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![What shape is the ocean on a cubical planet?](https://static.wixstatic.com/media/4c8c3d_28af0065366549a1864c670b2ee678a4~mv2.png/v1/fill/w_454,h_341,fp_0.50_0.50,q_95,enc_auto/4c8c3d_28af0065366549a1864c670b2ee678a4~mv2.webp)
What shape is the ocean on a cubical planet?
Here's a repost of something I wrote almost a decade ago, wondering what shape an ocean would take on a non-spherical planet. I do hope...
![The Rare Earth Hypothesis](https://static.wixstatic.com/media/4c8c3d_08ee15dc2a9c49a187944f66dd201e0e~mv2.png/v1/fill/w_454,h_341,fp_0.50_0.50,q_95,enc_auto/4c8c3d_08ee15dc2a9c49a187944f66dd201e0e~mv2.webp)
The Rare Earth Hypothesis
We are told that the Earth is a typical planet, orbiting a typical star, at nowhere in particular in the universe. But is it? In the next...
![Future Universe: Part 2](https://static.wixstatic.com/media/4c8c3d_155ccd955b0340aeb34490a370b7bcf0~mv2.png/v1/fill/w_454,h_341,fp_0.50_0.50,q_95,enc_auto/4c8c3d_155ccd955b0340aeb34490a370b7bcf0~mv2.webp)
Future Universe: Part 2
I continue my discussion with Dr Karl about the Future of the Universe. However, we are still digging through the past to understand why...
![Unknown Pleasures](https://static.wixstatic.com/media/4c8c3d_bbbf22c053d4453d89d421555fd676cd~mv2.png/v1/fill/w_454,h_341,fp_0.50_0.50,q_95,enc_auto/4c8c3d_bbbf22c053d4453d89d421555fd676cd~mv2.webp)
Unknown Pleasures
I am part of the GALAH Survey, a project to observe hundreds of thousands of stars in the Milky Way to try and piece together its...
![](https://static.wixstatic.com/media/4c8c3d_fefa65de3a7343b8bba2be71bb765ae1~mv2.jpg/v1/fill/w_250,h_250,fp_0.50_0.50,q_30,blur_30,enc_auto/4c8c3d_fefa65de3a7343b8bba2be71bb765ae1~mv2.webp)
![The German Tank Problem (Part II)](https://static.wixstatic.com/media/4c8c3d_fefa65de3a7343b8bba2be71bb765ae1~mv2.jpg/v1/fill/w_454,h_341,fp_0.50_0.50,q_90,enc_auto/4c8c3d_fefa65de3a7343b8bba2be71bb765ae1~mv2.webp)
The German Tank Problem (Part II)
Again, a repost of something I wrote about in 2012, the German Tank Problem. This time with a twist. TL:DR - the mathematicians win...
![Space magnets, asteroids, coral sex](https://static.wixstatic.com/media/4c8c3d_fdb806a5eb8446a186cc0c89837e880d~mv2.png/v1/fill/w_454,h_341,fp_0.50_0.50,q_95,enc_auto/4c8c3d_fdb806a5eb8446a186cc0c89837e880d~mv2.webp)
Space magnets, asteroids, coral sex
Do magnets work in outer space? What would happen if you opened a jar from space on Earth? Do germs have the ability to move on their...
![The Future History of the Universe](https://static.wixstatic.com/media/4c8c3d_6539313b6f5749eaa6d16a807ab0ebfa~mv2.png/v1/fill/w_454,h_341,fp_0.50_0.50,q_95,enc_auto/4c8c3d_6539313b6f5749eaa6d16a807ab0ebfa~mv2.webp)
The Future History of the Universe
What is the future history of the universe? To answer this question, we have to look firstly into the past. A new chat with Doctor Karl...
![The German Tank Problem (Part I)](https://static.wixstatic.com/media/4c8c3d_8ef551d6dcb340369e466ee846690d73~mv2.png/v1/fill/w_454,h_341,fp_0.50_0.50,q_95,enc_auto/4c8c3d_8ef551d6dcb340369e466ee846690d73~mv2.webp)
The German Tank Problem (Part I)
As part of my plan to get back into blogging, here's a repost from 2011 discussing a classic statistical problem. I followed it up a year...
![](https://i.ytimg.com/vi/3Wg1mRPRg0c/maxresdefault.jpg)
![The Cosmic Revolutionary's Handbook](https://i.ytimg.com/vi/3Wg1mRPRg0c/maxresdefault.jpg)
The Cosmic Revolutionary's Handbook
Great chat this morning with Dr Brian Keating on our recent book.
