BEGIN:VCALENDAR VERSION:2.0 PRODID:-//linuxsoftware.nz//NONSGML Joyous v1.4//EN BEGIN:VEVENT SUMMARY:Testing the Geometry of the Universe with Curvature-Consistency Re lations DTSTART:20260910T143000Z DTEND:20260910T160000Z DTSTAMP:20260916T104011Z UID:6bb71d04-1bf2-434a-8329-dac151d9911d SEQUENCE:2 CREATED:20260909T091610Z DESCRIPTION:The Lambda cold dark matter (LCDM) cosmological model faces in creasingly significant and robust tensions among independent cosmological measurements\, prompting renewed scrutiny of its foundational assumptions. While general relativity and the nature of dark energy are now routinely tested with cosmological surveys\, less progress has been made testing the spacetime geometry at the largest scales\, and in particular testing the assumption that observables (distances\, redshifts\, etc.) on the largest scales are described by a single Friedmann-Lemaître-Robertson-Walker (FLR W) metric.This can however be done employing curvature-consistency tests. Such tests utilize that spatial curvature within the FLRW metrics take a p articularly simple form\, which implies that certain constraint equations for cosmological observables must be satisfied if the FLRW ansatz is indee d correct. In non-FLRW models\, these constraints are generally expected t o be violated\, but theoretical predictions for the signature of their vio lation in non-FLRW scenarios have been lacking in the literature.I will pr esent recent theoretical developments on curvature-consistency tests\, wit h focus on their signatures within physically motivated non-FLRW scenarios . In particular\, I will present smoking gun signatures for back reaction universe models (where the large-scale expansion of the cosmology is diffe rent from FLRW) and the so-called Dyer-Roeder universes (where the optical properties of the cosmology deviate from the expectations of FLRW). I wil l finally comment on recent observational constraints of curvature-consist ency tests and their implications. LAST-MODIFIED:20260909T091626Z LOCATION:DF Seminar Room (2-8.3)\, 2nd floor of Physics Building URL:http://df.vps.tecnico.ulisboa.pt/pt/eventos/testing-the-geometry-of-th e-universe-with-curvature-consistency-relations/ X-ALT-DESC;FMTTYPE=text/html:

The Lambda cold dar k matter (LCDM) cosmological model faces increasingly significant and robu st tensions among independent cosmological measurements\, prompting renewe d scrutiny of its foundational assumptions. While general relativity and t he nature of dark energy are now routinely tested with cosmological survey s\, less progress has been made testing the spacetime geometry at the larg est scales\, and in particular testing the assumption that observables (di stances\, redshifts\, etc.) on the largest scales are described by a singl e Friedmann-Lemaître-Robertson-Walker (FLRW) metric.

This can however be done employing curvature-consistency tes ts. Such tests utilize that spatial curvature within the FLRW metrics take a particularly simple form\, which implies that certain constraint equati ons for cosmological observables must be satisfied if the FLRW ansatz is i ndeed correct. In non-FLRW models\, these constraints are generally expect ed to be violated\, but theoretical predictions for the signature of their violation in non-FLRW scenarios have been lacking in the literature.

I will present recent theoretical developmen ts on curvature-consistency tests\, with focus on their signatures within physically motivated non-FLRW scenarios. In particular\, I will present sm oking gun signatures for back reaction universe models (where the large-sc ale expansion of the cosmology is different from FLRW) and the so-called D yer-Roeder universes (where the optical properties of the cosmology deviat e from the expectations of FLRW). I will finally comment on recent observa tional constraints of curvature-consistency tests and their implications.< /p> END:VEVENT END:VCALENDAR