Statement by Finnish Astronomers and Astrophysicists on Harassment

We, astronomers and astrophysicists from Finland and in Finland, strongly condemn harassment and discrimination. This includes but is not limited to harassment or discrimination based on sex, gender, sexual orientation, race, or disability. Harassment can take the form of unwanted sexual attention, bullying, coercion, or the creation of an unsafe or hostile work environment, especially in the presence of imbalances of power. Our own academic community is no exception.

Harassment is a serious offence that too often goes unreported and unchallenged. When  victims come forward, they must be able to rely on our support. We must address the issue head-on. Otherwise, we not only enable harassers, but also send a devastating message to the individuals who have been harassed – and whose careers are often destroyed or seriously disrupted – as well as to the whole community.

Our concern and solidarity is first with victims of harassment, and with the right of all staff and students to work in a healthy and safe environment. And while we also recognise the possibility of rehabilitation, it can only be at the end of a process that begins with an acknowledgement of the offense, and taking responsibility for the harm caused.

The Finnish astronomical and astrophysical community is diverse and international, and it is also deeply connected. It strives on principles of fairness and equal opportunities. Harassment or discrimination threaten our community and our way of working together. They have no place here.

Original statement online: goo.gl/LJ4GC6

Finnish or Finland-based astronomers or astrophysicists, please use this form to sign: https://goo.gl/forms/TSqOjg1pIq1xHtNA2

Other academics, please use this form to show your support: https://goo.gl/forms/GQ0oImljndVEl68q1

The APOSTLE collaboration

The APOSTLE collaboration is “A Project Of Simulating The Local Environment”.

An offshoot of the EAGLE collaboration, it was started by myself, Carlos Frenk, Azadeh Fattahi and Julio Navarro in 2013, and has now grown to a large international collaboration. To date, more than 20 papers based directly on APOSTLE data have been written by more than 30 different co-authors from Argentina, Belgium, Canada, Chile, China, Finland, Germany, Iran, Ireland, Italy, Mexico, the Netherlands, Poland, Romania, Switzerland, the UK and the US.

Click below for a list of APOSTLE papers published to date. We also keep a repository for ongoing projects (password required). If you are interested in using APOSTLE data for your own project, please send me an email (till+DOT+sawala+AT+helsinki+DOT+fi)

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Project SIBELIUS

Jean Sibelius 1913

Jean Sibelius by Daniel Nyblin, [Public domain], via Wikimedia Commons

Music to our ears: CSC, the Finnish national supercomputing centre, have approved our Grand Challenge application for the SIBELIUS project: simulations beyond the Local Universe. Lots of exciting things to come!

Beyond LCDM – science, scenery and a prize!

From January 14-17, Oslo’s famous Holmenkollen played a fitting backdrop to the remarkable Beyond LCDM conference, an assembly of cosmologists from all over the world, working within and without the so-called standard model.

The conference venue on the Holmenkollen View over Oslo from the Holmenkollen

For those of us who have learned to refer to LCDM as the “standard model” of cosmology, it gave an insight into the range of alternatives out there, while those in the community hoping to slay the LCDM dragon were reminded that, outrageous and ugly as it may seem, LCDM continues to be notoriously tough to beat with observational evidence.

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Dirac Day

Dirac Day is being held in Durham, and I have prepared another augmented reality poster using DARO (This time exploring the state container, which allows for much greater flexibility). As before, the augmented reality elements will work if the poster is viewed on your screen just like the printed poster.

If you have just scanned the QR code using your phone, but you are reading this message, you probably have not installed the DARO viewer yet. Please speak to me – I’ll be happy to lend you my tablet. Alternatively, you can download the latest version of DARO for your phone from the DARO project website. I can also help you install it.

DARO is being developed in Durham by Jascha Schewtschenko. If you are interested, please contact him via the DARO website.

IAU Symposium 311: Galaxy Masses as Constraints of Formation Models

For IAU Symposium 311, I have prepared an augmented reality poster using DARO. The augmented reality elements will work if the poster is viewed on your screen just like the printed poster.

If you have just scanned the QR code using your phone, but you are reading this message, you probably have not installed the DARO viewer yet. Please speak to me at the IAU meeting – I’ll be happy to lend you my tablet. Alternatively, you can download the latest version of DARO for your phone from the DARO project website:

DownloadDaro DownloadDARO.vuforia

 

DARO is developed by Jascha Schewtschenko at Durham University. By downloading and installing DARO, you agree to its license. In the future, please always visit the project website for the latest version.

Paper: which low mass halos host galaxies?

We have just written a new paper, where we study the impact of reionization on galaxy formation in the Local Group using computer simulations.

We find that most of the dark matter halos of similar mass to the observed dwarf galaxies are in fact completely dark; unable to form stars after reionization heats up the intergalactic gas. Those halos that do form stars are not only rare, but also special: they formed much earlier than “typical” halos, and if they are satellites, they follow different orbits than a pure dark matter simulation would predict. We conclude that if we want to understand dark matter by only studying the halos that host the observable galaxies, we have to be aware that we are dealing with a very special selection. We call them The Chosen Few.

V1_MR_reion_z0 V1_MR_no_reion_z0   From Fig. 1: Gas density in the Local Group simulation with reionization (left) and without reionization (right). Without reionization, many more “clumps” of gas can cool and form dwarf galaxies, but with reionization included, only a small fraction of low-mass halos keep enough cold gas for star formation, leaving most dark matter halos completely dark.

If you’d like to read more, please take a look at our paper. Also, see Durham University’s press release.

Collaborators: Carlos S. FrenkAzadeh FattahiJulio F. NavarroTom TheunsRichard G. BowerRobert A. CrainMichelle FurlongAdrian JenkinsMatthieu SchallerJoop Schaye

 

In the news: cosmic own goal leaves galaxies dark

Our paper “The chosen few: the low mass halos that host faint galaxies” has been in the news!

Collaborators: Carlos S. FrenkAzadeh FattahiJulio F. NavarroTom TheunsRichard G. BowerRobert A. CrainMichelle FurlongAdrian JenkinsMatthieu SchallerJoop Schaye

 

English

  • The Daily Mail Online: Are we on the brink of finding dark matter?
  • Phys.org: ‘Cosmic own goal’ another clue in hunt for dark matter
  • Motherboard.vice.com: Dark Matter Halos are Sad Would-Be Galaxies
  • Red OrbitIn the Hunt For Dark Matter, New Simulations Show Evolution Of “Local Universe”
  • ANI News: Understanding formation of galaxies could solve mystery of dark matter
  • Science World Report: Supercomputer Simulations Chart the Evolution of the Local Universe
  • Science 2.0: Just In Time For The World Cup, The Cosmos Scores A Dark Matter Own Goal

Dutch

  • Astronomie.nl: Eerste sterren hinderden de vorming van sterrenstelsels

Spanish

  • Tendencias 21: Nuevos descubrimientos nos acercan a la materia oscura

Italian

  • INAF: Aloni sterili e materia oscura

 

Sources