Oh, I'm *all* for investing money into fusion--don't get me wrong. I think the Polywell should get its $200M to build a scaled up prototype, that tokamak fusion should be supported at 10x current levels, that the Superconducting Supercollider ought not to have been cancelled, research into how to get people into space long term (right now people in space is mostly just pissed-away money), PUBLIC research with results FREELY AVAILABLE into better, more drought/salt/disease resistant food crops, and more medical research.
Pay for the extra science by cancelling some wars, reducing non-research defense spending, raising the social security age (I'm sorry, but if you're able to work, you should be contributing, yes you deserve a retirement, but the rest of us NEED you working thanks to really dumb political leadership that YOU elected) and eliminating the cap on social security tax, reforming the medical care system to bring costs down (we pay 2x for worse care? why is that??) eliminating unnecessary corporate and farm subsidies. I'm also for eliminating corporate tax and making up the revenue by taxing individuals on income instead--let's encourage industry in this country and discourage plutocracy, and since corporations just pass tax along to customers, this makes taxation in general less regressive.
I looked at your graph, and the only message it conveys is that someone pulled the idea out of their rear that if we spent more money on fusion research we'd get somewhere, and invented numbers for the investment required and when results would be achieved.
I mean, those curves? They look like a kid scribbling with crayon. There's no iron-clad guarantee that *any* level of investment will lead to a practical fusion reactor. The only serious notion to be derived from that plot is that current US investment levels are insufficient to get anywhere.
And even if we DO achieve a fusion reactor that produces net energy, it may cost more in capital to build the plant than you can pay for by selling the power produced. I.e., it'd be cheaper to build solar plants + energy storage than the fusion plant.
Hello, I'm sorry to say this, but aneutronic fusion is probably never going to be a practical energy source.
There's a reason D-T fusion is the focus. One problem is that all the aneutronic fusion reactions involve higher-Z (higher atomic number) nuclei. Higher Z nuclei have worse energy loss via Bremsstrahlung radiation than the D-T or D-D reactions. In a plasma hot enough to sustain fusion reactions, the electrons and ions are banging against each other, and every hit potentially makes X-rays or gamma rays, converting thermal energy into light. In a reasonable-sized thermal plasma, these photons pretty much just leave without interacting again, thus cooling the plasma.
People have calculated that the energy loss rate from Bremsstrahlung in a thermal plasma composed of atoms capable of doing aneutronic fusion would exceed the rate that the fusion reactions would heat it. Thus, the plasma would cool right off, the flame would in effect "go out" because it would lose heat faster than it created heat via fusion.
In a star, this works out, because a star is so very, very big that the photons from Bremsstrahlung are re-captured within the star: i.e., the heat can't escape because of sheer mass in the way. We're never going to pull that size and density off in a lab or an engineering installation.
Now, if you can somehow arrange for the plasma to NOT be thermal, you may be able to beat this issue. However, keeping a plasma from thermalizing requires a large energy input, and is very hard to arrange for and preserve long enough to get energy from fusions. Inertial confinement might work (laser or Z-pinch or the like), there you potentially have very high densities for maybe "long enough" for Bremsstrahlung not to eat your lunch: I don't know. However, both laser and Z-type installations seem very hard engineering problems.
The wikipedia on "aneutronic fusion" discusses these issues some as well.
Anyway, that's one reason most are happily ignoring aneutronic fusion entirely. Another is that much higher temperatures are required for the aneutronic fusion reactions, and we haven't even got D-T going yet and that is the lowest temperature fusion reaction. D-T is where I would put my money, too, given the results of the physics calculations.
I like the idea of aneutronic fusion, I really like it a lot, but a theoretician has apparently shown it to be impossible to realize. Why? He did some calculations and figured out that the energy loss in a reasonably-sized thermal plasma from Bremsstrahlung radiation, which is a function of the atomic weight of the atoms in the plasma, causes too much energy loss to be sustained by fusing nuclei. The plasma radiates its heat away too fast, and you can't stop the X-rays and gamma rays within the plasma to keep it from cooling.
The Wikipedia article on aneutronic fusion covers this issue some and provides a few references. But the upshot is Bremsstrahlung makes aneutronic fusion a non-starter. It's physically impossible unless you have a VERY LARGE or VERY DENSE ball of plasma--neither of which is achievable in anything like a tokamac.
You *might* be able to get such a reaction to work in, say, a laser-ignited small fusion explosion, or if you can somehow manage to NOT have a thermal plasma. However, both of those are much harder to arrange for than a D-T thermal plasma.
