Delta på disputasen
Denne disputasen og prøveforelesningen vil gjennomføres 100% fysisk. Vennligst vær tidlig ute, ettersom dørene stenger akkurat på tide.
Delta på prøveforelesning - 2. november kl. 10:15 (Aud. 209, Svein Rosselands Hus)
"Neutrinos and the CMB"
Kreeringssammendrag
Den kosmiske bakgrunnsstrålingen er det eldste lyset i Universet og ved å måle mønstrene i dette lyset kan vi ikke bare lære hva universet er laget av, men også potensielt finne nye fundamentale partikler og krefter. Dette arbeidet tar for seg hvordan vi kan bruke dette lyset til måle universets geometriske form, og vi presenterer bevis for en ny fysisk kraft kalt kosmisk dobbeltbrytning.
Hovedfunn:
The cosmic microwave background (CMB) is not just the oldest light in the Universe but also the oldest polarized light. By measuring its patterns, we can learn large amounts of information about the origin of the Universe and its content. This work focuses on some of the allowed ''shapes'', or more precisely, topologies of the Universe. We describe their potential patterns in the CMB, showing that the shape of the Universe is likely impossible to be measured in the CMB if its size is too large.
We also provide evidence for cosmic birefringence, a potentially new phenomenon that might have rotated the linear polarization of the CMB photons. This work provides evidence for the signal being independent of the energy of the photons, which is consistent with a new fundamental particle called axions. In addition, we show that the signal is unlikely to be attributed to systematic effects or astrophysical foregrounds, and that the rotation must have started after the epoch when the CMB was created. If proven to be real, it would be revolutionary for cosmology and particle physics, and it could shed light on what either dark matter or dark energy is.
