#cosmictopology — Public Fediverse posts

Did you know that the Universe is expanding at a rate of about 2.2 attoHertz?

What is our current model of the Universe? What is the #ShapeOfTheUniverse (curvature + topology)? Is the Universe finite or infinite? How did it begin? How will it end? What are #DarkEnergy and #DarkMatter? Why might you want to study these questions at #NCU in #Toruń, the birthplace of Copernicus?

See Dawid Jankowski's interview with me talking about #cosmology: https://peertube.stream/w/6jeseftBEkPVppSmcFyW7q

#CosmicTopology @cosmology

Did you know that the Universe is expanding at a rate of about 2.2 attoHertz?

What is our current model of the Universe? What is the #ShapeOfTheUniverse (curvature + topology)? Is the Universe finite or infinite? How did it begin? How will it end? What are #DarkEnergy and #DarkMatter? Why might you want to study these questions at #NCU in #Toruń, the birthplace of Copernicus?

See Dawid Jankowski's interview with me talking about #cosmology: https://peertube.stream/w/6jeseftBEkPVppSmcFyW7q

#CosmicTopology @cosmology

Did you know that the Universe is expanding at a rate of about 2.2 attoHertz?

What is our current model of the Universe? What is the #ShapeOfTheUniverse (curvature + topology)? Is the Universe finite or infinite? How did it begin? How will it end? What are #DarkEnergy and #DarkMatter? Why might you want to study these questions at #NCU in #Toruń, the birthplace of Copernicus?

See Dawid Jankowski's interview with me talking about #cosmology: https://peertube.stream/w/6jeseftBEkPVppSmcFyW7q

#CosmicTopology @cosmology

Did you know that the Universe is expanding at a rate of about 2.2 attoHertz?

What is our current model of the Universe? What is the #ShapeOfTheUniverse (curvature + topology)? Is the Universe finite or infinite? How did it begin? How will it end? What are #DarkEnergy and #DarkMatter? Why might you want to study these questions at #NCU in #Toruń, the birthplace of Copernicus?

See Dawid Jankowski's interview with me talking about #cosmology: https://peertube.stream/w/6jeseftBEkPVppSmcFyW7q

#CosmicTopology @cosmology

Did you know that the Universe is expanding at a rate of about 2.2 attoHertz?

What is our current model of the Universe? What is the #ShapeOfTheUniverse (curvature + topology)? Is the Universe finite or infinite? How did it begin? How will it end? What are #DarkEnergy and #DarkMatter? Why might you want to study these questions at #NCU in #Toruń, the birthplace of Copernicus?

See Dawid Jankowski's interview with me talking about #cosmology: https://peertube.stream/w/6jeseftBEkPVppSmcFyW7q

#CosmicTopology @cosmology

Gday @quasilocal :)

In principle you can follow a hashtag such as #TopologicalAcceleration or #CosmicTopology . I haven't tried following hashtags (yet), though I should for some of the more specialist topics.

In the desktop browser interface, you can follow a selection of hashtags (at least one of set 1, all of set 2, none of set 3, where you define the elements of the three sets) - I've done this for some time and find it more or less on-topic and not overwhelmed by overenthusiastic posters.

@[email protected]

As a clickable link, the pdf is at

https://cosmo.torun.pl/~boud/Roukema20220203ASGRG.pdf

and an extended version, presented on 1 October 2022 at Świnoujście - see https://cosmo.usz.edu.pl/AutumnWorkshop22 is at

https://cosmo.torun.pl/~boud/Roukema20221001AWSwino.pdf

#CosmicTopology #Cosmology

@cartographer @stephenserjeant @NatureAstronomy

Could galaxy motions detect #CosmicTopology ?

Yes: #TopologicalAcceleration is known since 2007 [1]. But Newtonian approx. to gravity in S^3 requires replacing

F ∝ 1/r^2

by

F ∝ 1/(sin r)^2

and 1/(sin r)^2 in S^3 gives paradox: repulsive point mass @antipode [2]. A better Newtonian-like limit is needed. For a hint see [3][4]. :)

[1] https://ui.adsabs.harvard.edu/abs/2007A%26A...463..861R

[2] https://ui.adsabs.harvard.edu/abs/2009A%26A...502...27R

[3] https://arxiv.org/abs/2201.09102

[4] https://codeberg.org/boud/topoaccel

@stephenserjeant Welcome to the #Fediverse :).

For another step towards intellectual freedom, see https://mastodon.technology/@conservancy/108566696125594772 .

If you're curious about ongoing questions in #CosmicTopology (RAS one-day meeting, a few years ago), see https://arxiv.org/abs/2201.09102 .

EAS and hybrid meetings: yes to hybrid meetings, but no to Zoom/Webex/MSTeams or other #WalledGarden servers and non-free software.
#BigBlueButton and #Jitsi are #FreeSoftware that astronomers should use and support.