, it has to count as a pretty significant difference, though.
Well, even if the difference in mass isn't all that big (you need a _really_ accurate measurement to actually spot it), tiny amounts of mass still translate into huge (as in "E = m * c^2"-huge) amounts of energy.
As a laser physicist... REALLY? Mass deficit from binding energy in molecular bindings or even nuclei is only a small fraction of the total mass.
I would guess that that's the reason why it is so hard to observe quarks. Chemical bindings and nuclear bindings are low-energy enough to mess with on a kitchen table-scale, but if you want to delve into the world of sub-atomic particles you need a honkin' big particle accelerator that consumes a city-equivalent of power.
So I am obviously not understanding how the masses of the quarks correlate to the masses of the fermions. What am I missing here?
IANAPP (particle physicist), but I guess you're missing the equivalent to the "binding energy". Just like the mass of an atomic nucleus isn't equal to the sum of the masses of the protons and neutrons in it.
Ignorance of the law is no defense, at least in English law;
Well, ignorance means "you don't know, but you could have known". In this case, you couldn't have known since you were actively denied access to the legal texts in question.
In that case, you'd be trying to add water to the ocean, through a very thin straw.
What if it's oxygen?
Ok, if we managed to raise the atmospheric oxgen content significantly above 25%, we'd be in trouble. Though, it'd be like trying to add water to Lake Michigan, through a very thin straw.
CO2 is no more a pollutant than nitrogen or oxygen.
Oh? Which industrial processes produce significant amounts of N2 or O2 as waste products? Please enlighten me.
And as far as toxicitiy goes, your body can tolerate _lots_ of N2, quite a bit of O2, but not all that much CO2.
There is no proof of any kind that life has ever existed anywhere other than Earth, ever. In the entire universe. That's not isolationist Creationist babble, that's current scientific fact.
Another scientific fact: Absence of evidence is not equal to evidence of absence. Especially when we haven't even been looking for evidence yet.
The nearest galaxy of any size is over 2.5 million light-years away.
True, but not really relevant for this discussion.
There aren't very many stars within 500 light-years of earth...
Can you define "not very many"?
A first guess would be that the sphere of 500 ly radius around Earth would contain (100,000,000,000 * (500^3) / (100,000^3)) = 12,500 stars. Of course, this makes some assumptions (uniform star distribution, spherical shape of the Milky way) that aren't true, but it's a good first guess. Accounting for the disc shape of the Milky way would probably increase this number quite a bit.
At 0.1c, a 5 ly journey can be completed within a human lifetime.
But the spaceship would still need to be virtually self-sufficient, and also be able to cope with changes of the crew due to, um, human activities (e.g. dying, procreation, etc). It'd have to be a generation ship, and having it travel farther would mostly mean either more stops for picking up fuel and other raw materials, or loading it with more of the same before it is launched.
The figures I quoted were CO2 emission figures rather than energy consumption numbers, so the energy source has already been taken into consideration. The high speed trains used in this study are the French ones, which use a lot of hydro and nuclear power. Even so, they still emit more CO2 per passenger-km than a long haul flight.
I'm sorry? The only thing that can be derived from the diagram on the page is that high-speed trains, if their electricity is solely generated from coal, can result in higher CO2 emissions per passenger-mile than that of a long-haul flight.
climatologists will need to be right more than 50% of the time if they want me to believe them. Heck just this past weekend the only thing they predicted correctly was the daily highs and lows.
And you'll need to stop confusing climatologists with meteorologists.
The question isn't whether it is special, but HOW special.
Exactly. What's the probability of forming a "solar system like" planetary system ? 1:10? 1:1000? 1:1000000? 1:1000000000? The first two would still give us "lots" of hits inside our galaxy, while still being "uncommon".
Dangit, get some more planet-finding telescopes out there, on the double! We need data to back up the hypothesis.
Though the graph shows CO2 emissions rather than fuel consumption, it should be clear that a high-speed train such as the TGV or the Chinese one draws a massive amount of power to maintain its speed. And airplanes do not require all that much fuel to stay airborne once they reach cruising altitude in thinner layers of air; it's the takeoff that requires the tons of fuel. That's why an aircraft wins on the long haul, where the expense of taking off is spread out over more passenger-miles.
Can you run a passenger plane (at least partially) on nuclear power? Hydro? Wind? Tidal? Geothermal? Solar? Any currently-available (sorry, BTL isn't just there yet), non-fossil-fuel power?
And with these trains, you wouldn't cover the distances meant by "long-haul" flights - you'd cover all the short- to medium haul flights where the plane can't play its trump card that well.
