Session Expired

I wouldn’t be at all suprised if Labour doesn’t reorientate itself to be “left wing Reform” over the next year.

“Get In” by Patrick Maguire is really interesting about Starmer’s political philosophy, or lack of! As Tony Benn said, there are two types of politicians: signposts and weather vanes. KS seems to definitely be the latter.

Hugs and support to all my trans and non-binary friends. Let’s hope the law is clarified now.

Regex is a bit old school. They’re probably developing a DL model to assess informational content!

So what’s with that terrible OneDrive iOS app they published last night? Not so much buggy as totally useless. But new UI so that’s ok. Did they let an intern publish an alpha by mistake?

When something like this happens you can hear the cogs whirring as the acolytes try and rationalise it. Silence for a few hours, then “oh it’s his condition” or “it’s a Roman salute”. We all know exactly what it was.

I really enjoyed this one. Fun and informative!

If you accelerate half way and decelerate the second half the journey would take longer, about 63 years. Still within a human life time, but what would you find at the other end after 100 trillion years have passed? 👽How much will the universe have changed ☄️ 3/3

Time dilation on this journey is so extreme, a year on Earth would pass in just 300 nanoseconds on the ship. Length contraction is so extreme that a galaxy would shrink from 100,000 light years deep to about 9,000km (peak Lorentz factor 103,229,527,555,360) 2/3

Let’s do a tour of the universe 🛸How far can we travel in a human lifetime, accelerating at 1g? A very long way! Over 100 TRILLION light years in less than 32 years, it turns out. That’s much larger than the current size of the universe (although it will expand during our journey).. 1/3

When asked to describe the plot of Inland Empire, David Lynch paused and replied “It’s about… a woman in trouble”.

Ah GR is well above my pay grade at the moment!

Bonus: relativity states the laws of physics are the same in all inertial frames. Objects don’t magically gain mass just because they’re moving quickly from someone’s perspective.

In conclusion ‘relativistic mass’ is misleading and varies by reference frame chosen. An object has 10 different apparent masses simultaneously in 10 different frames. For the ship, constant proper acceleration at 0.99c is no harder than 1g at 0.01c. Let’s go! 🛸 5/5

So its Lorentz factor is just 1, its relativistic mass is just the same as ever! It’s no harder to move than it was when it was stationary, because from its own frame it IS stationary. So relativistic mass isn’t an issue, it can keep up the same proper accel with the same fuel use.. 4/5

So the apparent mass of a 1kg object travelling at 0.9999c is 1*70.71 or about 71kg, a big increase that makes it difficult to accelerate further. This will rise towards infinity as velocity increases. BUT from the object’s own frame of reference (eg a ship’s engines) it isn’t moving.. 3/5

This gets gradually more difficult as the relativistic mass of the protons gets larger. Relativistic mass is a concept physicists don’t like because it’s misleading, but it’s calculated from rest mass * Lorentz factor, and the Lorentz factor depends on *relative* motion.. 2/5

Do objects get harder to accelerate as they get closer to the speed of light? Yes and no. They get harder to accelerate from an outside frame of reference, like the protons in a particle accelerator. This is because the accelerator is static and it’s pushing the protons closer and closer to c. 1/5

The science passes every test they have tried en.wikipedia.org/wiki/Tests_o...

Andromeda and back at 1g would be around 57 years on the ship, but it would be 5 million years later when you arrived home! 🚀

Yes it would still be millions of years later on Earth. The journey in subjective time (physicists call it “proper time”) would be longer because you’re stopping half way.

Ps. MpMath was really invaluable for all the large numbers. I’m working on C# and Rust versions using similar arbitrary-sized floats, but the initial fixed-precision versions are also there as gists

Utilities for working with Special Relativity in Python. Arbitrary precision with MpMath but no units of measure or strong typing Utilities for working with Special Relativity in Python. Arbitrary precision with MpMath but no units of measure or strong typing - Relativity_lib.py

Sure, you can check my math! gist.github.com/lookbusy1344...

One of the best things about The Expanse is no ridiculous hurricane for 10 minutes when someone opens an airlock to space

Bonus: some people think ‘relativistic mass’ stops this proper acceleration in its tracks. But that’s wrong! See the next installment

So even though it takes millions of years *from the point of view of Earth* on board ship only 15 years pass because your destination actually gets closer. Accelerating hard enough you could get there in less than a day. But that would definitely squish you! 1g is nice and safe for humans. 5/5

At relativistic speeds space and time start to “smear out” into each other. Time slows down on board the ship, and the distance to your destination actually shrinks. This is described by the Lorentz factor and was worked out around 1905. It’s key to Special Relativity.. 4/5

With speed peaking at 99.99999999999249% light speed you can cross that vast distance in only 15 years, but how? It’s 2.5 MILLION ly right?! And you can’t go faster than light.. 3/5

Here’s the Python I used to work it out. 2 solutions are given, one for accelerating all the way, and one for Expanse style flip-and-burn at the half way point. This is more practical if you want to stop at your destination! 2/5

How long would it take to travel to the Andromeda galaxy 2.5 million light years away, accelerating at only 1g, Earth gravity? No warp drive, just classic Relativity from a century ago? Turns out you can do it in less than 15 years! The universe is smaller than you think at relativistic speeds 1/5