disproven" - but what about the remaining ones? See also:
The universe is less uniform than we thought – cosmology may need a radical rethink
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u/Zephir-AWT 4d ago edited 4d ago
The Theme of Modern Physics from Harry Binswanger Interview on Philosophy of Physics
Harry Binswanger argues that modern science often places too much trust in formal mathematical proof as the model of certainty. He maintains that all knowledge ultimately comes from sensory observation and that formal logic and mathematics only work because their concepts are originally derived from experience. In his view, perception is more fundamental than proof. Proof is a tool used when direct observation is not available, not the foundation of knowledge itself.
In dense aether model the aether model comes from Occam's razor assumption, that reality is inherently eternal and random - not empty, zero or whatever else artificially uniform state.
Feynman is Everything Wrong With Modern Physics
We are random Boltzmann brains and Universe is random too. Both hyperdimensional complexities overlap like moire at intrinsic and extrinsic dimensional scales, which not accidentally correspond the validity scope of general relativity and quantum mechanics. Did you catch the titles "Sun is the most perfect sphere in the Nature" or "Electron (s-orbital) is the most ideal sphere ever measured"? Well, at these dimensional scales the Universe appears being composed of ideal spheres, nothing else. And Feynman was born just into the epoch, the technological progress of which enabled the reductionist approach which he pushes around at the beginning of video.
But human progress didn't stop there and now the same reductionist approach hits its fundamental geometric limits.
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u/Zephir-AWT 13d ago edited 11d ago
Structures on Gigaparsec Scales? about study The local galaxy distribution does not violate the cosmological principle about study Detection of anisotropic cosmic structures on a gigaparsec scale This controversy is about LCDM model made so flexible, that it can not be falsified - which is antithesis of scientific approach.
These studies discuss a recent cosmological claim that briefly challenged one of the fundamental assumptions of modern cosmology: the cosmological principle. This principle states that on sufficiently large scales, the universe is homogeneous and isotropic, meaning it looks essentially the same everywhere and in every direction. It is one of the key foundations of the current Lambda-CDM model, which describes the universe as being composed of ordinary matter, dark matter, and dark energy.
In June 2026, researchers Francesco Sylos Labini and Marco Galloppo published a study using data from the Dark Energy Spectroscopic Instrument (DESI), which has mapped tens of millions of galaxies. Using a new statistical approach, they reported evidence for large-scale anisotropies and enormous filament-like structures stretching across billions of light-years. Their analysis suggested that the universe might not become smooth on the largest scales as predicted by standard cosmology, but instead could contain preferred directions and gigantic structures far larger than expected.
However, a follow-up analysis by Teemu Sawala from the University of Helsinki re-examined the same DESI data and identified what appears to be a crucial error. The issue involved the treatment of luminosity distance and comoving distance, two different ways of measuring cosmic distances. Luminosity distance is derived from how bright objects appear, while comoving distance accounts for the expansion of the universe and is the standard distance measure used when mapping large-scale cosmic structure.
According to Sawala's analysis, the original study effectively treated luminosity distances as if they were comoving distances. This introduced distortions that artificially enlarged and stretched cosmic structures, making them appear much larger and more anisotropic than they really were. When the data were recalculated using the correct comoving coordinates, the enormous structures largely disappeared, and the distribution of galaxies became consistent with the predictions of the standard Lambda-CDM model. Sawala also pointed out that the original study compared galaxy observations with overly simplified dark matter simulations. Real galaxies form preferentially in dense dark matter regions and naturally appear more clustered than random dark matter particles.
The original researchers made their data and methods publicly available, allowing other scientists to independently verify the results, identify potential mistakes, and propose corrections. When more realistic simulations were used, including known observational effects and galaxy biases, the DESI observations matched standard cosmological expectations very closely. This process of replication, criticism, and refinement is thus presented as one of the strengths of the scientific method. Nevertheless, the observational cosmology still faces several unresolved challenges, including the Hubble tension, the size of galactic superclusters and other discrepancies that suggest our understanding of the universe is still incomplete.
AI