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Comment: Re:The Real Lie - faking statistics (Score 1) 380

by radtea (#49144137) Attached to: Lawmakers Seek Information On Funding For Climate Change Critics

Dyson is a physicist and mathematician, so his opinion on this matters exactly the same as yours - not a jot

So will you take my word as a computational physicist that climate models--which are nothing but computational physics done by climate scientists rather than computational physicists--are far too uncertain to be robust guides to public policy?

Because that is my professional opinion, and it happens that my profession is the one that matters when judging computational physics, whether it's done by climate scientists, Freeman Dyson, or anyone else.

I've read climate modelling papers. I've looked at climate modelling codes and there documentation (mostly AR4, which is somewhat out of date now.) I was appalled by what I saw: it's all a good attempt to work things out, there's nothing wrong with it as science at all, but I'd rather use Wall Street financial models to guide public spending policy than climate models to guide climate policy. They have a much greater chance of being accurate.

This is not to say that climate models aren't useful inputs to the policy debate, but their accuracy if fantastically over-estimated by policymakers. GCMs have gotten Arctic warming badly wrong (the Arctic has warmed much faster than anyone anticipated) and missed the current--likely temporary--flattening of "global average temperature" increase. This is no surprise you a) look at the models and b) have the professional competency of a computational physicist to judge them. They just don't do the things that accurate models integrated over long timescales have to do, like conserve mass and energy natively.

Models before around 2005 were especially bad with energy conservation, fixing it up by redistributing energy across cells after each time step. Climate scientists were apparently OK with that, because they didn't know enough computational physics. Anyone who has spent a career building models that eventually get checked against reality knows that that is a virtual guarantee that the result will be unphysical nonsense. This is not a political statement: it is simply a fact.

So by all means dis Dyson for not being a climate scientist. But since GCMs are computational physics, you must take my word as a computational physicist over climate scientists, or admit you really don't care who is saying what so long as they say what you agree with.

Comment: Re:Let it try at 80s/90s games (Score 1) 148

by weilawei (#49136931) Attached to: Artificial Intelligence Bests Humans At Classic Arcade Games

import random
import urllib.request

player = random.choice(['You', 'I'])
station = str()

tube_stations = urllib.request.urlopen(r'').readlines()
tube_stations = [i.decode('utf-8').split(',')[0] for i in tube_stations]

while True:
        if 'You' == player:
                station = input('Enter a station: ')
                station = random.choice(tube_stations)

        if 'Mornington Crescent' == station:
                print("%s won!" % player)
        elif station in tube_stations:
                print("%s chose %s. Wrong!" % (player, station))
                player = 'I' if ('You' == player) else 'You'
                print('Try a real station!')

Ask and ye shall receive?

Comment: Re:OMNI (Score 1) 121

by weilawei (#49094123) Attached to: The Science of a Bottomless Pit

How about a vacuum tube that was formed in a loop passing through Earth and then back around the outside? It would need to be around 8000 miles in diameter (as a circle), since Wolfram Alpha says Earth's radius is 3957 miles. The tunnel would have a circumference somewhat over 25,000 miles.

The engineering is left as an exercise to the reader.

Comment: Re:Technology can NOT eliminate work. (Score 4, Insightful) 389

by radtea (#49074097) Attached to: What To Do After Robots Take Your Job

This could be a cause for celebration, it's what mankind has always wanted, but here we are with people like you, who can't let go of the 40 hours work week, and you're pushing people into poverty because of it.

There are different ways of stating the problem.

1) "Technology is eliminating jobs! How will we cope with the unemployment?"

2) "Technology is increasing productivity! How will we distribute the gains?"

3) "Technology is reducing total workforce requirements! How will we reduce the work week?"

Each of these assumes a different fixed aspect of the economy. The first assumes that industrial capitalism will chug on, basically unchanged, while unemployment rises to unprecedented levels. History suggests this is unlikely.

The second assumes that productivity gains will continue without the incentive of paid work.

The third assumes that paid work will remain the only way of distributing productivity gains.

The rise of industrial capitalism saw enormous social upheaval. It is likely that the rise of total automation will produce something similar. We have no idea what that will be (I certainly don't) but it's important that we recognize that while not everything will change, everything could, and not confine our imaginary futures too narrowly. We're going to be wrong regardless (because our imaginations are terrible tools for knowing reality) but in this case we're more likely to fail by being too narrow in our view than too broad.

Comment: Re:Its politics/emotions not intelligence level .. (Score 1) 580

by radtea (#49043869) Attached to: Low Vaccination Rates At Silicon Valley Daycare Facilities

Science denial is probably more strongly correlated with politics/emotions not intelligence level.

One common thread in science denial is post-modernism. The American Right is dominated by post-modernists at the moment, and the Left has been for decades.

By "post-modernists" I mean people who believe that objectivity is not just impossible but actually pernicious, that truth is a social construct, and that "different ways of knowing" are equally legitimate and culturally dependent.

This is in contrast to the scientific mindset that understands that while there is no view from nowhere there is also no view of nowhere, and works hard to see that place that exists independently of the knowing subject as clearly as possible. Pro-science people are Bayesians, so they know certainty is impossible (knowledge is uncertain; faith is certain, and also an epistemic error) and that Bayes' rule provides the only consistent way of updating our beliefs in the face of new evidence, so it doesn't matter what your ancestors or you pastor tells you, there is only one way of knowing.

I'd bet a lot of these "highly educated" anti-vaxxers are victims of post-modernism in this sense. It should be relatively easy to find out how well they know their Derrida, Laccan, Leotard and Foucoult compared to their more vaccination-friendly neighbours.

Comment: Why not fantasize about finding a winning ticket? (Score 1) 480

by radtea (#49034557) Attached to: The Mathematical Case For Buying a Powerball Ticket

The odds aren't appreciably closer to zero, the enjoyment is the same or greater, there is no chance of disappointment, and the cost is zero.

If you invest the $104 a year you'd otherwise spend on lottery tickets then with interest at the end of 40 years (from age 20 to age 60) you will have accumulated about $9K, assuming 3.5% interest.

Comment: Re:the winter dragon is coming, (Score 1) 54

by weilawei (#49031883) Attached to: Something Resembling 'The Wheel of Time' Aired Last Night On FXX

Yep, that was a fantastic shooter. Nothing out at the time (that I know of/played; someone will correct me here) really had interacting weapons like that. Turned it into a very fast-paced version of chess, plus you could lay traps in your area before a match started.

Computer Science is merely the post-Turing decline in formal systems theory.