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Comment: Lost grant funding? (Score 1) 171

by Roger W Moore (#49157067) Attached to: One Astronomer's Quest To Reinstate Pluto As a Planet

Why does the concept of another category, dwarfs, enrage people?

I don't think it does but for the definition to work it will have to have some sort of sensible criteria to separate them from asteroids. However clearly the notion that Pluto is not a planet really upsets a lot of people which is something I find hard to understand. Does it really matter that much how we classify it? Indeed it seems such a silly, unimportant thing to be arguing over again when there is real science to be done that it makes me wonder if the astronomers involved have lost their grant funding and so have nothing better to do with their research time.

Comment: Computer Cost and Support? (Score 1) 28

not everyone has the money to pay the teachers. Nor are there enough people educated to be teachers.

True enough but in that case how are they going to have the money to buy computers and have people educated enough to be able to support them and keep them running? Not to mention the electrical power to run them let alone a network connection. It seems to me that if they have what they need to purchase and keep running all these computers they probably have what they need to teach basic literacy and arithmetic without computers.

Comment: Very Unlikely (Score 4, Interesting) 202

by Roger W Moore (#49126789) Attached to: What Happens When Betelgeuse Explodes?

I look at the sky every night, knowing the light is hundreds of years old. Half of the stars might have gone supernova already.

The life cycle of even the largest stars is still in the 10-100 million year range. The chance that one of them has exploded in the last few hundred years is tiny. Galaxy-wide we expect one supernova roughly every century so, unless you get really lucky, practically every star you can see with the naked eye has an extremely good chance of still being there...even Betelgeuse which they estimate has a 100k year lifespan remaining and is only 600 light years away. Of course if you had RTFA you would have known most of this...hope you appreciate the irony!

Comment: Re: Understanding Essential (Score 1) 672

by Roger W Moore (#49122985) Attached to: Bill Nye Disses "Regular" Software Writers' Science Knowledge
Firstly I don't think you read my post correctly. Secondly while that may be true for us physicists I doubt the average biologist can explain from first principles how GPS works and the corrections that are needed (since this involves GR) but I bet they have a very good idea about its position accuracy. You need to know how the apparatus works and performs but that does not mean that you need to know every detail from the level of fundamental physics and upwards.

Comment: the Summer (Score 1) 284

by Roger W Moore (#49122473) Attached to: I ride a bike ...

I don't go fast enough to need to change clothes when I arrive

It's usually cold enough and dry enough that I don't need to change clothes when I cycle in to work. On the downside though you really cannot cycle in the winter - the river valley park I cycle through has ~0.5m of snow which they don't plough and the temperatures can hit -40C which is a bit nippy for cycling (although so do do it!).

On the plus side the summer is warm (20-25C) and low humidity usually which is ideal cycling weather and there is far less rain than a British summer - even those in East Anglia. Not sure about the "free" part though - bikes take money to buy and upkeep. One of the strange things I've notices switching from a wet UK climate to a dry central Albertan one is that chains wear out quickly. I cycled for 6-7 years as an undergrad/grad student without needing to replace a chain but here I had to replace it after less than 3 years.

Comment: Honest about it (Score 1) 672

by Roger W Moore (#49109491) Attached to: Bill Nye Disses "Regular" Software Writers' Science Knowledge

He argues about climate denial, and resorts to insults attempting to make the point. Antagonizing people is probably the worst method of teaching them.

Yes but he is at least honest about that: he is one of America's foremost science educators and he grades America's science education as an 'F' so exactly how good a teacher did you think he was going to be?

Comment: Understanding Essential (Score 3, Informative) 672

by Roger W Moore (#49109417) Attached to: Bill Nye Disses "Regular" Software Writers' Science Knowledge

An astronomer might know a little about the optics inside his/her telescope, but the level of understanding that a physicist would have is simply not in scope.

Actually I would expect an astronomer to have a level of understanding of the optics in their telescope comparable to that of a physicist's understanding of their own experimental apparatus. If you don't understand the apparatus you use to collect the data then that data is useless because you won't know whether some interesting feature of the data is due to some new phenomena never before observed or because you forgot to plug in your GPS cable properly.

Comment: Re:From Mall of America visitor rules: (Score 1) 241

Maybe, it's more than just laws about how easy or hard it is to get a firearm?

Undoubtedly it is - historically neither the US nor Europe had strict gun control laws and neither appeared to need them. However given that both now have a problem with violence in society it is undoubtedly the case that gun control limits the damage of that violence. Having strict gun control laws in one region is useless: it is trivially easy to go outside that region, purchase what you want, and return with it with almost zero chance of being caught. It's like a "dry country": everyone there just drives a few kilometres to the county next door to purchase alcohol.

