Programmers' Day

(Daniel Hollands) #1

Alas I missed it myself, not learning of it’s existence until yesterday, but did anyone here celebrate Programmer’s Day on Saturday?

What I love about this holiday is how it’s calculated. It isn’t based on the movements of the moon, or some ancient religion, but simply:

is celebrated on the 256th (hexadecimal 100th, or the 28th) day of each year (September 13 during common years and on September 12 in leap years).

This very much appeals to the geek in me :computer:

Calendar of events Project Idea
(Nick Goodall) #2

Damn, missed it! :frowning: Maybe next year…

(Tajinder Singh) #3

Didn’t know, next year defo then…

(Daniel Hollands) #4

DAMN IT!! Missed it again!! :anguished: TWICE :disappointed_relieved:

(Andy Wootton) #5

How did they (mis)calculate the start of the year? :smiley:

I’m not even convinced that our current understanding of time is on a sound scientific footing. I accept that it exists but not that it’s linear or ‘the fourth dimension’. Why would only one of the dimensions have a one-way sign on it?

(Marc Cooper) #6

The difficulty probably comes from misunderstanding the use of the word dimension. Relativity is described via the use of the metric tensor, which is a 4-dimensional differentiable manifold. Time isn’t equivalent to a spacial dimension in the tensor, as can easily be imagined by considering its functions and units (and is intuitively obvious, in any case).

However, if you want to describe functions that reverse time, there’s nothing in the mathematics that stops you from doing so. Observation (experiment) concludes that this isn’t necessary, so the science is definitely on a sound footing. If you have an experiment that shows something different, then a Nobel awaits :slight_smile:

(Andy Wootton) #7

I already know that I don’t understand this. I think I had about 5 lectures on special relativity, by a physicist who probably didn’t understand the maths either

I was recently told off by a mathematician for talking about negative entropy because there’s no such thing. I used negative time as my counter-argument. No-one is going to tell me that yesterday isn’t ‘today - 1 day’.

I very much accept that time is one-way but I’m unconvinced by the lack of evidence that it’s linear. I thought I was on shaky ground but I recently heard Prof. Brian Cox say that time is one of the least understood things in physics.
Learning about Clojure’s immutability, I played with the idea that time is a consequence of state change in the universe (or multiverse.) If you consider the multiverse as all things that might happen in the future of this universe, rather than that all things do happen in multiple universes, then the present is a wave of ‘decisions’, wiping out future possibilities. Even if it isn’t true, it fits nicely with Agile theory: make decisions as late as possible to keep more of the future alive.

(Marc Cooper) #8

Henry Reich (@minutephysics) and Sean Carroll got together to explain why time doesn’t flow backwards. Just for you @Woo!

(Andy Wootton) #9

Then there’s another theory that says Time reverses at the end of the universe and pulses infinitely.

I’d say that video is a description rather than an explanation. Time is caused by entropy increasing, like temperature? :smiley:

I found this today but I don’t understand enough relativity or quantum mechanics to read past the second paragraph.

(Marc Cooper) #10

So, this popped into my time:

Which reminded me of a video I’d seen years ago that nicely links to the time reversal theme and entropy:

It’s also a nice reminder of how our senses can misguide us.