While I acknowledge the effort, time and rigor that many astrophysicists have put into studying these phenomena, I still feel that dark matter, a substance which is invisible, intangible, and undetectable expect through its gravitational effects is too far of a step for physics to take without more evidence.
I have to ask - why ? From what we know, there are four forces (strong, weak, electromagnetic, gravitation) that we can use to detect particles. We already know a lot of particles that cannot be detected by one or more of there (e.g. neutrons cannot be detected by looking at the electromagnetic force, photons and electrons cannot be detected if you look at strong force interactions, neutrinos cannot be detected from observing strong or electromagnetic force interactions, etc). Why should a family of particles that mostly interacts gravitationally (and maybe also, occasionally, weakly) be "too far of a step" ?
We already find it quite hard to detect neutrinos, and there's literally bajillions of them passing through Earth every second.
Are you really sure that you've got "true unlimited"?
I'm asking that because unless you've transferred stuff at or near your maximum bandwith 24/7 for about half a year, and haven't gotten any reaction from your ISP (throttling, nasty letters, unexpected outages, whatever), then you're just believing that you have "true unlimited".
The parties will become more and more extreme to further contrast themselves to each other.
Actually, game theory suggests the opposite. And it's true. Compared to parties in other countries, the two large parties in the US are remarkably alike.
No, such a man, if that is Obama, might become the "Leader of the Free World" in five months. Where was this idiot in civics class? Does he think a president elect moves into the White House in November?
It's end of August now (come out of the basement and check if you don't believe me). Five months from now is... end of January.
If Vista were a better (leaner, faster, more secure) Windows XP, it'd be flying off the shelves now. Instead, they've added bloat, eyecandy and a whole load of manure that no one wants, while kicking "legacy" users in the face (DirectX 10, anyone ?)
So, yeah, if MS had actually spent all that time to refactor/improve/bugfix XP, they'd have a splendid product now that people would be eager to buy.
If you're conservative when you're young, you have no heart- If you're liberal when you're old, you have no brain-
Winston Churchill (?)
Misquoted. Easy to see since Churchill wouldn't have said "liberal" when he meant something along the lines of "communist", "socialist" or "social democrat". Saying "liberal" when talking about one of the latter three things is a thoroughly American thing. "Liberal" parties in the rest of the world are more like what Americans know as "Libertarians", just usually a bit more sane.
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Well, even if the difference in mass isn't all that big (you need a _really_ accurate measurement to actually spot it), tiny amounts of mass still translate into huge (as in "E = m * c^2"-huge) amounts of energy.
I would guess that that's the reason why it is so hard to observe quarks. Chemical bindings and nuclear bindings are low-energy enough to mess with on a kitchen table-scale, but if you want to delve into the world of sub-atomic particles you need a honkin' big particle accelerator that consumes a city-equivalent of power.
So I am obviously not understanding how the masses of the quarks correlate to the masses of the fermions. What am I missing here?
IANAPP (particle physicist), but I guess you're missing the equivalent to the "binding energy". Just like the mass of an atomic nucleus isn't equal to the sum of the masses of the protons and neutrons in it.
Ignorance of the law is no defense, at least in English law;
Well, ignorance means "you don't know, but you could have known". In this case, you couldn't have known since you were actively denied access to the legal texts in question.
In that case, you'd be trying to add water to the ocean, through a very thin straw.
What if it's oxygen?
Ok, if we managed to raise the atmospheric oxgen content significantly above 25%, we'd be in trouble. Though, it'd be like trying to add water to Lake Michigan, through a very thin straw.
CO2 is no more a pollutant than nitrogen or oxygen.
Oh? Which industrial processes produce significant amounts of N2 or O2 as waste products? Please enlighten me.
And as far as toxicitiy goes, your body can tolerate _lots_ of N2, quite a bit of O2, but not all that much CO2.
Another scientific fact: Absence of evidence is not equal to evidence of absence. Especially when we haven't even been looking for evidence yet.
Yes. It also contains over 100,000,000,000 stars.
The nearest galaxy of any size is over 2.5 million light-years away.
True, but not really relevant for this discussion.
There aren't very many stars within 500 light-years of earth...
Can you define "not very many"?
A first guess would be that the sphere of 500 ly radius around Earth would contain (100,000,000,000 * (500^3) / (100,000^3)) = 12,500 stars. Of course, this makes some assumptions (uniform star distribution, spherical shape of the Milky way) that aren't true, but it's a good first guess. Accounting for the disc shape of the Milky way would probably increase this number quite a bit.
But the spaceship would still need to be virtually self-sufficient, and also be able to cope with changes of the crew due to, um, human activities (e.g. dying, procreation, etc). It'd have to be a generation ship, and having it travel farther would mostly mean either more stops for picking up fuel and other raw materials, or loading it with more of the same before it is launched.
