Geraint F. Lewis
@cosmichorizons.bsky.social
Cosmologist & Galactic Archaeologist at
@Sydney_Uni. Proud Silurian, Australian immigrant, & author of books about the strange universe we find ourselves in!
@Sydney_Uni. Proud Silurian, Australian immigrant, & author of books about the strange universe we find ourselves in!
They don't do Guy Fawkes in Australia (but I discovered this weekend that they do in New Zealand). But do we celebrate because he was captured, and the gunpowder plot failed, or because he tried?
November 5, 2025 at 10:39 PM
They don't do Guy Fawkes in Australia (but I discovered this weekend that they do in New Zealand). But do we celebrate because he was captured, and the gunpowder plot failed, or because he tried?
Oh I just give up (this was on ABC in Australia, source apparently NASA). And every time anyone calls these moons by a stupid name like Beaver, a small astronomy fairy dies.
November 5, 2025 at 10:22 PM
Oh I just give up (this was on ABC in Australia, source apparently NASA). And every time anyone calls these moons by a stupid name like Beaver, a small astronomy fairy dies.
Dear palaeontologist - please feel free to chat to astronomers about how orbits work so you don’t end up with gaffes like this in your books,
November 5, 2025 at 7:11 PM
Dear palaeontologist - please feel free to chat to astronomers about how orbits work so you don’t end up with gaffes like this in your books,
I am dipping my toes into Fast Radio Burst research, and I discovered they have a "sad trombone effect".
November 5, 2025 at 6:52 AM
I am dipping my toes into Fast Radio Burst research, and I discovered they have a "sad trombone effect".
Getting ready for my talk in Auckland tomorrow night
October 30, 2025 at 10:21 PM
Getting ready for my talk in Auckland tomorrow night
Getting one of these off a group of students you have supervised for a year really means something to me.
October 28, 2025 at 8:13 PM
Getting one of these off a group of students you have supervised for a year really means something to me.
Time to start posting current reading
October 24, 2025 at 9:50 PM
Time to start posting current reading
Reposted by Geraint F. Lewis
Today, people across the world remember one of the greatest tragedies in Welsh history - the 1966 Aberfan disaster - which left a small mining village robbed of an entire generation
Cofiwn: World remembers Aberfan disaster
Stephen Price Today, people across the world remember one of the greatest tragedies in Welsh history – the 1966 Aberfan disaster – which left a small mining village robbed of an entire generation. On ...
nation.cymru
October 21, 2025 at 7:46 AM
Today, people across the world remember one of the greatest tragedies in Welsh history - the 1966 Aberfan disaster - which left a small mining village robbed of an entire generation
I authored a new video for the History of the Universe on just what the Higgs boson is, and how it could destroy the universe.
#scicomm #physics #cosmology #particlephysics
youtu.be/JNgEMyTxB8E?...
#scicomm #physics #cosmology #particlephysics
youtu.be/JNgEMyTxB8E?...
Did We Just Discover The Universe's Greatest Weakness?
YouTube video by History of the Universe
youtu.be
October 12, 2025 at 3:29 AM
I authored a new video for the History of the Universe on just what the Higgs boson is, and how it could destroy the universe.
#scicomm #physics #cosmology #particlephysics
youtu.be/JNgEMyTxB8E?...
#scicomm #physics #cosmology #particlephysics
youtu.be/JNgEMyTxB8E?...
Thursday afternoon deep thought...
September 11, 2025 at 3:48 AM
Thursday afternoon deep thought...
Reposted by Geraint F. Lewis
🤓 Cosmic Perfection Won’t Last.
Cosmic Perfection Won’t Last.
YouTube video by Life & The Earth
www.youtube.com
September 6, 2025 at 7:22 PM
🤓 Cosmic Perfection Won’t Last.
Even after being in this country for quarter of a century, bumping into these guys still make me smile.
August 30, 2025 at 7:49 AM
Even after being in this country for quarter of a century, bumping into these guys still make me smile.
Having fun "vibe mathing" with copilot tonight. I think I'm at the limit of known mathematics and about to break through into something new!
August 24, 2025 at 8:01 AM
Having fun "vibe mathing" with copilot tonight. I think I'm at the limit of known mathematics and about to break through into something new!
The greatest trick the Devil ever pulled was convincing Mac PowerPoint users that they have to upload their slides to the session computer before their talk and that their fonts and animations will not be screwed up.
August 17, 2025 at 10:34 PM
The greatest trick the Devil ever pulled was convincing Mac PowerPoint users that they have to upload their slides to the session computer before their talk and that their fonts and animations will not be screwed up.
Spotted at Central Station, Sydney - that's quite a train ride.
August 13, 2025 at 6:34 AM
Spotted at Central Station, Sydney - that's quite a train ride.
Spotted at Central Station, Sydney - that's quite a train ride.
