The method of confinement does not change the physics in any way or form. You have electrons, you have ions. The "cross section" for ion/electron collisions that give xrays is just massively higher than fusion cross sections.
First off the activation radioactivity is what is called low grade waste at worst. Proper material choice would mean that it is totally harmless in under a few decades at most. The vast majority of the radiation disappears in just hours to days. As for neutron damage, there are more than a number of ways to deal with this, such as in situ annealing, or liquid blankets, or non structural neutron shields. Also material choice is much much easier with fusion since you don't need to care about neutron economy.
Unfortunately, you need something like 18 parts tritium to get one part He3..
Tritium decays into 3He with a half live of 12 years. 1 ton of T will decay into.5 tons of 3He in 12 years. In 24 years you have.75 tons of 3He. However that is not what is ment with breading. DD reaction has a 50/50 branching ratio with DD->T+p and DD->3He+n . The 3He has quite a low reaction cross section will tend not to burn completely where the T will. ie you end up with 3He in the fusion ash. You could optimize this to breed 3He for fusion applications where neutrons shielding is to cumbersome.
I wouldn't hold your breath. The data and the theory is against it. X ray cooling is massively higher in p+B11. So high in fact that you must pump more energy in than you get out, aka it cannot "ignite". Buzzard just said something along the lines of " they are all wrong". No explanation or anything. That's bad science right there and a sure sign of crack-pottery.
OTOH Lerner has addressed this issue and come up with a mechanism that could reduce x ray cooling. He does not sweep it under the carpet. That's a really good sign, however i still think getting DD to work (1000x times easier) would make more sense. You still get to be the guy that made fusion work. You would never have to worry about funding again.
Also even if we have p+B11 or 3He+3He fusion then both DD and DT will still be used. Because the power density is much higher and i don't think in the end neutrons will be that hard to deal with.
So fusion will have the same long-term radioactive waste disposal problems as fission power currently does.
No it doesn't. Not even within 100 orders of magnitude.
Most of the waste from a fission plant is from the many tons of fuel which a fusion plant does not have. The only waste from a fusion plant is activation products from the structure. Activation via neutron bombardment results is low level and short term radioactive waste. If you choose your materials wisely, probably would be safe in less than 20 years--in fact most of the radiation disappears in just days. It is even much easier to choose materials wisely since you don't need worry about neutron economy.
I ran some numbers above and we seem to arrive at different results. I calculated that you would need 30 million tons per year of regolith for a 1GW plant. I assume a He3 concentration of.01ppm.
Also everyone seems to forget that if you have He3 fusion, you have DD fusion. Neutrons are just not going to be that expensive to deal with, and for the special cases where you do want He3 you can use the ash from DD fusion plants.
He3+He3 gives 12.9MeV of energy per reaction. Thus 1 mol gives 619GJ, or 206 GJ per gram. Assume 1.5 GW power station would produce an average of 1GW all year. That is 31.5e15 J for the year. Assume a 50% efficiency and we need 306 kg of He3 per year. At STP that is about 2000 cubic meters of He3. Now in the Luna surface He3 is only at.01ppm. So at 100% mining efficiency we need to process 30 million tons of rock. In reality you would be very lucky to get 50% efficiency and you still need to consider how much of that He3 you need to burn to run the mining operation. So it is probably closer to 60-100million tons of Luna rock per year.
And thats for just one power station.
Now lets consider the fact that D+T fusion is not here yet and that He3 fusion is more than a 1000 times harder to do. In fact if you can run a He3 fusion plant you can run a DD fusion plant for a fraction of the cost since it is more that 10 times easier to do. Also the ash from DD is He3! It would be cheaper to have DD fusion He3 breeder reactors, than to mine the moon.
He3 is something moon fans bring up since they can't think of any other reason to go there.
The address space of IPv6 is truly massive. However it is not meant to be used the way IPv4 is used. Hell I am not sure you could and have practically sized routing tables. The idea is that the address is highly structured to ease routing and other things. Seriously, this time round they really added a lot of "space" to the address to really cover future expansion. Don't forget IPv4 has been good enough till 2010. By extrapolation IPv6 should be "more than enough for everyone".
You get a lot more that 256 address for your home network if IPv6 is done the way it is suppose to be done.
Note that having a IP==Computer also doesn't change the ruling from the Judges reasoning either, they did raid the right place, he did have that IP number when the offense was committed. Getting a new IP number every few hours from the ISP does *not* give you extra privacy and NAT does not give you any security.
