Sunday, December 11, 2005

December 2005

A scientist at Lawrence Livermore Laboratory working on greenhouse warming recently pointed out that if the only thing you want to do is sequester c02, then forest is not the long term answer. He is right in the narrow sense, but very wrong in the most important sense.

Our response to Global Warming must include vigorous efforts to plant more forests in critical locations. Climate modelers have determined that a fairly small forest in the center of the Austrailian outback could double the rainfall over the whole contenant. So a new forest as small as 100 square miles could make a huge difference, yet it would be a project larger than we've done as a civilization, and it's just the sort of thing that could make a long term difference.

In a similar way, forest ecosystems must move toward the poles faster than ever before except in astrophysical events, and if we want to have a recovery time on the order of hundreds of years instead of hundreds of thousands of years. then we need to help forests grow in new zones, we need the trees to modify the hydrology, the weather changes, to form the basis of a more sustainable economy.

In the short term, planting forests would counter the spread of deserts, especially when done in conjunction with climate modeling to guide the efforts for best ecosystem effect.

The changes in glaciers will change rivers, and expose new land for tree growth. There is only a short time during which the trees must become established if the soil newly exposed is to be nurtured, or it may be eroded and deposited under the oceans. So Humans must shift what we spend our time doing.

We will also have to move out of low lying area's as the sea rises, and rather than push against the sea, we better become adept at moving, at conserving our marine resources like fish....

Bruce Bagnoli


We need to develop flywheels, fusion, tidal power, hydropower, safe nuclear power, wind power, and learn how to save enough genetic material, genomic information, from species that may be going extinct.

We need to develop alternatives to coal burning , and find ways to make our microprocessor and RAM industries sustainable.

A stable population on the earth at levels of 1-2billion would seem to be one factor that would help if we didn't have to do it suddenly. If through changes in living conditions and standards we could flatten the growth curve, it would undoubtably restrain the rate of growth from this point on.

What I fear is that the

Sunday, August 07, 2005

Fairness demands that societies value the ecosystem, and put resources into both the nourishment and protection of the treasured primordial ecosystems, and that the costs be borne by the larger society and not dumped on the rural folks who, for example, used to be dependent on logging. Present law seems to fall on one side or the other, weakening the mechanism that could protect the ecological legacy.

Here in California, down near Moro Bay, the seashore used to be miles out to sea. This was during the time that modern Humans lived in California. Those humans adjusted to the sea level increase, some dozens of feet, so I imagine our descendents will adjust to the changes brought about by the melting of so many glaciers, so much of the polar ice caps.

I hope that desertification is not allowed to proceed the way it appears to be spreading now, I hope that it is arrested and reversed through the terra-forming here. Desertification is almost irreversible within generations, but climate modeling can guide us to use our efforts in the most intelligent way, the most effective way.

An example is the discovery that a chunk of forest at roughly the center of the continent would double the rainfall across the whole continent (from almost none to some), a very amazing way to influence climate, and to encourage plant growth across a huge area, a lot of biomass. I'm a long way away from believing that a model is enough to start a huge civil engineering effort, but it is time to start thinking along those lines, learning to protect the species left. I fear that the next 300 years will challenge a significant fraction of the species as the disruptions from climate change are worked through.

Anyway, time to feed the cats.

Wednesday, July 06, 2005

In a recent review of high power density systems, the "Z" pinch work done by Sandians in New Mexico was described. These folks have made a huge amount of progress, adapting as they go along and learning to make small devices that surely rival the work done at NIF in California on the road to Fusion in the lab.

The "Z"-pinch machine that they are now upgrading started out as a light ion device, PBFA, and during the experimental campaign it was learned that the light ion approach would be less useful, and that the machine could do some amazing tricks useful in their own right using the basic setup, forgetting the light ions and using the driver alone.

Scientists learned to produce an incredibly bright X-ray source by zapping a ring of tiny wires with a huge current. This donut of wires is vaporized in an instant forming a plasma donut that collapses on itself. The resulting flash is as bright as a nuclear weapon's X-ray pulse and thus useful for lab studies, and practical effects testing. The huge magnetic fields generated by the plasma and it's subsequent collapse are also useful in their own right.

Sandia has driven a tiny flyer plate to over 30Km/Sec, which would be faster than escape velocity from earth ( ignoring aerodynamic effects that would tear the plate up if launched in air at the ground.....) for use in material property testing experiments. Sandia scientists have been able to tailor the acceleration so that the material stays intact long enough to do experiments on the properties of various materials at a high degree of pressure.

The X-rays generated by the Z process can be harnessed in a tiny gold cylinder configured as a hohlraum, a cavity where the surfaces are heated by the X-rays, and surround a capsule target that may contain fusion fuel such as deuterium. The uniform bath of X-rays evaporates the surface of the capsule and the ablated material rockets the remaining material into a pinpoint of highly compressed material.

Utilizing the pettawatt laser technology developed at Lawrence Livermore Labs, the "Z" machine will be able to zap the compressed pellets with a "spark" that may ignite fusion, producing the elusive "star in the lab".

While I appreciate the many tricky physics issues remaining, it's clear that the progress made since 1995 is huge, and that the program could produce a working device soon if supported with a sufficient budget and staffed with enough bright scientists and engineers. This program should be pushed and supported by our government, indeed by the world community and not forced to compete with magnetic fusion and laser fusion programs, simply on the merits of the case, and because it is too soon to tell which approach will be the most useful.

I think that given the geopolitical situation, it is wise for a nation to persue the sort of energy system that could free us from dependency on oil, that could power our flight to the planets, that could help us to understand the high energy densityphysics.

