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rjshadeon Time Travel Simulation Resolves “Grandfather Paradox”

"Perhaps! But this problem only comes up if you're not the centre of the Universe."

http://www.qwantz.com/index.php?comic=1394

rjshadeon QUIC – Next-generation multiplex transport over UDP

wmf is right in saying this is early days and we're still experimenting.

However there is a roughly up to date wire spec here: https://docs.google.com/a/google.com/document/d/1WJvyZflAO2p...

and a much more detailed design doc here: https://docs.google.com/document/d/1RNHkx_VvKWyWg6Lr8SZ-saqs...

rjshadeon QUIC – Next-generation multiplex transport over UDP

QUIC is in the Chromium source:

https://code.google.com/p/chromium/codesearch#chromium/src/n...

and there's a demo server here:

https://code.google.com/p/chromium/codesearch#chromium/src/n...

rjshadeon QUIC – Next-generation multiplex transport over UDP

> And how will Chrome know whether to try to connect via QUIC or not?

Chrome looks for the "alternate-protocol:443:quic" response header (in non-QUIC requests). Once it sees this it will attempt to talk QUIC in future requests to the same domain.

And thanks for pointing out the omission of chrome://flags/#enable-quic in the slides. Have fixed this.

rjshadeon One meteorologist explains why he won’t fly again

There's an interesting response to this, in which the author argues that "for the sake of the planet, please fly!":

http://qz.com/131024/its-ok-to-have-a-big-carbon-footprint-a...

rjshadeon $165 Billion: Food Thrown Away By Americans Every Year

Americans wasting/not wasting some of their surplus food (in America!) is not going to affect starving people elsewhere

The money used to buy (and then waste) surplus food could be donated to the most effective charities[1][2], thereby saving lives. You could donate directly to charities which feed starving people although these may not do the most good (in terms of lives saved per dollar donated).

[1]http://www.givewell.org/ [2]http://www.givingwhatwecan.org/resources/charity-comparisons...

rjshadeon Andreessen Horowitz to give half their earnings to charity

Oh and this is similar to the approach that the Gates foundation is taking. As far as I can tell Gates approached this as an optimisation problem: given that he has X billion dollars to give to charity, how can he maximise the effect that his donations have? How many lives can he save* with that money?

* lives saved is of course the wrong metric: no-one has ever saved a live, just prolonged it, but it's a convenient shorthand for maximising the number of quality adjusted life years (QALYs)[1] that a donation could buy.

[1] http://en.wikipedia.org/wiki/Quality-adjusted_life_year

rjshadeon Andreessen Horowitz to give half their earnings to charity

This is great. Something people often disregard, but which is hugely important, is charity effectiveness. This boils down to measuring the impact that you can make with a given donation: it turns out some charities are literally thousands of times more effective than others.

A lot of people don't realise how much good they can do with modest donations to the right charities -- until a year ago I really had no idea myself. There are a couple of groups which I know of which do analysis of charity effectiveness:

* Giving What We Can (http://www.givingwhatwecan.org/) are an Oxford, UK based organisation who estimate that you can save a life for ~£300.

* GiveWell (http://givewell.org/) are a US group who do similar research

They both publish lists of the most effective charities they've researched, and Giving What We Can have a calculator which shows you how much you can achieve by donating 10% of your income each year:

http://www.givingwhatwecan.org/resources/what-you-can-achiev...

I think these stats are astonishing and it's really changed my approach to charity. Worth checking out if you're interested at all in philanthropy!

rjshadeon Don't Store Passwords, Generate Them When Needed

My solution is to use Keepass. It stores passwords in an encrypted database file which I store in Dropbox - that solves the machine synchronization problem.

The main database is protected by a passphrase and/or keyfile (any file which won't change e.g. ~/Dropbox/Photos/2008/France/Photo5.jpg). One advantage of this is that a simple keylogger will be stumped by the keyfile - even if your passphrase is recorded an attacker still needs Photo5.jpg to decrypt the database.

It's originally a Windows app (http://www.keepass.info/), but is open-source and there's a fully featured Linux/OSX port called KeepassX (http://www.keepassx.org/)

rjshadeon Before I Die...

You could spend all days coming up with possible reasons for not defrosting cryonics patients in the future. However you need to remember that no matter how low a probability you assign to your successful defrosting, this will be strictly greater than the probability of successfully being alive in the future if you go with the default, non-cryonics option of irrevocable destruction.

rjshadeon Root molecular cause of declining health in the old found by scientists

Higher order life has this "defect" because, from an evolutionary perspective, there is little reason for us to stick around for very long after reproducing. After passing our genes on to our children we have some years where it is helpful for their survival that we are still alive, but pretty soon Darwin has no more use for you.

The various problems that you imagine might result from curing ageing can be solved _after_ we solve the problem of hundreds of thousands of people dying every single day.

rjshadeon Which supplements really work? An interactive guide to evidence.

Previous discussion: http://news.ycombinator.com/item?id=1150604

rjshadeon XKCD Explained, One Strip at a Time

A second valid response would be to correctly attribute the quote to E.B. White: http://en.wikiquote.org/wiki/E._B._White

rjshadeon Learning to juggle grows brain networks for good

I've been juggling for a few years now and find it both useful for zoning out and thinking about tough problems, and intrinsically satisfying - it's a great feeling to nail a new trick for the first time.

For anyone interested in learning I found this video site extremely helpful:

http://homepage.mac.com/abramr/juggling/tutorial/category/in...

Takes you from complete beginner to covering loads of 3 ball tricks, and onto 4 and 5 ball if you are so inclined. Has side by side full speed and slow motion videos.

The mathematical structure behind juggling patterns is quite interesting - various notations have been developed including siteswap:

http://en.wikipedia.org/wiki/Siteswap

rjshadeon Conway's Game of Life implemented in Brainfuck

Here is an example of a GoL unit cell - "a pattern with two states, which is determined by its previous state and the previous state of its neighbors, using exactly the rules used to compute it; that is, it simulates its own universe": http://www.radicaleye.com/lifepage/patterns/unitcell/ucdesc....

Basically a pattern in GoL that mimics the behaviour of a single cell. A regular grid of these would therefore implement Conway's Game of Life in Conway's Game of Life (and of course you could do this recursively to any level you choose - at an exponential decrease in speed of course)