And if you really want, there is the "get a random IPv6 address" option anyway.
And in the process doomed a large number of future patients when the pharmaceutical companies couldn't pay for the cost of producing future medications.
Please don't tell me you believe this tripe. I have worked for some of these companies. Public money makes up the vast majority of the cost of at least the level 2 and 3 trials. They charge an arm and a leg "to recover costs" that you already paid as tax. And because they can. The idea that you can use free market forces for medicine is psychotic.
I am a New Zealander who left a $80k commercial job because i didn't enjoy it. I get more than 35k but a lot less than 80k. I am currently living in the EU.
Money isn't everything. And in science... well it is not why we are here.
Unfortunately very true. Science is just like every other human endeavor. We have our dogma, our prejudices and all the rest. And it will be a cold day in hell before we give them up. Only non practicing scientists go on and on about the scientific method....
As a Post Doc for 5 years now. I can say that perhaps it should have been this way sooner. Tenure would be great personally, but i think its stupid as a general rule, I mean where else do you get such a thing? I would quite like to take a permanent PostDoc job. The money is good enough (you are never here for the money) and currently i get stuck with department rules of the max time you are allowed to be a post doc.
$25 EU gets me 6 months of prepay and that includes roaming. I doubt i could do that with data, at whcih point one has to ask, what is the point of a smart phone?
You know that there are people working on the more cheaply thing--even at CERN. There are real physically limits to what you can do and with what. The LHC is at those limits with todays technology. We are not in fact as stupid as you seem to think we are.
Incidentally more than 18 top notch physics department are involved and benefit from the LHC.
You mean less than half the scientists working in Vienna alone? And 140k per scientist is totally useless if they don't have the tools to do stuff. 140K won't buy you much in the way of instrumentation in any field.
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Nothing in LEO will last in orbit for millions of years. You need to be more than a few 1000 km up to get that kind of orbital lifetime (aka not LEO).
The method of confinement does not change the physics in any way or form. You have electrons, you have ions. The "cross section" for ion/electron collisions that give xrays is just massively higher than fusion cross sections.
Unfortunately, you need something like 18 parts tritium to get one part He3..
Tritium decays into 3He with a half live of 12 years. 1 ton of T will decay into .5 tons of 3He in 12 years. In 24 years you have .75 tons of 3He. However that is not what is ment with breading. DD reaction has a 50/50 branching ratio with DD->T+p and DD->3He+n . The 3He has quite a low reaction cross section will tend not to burn completely where the T will. ie you end up with 3He in the fusion ash. You could optimize this to breed 3He for fusion applications where neutrons shielding is to cumbersome.
I wouldn't hold your breath. The data and the theory is against it. X ray cooling is massively higher in p+B11. So high in fact that you must pump more energy in than you get out, aka it cannot "ignite". Buzzard just said something along the lines of " they are all wrong". No explanation or anything. That's bad science right there and a sure sign of crack-pottery.
OTOH Lerner has addressed this issue and come up with a mechanism that could reduce x ray cooling. He does not sweep it under the carpet. That's a really good sign, however i still think getting DD to work (1000x times easier) would make more sense. You still get to be the guy that made fusion work. You would never have to worry about funding again.
Also even if we have p+B11 or 3He+3He fusion then both DD and DT will still be used. Because the power density is much higher and i don't think in the end neutrons will be that hard to deal with.
Seriously, this knee-jerk anti-government sentiment is getting pretty bad.
getting? You mean it is something new. Hell my Great Grandfather had the same anti-government sentiment.
I think you mean 4He. There is no such thing as 2He.
So fusion will have the same long-term radioactive waste disposal problems as fission power currently does.
No it doesn't. Not even within 100 orders of magnitude.
Most of the waste from a fission plant is from the many tons of fuel which a fusion plant does not have. The only waste from a fusion plant is activation products from the structure. Activation via neutron bombardment results is low level and short term radioactive waste. If you choose your materials wisely, probably would be safe in less than 20 years--in fact most of the radiation disappears in just days. It is even much easier to choose materials wisely since you don't need worry about neutron economy.
I ran some numbers above and we seem to arrive at different results. I calculated that you would need 30 million tons per year of regolith for a 1GW plant. I assume a He3 concentration of .01ppm.
Also everyone seems to forget that if you have He3 fusion, you have DD fusion. Neutrons are just not going to be that expensive to deal with, and for the special cases where you do want He3 you can use the ash from DD fusion plants.
Lets run some numbers.