![Black Holes and the Mystery of the Ergosphere](https://static.wixstatic.com/media/4c8c3d_aedb9ffdb0c4495ea7e5ec7312cf68f4~mv2.png/v1/fill/w_454,h_341,fp_0.50_0.50,q_95,enc_auto/4c8c3d_aedb9ffdb0c4495ea7e5ec7312cf68f4~mv2.webp)
Black Holes and the Mystery of the Ergosphere
A new chat with Dr Karl, talking about black holes, spin, and the mysterious ergosphere (which is not a sphere!). Listen here
![](https://static.wixstatic.com/media/4c8c3d_814ee1718a74494f81cd15342ca6e2d5~mv2.jpg/v1/fill/w_250,h_250,fp_0.50_0.50,q_30,blur_30,enc_auto/4c8c3d_814ee1718a74494f81cd15342ca6e2d5~mv2.webp)
![Should academia be like Logan's Run? All out at 40?](https://static.wixstatic.com/media/4c8c3d_814ee1718a74494f81cd15342ca6e2d5~mv2.jpg/v1/fill/w_454,h_296,fp_0.50_0.50,q_90,enc_auto/4c8c3d_814ee1718a74494f81cd15342ca6e2d5~mv2.webp)
Should academia be like Logan's Run? All out at 40?
Time to rebirth a bit of blogging. It's been a while, but I recently saw an article about how old professors are blocking the career...
![](https://i.ytimg.com/vi/NlUxNfBDsbI/maxresdefault.jpg)
![A Theory of Music](https://i.ytimg.com/vi/NlUxNfBDsbI/maxresdefault.jpg)
A Theory of Music
In our latest video, Luke teaches me a theory of music. This is challenging, as I am tone deaf at the best of times. But you have to live...
![Vice Chancellor's Award for Outstanding Research](https://static.wixstatic.com/media/4c8c3d_02fd3f342f274fe4a64dc628a0f790b6~mv2.png/v1/fill/w_454,h_341,fp_0.50_0.50,q_95,enc_auto/4c8c3d_02fd3f342f274fe4a64dc628a0f790b6~mv2.webp)
Vice Chancellor's Award for Outstanding Research
Speaks for itself :) Very pleased to be recognised by my colleagues and the university.
![](https://i.ytimg.com/vi/0Q1fr7oxZ-Y/maxresdefault.jpg)
![Dark Matter, Expanding Space, and More](https://i.ytimg.com/vi/0Q1fr7oxZ-Y/maxresdefault.jpg)
Dark Matter, Expanding Space, and More
A new video from Alas Lewis and Barnes, answering viewer questions. If you have a question you would like us to tackle, let me know!
![](https://i.ytimg.com/vi/G-TD3gVM1GY/maxresdefault.jpg)
![The Dark Side of Galaxies: They're cannibals](https://i.ytimg.com/vi/G-TD3gVM1GY/maxresdefault.jpg)
The Dark Side of Galaxies: They're cannibals
I recently spoke to The Young Stars, a STEM program that reaches smart young minds around the worlds. Check out the video and Q&A session.
![](https://i.ytimg.com/vi/pTn6Ewhb27k/maxresdefault.jpg)
![The One-Way Speed of Light](https://i.ytimg.com/vi/pTn6Ewhb27k/maxresdefault.jpg)
The One-Way Speed of Light
How fast does light travel? Well, you might say the speed of light, but physicists have only ever measured the two-way speed of light,...
![](https://static.wixstatic.com/media/4c8c3d_00a208a140b74c3ab47e1cce41e94b01~mv2.jpg/v1/fill/w_250,h_250,fp_0.50_0.50,q_30,blur_30,enc_auto/4c8c3d_00a208a140b74c3ab47e1cce41e94b01~mv2.webp)
![The 2020 Nobel Prizes in Physics with Dr Karl](https://static.wixstatic.com/media/4c8c3d_00a208a140b74c3ab47e1cce41e94b01~mv2.jpg/v1/fill/w_454,h_341,fp_0.50_0.50,q_90,enc_auto/4c8c3d_00a208a140b74c3ab47e1cce41e94b01~mv2.webp)
The 2020 Nobel Prizes in Physics with Dr Karl
In my latest chat with Dr Karl, we discussed the 2020 Nobel Prizes in Physics - just what was the prize for? Learn about complex...
![](https://i.ytimg.com/vi/9DrBQg_n2Uo/maxresdefault.jpg)
![Do you expand with the Universe?](https://i.ytimg.com/vi/9DrBQg_n2Uo/maxresdefault.jpg)
Do you expand with the Universe?
I chatted with Derek Muller at Veritasium about this very question, and he made this cool video. Check it out.
![](https://i.ytimg.com/vi/ljoeOLuX6Z4/maxresdefault.jpg)
![The Supernova that Measured the Universe](https://i.ytimg.com/vi/ljoeOLuX6Z4/maxresdefault.jpg)
The Supernova that Measured the Universe
I spoke with Derek Muller about how you can use gravitational lensing time delays to measure the expansion of the universe. As usual,...
![](https://static.wixstatic.com/media/4c8c3d_297273593edc47688a66303175ee7604~mv2.jpg/v1/fill/w_250,h_250,fp_0.50_0.50,q_30,blur_30,enc_auto/4c8c3d_297273593edc47688a66303175ee7604~mv2.webp)
![Do we live in a simulation?](https://static.wixstatic.com/media/4c8c3d_297273593edc47688a66303175ee7604~mv2.jpg/v1/fill/w_454,h_341,fp_0.50_0.50,q_90,enc_auto/4c8c3d_297273593edc47688a66303175ee7604~mv2.webp)
Do we live in a simulation?
In my latest chat with Dr Karl, we ponder the question of whether we live in a simulation. This might sound strange, but some scientists...
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