It's really very sad, but DirTy DT reactions with their associated neutrons may be the only thing we have a chance of engineering any time soon!
Point 1: they've taken thimerosol out of most vaccines.
Point 2: We probably get more mercury exposure from burning coal than from CFLs. I personally get most of my mercury exposure from my silver-mercury amalgam fillings. That last one really adds up. CFLs are pretty much innocent, just like you admit vaccines are.
I fully expect to be quarantined if I am unfortunate enough to contract, say, drug resistant TB until I'm either dead or not contagious.
Similarly if I am infected with ebola, pneumonic plague, or a raft of other nasties. Furthermore, I fully support society's right to lock me away should I be infected with one of those.
HIV is barely contagious. However, I believe there are cases where people who have deliberately spread HIV have been locked up, too. But for most people, HIV+ people don't need to be locked up because they have a very low risk of infecting anyone else.
And I think even people with TB don't need to be quarantined if they're taking sufficient measures to stop infecting anyone else.
We have maybe 12 different vaccinations for infants. I read this in a health magazine:
"When a child is born, he or she is literally assaulted by thousands of species of bacteria and viruses that child has never seen before, because they were in the sterile womb environment. Given that, I don't think we need to worry about the relatively small number of shots we give children."
I found that a difficult point to refute--you get born, and suddenly, yes, you're immersed in a bunch of germs. Thousands or maybe millions of types! This is normal, expected, and unavoidable. Yet we're supposed to get worried because we add a dozen or so dead germs to that list of exposure?
This doesn't really address "bunch of foreign chemicals", but I think that the other, inactive components of vaccines can be tested for safety. Even thimerosal, which tested as safe, was removed as a precaution because it had some mercury in it, so what, exactly, are you worried about in the "foreign chemical" arena???
It's not clear to me that fusion can EVER be made practical. It's quite possible that a SMALL fusion plant just can't be made, which leaves you with investing in mega-plants. Then, if you pay more in capital to build a fusion plant than you can recover from selling the power than, say, wind power, no one will ever build a fusion plant.
As an example of the stringent constraints on fusion, did you know that a thermal plasma of reasonable size with elements heavier than hydrogen + helium cools off faster via Bremsstrahlung than it generates heat via fusion? That pretty much leaves us with D-D (harder) and D-T (easier) fusion as possible reactions, both of which produce lots of neutron flux. These neutrons activate many materials and require big thermal conversion units that'll get really, really radioactive. Furthermore, it seems apparent that a thermal plasma fusion plant will have to be "big enough" or it won't be able to sustain burning, pointing at a large capital investment to make it go.
Thus, I have strong doubts that fusion plants can ever be justified as a capital investment vs. an investment in, say, geothermal or wind or fission.
This brings up the question, when the labor market is saturated and there are no jobs for the masses to do, what are the masses supposed to do to eat?
When we have a society where it takes only a few to produce everything people need, and maybe even everything people want, how do we keep everyone employed? Or should we even try? Or do we just degenerate to a state where the "haves" have everything they want, and don't need anything, and the "have nots" have nothing, and don't have any way of earning money to buy anything?
How do you think this'll work? Russia has nukes. China can never invade Russia. They might buy it, though. Or is China buying Russia what you meant by "go for it"?
The supercontinent cycle is driven by the earth's own internal heat, the ringing effect of the impact would probably have damped within days or weeks. I've seen analogies made between the continents on the earth and bits of froth on boiling water: the water pushes the froth around, sometimes it coalesces into one patch, other times it breaks up.
However, the impact might have contributed a fair bit of the heat that drives the supercontinent cycles, either directly with kinetic energy or indirectly by depositing heavy radionuclides, or both.
My understanding of current geological theory is that Pangea is just the most recent of a cyclic occurrence of supercontinents.
There have been multiple time periods in Earth's history when most of the land was in one supercontinent, which then split into continents, only to rejoin again. Wikipedia has the cycle at 300M to 500M years.
I second you on this one. It is why I rarely took any CS classes--the material is so easy to learn. Why? Because people invented the whole field, for the most part, and people designed it so it makes sense.
Physics and math are much harder to learn.... There, in many cases, you are not dealing with something invented by a human mind. A lot of physics (like quantum mechanics) just doesn't really make sense.
Oh, and one more good point I forgot. I read about someone who'd done an unscientific study in the US: they gave a civics test to random people in the street and to people serving in the House.
Guess who scored higher on the civics test?
So if random people perform better than the elected membership, well, why don't we have random people instead of the collection of "winners" we have now?