.01ppm. So at 100% mining efficiency we need to process 30 million tons of rock. In reality you would be very lucky to get 50% efficiency and you still need to consider how much of that He3 you need to burn to run the mining operation. So it is probably closer to 60-100million tons of Luna rock per year.
He3+He3 gives 12.9MeV of energy per reaction. Thus 1 mol gives 619GJ, or 206 GJ per gram. Assume 1.5 GW power station would produce an average of 1GW all year. That is 31.5e15 J for the year. Assume a 50% efficiency and we need 306 kg of He3 per year. At STP that is about 2000 cubic meters of He3. Now in the Luna surface He3 is only at
And thats for just one power station.
Now lets consider the fact that D+T fusion is not here yet and that He3 fusion is more than a 1000 times harder to do. In fact if you can run a He3 fusion plant you can run a DD fusion plant for a fraction of the cost since it is more that 10 times easier to do. Also the ash from DD is He3! It would be cheaper to have DD fusion He3 breeder reactors, than to mine the moon.
He3 is something moon fans bring up since they can't think of any other reason to go there.
Do you think that various intelligent services don't already have something like this?
There is a catch. Smaller lens means less light. There are very real limits. How far we are from them, i can't be bothered to calculate.
Each cell in your body could have their own IP number... Cabling it up could be hard.
The address space of IPv6 is truly massive. However it is not meant to be used the way IPv4 is used. Hell I am not sure you could and have practically sized routing tables. The idea is that the address is highly structured to ease routing and other things. Seriously, this time round they really added a lot of "space" to the address to really cover future expansion. Don't forget IPv4 has been good enough till 2010. By extrapolation IPv6 should be "more than enough for everyone".
You get a lot more that 256 address for your home network if IPv6 is done the way it is suppose to be done.
Note that having a IP==Computer also doesn't change the ruling from the Judges reasoning either, they did raid the right place, he did have that IP number when the offense was committed. Getting a new IP number every few hours from the ISP does *not* give you extra privacy and NAT does not give you any security.
And if you really want, there is the "get a random IPv6 address" option anyway.
Depriving you of a song because you can't afford it, is not the same as letting you suffer because you can't afford the treatment.
And as someone who as worked with these companies, I assure you there are plenty of folks who don't give a rats arse about curing people.
And are you sure that this new medicine is really is effective...
And in the process doomed a large number of future patients when the pharmaceutical companies couldn't pay for the cost of producing future medications.
Please don't tell me you believe this tripe. I have worked for some of these companies. Public money makes up the vast majority of the cost of at least the level 2 and 3 trials. They charge an arm and a leg "to recover costs" that you already paid as tax. And because they can. The idea that you can use free market forces for medicine is psychotic.
I am a New Zealander who left a $80k commercial job because i didn't enjoy it. I get more than 35k but a lot less than 80k. I am currently living in the EU.
Money isn't everything. And in science... well it is not why we are here.
Unfortunately very true. Science is just like every other human endeavor. We have our dogma, our prejudices and all the rest. And it will be a cold day in hell before we give them up. Only non practicing scientists go on and on about the scientific method....
As a Post Doc for 5 years now. I can say that perhaps it should have been this way sooner. Tenure would be great personally, but i think its stupid as a general rule, I mean where else do you get such a thing? I would quite like to take a permanent PostDoc job. The money is good enough (you are never here for the money) and currently i get stuck with department rules of the max time you are allowed to be a post doc.
And torturing POWs is also a war crime. Gitmo is exempt, haven't you heard.
Why should it be limited to only US citizens. Are not all men and women created equal under God? Or however its phrased.
You know in my country US citizens have a right to a fair trial and representation and everything, just like every other foreigner.
I would agree. I is really hard to anonymize some types of data. Location data with a time stamps seems particularly difficult.
$25 EU gets me 6 months of prepay and that includes roaming. I doubt i could do that with data, at whcih point one has to ask, what is the point of a smart phone?
We have had fusion bombs for quite some time. We have the basic Science. We don't have the detailed engineering for fusion as a energy source.
You know that there are people working on the more cheaply thing--even at CERN. There are real physically limits to what you can do and with what. The LHC is at those limits with todays technology. We are not in fact as stupid as you seem to think we are.
Incidentally more than 18 top notch physics department are involved and benefit from the LHC.
You mean less than half the scientists working in Vienna alone? And 140k per scientist is totally useless if they don't have the tools to do stuff. 140K won't buy you much in the way of instrumentation in any field.