Free Astronomy Magazine July-August 2025 ARABIC VERSION

T Potential inconsistencies in the standard cosmologicalmodel byNOIRLab JosieFenske5FernandoTorrecilla he Λ CDM(Lambda-CDM)modelhasbeenthe foundation of modern cosmology for some timenow,successfullydescribinglarge-scale structuresintheUniverse.Itproposesthat95%of thecosmosiscomposedofdarkmatter(25%)and darkenergy(70%)—mysterioussubstanceswhose natureremainsunknown.Only5%oftheUniverse consists of ordinary matter. Darkenergy,representedbythecosmologicalcon- stant( Λ ),isthoughttodrivetheacceleratingex- pansion of the Universe, maintaining a constant en- ergydensityovertime.However,newresultsfrom theDarkEnergySurvey(DES),presentedinapaper appearing on arXiv and in talks at the American Physical Society’s Global Physics Summit in Ana- heim, California, hint at a deviation from this as- sumption, suggesting that dark energy might evolveovertime.Thesefindingsalignwithprevi- ous studies, reinforcing their significance. TheDESisaninternationalcollaborationcompris- ing more than 400 scientists from over 25 institu- tions,ledbytheU.S.DepartmentofEnergy’sFermi NationalAcceleratorLaboratory.TheDESwascon- ductedusingthe570-megapixelDepartmentofEn- ﻌـﺪ ﻧﻤﻮذج ﻻﻣ ﺒﺪا ﻟﻠﻤـﺎدة ا ﻈﻠﻤـﺔ اﻟﺒـﺎردة أﺳـﺎ س ﻋﻠـﻢ اﻟﻜﻮﻧﻴﺎت اﻟﺤﺪﻳﺚ ﻣﻨﺬ ﻓﱰة ﺣﻴـﺚ ﻧﺠـﺢ ﰲ وﺻـﻒ اﻟﺒﻨـﻰ واﺳﻌﺔ اﻟﻨﻄﺎق ﰲ اﻟﻜﻮن . ﺑﺪﻗﺔ ﻳﻘﱰح ﻫﺬا اﻟﻨﻤﻮذج أن 95 % ﻣﻦ اﻟﻜﻮن ﻳﺘﻜـﻮن ﻣـﻦ ا ـﺎدة ا ﻈﻠﻤـﺔ )25 (% واﻟﻄﺎﻗـﺔ ا ﻈﻠﻤــﺔ )70 (%- وﻫﻤــﺎ ﻣﺎدﺗــﺎن ﻏﺎﻣﻀــﺘﺎن ﻻ ﺗــﺰال ﻃﺒﻴﻌ ﺘﻬﻤﺎ ﻣﺠﻬﻮﻟﺔ . أﻣﺎ ا ﺎدة اﻟﻌﺎدﻳﺔ ﻓﺘﻤﺜﻞ 5 % ﻓﻘﻂ ﻣﻦ اﻟﻜﻮن ﻳ . ﻌﺘﻘﺪ أن اﻟﻄﺎﻗﺔ ا ﻈﻠﻤﺔ ا ﻤﺜﻠـﺔ ﺑﺎﻟﺜﺎﺑـﺖ اﻟﻜـﻮﻧﻲ ) Λ ( ﻫﻲ ا ﺤﺮك ﻟﻠﺘﻮﺳﻊ ا ﺘﺴﺎرع ﻟﻠﻜـﻮن ﻣﺤﺎﻓﻈـﺔ ﻋـﲆ ﻛﺜﺎ ﻓﺔ ﻃﺎﻗﺔ ﺛﺎﺑﺘﺔ ﻣﻊ ﻣﺮور اﻟﻮﻗﺖ وﻣ ﻊ ذﻟﻚ ﺗ ﺸـ ﻧﺘـﺎﺋﺞ ﺟﺪﻳﺪة ﻣﻦ ﻣﺴﺢ اﻟﻄﺎﻗﺔ ا ﻈﻠﻤﺔ ﻋ ( إس. إي.دي) ﺮﺿـﺖ ﰲ ــ ورﻗﺔ ﺑﺤﺜﻴﺔ ﻧـ ـ ﴩت ﻋـﲆ ا ﻮﻗـﻊ اﻻﻟﻜﱰوﻧـﻲ arXiv وﰲ ﻣﺤﺎدﺛﺎت ﰲ ﻗﻤﺔ اﻟﻔﻴﺰﻳـﺎء اﻟﻌﺎ ﻴـﺔ ﻟﻠﺠﻤﻌﻴـﺔ اﻟﻔﻴﺰﻳﺎﺋﻴـﺔ اﻷﻣﺮﻳﻜﻴﺔ ﰲ أﻧﻬﺎﻳﻢ ﰲ ﻛﺎﻟﻴﻔﻮرﻧﻴﺎ إﱃ ﺗﻐـ اﻻﻓـﱰاض ﻣﻤـﺎ ﻳﺸ إﱃ أن اﻟﻄﺎﻗﺔ ا ﻈﻠﻤﺔ ﻗﺪ ﺗﺘﻄﻮر ﻣـﻊ ﻣـﺮور اﻟﻮﻗـﺖ . ﺗﺘﻮاﻓﻖ ﻫﺬه اﻟﻨﺘﺎﺋﺞ ﻣـﻊ اﻟﺪراﺳـﺎت اﻟﺴـﺎﺑﻘﺔ ﻣﻤـﺎ ﻳﻌـﺰز أﻫﻤﻴﺘﻬﺎ ﺎً ﺗﻌﺎوﻧ ﺴﺢ ﻫﺬا ا ﻌﺪ ﻳ. ﺎً دوﻟﻴ ﻳﻀﻢ أﻛ ﺜـﺮ ﻣـﻦ 400 ﻋﺎﻟﻢ ﻣﻦ أﻛﺜﺮ ﻣـﻦ 25 ﻣﺆﺳﺴـﺔ ﺑﻘﻴـﺎدة ﻣﺨﺘـﱪ ﻓ ﻣـﻲ اﻟﻮﻃﻨﻲ ﻟﻠﻤﴪﻋﺎت اﻟﺘﺎﺑﻊ ﻟﻮزارة اﻟﻄﺎﻗﺔ اﻷﻣﺮﻳﻜﻴﺔ . أُﺟﺮي ﻣﺴﺢ اﻟﻄﺎﻗـﺔ ا ﻈﻠﻤـﺔ إس. إي.دي) ( ﺑﺎﺳـﺘﺨﺪام ﻛـﺎﻣ ا ﺻﻨﻌﺘﻬﺎ وزارة اﻟﻄﺎﻗﺔ اﻷﻣﺮﻳﻜﻴﺔ ﺑﺪﻗﺔ 570 ﻣﻴﺠـﺎ ﺑﻜﺴـﻞ ــــ ﻣﺠﻠﺔ FreeAstronomy ﺎﻟﻌﺮ ﺔ 44 ﺗ ﺎ ﻨﺎت ﻣﺤﺘﻤﻠﺔ ﻓﻲاﻟﻨﻤﻮذج اﻟ ﻮﻧﻲاﻟﻘ ﺎﺳﻲ : ﻘﻠﻢ ﺟﻮزيﻓ ﻨﺴﻜﻲ و ﻓﺮ ﺎﻧﺪو ﺗﻮر ﺴ ﻼ ﻷﺑﺤﺎث اﻟﻔﻠﻚ اﻟ ﺼﺮيوﺗﺤﺖ اﻷ ﻤﺮ اﻟﻤﺨﺘ اﻟﻮﻃ ) ﻧﻮﻳﺮﻻب (