The great Russian physicist and Nobel Prize winner Lev Landau once commented that “cosmologists are often in error, but ever in doubt”. In studying the history of the universe, there is always a chance that we have found all this wrong, but we never let this stand go in the way of our inquiry.
A few days ago, a new press release announced a groundbreaking findings from the Dark Energy Spectroscopy Instrument (DESI), which is installed on the Meal Telescope in Arizona. This huge survey, which has a position of 15 million galaxies, forms the largest three -dimensional mapping of the universe to date. For reference, light from the distant galaxies recorded in the desi catalog was emitted 11 billion years ago, when the universe was the fifth of its current age.
Desi researchers studied a characteristic in the distribution of galaxies called astronomers called “Barian Acceptive oscillations”. By comparing the very early universe and observations of supernova, they are able to suggest that dark energy – the mysterious forces promoting the expansion of our universe – is not stable in the history of the universe.
An optimistic on the situation is that the nature of dark matter and dark energy will be discovered sooner or later. The first glimpse of desi results provides a small slever of hope to achieve it at least.
However, this cannot happen. We can search and make no headway to understand the situation. If this happens, we will need to reconsider not only our research, but also the study of cosmology. We will need to find a completely new cosmeological model, a one that works with our current, but also explains this discrepancy. Needless to say, this will be a long order.
For many people who are interested in science, this is an exciting, potential revolutionary possibility. However, this kind of renovation of cosmology, and not really all of science, is not new, as is argued in the 2023 book The Relations of Science.
Search for two numbers
Back in 1970, Alan Sandage, pointing to two numbers, wrote a very quoted paper that brings us closer to the north about the nature of cosmic expansion. Their goal was to measure them and find out how they change over the cosmic time. Those numbers are Hubble constants, H, and recession parameters, q₀.
The first of these two numbers tells us how fast the universe is expanding. The second is the signature of gravity: as an attractive force, gravity should be drawn against cosmic expansion. Some figures have shown deviation from the Hubble-Loma law, of which the second number of sandage, Q₀, is a solution.
No significant deviation from the straight line of Hubble could be found until in 1997, the supernova cosmology project of Saul Parliament and the high-Z SN search team led by Adam Rece and Brian Schmids were not successful. The goal of these projects was to discover and follow the supernova explosion in a very distant galaxies.
These projects found a clear deviation from the simple straight line of the Hubble-Limtre law, but with a significant difference: the expansion of the universe is increasing rapidly, not declaring. Peremators, Resses and Schmidy attributed this deviation to Einstein’s cosmological constant, depicted by the Greek letter Lambda, λ, and it belongs to the recession parameters.
His work gave him the 2011 Nobel Prize in Physics.
Dark Energy: 70% of the universe
Surprisingly, this lambda-matter, also known as dark energy, is a major component of the universe. It is extending the expansion of the universe to the point where the force of gravity is overred, and it is about 70% of the total density of the universe.
We do not know very little or anything about cosmological constant, λ. In fact, we do not even know that it is a stable. Einstein first stated that there was a continuous energy field when he had created his first cosmological model obtained from general relativity in 1917, but his solution was neither expanding nor contracting. It was stable and irreversible, and so the area had to be stable.
The creation of a more sophisticated model incorporating this continuous region was an easy task: they were obtained by a friend of Belgian physicist Lematre, Einstein. The standard cosmic science model is today based on the work of the lametra, and is referred to as a λ cold dark matter (λCDM) model.
Desi measurements on their own are completely corresponding to this model. However, by combining them with the comments of cosmic microwave backgrounds and supernova, the best fitting model incorporates a dark energy that developed at cosmic time, and it (potentially) will no longer dominate the future. In short, this would mean that the cosmological constant does not explain dark energy.
Big crunch
In 1988, the 2019 Physics Nobel Prize winner Pje Peels wrote a paper with Bharat Ratra on the possibility that there is a cosmological constant that varies over time. When he published this paper, there was no serious body of opinion about λ.
This is an attractive suggestion. In this case the current phase of quick expansion will be transient and will end at some point in the future. Other stages of cosmic history have a beginning and an end: inflation, radiation-enhance era, the era of case-content, and so on.
Therefore, the current dominance of dark energy may decline at the cosmic time, which means it will not be a universe related constant. The new paradigm will mean that the current expansion of the universe may eventually be reversed in the “large crunch”.
Other cosmologists are more alert, at least not Carl Sagan, who wisely stated that “extraordinary claims require extraordinary evidence”. It is important to have many, independent lines of evidence pointing to the same conclusion. We are not there yet.
Answer can come from one of today’s ongoing projects-only desi but euclid and J-PAS-whose purpose is to find out the nature of dark energy through mass galaxies.
While the functioning of the universe itself is for debate, one thing is sure – an attractive time for cosmology is on the horizon.
,Author: Bernard Jetie Jones, Emeritus Professor, University of Grontan; Lisia Varde, Professor Icearia de Cosmologia NL Ikqb de La Universidad de Barcelona, Universitate de Barcelona; Visent J. Martinez, Catedrático de Astronomía Y Astrofísica de la universitat de València, y Miembro del Autronómico de la Misma Instatución, Universitat De València, and Virginia l Trimble, Physt Physics and astronyry, irvine, irvine, irvine, irvine, californian, irvine, californian, irvine, anversity of california, irvine, irvini
,Disclosure statement: Licia Verde AEI (Spanish State Research Agency) receives funds from Project No. PID2022–141125NB-I00, and has earlier received funds from the European Research Council. Lisia Varde is a member of the Desi Cooperation Team. Visent J. Martinez receives funding from the European Union Nextganes and Generalitat Valensiana in 2022, which 2022 calls “Program Day Plane Complementaryoos Day I+D+I”, Project (Val-JPA), Reference ASFAE/2022/025, The Research Project Pid2023-149420n-IIS ERDF/EU, and The Project of Excellence Promato Ciprom/2023/11 Consialia de Edukesione, Universidads Y Employment (Generalitte Valensiana). He is a member of the Spanish Astronomy Society, Spanish Royal Physics Society and Royal Spanish Mathematical Society Bernard Jets Jones and Virginia L Trimbal do not work for funding from any company or organization, consult, or will benefit from this article, and will benefit from this article, and their educational appointment will be benefited, and their educational appointment will benefit from this article. Not disclosed)
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