### Ashley Yakeley

Shared publicly -Why do galaxies all have that same symmetry (I think it's 2/m) and no other?

1

Add a comment...

Start a hangout

Ashley Yakeley

105,823 views

AboutPosts

Why do galaxies all have that same symmetry (I think it's 2/m) and no other?

1

Add a comment...

Am I doing the right thing, exercising the rights the authors gave me, or depriving them of fair compensation?

https://www.reddit.com/r/opensource/comments/3kfcn6/forking_to_enable_subscriberonly_features_in_emby/

https://www.reddit.com/r/opensource/comments/3kfcn6/forking_to_enable_subscriberonly_features_in_emby/

2

Add a comment...

Are we living in a simulation? I don't mean the brain-in-a-jar (or body-in-a-pod) kind of simulation shown in The Matrix. I mean, is our whole universe, including our brains and minds, being simula...

1

4 comments

This kinda reminds me of the fact that pretty much any file can be losslessly compressed to 1 bit, as long as you allow for a suitably special purpose decompression program.

Add a comment...

On Univalent Foundations, with some reference to proof assistants.

https://www.quantamagazine.org/20150519-will-computers-redefine-the-roots-of-math/

https://www.quantamagazine.org/20150519-will-computers-redefine-the-roots-of-math/

3

1

Ashley Yakeley

+

1

2

1

2

1

I've been trying to formalise mathematics in Coq as a way of learning it rigorously, but it's been tough going.

https://github.com/AshleyYakeley/maths

https://github.com/AshleyYakeley/maths

Add a comment...

I have a special fondness for the Monoid and Applicative classes. Sometimes if you're wrestling with a type, trying to write it to best capture the semantics, if you can somehow make it an Applicative, with all the laws correct, everything else will magically fall into place.

The same thing often applies to Monoid (for kind * of course), though to a somewhat lesser degree.

The same thing often applies to Monoid (for kind * of course), though to a somewhat lesser degree.

3

Add a comment...

Hey mathematicians & statisticians (+John Baez +Dan Piponi +John Cook etc.)

From the outside, the field of statistics seems remarkably disorganised, like it’s a big grab-bag of tests and statistics for various situations. It seems like the kind of thing that in other mathematical fields would be sorted out by category theory and the like, but this seems not to have happened. I would have expected something like a general language of hypotheses or something.

What’s up with that? Am I way off-base here?

From the outside, the field of statistics seems remarkably disorganised, like it’s a big grab-bag of tests and statistics for various situations. It seems like the kind of thing that in other mathematical fields would be sorted out by category theory and the like, but this seems not to have happened. I would have expected something like a general language of hypotheses or something.

What’s up with that? Am I way off-base here?

4

2 comments

John Cook

+

3

4

3

4

3

Statistics is messy because it is outwardly focused. The development of number theory is shaped by the questions number theorists ask themselves. But statistics is shaped by the questions asked by doctors, bureaucrats, electrical engineers, marketers, manufacturers, ... Different domains have different kinds of data and different objectives. Sometimes the requirements of a problem domain are mathematically awkward but cannot be avoided.

That said, Bayesian statistics is much better organized than frequentist statistics. All Bayesian inference takes the same form, and for that reason some people refer to "turning the Bayesian crank." Bayesian statistics is messy too at the application level, but at a fundamental level it is well organized.

That said, Bayesian statistics is much better organized than frequentist statistics. All Bayesian inference takes the same form, and for that reason some people refer to "turning the Bayesian crank." Bayesian statistics is messy too at the application level, but at a fundamental level it is well organized.

Add a comment...

A great deal of my coding work takes the form of two steps:

1. restructure the code without changing the behaviour

2. make a small change to the code to make the desired behavioural change

1. restructure the code without changing the behaviour

2. make a small change to the code to make the desired behavioural change

8

1

Add a comment...

Co-worker's license plate is WHUMSUM (for "what happens under the monad stays under the monad"). #Haskell

9

I assume that's the same colleague who sometimes has that quote in his email signature? Didn't know about the license plate.

Add a comment...

"Ah, I see you've come to have your mind uploaded into cyberspace. Well come in. Think of a number and don't tell me what it is." "Um, OK." "Jolly good. Now lie down on that table with the scanning...

3

1

17 comments

Dan Piponi

+

1

2

1

2

1

> They wouldn't get to travel anywhere

That claim only makes sense for the tiny minority of people living on the backwater called Earth and who speak certain ancient dialects. For the rest of the galaxy there is no word that means "travel except via beaming" and most of the Galaxy would find such a word about as useful as a word that meant "two, except when counting apples".

That claim only makes sense for the tiny minority of people living on the backwater called Earth and who speak certain ancient dialects. For the rest of the galaxy there is no word that means "travel except via beaming" and most of the Galaxy would find such a word about as useful as a word that meant "two, except when counting apples".

Add a comment...

One of the problems of not being trained in mathematics is that even when I have a rigorous proof in my head, I have trouble writing it down in a way that mathematicians can read without scratching their heads.

I've been learning Coq, but that may be possibly worse in this regard.

I've been learning Coq, but that may be possibly worse in this regard.

3

4 comments

Having worked with another proof tool, PVS, I simply gave up. The tool insisted on introducing type constraints at the strangest corners of proofs, so I ended up just being led by the tool.

Probably was a lousy formalization I was working in anyway. Should have terminated my work on it earlier.

Probably was a lousy formalization I was working in anyway. Should have terminated my work on it earlier.

Add a comment...

Having a big argument with Coq. These arguments tend to end the same way, with me suddenly realising where I'm wrong. It's like arguing with God in the Jewish tradition.

(In this case, I told Coq that a**Lattice** is a **PartialOrder** with some stuff, and a **BoundedPartialOrder** is also a **PartialOrder** with some stuff, and a **BoundedLattice** is a **Lattice** and a **BoundedPartialOrder**, but Coq won't let me do anything useful with **BoundedLattice** because I haven't shown it that the two implied **PartialOrder** instances are the same.)

#Coq #DiamondOfDeath

(In this case, I told Coq that a

#Coq #DiamondOfDeath

3

1

Add a comment...

Communities

5 communities

Links

YouTube

Contributor to

- Immanence (current)

Story

Tagline

Bloody Brilliant.

Apps with Google+ Sign-in

- The Room Two