The cosmological constant, introduced a century ago by Albert Einstein in his theory of general relativity, is a thorn in the side of physicists.
The difference between the theoretical prediction of this parameter and its measurement based on astronomical observations is of the order of 10^121.
In an article to be published in Physics Letters B, a researcher from the University of Geneva (UNIGE), Switzerland, proposes an approach that may seemingly resolve this inconsistency. The original idea in the paper is to accept that another constant—Newton's universal gravitation G, which also forms part of the equations on general relativity—may vary.
This potentially major breakthrough, which has been positively received by the scientific community, still needs to be pursued in order to generate predictions that can be confirmed (or refuted) experimentally.
"My work consists of a new mathematical manipulation of the equations of general relativity that finally makes it possible to harmonize theory and observation on the cosmological constant," says Lucas Lombriser.
Professor Lombriser had the original idea a few years ago of introducing a variation into the universal constant of gravitation G (Newton's) which appears in Einstein's equations. This means that the universe in which we live (with a G of 6.674 08 × 10^-11 m3 / kg s^2) becomes a special case among an infinite number of different theoretical possibilities!
After numerous developments and hypotheses, professor Lombriser's mathematical approach means it is possible to calculate the parameter ΩΛ (omega lambda), which is another way of expressing the cosmological constant but which is much easier to manipulate.
This parameter designates also the current fraction of the universe that is made up of dark energy (the rest being composed of matter). The theoretical value obtained by the Geneva-based physicist is 0.704 or 70.4 percent. This figure is in close agreement with the best experimental estimate obtained to date, 0.685 or 68.5 percent, stating that this is a huge improvement over the 10^121 discrepancy.
The cosmological constant appears in Einstein's field equation in the form as shown in the Image below , where the Ricci tensor/scalar R and the metric tensor g describe the structure of spacetime, the stress—energy tensor T describes the energy and momentum density and flux of the matter in that point in spacetime, and the universal constants G and c are conversion factors that arise from using traditional units of measurement. When /\ is zero, this reduces to the field equation of general relativity usually used in the mid-20th century. When T is zero, the field equation describes empty space (the vacuum).
This initial success now needs to be followed by further analyses in order to verify whether the new framework proposed by Lombriser can be used to reinterpret or clarify other mysteries of cosmology. The physicist has already been invited to present and explain his approach in scientific conferences, which reflects the interest shown by the community.
The difference between the theoretical prediction of this parameter and its measurement based on astronomical observations is of the order of 10^121.
In an article to be published in Physics Letters B, a researcher from the University of Geneva (UNIGE), Switzerland, proposes an approach that may seemingly resolve this inconsistency. The original idea in the paper is to accept that another constant—Newton's universal gravitation G, which also forms part of the equations on general relativity—may vary.
This potentially major breakthrough, which has been positively received by the scientific community, still needs to be pursued in order to generate predictions that can be confirmed (or refuted) experimentally.
"My work consists of a new mathematical manipulation of the equations of general relativity that finally makes it possible to harmonize theory and observation on the cosmological constant," says Lucas Lombriser.
Professor Lombriser had the original idea a few years ago of introducing a variation into the universal constant of gravitation G (Newton's) which appears in Einstein's equations. This means that the universe in which we live (with a G of 6.674 08 × 10^-11 m3 / kg s^2) becomes a special case among an infinite number of different theoretical possibilities!
After numerous developments and hypotheses, professor Lombriser's mathematical approach means it is possible to calculate the parameter ΩΛ (omega lambda), which is another way of expressing the cosmological constant but which is much easier to manipulate.
This parameter designates also the current fraction of the universe that is made up of dark energy (the rest being composed of matter). The theoretical value obtained by the Geneva-based physicist is 0.704 or 70.4 percent. This figure is in close agreement with the best experimental estimate obtained to date, 0.685 or 68.5 percent, stating that this is a huge improvement over the 10^121 discrepancy.
The cosmological constant appears in Einstein's field equation in the form as shown in the Image below , where the Ricci tensor/scalar R and the metric tensor g describe the structure of spacetime, the stress—energy tensor T describes the energy and momentum density and flux of the matter in that point in spacetime, and the universal constants G and c are conversion factors that arise from using traditional units of measurement. When /\ is zero, this reduces to the field equation of general relativity usually used in the mid-20th century. When T is zero, the field equation describes empty space (the vacuum).
This initial success now needs to be followed by further analyses in order to verify whether the new framework proposed by Lombriser can be used to reinterpret or clarify other mysteries of cosmology. The physicist has already been invited to present and explain his approach in scientific conferences, which reflects the interest shown by the community.
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