Dark Matter Week: Celebrating the Unseen Force
On October 31, Dark Matter Day is celebrated worldwide. On this occasion, Tartu Observatory and Old Observatory of University of Tartu have created a special program where science and art come together to shed light on the universe’s greatest mystery – dark matter.
Dark matter is the Universe's invisible superstar! Even though we can't see it, we know that dark matter is all around us and makes up a whole quarter of the Universe's mass and energy. And that's not all — the Universe's expansion is driven by a mysterious force called dark energy, which takes up as much as 70 percent of the Universe. This means that a large part of the Universe is still a big mystery waiting to be solved!
Studies of dark matter are closely linked to Estonia and Tõravere. Read the article "Five decades of missing matter".
From October 29 to November 5, we will celebrate Dark Matter Week with public lectures aimed at exploring the cosmic mysteries.
As a special event, an art exhibition will open in November at Tartu Observatory in Tõravere.
::: Program :::
On October 29 at 6.15 PM at the Old Observatory (Uppsala 8, Tartu)
Manuel Hohmann, a Associate Professor of Theoretical Physics at University of Tartu, will discuss three stories about the mysteries, questions, and possible answers regarding the dark universe.
Astronomical observations show that visible matter, which includes stars, planets, and us, makes up only 5% of the universe's matter content. About 25% is dark matter: an unknown source of gravity that neither emits nor absorbs light, and which we can only detect through its effects on the movement of visible matter.
Even more challenging is the detection of dark energy, which makes up the remaining 70% of the universe, and whose only observable effect is the accelerating expansion of the universe. Observations clearly indicate the amounts of these dark universe components and the properties they must have, but they do not answer the question of what the dark universe is made of: are they unknown heavy particles, black holes, vacuum energy, or something else? This is perhaps the most famous mystery of modern physics. Since the dark universe has so far only manifested itself through gravity, the question arises whether our understanding of gravity is correct.
The public lecture video is available on UTTV. The lecture is in Estonian.
Join the Facebook event.
On November 4 at 7 PM at Must Puudel (Kuninga 4, Tallinn)
Jorge Sanchez Almeida, a Professor at Canary Islands Institute of Astrophysics, will challenge the conventional view of dark matter in his talk.
The dark matter is a fundamental ingredient in our model of Universe. It makes 85% of the total mass and, thus, thanks to its gravity, the tiny density fluctuations produced during the Big Bang grow to develop all the structures that we see today (stellar clusters, galaxies, galaxy clusters, and so on). The current cosmological model, which otherwise is extremely successful, assumes the dark matter to be made of particles interacting with each other and with the ordinary matter only through gravity. Such minimal assumption on the properties of dark matter just hides our ignorance of what dark matter really is. We still have no clue, despite the tremendous effort to reveal its physical nature made by thousands of physicists and astrophysicists working during the last 40 years. Our team has found observational evidence that dark matter is not as assumed by the cosmological model. 'Real' dark matter has to do something else, e.g., if it were particles, in addition to feeling gravity, they collide with each other like billiard balls. I will describe how we came up with this conclusions, and the implications it has constraining the unknown nature of dark matter. In particular, I would mention the possibility that dark matter is not a single particle but a family of particles living next to us. They have remained noticed because they have their own charges and suffer their own forces, producing light-like particles we cannot detect with instruments made of ordinary matter.
The public lecture is with free entrance and is held in English.
Join the Facebook event.
On November 5 at 6.15 PM at the Old Observatory (Uppsala 8, Tartu)
Science philosopher Enn Kasak will discuss in his lecture how the deeper inclusion of quantum theory in describing the universe compels us to rethink concepts such as reality, spacetime, and matter — both in its "dark" and "light" forms.
The public lecture lecture video is available on UTTV. The lecture is in Estonian.
Join the Facebook event.
In November at Tartu Observatory (Observatooriumi 1, Tõravere)
Art exhibition by Kärt Summatavet, Navitrolla ja Maret Einasto is set to open.