Simple solution: you hold a lottery among all people of voting age. The losers go serve in the legislature. Lots of good points: 1) Fair 2) Representatives don't owe anyone payback for helping them into office 3) Representatives are truly representative of society (i.e., no lawyer bias, or rich person's bias), and you might even see some homeless people in the legislature for a change 4) When you make the changeover, enforce that any benefits they vote the Legislature membership don't go to them, but to the next "winners" 5) Force service by "well, you either serve in the Legislature, or you serve in prison. Your choice!"
downside: a) could give the bureaucracy too much power--inexperienced legislatures b) people stuck with the job could do a lousy job 'cause they don't really care and resent the duty
So, if DNA has such a hard time traveling in time, how about in the interplanetary/interstellar environment, where UV and radiation exposure can be pretty bad?
I mean, if DNA can't survive on earth, for very long, could viable organisms realistically transit from planet to planet or star system to star system by natural means?
In the past, I've argued that exposure to radiation would eventually degrade to randomness any complex organic molecule in the harsh environment of space. The only shot that something organic traveling at any reasonable speed could get from star to star or even from planet to planet would be either to be massively shielded, or to be metabolically active and continually repairing damage. Also, that "eventually" was a far smaller timescale than, say, star system to star system, or even most likely interplanetary trajectories. And then there's the re-entry problem....
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Oh, I'm *all* for investing money into fusion--don't get me wrong. I think the Polywell should get its $200M to build a scaled up prototype, that tokamak fusion should be supported at 10x current levels, that the Superconducting Supercollider ought not to have been cancelled, research into how to get people into space long term (right now people in space is mostly just pissed-away money), PUBLIC research with results FREELY AVAILABLE into better, more drought/salt/disease resistant food crops, and more medical research.
Pay for the extra science by cancelling some wars, reducing non-research defense spending, raising the social security age (I'm sorry, but if you're able to work, you should be contributing, yes you deserve a retirement, but the rest of us NEED you working thanks to really dumb political leadership that YOU elected) and eliminating the cap on social security tax, reforming the medical care system to bring costs down (we pay 2x for worse care? why is that??) eliminating unnecessary corporate and farm subsidies. I'm also for eliminating corporate tax and making up the revenue by taxing individuals on income instead--let's encourage industry in this country and discourage plutocracy, and since corporations just pass tax along to customers, this makes taxation in general less regressive.
--PM
I looked at your graph, and the only message it conveys is that someone pulled the idea out of their rear that if we spent more money on fusion research we'd get somewhere, and invented numbers for the investment required and when results would be achieved.
I mean, those curves? They look like a kid scribbling with crayon. There's no iron-clad guarantee that *any* level of investment will lead to a practical fusion reactor. The only serious notion to be derived from that plot is that current US investment levels are insufficient to get anywhere.
And even if we DO achieve a fusion reactor that produces net energy, it may cost more in capital to build the plant than you can pay for by selling the power produced. I.e., it'd be cheaper to build solar plants + energy storage than the fusion plant.
--PM
Hello, I'm sorry to say this, but aneutronic fusion is probably never going to be a practical energy source.
There's a reason D-T fusion is the focus. One problem is that all the aneutronic fusion reactions involve higher-Z (higher atomic number) nuclei. Higher Z nuclei have worse energy loss via Bremsstrahlung radiation than the D-T or D-D reactions. In a plasma hot enough to sustain fusion reactions, the electrons and ions are banging against each other, and every hit potentially makes X-rays or gamma rays, converting thermal energy into light. In a reasonable-sized thermal plasma, these photons pretty much just leave without interacting again, thus cooling the plasma.
People have calculated that the energy loss rate from Bremsstrahlung in a thermal plasma composed of atoms capable of doing aneutronic fusion would exceed the rate that the fusion reactions would heat it. Thus, the plasma would cool right off, the flame would in effect "go out" because it would lose heat faster than it created heat via fusion.
In a star, this works out, because a star is so very, very big that the photons from Bremsstrahlung are re-captured within the star: i.e., the heat can't escape because of sheer mass in the way. We're never going to pull that size and density off in a lab or an engineering installation.
Now, if you can somehow arrange for the plasma to NOT be thermal, you may be able to beat this issue. However, keeping a plasma from thermalizing requires a large energy input, and is very hard to arrange for and preserve long enough to get energy from fusions. Inertial confinement might work (laser or Z-pinch or the like), there you potentially have very high densities for maybe "long enough" for Bremsstrahlung not to eat your lunch: I don't know. However, both laser and Z-type installations seem very hard engineering problems.
The wikipedia on "aneutronic fusion" discusses these issues some as well.
