Ptolemy's Theorem

The latest Numberphile video is a beautiful proof of Ptolemy’s Theorem, presented by Zvezdelina Stankova.

Zvezda’s proof was followed by a second video, which utilises Ptolemy’s Theorem to show two remarkable things about equilateral triangles and pentagons - well worth a look and a much shorter video.

There is a third video, posted to the Numberphile2 extra channel, which shows a little bit more about the method of inversion.

PS: The first video’s length and “epic-ness” is perhaps matched only by our “Epic CIrcles” from 2014, which funnily enough also heavily featured the use of inversion. That video was presented by Simon Pampena.

The Mummy Returns

A little while back we made an Objectivity video about a mummy called Tahemaa, which is being conserved at the Bournemouth Natural Science Society & Museum.

Well Tahemaa is back - and this time we got to open the coffin.

Like many people, I’ve had a lifelong fascination with Egyptology and the notion of discovering ancient tombs and mummies.

Making this kind of video is likely as close as I’ll ever get.

Thanks to the society and conservator Bethany Palumbo for making it possible.

You can help the society with the Tahemaa preservation project at this link.

If you’d like to see more Objectivity videos like this, you can help us get out and about by supporting Objectivity on Patreon.

Here is the first video we made:

China Trip

Some pictures from my China trip to accompany discussion on Hello Internet.

#TeamTrees

Today starts a big fundraising campaign to plant 20 million trees.

Various YouTubers and other “web people” are posting material related to the campaign.

FIND OUT MORE (AND CONTRIBUTE) HERE

I’ve posted this Numberphile with Tony Padilla, which combines two epic numbers we’ve discussed previously - TREE(3) and Graham’s Number.

We’ve combined them to create TREE(Graham’s Number).

The brown papers from this video are being auctioned for #TeamTrees.

For extra footage from the TREE(g64) video, see here.

For even more tree-related comment, see our Guide to Trees playlist created with Markus Eichhorn.

And here’s a video with Smarter Every Day about Moon Trees.

Fossil Videos

I hear it’s National Fossil Day!

Here are some Objectivity videos that are fit for purpose.

Turing on the £50 note

The Bank of England has announced Alan Turing will be on the next £50 note.

Here are some videos we’ve made on the topic…

First an Objectivity video in which we speculated about who might be on the note.

On the Numberphile Podcast I spoke with Simon Singh about his role on the committee which made the decision. It’s the early part of the podcast.

Here’s are some Numberphile videos about the Enigma Machine from Alan Turing superfan James Grime.

And some Computerphile videos…

Plus, while we’re speaking of the Bank of England, some gold in their vault…

Moon Rocks

Four years ago I visited Johnson Space Center in Houston.

Original Mission Control

The cool people at NASA (and my mate Destin from Smarter Every Day) arranged the visit and we went to my equivalent of a Holy Place — the vault in which the Apollo moon rocks are stored.

Among the collection was a cabinet full of the Apollo 11 rocks from Neil Armstrong and Buzz Aldrin’s famous first moonwalk.

Apollo 11 rock collection

We also saw The Genesis Rock - a famous sample collected during Apollo 15.

Genesis Rock on the Moon

Checking out the Genesis Rock

It has taken a while, but the video from that visit is finally published on Objectivity.

Destin did his own video too, of course.

And Joe Hanson from It’s Okay To Be Smart also visited and released his video in conjunction with ours.

For an Apollo fan like me this was an amazing experience.

My thanks to Destin, the lab staff at NASA, and our friend Gordon who also helped make this possible.

With Destin in Houston

Click here for more space-related videos on Objectivity.

Including this one with Public Service Broadcasting.

Cheeky pic of Moonwatch in Moon Rock room!