Restrictions on items only work when you implement them throughout a region where there is some border control e.g. at the national level. Once you have this there is a reasonable chance of being caught and/or the expense to avoid detection limits the number of criminal enterprises who can get around the law and so limits supply.

Comment: Re:From Mall of America visitor rules: (Score 4, Insightful) 241

How about removing that rule as a first step? 'Gun free zones' are instant targets.

You might possibly have had a point if we were considering an armed robbery of the mall, although the fact that countries with strict gun control laws have murder rates that are a tiny fraction of the US suggests that the downsides far, far outweigh any small benefit.

However I really don't understand how a civilian armed with a gun will stop a terrorist bomb. Having armed civilians wandering around a shopping mall shooting anyone with a backpack, bag or briefcase who looks "suspicious" frankly sounds like a far more terrifying prospect than a terrorist with a bomb and one likely to result in far more deaths. What we need is a plan to stop them from causing "terror", not one where you do it for them

Comment: EdSame approach as for the rest of life (Score 4, Insightful) 257

by Roger W Moore (#49105575) Attached to: Ask Slashdot: Parental Content Control For Free OSs?

Anyway I don't know why a parent should not be a good parent if he looks for extra means of protecting his children, other than what you can do every day.

What is being asked for is not a form of protection but a dangerous abdication of responsibility. Indeed we've known it is bad for so long that we actually have a fairytale we read to our children which cautions against it. Remember the tale of sleeping beauty who was to prick her finger on a spinning wheel before falling asleep and so the king banished all spinning wheels from the kingdom. Since it was impossible to completely enforce the blockade the result was that when she saw a spinning wheel she was so curious abut it she ended pricking her finger.

The same applies to the internet: you cannot block everything. Instead you can just use the same approach that you use for everything else in life: set out the rules, supervise them so you have a reasonable chance of noticing any serious violations (if your kids are human there will be violations and you will not catch all of them), make sure there are consequences for those serious violations you do catch and finally teach them how to deal with any inappropriate content which they do manage to see.

Nobody suggests that we should combine HHGTTG and Google Glass to make glasses for kids that will turn black and the first sign of anything deemed inappropriate occurring in real life. Indeed we set up rules for our kids to help avoid such situations and we make sure that our kids know how to handle such situations if they do occur (e.g. say no to strangers, don't do drugs etc.). So why don't we take the same approach to parenting with the internet?

Comment: Re:Actually 13/8 times the energy (Score 1) 89

by Roger W Moore (#49098721) Attached to: Scientists To Hunt For Supersymmetric Particle In LHC

The gluino plays a similar naturalness role as the stop, at 2-loop level.

Do you have a paper to back that up? It seems very surprising that a 2-loop level effect would have the same constraints as something at the tree level.

Just beyond the limits is not an arbitrary choice. Given our current limits already, naturalness points to these masses being as low as possible.

Not quite. Given our current understanding it would appear more natural to have SUSY at a lower mass scale but if we find SUSY at 10TeV all that means is that SUSY is perhaps less natural than it could have been. It's like tossing a coin: how many heads in a row do you need to get before you conclude that the coin is weighted? You can draw an arbitrary line in the sand and say '5 sigma' but it is just that an arbitrary line in the sand. With SUSY we have the same problem: you can put an arbitrary line on the energy scale and say "above X TeV it is unnatural" but it is just that: an arbitrary line. You might be happier if SUSY existed at a lower energy scale (I would be too!) but the universe is not there just to make us happy.

Comment: Re:Actually 13/8 times the energy (Score 1) 89

by Roger W Moore (#49085081) Attached to: Scientists To Hunt For Supersymmetric Particle In LHC

Therefore I prefer to look at it experimentally, i.e. wrt our current limits. If the gluino and stop are just beyond our current limits, then, according to my previous posts (which apparenntly completely missed the point...) the gluino will jump in our face

How is making an arbitrary choice that stop and gluino are both just beyond the current limits "looking at it experimentally"? What's to prevent stop being just beyond our detection range with the gluino being far above it? The argument for a light stop is that the top has a large correction to the Higgs mass due to its strong coupling: I'm not aware of any such argument for the gluon since it is massless. Natural SUSY does not place any hard limits on the upper bounds: things just get less natural as the masses increase but there is no line in the sand where the models cease to be natural. You could perhaps argue that it is unnatural by the time you get to ~10TeV or higher without SUSY but, as you say, it is purely subjective and not at all 'experimental'.

Neutrinos have bad breadth.