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Comment Fiscally impossible (Score 1) 164

Air travel should be something that you do when you're crossing an ocean, because trains over water (and subduction zones) are physically impractical

Actually it is fiscally impractical, not physically impractical. You could physically build a vacuum tube-based maglev train where the tube is at some depth in the ocean to avoid surface issues and plate boundary problems. However the costs when people look at these things are utterly insane...but in theory it is physically practical to build such a thing.

Comment Electrical Fuel Transmission (Score 1) 129

The bigger the vehicle + cargo the more fuel you need to lift PLUS you need more fuel to lift the extra fuel.

If using conventional fuel then you are right. However unlike physical fuel electrical power can be transmitted wirelessly. Of course the technical challenges to do this would be immense for a moving vehicle but it does present a possible option not available to traditionally fuelled vehicles. However given all the challenges with current technology I would agree with your conclusion that Uber is very unlikely to crack this but it remains an intriguing possibility that at some point someone else might.

Comment Re:Dishonest Arguments not Politics (Score 1) 605

Not very many creationists deny that creatures change from one generation to the next....so I think it's dishonest to portray creationists as though they have their eyes and ears covered and deny all of that.

That is actually far less rational though so my apologies for giving creationists too much credit. So what you are saying is that they believe evolution happens but that despite the fact that this evolution could explain the entire fossil record they reject that idea and believe that the world was created by someone with a heck of a sense of humour because they went to all the trouble to create fossils consistent with evolution? I have a hard time believing that anyone really believes this: it seems far more probable that this is a rationalization they use to let them support measures against diseases without having to publicly admit they are wrong.

Comment Re:Dishonest Arguments not Politics (Score 1) 605

the argument is only "overwhelming" when you ignore thousands of scientists who disagree

I don't know *any* scientist who disagrees with the fact that the planet is warming. Where the disagreement lies is in the degree of the warming that is being caused by human activity. What we need to have a is a sensible debate about how we can start to reduce greenhouse gas emissions while the science figures out how much we need to reduce it by.

Instead we have an inflammatory debate with one side refusing to admit there is any problem at all (despite the overwhelming evidence that the planet is warming) and the other side responding with equally non-scientific doomsday-like scenarios. The result is deadlock and inaction when instead we need to start taking sensible, measured actions now to avoid a situation where we need to take very significant, rapid actions which could cause huge economic upheaval.

Comment Dishonest Arguments not Politics (Score 5, Insightful) 605

Not really it is simply people making dishonest arguments. The scientific evidence that the planet is warming is overwhelming the problem is that the proposed solution - reducing greenhouse gas emissions - carries with it a huge economic impact. Not surprisingly this means there are a large number of people who believe that the economic problems from reducing greenhouse gas emissions outweighs the problems of just warming the planet.

However they believe that this argument is not strong enough to prevent everyone deciding to cut greenhouse gas emissions so, although they really believe the science, their only option to prevent the economic problems they are worried about is to attack the science and try to pretend that it is wrong. So really this is simply a dishonest argument made be people who are so afraid of the impact of curbing greenhouse gases that they attack the arguments for this in the only way that has any chance of success even though they don't really believe the argument they are making themselves

When the chips are down so to speak it is amazing how overwhelmingly people will back science. One of the best examples of this which is often pointed out is despite all the arguments in US schools about whether to teach evolution vs. creationism (or whatever fancy name is the flavour of the day) everytime there is a concern about a new disease evolving an spreading e.g. SARS, bird flu, swine flu etc. no politician stands up and says that we should do nothing because viruses can't evolve. So when lives are on the line people really do believe in science to help and guide them but if they do not see an immediate threat to their well being then they'll happily undermine and ignore it to keep up their own standard of living.

Comment Pheasant Hunting (Score 1) 289

Does it matter if the drone operator was in the wrong? That does not give the hillbilly permission to shoot it.

Why not? In most countries you are legally allowed to shoot game birds which are on your property provided that you do it safely. This even applies if the birds have been fed and raised and used to stock a piece of land for hunting e.g. pheasant woods in the UK. If the birds leave your land and fly over a neighbours that neighbour is allowed to shoot and keep the birds. If you fly a drone over someone else's private property why should the same rules not apply provided that it is shot in a safe manner?

Comment Network providers not homes (Score 1) 75

1Tbs unless offered at a good price, would be useless for most homes....Perhaps if I had a 4k TV it may be more important

Try 40,000 4k TVs: Netflix 4k takes 25 Mbps. I don't expect to see this technology in the home anytime soon except perhaps in some selected test areas. There is no 'killer app' which needs this much bandwidth in the home at the moment. If it is cheap enough to act as a home link they would be better off marketing it as a replacement for 10Gb network links and switches. I could easily imagine using that sort of bandwidth for analysis of research data on a cluster in a data centre. Why would you aim it at homes to start with?

Comment Re:...and Accuracy (Score 1) 111

I think someone didn't understand his physics course very well. Being in a different frame of reference does not affect a clock's accuracy.

Actually since I'm now the one at the front giving the lectures I'm petty confident I do understand my own physics courses! ;-) Being in a different frame does affect a clock's accuracy when I am making a measurement because time is local. The moment you are in a different frame the accuracy of the clock is limited at best by the accuracy with which you can determine the frame of the clock relative to your own.

In fact this is now the limiting factor in the accuracy of clocks since they can now make clocks which are accurate to 1s in 15 billion years at which point things the the floor of the building you are on start to matter. If they ever make these portable and cheap there are going to be some really interesting applications as well as some fun lecture demos.

Comment Extra pedantic... (Score 2) 111

And for pedants: Yes, technically nothing in the observable universe is theoretically "free" of Earth's gravitational influence

Actually if you want to be extra pedantic that may not be quite true. Parts of the universe which we can observe today (and so are in the observable universe) may by now be causally disconnected from us due to the accelerating expansion of the universe and so no longer feel the Earth's gravity. Of course we really don't know too much about what is driving the acceleration so perhaps this does not apply but it just goes to show that it is best not to make sweeping statements about the universe when we know so little about it: at least 95% of what it is made of is so far unknown to science.

Comment ...and Accuracy (Score 5, Interesting) 111

It probably won't stay that accurate for that long either if it is in space because it is in a different frame of reference and so relativistic effects, including those from general relativity, will build up. This is why the GPS satellites have to have their clocks corrected to stay accurate within the tolerances required. The shift per day for GPS is around 38 microseconds per day which if it is the same for this satellite means that in 26,316 years the clock will be off by one second. This is still a long time but a lot, lot less than 1 billion years.

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