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JohnLBevanon What every programmer should know about time

Talking of the DST point, how do you manage this in your apps? Say we're in the UK, you schedule something to run at 9am GMT. In the summer, the timezone changes to BST, so 9am GMT is still 9am UTC. I've never seen a scheduling app where you say 9am UK, and have it automatically switch GMT to BST. The closest I've seen is "use server time" where you have to setup the server to automatically apply the DST rules - but then you have issues when working with out of sync DST rules, such as those of the US.

JohnLBevanon What every programmer should know about time

It's about time someone posted about this. Great summary - when I first started working on an international system I was hunting for this kind of article. Now if someone could only do one on languages, regional settings, character sets and encodings. . .

JohnLBevanon Is earth travelling at 0.88 speed of light

Hey Miahi, I agree with what you, but I think Ifran's question is about why the light had to travel so far in the first place.

If you assume(?) that the maximum speed anything can travel is the speed of light, and ignore factors such as space expanding (redshift / inflation) then at .77bn years the radius of the universe would be .77bn ly, so the maximum distance between two objects (A & B) is 1.54bn ly. Now if light leaves A it has to travel that 1.54bn ly to point B; it shouldn't take 12.9bn ly to do this. However, A and B aren't fixed points - so though the light from A is heading towards B, B is trying to run away (albeit at a slower pace). Here, Ifran's calculated the minimum average speed at which B would be running from A as .88c (if we assume that light from B is moving at c and not influenced by any interference, and that both A and B moved at c for the first .77bn years). That seems to be moving too fast, given at this stage in the universe's life the known/current laws of physics apply. Redshift can account for some of this, and Inflation means that the starting distance can also be much larger than the assumed 1.54bn ly, which hopefully explains the rest?

JohnLBevanon Is earth travelling at 0.88 speed of light

Hey Miahi, good point, but if the light set off at .77bn years, and we assume it's on the edge of the far side of the universe to us, we'd be at most 1.54bn light years apart (were it not for Inflation) when the light left. We'd be moving away from the light, but it's taken 12.9bn years to cover the initial 1.54bn light years and subsequently catch up with us. JB

JohnLBevanon Is earth travelling at 0.88 speed of light

It could be due to Inflation (http://en.wikipedia.org/wiki/Inflation_(cosmology)). This is where the universe expands faster than the speed of light, since it's not the matter moving, but the space between it that's expanding. Not my area though, so would welcome thoughts from someone intelligent in that area. JB

JohnLBevanon Ask HN: Could you build an entire web app in just one language?

There's also a language/tool called Monkey Coder which attempts something along these lines; though it's more aimed at creating apps for the different kind of platforms (iphone, android, html5, mac/pc/linux app, etc). I haven't played with it yet, so can't comment, but if you're interested, check it out here: http://www.monkeycoder.co.nz/