The figures I quoted were CO2 emission figures rather than energy consumption numbers, so the energy source has already been taken into consideration. The high speed trains used in this study are the French ones, which use a lot of hydro and nuclear power. Even so, they still emit more CO2 per passenger-km than a long haul flight.
I'm sorry? The only thing that can be derived from the diagram on the page is that high-speed trains, if their electricity is solely generated from coal, can result in higher CO2 emissions per passenger-mile than that of a long-haul flight.
Yes, as long as you don't have to obey the laws of thermodynamics.
Oh wait ...
And you'll need to stop confusing climatologists with meteorologists.
Only uncommon. I would have thought our solar system is at least rare, if not epic. Maybe even legendary!
I would assume that once traveling 5 lightyears is feasible, so would be 50 or 500 lightyears.
The question isn't whether it is special, but HOW special.
Exactly. What's the probability of forming a "solar system like" planetary system ? 1:10? 1:1000? 1:1000000? 1:1000000000? The first two would still give us "lots" of hits inside our galaxy, while still being "uncommon".
Dangit, get some more planet-finding telescopes out there, on the double! We need data to back up the hypothesis.
Though the graph shows CO2 emissions rather than fuel consumption, it should be clear that a high-speed train such as the TGV or the Chinese one draws a massive amount of power to maintain its speed. And airplanes do not require all that much fuel to stay airborne once they reach cruising altitude in thinner layers of air; it's the takeoff that requires the tons of fuel. That's why an aircraft wins on the long haul, where the expense of taking off is spread out over more passenger-miles.
Can you run a passenger plane (at least partially) on nuclear power? Hydro? Wind? Tidal? Geothermal? Solar? Any currently-available (sorry, BTL isn't just there yet), non-fossil-fuel power?
And with these trains, you wouldn't cover the distances meant by "long-haul" flights - you'd cover all the short- to medium haul flights where the plane can't play its trump card that well.
I have to ask - why ? From what we know, there are four forces (strong, weak, electromagnetic, gravitation) that we can use to detect particles. We already know a lot of particles that cannot be detected by one or more of there (e.g. neutrons cannot be detected by looking at the electromagnetic force, photons and electrons cannot be detected if you look at strong force interactions, neutrinos cannot be detected from observing strong or electromagnetic force interactions, etc). Why should a family of particles that mostly interacts gravitationally (and maybe also, occasionally, weakly) be "too far of a step" ?
We already find it quite hard to detect neutrinos, and there's literally bajillions of them passing through Earth every second.
I use this example from time to time as most people who live in the US have no idea how backward the US can be in certain areas.
You've got that all wrong! You need to listen to more prop^H^H^H^Hcommercials. Repeat after me:
Cars good! (Nevermind the traffic jams and all the other problems LALALALALA!!)
Planes good! (Only if you're not on THE LIST, citizen!)
Trains bad! Only communists and poor people use trains! You don't want to be a communist or a poor person, do you?!
But then again, that's just web surfing, e-mail, a few hours of MMORPG per day, and the occasional download.
Are you really sure that you've got "true unlimited"?
I'm asking that because unless you've transferred stuff at or near your maximum bandwith 24/7 for about half a year, and haven't gotten any reaction from your ISP (throttling, nasty letters, unexpected outages, whatever), then you're just believing that you have "true unlimited".
Yes, in exactly the same way that the DPRK is democratic.
If police enter without knocking and showing a valid warrant, they are just like any other armed person breaking into a house.
With the difference that you and anyone else in the house will end up dead and the surviving police officers will get promoted. Really good plan.
Actually, game theory suggests the opposite. And it's true. Compared to parties in other countries, the two large parties in the US are remarkably alike.
It's end of August now (come out of the basement and check if you don't believe me). Five months from now is ... end of January.
It has worked so well for Vista....
If Vista were a better (leaner, faster, more secure) Windows XP, it'd be flying off the shelves now. Instead, they've added bloat, eyecandy and a whole load of manure that no one wants, while kicking "legacy" users in the face (DirectX 10, anyone ?)
So, yeah, if MS had actually spent all that time to refactor/improve/bugfix XP, they'd have a splendid product now that people would be eager to buy.
If you're conservative when you're young, you have no heart-
If you're liberal when you're old, you have no brain-
Winston Churchill (?)
Misquoted. Easy to see since Churchill wouldn't have said "liberal" when he meant something along the lines of "communist", "socialist" or "social democrat". Saying "liberal" when talking about one of the latter three things is a thoroughly American thing. "Liberal" parties in the rest of the world are more like what Americans know as "Libertarians", just usually a bit more sane.
http://en.wikiquote.org/wiki/Churchill