Anyway, that's one reason most are happily ignoring aneutronic fusion entirely. Another is that much higher temperatures are required for the aneutronic fusion reactions, and we haven't even got D-T going yet and that is the lowest temperature fusion reaction. D-T is where I would put my money, too, given the results of the physics calculations.
--PM
Under likely laboratory conditions, that is.
I like the idea of aneutronic fusion, I really like it a lot, but a theoretician has apparently shown it to be impossible to realize. Why? He did some calculations and figured out that the energy loss in a reasonably-sized thermal plasma from Bremsstrahlung radiation, which is a function of the atomic weight of the atoms in the plasma, causes too much energy loss to be sustained by fusing nuclei. The plasma radiates its heat away too fast, and you can't stop the X-rays and gamma rays within the plasma to keep it from cooling.
The Wikipedia article on aneutronic fusion covers this issue some and provides a few references. But the upshot is Bremsstrahlung makes aneutronic fusion a non-starter. It's physically impossible unless you have a VERY LARGE or VERY DENSE ball of plasma--neither of which is achievable in anything like a tokamac.
You *might* be able to get such a reaction to work in, say, a laser-ignited small fusion explosion, or if you can somehow manage to NOT have a thermal plasma. However, both of those are much harder to arrange for than a D-T thermal plasma.
It's really very sad, but DirTy DT reactions with their associated neutrons may be the only thing we have a chance of engineering any time soon!
--PeterM
And the bacteria/viruses injected into us are dead (except the live polio vaccine), not alive and kicking like natural exposure.
--PM
I don't think it's enough to cause problems, but you do get mercury from your fillings.
You're correct that methyl mercury (from fish) and elemental mercury (from amalgam) differ a lot in their toxicity to the body.
See these references:
http://www.ncbi.nlm.nih.gov/pubmed/9391753
http://en.wikipedia.org/wiki/Dental_amalgam_controversy
Yes.
Google is your friend:
http://www.nlm.nih.gov/medlineplus/ency/article/002395.htm
http://www.bbc.co.uk/health/physical_health/conditions/motherbabyinfections2.shtml
--PM
Point 1: they've taken thimerosol out of most vaccines.
Point 2: We probably get more mercury exposure from burning coal than from CFLs. I personally get most of my mercury exposure from my silver-mercury amalgam fillings. That last one really adds up. CFLs are pretty much innocent, just like you admit vaccines are.
Hello,
I fully expect to be quarantined if I am unfortunate enough to contract, say, drug resistant TB until I'm either dead or not contagious.
Similarly if I am infected with ebola, pneumonic plague, or a raft of other nasties. Furthermore, I fully support society's right to lock me away should I be infected with one of those.
HIV is barely contagious. However, I believe there are cases where people who have deliberately spread HIV have been locked up, too. But for most people, HIV+ people don't need to be locked up because they have a very low risk of infecting anyone else.
And I think even people with TB don't need to be quarantined if they're taking sufficient measures to stop infecting anyone else.
--PM
Hello,
We have maybe 12 different vaccinations for infants. I read this in a health magazine:
"When a child is born, he or she is literally assaulted by thousands of species of bacteria and viruses that child has never seen before, because they were in the sterile womb environment. Given that, I don't think we need to worry about the relatively small number of shots we give children."
I found that a difficult point to refute--you get born, and suddenly, yes, you're immersed in a bunch of germs. Thousands or maybe millions of types! This is normal, expected, and unavoidable. Yet we're supposed to get worried because we add a dozen or so dead germs to that list of exposure?
This doesn't really address "bunch of foreign chemicals", but I think that the other, inactive components of vaccines can be tested for safety. Even thimerosal, which tested as safe, was removed as a precaution because it had some mercury in it, so what, exactly, are you worried about in the "foreign chemical" arena???
--PeterM
In the Netherlands, scientists get respect. A house and free beer? How cool is that?
Not like the US, where if you're too "smart" you're a "nerd", "geek", a social outcast.
--PM
If, for example, it was broken and never changed. I'd look both ways to check safety and then I'd run the light.
I think this is even legal.
Best,
--PM
Really? Do I live on a different planet? Seems like there's big unemployment and massive underemployment in the US.
Maybe jobs are growing faster in the 3rd world, or the various dictatorships?
--PM
Hello,
It's not clear to me that fusion can EVER be made practical. It's quite possible that a SMALL fusion plant just can't be made, which leaves you with investing in mega-plants. Then, if you pay more in capital to build a fusion plant than you can recover from selling the power than, say, wind power, no one will ever build a fusion plant.
