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Comment: ...which is therefore not parallel (Score 4, Informative) 150

by Roger W Moore (#48945117) Attached to: There Is No "You" In a Parallel Universe

Different matter distributions == a universe in which said parallel universe which is inherently different than what we see around us.

I think there is some confusion over what "parallel" universe means. This is generally taken to be a universe which has been an exact parallel of our own universe up to some point after which it diverges i.e. everything is the same up to some point in time. In the quantum multiverse interpretation of QM this happens for each possible result of collapsing the wave function.

I've never heard of this ever being associated with multiple 'universes' from inflation because QM requires that the universes interact before they separate (this is how it explains the self interference of a single particle) whereas inflation requires that the universes be causally disconnected after their creation i.e. inflationary universes are just different universes, not parallel ones. So I think the author of the article got himself rather confused.

Comment: Re:...on intelligence and technological advancemen (Score 1) 278

Really you have two options here. Either that Martian life would be entirely different to us in which case it is unlikely going to be even able to survive on Earth let alone devour anything or it is somehow similar to life on Earth in which case would it really be any worse that the collection of highly infectious, nasty bugs we already have in labs around the planet?

Certain science fiction loves to go on about alien superbugs because they make good stories but I expect that in this regard reality will be a lot more boring, and safer, than fiction.

Comment: The Hague? (Score 1) 164

Interesting. I was confused by this since I was taught as a kid that The Hague was the capital of the Netherlands and, if Wikipedia is to be believed, that is still where the government sits even though it seems that Dutch law defines Amsterdam as the capital (which was something I'd never heard of until today). So apparently at least in the UK we used to be taught based on the definition of capital, i.e. where the ruling government presides, and not whatever local laws would like to call a capital.

Comment: ...on intelligence and technological advancement (Score 5, Insightful) 278

Actually I would think it depends more on how intelligent and how advanced it is. Microbial life on Mars will hardly instill much fear but a lot of curiosity. An advanced space craft appearing in orbit and contacting us will generate far more fear...but still a lot of curiosity about their technology. So I'd say that curiosity is the one constant regardless of what type of life we find. Whether we fear it will depend on the details.

Comment: Re:Travel is hard, Radio is not (Score 1) 236

by Roger W Moore (#48921897) Attached to: Gamma-ray Bursts May Explain Fermi's Paradox

then it is more probable our data point falls around the middle

My point is though that without knowing the width of that distribution you have no idea how wide the 'middle' is: if your average time to evolve intelligence is 30+/-20 billion years we are still well within 2 sigma from the mean. This could make intelligent life sufficiently rare so that we could easily be the first in our galaxy given the age of the universe. With billions of galaxies there could still be more advanced intelligent life in a galaxy far, far away but we would never know about them.

Comment: Travel is hard, Radio is not (Score 1) 236

by Roger W Moore (#48919943) Attached to: Gamma-ray Bursts May Explain Fermi's Paradox

An alternate "simplest" explanation (though less likely) is that we are first.

Just curious but why do you say that? We have no clue how likely intelligent life is to evolve. All we know is that it has happened once, and it took 3.5 billion years from the formation of the first like on Earth. Suppose that this was very much faster than average and the the mean time for intelligent life to evolve (once life itself has started) is 30 billion years? Such a long time would hugely reduce the number of intelligent species since you need a very stable environment for a long period of time and even then you have to get lucky.

Trying to quantify what you don't know is a mug's order to be able to do it you really need to know what you don't know. If anything I would argue that there is, perhaps, some weak evidence for intelligent life being rare: travel might be hard but radio is easy. We have not heard ET's broadcasts which would suggest perhaps that there is no intelligent life nearby (or they use some technology beyond EM waves).

Comment: Re:"A hangar in Mojave" (Score 3, Informative) 38

by Bruce Perens (#48908157) Attached to: Virgin Galactic Dumps Scaled Composites For Spaceship Two

That's actually what it's like at "Mojave Spaceport". Hangers of small aviation practicioners and their junk. Gary Hudson, Burt Rutan, etc. Old aircraft and parts strewn about. Left-over facilities from Rotary Rocket used by flight schools. A medium-sized facility for Orbital. Some big facilities for BAE, etc. An aircraft graveyard next door.

Comment: Global warming = doomsday? (Score 2) 216

by Roger W Moore (#48898239) Attached to: Doomsday Clock Moved Two Minutes Forward, To 23:57

you have to wonder why anyone would put any stock in it.

Especially given that they now track global warming. Nuclear war is a doomsday scenario but global warming is most certainly not. It may cause economic hardship and the displacement of populations as sea levels rise plus the need to alter crops etc. but it is not going to wipe humanity off the face of the earth. Since the clock is supposedly set by scientists if they can be so wrong about something scientific then I have little faith they can predict the likelihood of nuclear war either given that this depends on politics.

Comment: Re:They already have (Score 1) 666

by Bruce Perens (#48897151) Attached to: US Senate Set To Vote On Whether Climate Change Is a Hoax

There is no reason that we have to pick one and abandon work on the others. I don't see that the same resources go into solving more than one, except that the meteor and volcano problem have one solution in common - be on another planet when it happens.

The clathrate problem and nuclear war have the potential to end the human race while it is still on one planet, so we need to solve both of them ASAP.

Comment: Re:They already have (Score 1) 666

by Bruce Perens (#48887305) Attached to: US Senate Set To Vote On Whether Climate Change Is a Hoax

Sure, there are going to be mediating forces in the environment. Melting is an obvious one. The positive feedbacks have been getting the most attention because they are really scary. It appears that there are gas clathrates in the ground and under water that can come out at a certain temperature. The worst case is that we get an event similar to Lake Nyos, but with a somewhat different mechanism and potentially many more dead. The best case is a significant atmospheric input of CO2 and methane that we can't control.

I don't think I have to discount Trenberth. He's trying to correct his model, he isn't saying there is no warming.

Comment: Re:They already have (Score 1) 666

by Bruce Perens (#48884865) Attached to: US Senate Set To Vote On Whether Climate Change Is a Hoax


McKitrick is an economist out of his field. Trenberth and Fasullo cite many of their other papers and the publications to which they were submitted, but it seems mostly not accepted. But their conclusion seems to be that there were other times in recent years that the rate of warming decreased for a time only for it to return to its previous rate. I only see the abstract for Kosaka and Xie, but they state "the multi-decadal warming trend is very likely to continue with greenhouse gas increase."

Comment: Re:They already have (Score 1) 666

by Bruce Perens (#48882193) Attached to: US Senate Set To Vote On Whether Climate Change Is a Hoax

I imagine that the major financial companies make this part of their economic modeling. Most of them do publish weather-related and climate-related advisories regarding commodity and company price trends, etc. How detailed do they get? The wouldn't tell and I am the wrong kind of scientist to ask. Can we make a government or public one? Yes, the level of detail is the big question.

Comment: Re:They already have (Score 1) 666

by Bruce Perens (#48882135) Attached to: US Senate Set To Vote On Whether Climate Change Is a Hoax

Oh, do I have to qualify that for you, like the hottest outside of a period of Milankovitch Forcing? Gee, maybe the Earth's orbit changed, like back then, and we just didn't notice.

Let's take a look at one of the references you cited:

A section of a draft IPCC report, looking at short-term trends, says temperatures are likely to be 0.4 to 1.0 degree Celsius (0.7-1.8F) warmer from 2016-35 than in the two decades to 2005. Rain and snow may increase in areas that already have high precipitation and decline in areas with scarcity, it says.

It sounds like we have reason to be alarmed.

Byte your tongue.