August 13, 2025 at 6:32 AM
Spotted at Central Station, Sydney - that's quite a train ride.
Reposted by Geraint F. Lewis
Come on down on Saturday to hear a bunch of awesome science talks - including one on how we are building huge radio telescopes and finding tiny stars!
☄️🔭🧪
☄️🔭🧪
Science at the Museum is happening at the Chau Chak Wing Museum on Saturday 16th and Sunday 17th August! Join us as we team up again with the museum for a program loaded with activities for the whole family! #MathSky #NationalScienceWeek
mathematical-research-institute.sydney.edu.au/event/scienc...
mathematical-research-institute.sydney.edu.au/event/scienc...
August 12, 2025 at 4:41 AM
Come on down on Saturday to hear a bunch of awesome science talks - including one on how we are building huge radio telescopes and finding tiny stars!
☄️🔭🧪
☄️🔭🧪
Reposted by Geraint F. Lewis
For those in Sydney on Saturday afternoon, I will be speaking all about cosmology and the Big Bang at this event at the very nice Chau Chak Wing Museum
Science at the Museum is happening at the Chau Chak Wing Museum on Saturday 16th and Sunday 17th August! Join us as we team up again with the museum for a program loaded with activities for the whole family! #MathSky #NationalScienceWeek
mathematical-research-institute.sydney.edu.au/event/scienc...
mathematical-research-institute.sydney.edu.au/event/scienc...
August 12, 2025 at 3:40 AM
For those in Sydney on Saturday afternoon, I will be speaking all about cosmology and the Big Bang at this event at the very nice Chau Chak Wing Museum
Not sure the word "Even" is necessary in this headline!
August 13, 2025 at 12:14 AM
Not sure the word "Even" is necessary in this headline!
Dear teachers of special relativity - please stop telling students that special relativity can't handle acceleration and they have to wait for general relativity for that. ThX
August 9, 2025 at 9:58 PM
Dear teachers of special relativity - please stop telling students that special relativity can't handle acceleration and they have to wait for general relativity for that. ThX
Being the 80th anniversary of the bombing of #Hiroshima, this image is doing the rounds as a flash shadow of a person. However, I suspect this is not what this is, as it is much more distinct than other shadows and doesn't appear to have a history before 10-15 yrs ago. Anyone have details?
August 6, 2025 at 12:21 PM
Being the 80th anniversary of the bombing of #Hiroshima, this image is doing the rounds as a flash shadow of a person. However, I suspect this is not what this is, as it is much more distinct than other shadows and doesn't appear to have a history before 10-15 yrs ago. Anyone have details?
I'm going to be talking at the Southern Highlands Branch of the Royal Society of New South Wales on the 16th October in Mittagong (a wonderful part of Australia). If you want to hear about gravitational lenses, come along.
www.royalsoc.org.au/events/south...
www.royalsoc.org.au/events/south...
Southern Highlands Branch Meeting: 2025-9 - The Royal Society of NSW
“Peering at the Sky with Nature’s Telescopes” Professor Geraint Lewis FRSN FLSW Sydney Institute of Astronomy School of Physics University of Sydney Date: Thursday, 16 October, 6.30–7.30 pm AEST […...
www.royalsoc.org.au
July 30, 2025 at 6:25 AM
I'm going to be talking at the Southern Highlands Branch of the Royal Society of New South Wales on the 16th October in Mittagong (a wonderful part of Australia). If you want to hear about gravitational lenses, come along.
www.royalsoc.org.au/events/south...
www.royalsoc.org.au/events/south...
Did anyone get the memo that we should be rethinking the origins of the universe? I seem to have missed it.
July 29, 2025 at 12:23 AM
Did anyone get the memo that we should be rethinking the origins of the universe? I seem to have missed it.
A little Saturday afternoon culture at the Parramatta Riverside Theatre - and excellent play!
July 26, 2025 at 8:56 AM
A little Saturday afternoon culture at the Parramatta Riverside Theatre - and excellent play!
Loving the Yalta episode in @empirepoduk.bsky.social but I have to take issue at your claim of the British love of Churchill. Where I grew up - the Welsh Valleys - he is not a popular figure and is still spoken about negatively (& often with swear words).
www.walesonline.co.uk/news/politic...
www.walesonline.co.uk/news/politic...
The towns in Wales where Churchill was loathed
Many in Tonypandy and Llanelli saw Churchill as someone who would use troops against workers
www.walesonline.co.uk
July 16, 2025 at 12:59 AM
Loving the Yalta episode in @empirepoduk.bsky.social but I have to take issue at your claim of the British love of Churchill. Where I grew up - the Welsh Valleys - he is not a popular figure and is still spoken about negatively (& often with swear words).
www.walesonline.co.uk/news/politic...
www.walesonline.co.uk/news/politic...