As an example of the stringent constraints on fusion, did you know that a thermal plasma of reasonable size with elements heavier than hydrogen + helium cools off faster via Bremsstrahlung than it generates heat via fusion? That pretty much leaves us with D-D (harder) and D-T (easier) fusion as possible reactions, both of which produce lots of neutron flux. These neutrons activate many materials and require big thermal conversion units that'll get really, really radioactive. Furthermore, it seems apparent that a thermal plasma fusion plant will have to be "big enough" or it won't be able to sustain burning, pointing at a large capital investment to make it go.
Thus, I have strong doubts that fusion plants can ever be justified as a capital investment vs. an investment in, say, geothermal or wind or fission.
Best,
--PM
Not on any scale worth mentioning. It's possible to do, but no one is doing it, so why even MENTION it?
It's just a way for people to rationalize that "oh, we can clean up coal" when in fact no one does clean up coal's CO2.
--PM
This brings up the question, when the labor market is saturated and there are no jobs for the masses to do, what are the masses supposed to do to eat?
When we have a society where it takes only a few to produce everything people need, and maybe even everything people want, how do we keep everyone employed? Or should we even try? Or do we just degenerate to a state where the "haves" have everything they want, and don't need anything, and the "have nots" have nothing, and don't have any way of earning money to buy anything?
--PM
How do you think this'll work? Russia has nukes. China can never invade Russia. They might buy it, though. Or is China buying Russia what you meant by "go for it"?
--PM
My gut tells me different. :)
The supercontinent cycle is driven by the earth's own internal heat, the ringing effect of the impact would probably have damped within days or weeks. I've seen analogies made between the continents on the earth and bits of froth on boiling water: the water pushes the froth around, sometimes it coalesces into one patch, other times it breaks up.
However, the impact might have contributed a fair bit of the heat that drives the supercontinent cycles, either directly with kinetic energy or indirectly by depositing heavy radionuclides, or both.
--PM
Hello,
My understanding of current geological theory is that Pangea is just the most recent of a cyclic occurrence of supercontinents.
There have been multiple time periods in Earth's history when most of the land was in one supercontinent, which then split into continents, only to rejoin again. Wikipedia has the cycle at 300M to 500M years.
Here's the wikipedia article. http://en.wikipedia.org/wiki/Supercontinent_cycle
So, I think your exit would theory contradicts current geological theory.
--PeterM
I second you on this one. It is why I rarely took any CS classes--the material is so easy to learn. Why? Because people invented the whole field, for the most part, and people designed it so it makes sense.
Physics and math are much harder to learn.... There, in many cases, you are not dealing with something invented by a human mind. A lot of physics (like quantum mechanics) just doesn't really make sense.
--PM
I must've had enlightened history teaching, because I was never once required to memorize any dates with just one exception: July 4, 1776.
I'm sorry you were made to memorize stupid dates.
--PM
Oh, and one more good point I forgot. I read about someone who'd done an unscientific study in the US: they gave a civics test to random people in the street and to people serving in the House.
Guess who scored higher on the civics test?
So if random people perform better than the elected membership, well, why don't we have random people instead of the collection of "winners" we have now?
--PM
Simple solution: you hold a lottery among all people of voting age. The losers go serve in the legislature. Lots of good points:
1) Fair
2) Representatives don't owe anyone payback for helping them into office
3) Representatives are truly representative of society (i.e., no lawyer bias, or rich person's bias), and you might even see some homeless people in the legislature for a change
4) When you make the changeover, enforce that any benefits they vote the Legislature membership don't go to them, but to the next "winners"
5) Force service by "well, you either serve in the Legislature, or you serve in prison. Your choice!"
downside:
a) could give the bureaucracy too much power--inexperienced legislatures
b) people stuck with the job could do a lousy job 'cause they don't really care and resent the duty
--PM
So, if DNA has such a hard time traveling in time, how about in the interplanetary/interstellar environment, where UV and radiation exposure can be pretty bad?
I mean, if DNA can't survive on earth, for very long, could viable organisms realistically transit from planet to planet or star system to star system by natural means?
In the past, I've argued that exposure to radiation would eventually degrade to randomness any complex organic molecule in the harsh environment of space. The only shot that something organic traveling at any reasonable speed could get from star to star or even from planet to planet would be either to be massively shielded, or to be metabolically active and continually repairing damage. Also, that "eventually" was a far smaller timescale than, say, star system to star system, or even most likely interplanetary trajectories. And then there's the re-entry problem....
Was I right?
--PM
A backup in your basement does nothing for you if your house burns down/gets flooded/has a catastrophic power surge/whatever.
Where else can you backup offsite?
--PM