These exciting developments are mostly shielded from public view behind a secret curtain, parted now and then as either scientific developments are published ( thanks to the American Instutite of Physics), or as the developers seek funding. The military applications are driving the funding at this point, though I believe that our nation would benefit from a much broader and better financed program. There are certainly proliferation concerns, but it's a very technically difficult process and unlikely to be attractive to the sort of folks who want instant political power so any concerns are way down the line from a practical point of view.

The Bush administration should immediately increase support for this area of research, broadening the work from NRL and Sandia to include various university programs, and to train the next generation of scientists, engineers, and technicians in this vital area.

Friday, July 01, 2005

The recent disclosure that the Veterans Administration budget requests have not recognized the 80,000 new patients in the system from the Afganistan and Iraq wars and thus are some 3 Billion per year low, is shameful from an administration that professes respect for our men and women in Uniform who sacrifice so much for our country. The Congress should immediately demand the firing of the VA top official, and should increase the budget authorization, and require that the VA immediately take steps to address the special needs of this war.

The Bush administration doesn't want to admit the toll we pay for this foreign policy, but that is of no account to me. Our government having made the decision to go to war must also prepare for the inevitable effects of war. Nevermind the cheerleading shouts about how easy it will be, the propaganda about how our system can handle it without challenges.

The reality is that the 1800 killed are the tip of the mountain, with some 20000 serious disabilities, four times that number who are VA patients from these wars. We need to invest in treatment for psychological trauma, for rehab, and for the many more who will surely need this care as the war evolves over the next decade.

It's one more cost that was hidden in the effort to mislead the public about the real costs of this war here at home. Naturally we also know that the Iraqi people are bearning a cost that is many times these numbers, and their medical and rehab infrastructure is less sophisticated, plus they have public health challenges absent from the VA situation.

Our nation owes this care nomatter what the propaganda cost. Keeping our social contract is expensive, but it also keeps us able to recruit and retain our forces, and it surely helps our society as we embrace returned injured and handicapped soldiers. You judge a democracy largely by how it treats it's most vulnerable. Here we see clearly how our society feels about the sacrifices made in our name.

At this point there are thankfully a few who stand up for our vets, and I hope that the Congress can come together to bring the needed resources to bear, to openly admit the need, and to commit to increase the capacity of the system to ensure that we care for our own. This would restore some integrity and balance to our national conversation about how we will conduct this war, how we prepare for peace.

Thursday, February 24, 2005

On the more speculative side, recent research shows that it may be possible to accelerate an electron beam from say 5 mev or 10 mev up to a GEV using a petawatt class laser and wakefield acceleration schemes. I'd like to see a way to produce GEV protons, as these make muons easily, and muons catalyze fusion in certain arrangements.

While the LWFA (Laser Wake Field Accelerator) approach hasn't yet delivered muon capable proton beams, it does seem within reach now that petawatt lasers are reaching the 10s of joules level, and with the recent work, it appears that multistage systems are possible.

THis would potentially enable us to build systems using muons as the "spark" to bootstrap a small fusion power system without the hybrid approaches now necessary. Potentially we could also avoid most of the tritium inventory, and use material systems that would have a minimum of activation over the life of the equipment, vastly reducing the hazardous waste problems that plague present nuclear power systems.

Seems as if we are still a ways off since most research today is driving the basic technology, and applications are quite a ways off. Unfortunately I don't have enough background to know how much energy it takes to produce muons from electrons directly, but I do know it is straightforward given Gev protons, they produce pions, pi- decays into muons, they can be collected.

Who knows, if Dave Jackson is still interested, he's probably already thought of this approach....

Saturday, January 29, 2005

The potential benefits of a fusion power system are great, though it seems likely that we will see hybrid fusion-fission systems first, and they have safety considerations that are serious. Yet with greenhouse warming fast becomming the most important threat to humanity, developing options independent of fossil fuels is vital. Accordingly, the fusion technology programs that have been put on hold or scaled down should instead be ramped up, and we ought to divert a billion or so from the Iraq War to push fast ignition research, z-pinch, and applications development.

In the U.S. the environmental movement hasn't yet incorporated the new logic of combating global warming, a new logic that will drive some policy shifts, require some new thinking from the leaders if they are to remain relevant.

We must also develop the renewable energy systems, but it's too early to rule out the fusion option just because there are some thorny operational safety issues. Tritium handling comes into play in most fusion cycle plants, and tritium is tricky to handle. Tritium safety is a topic that has been studied and practiced for decades, so there is quite a large body of knowledge to work with. These plants will introduce some new chemical hazards, pressure regimes not seen before such as the cycling as pellets are "burned", liquid lithium blankets, and the need to control the proliferation potential at plant sites.

Never the less, these systems can also breed fuel for the existing fission cycle plants, or better, for third generation fission cycle plants using sub critical assemblies that are only driven to criticality by the fusion burns. The inherrent citicality safety of such power plants was the topic of a talk by a nobel prize winning CERN scientist some years ago at UC Berkeley. He advocated thorium fission power, using a 55 gallon drum sized "core" assembly along with an accelerator beam that brought it to the power production level.

These fusion neutrons are mostly 17 kev to start, definately "fast" neutrons ---- :-)

Following this draft, I came on a very recent paper in Phisics Letters "A" by F. Winterberg that talks about hybrid fusion-fission-fusion using his favorite device, the dense plasma focus....of course. FW has a distaste for lasers, seems to go a bit light on the math in his paper, nevertheless, it confirms my post above ( drafted prior to his article being published), and does give some idea of the design. Clearly with a bit of extrapolation, my idea of a laser initiated DPF system would also go, and likely with less tricky stuff than FW's system. He doesn't get much of a following by the folks with the money for some reason, but his papers point at a simple way to get lots of neutrons.

Combine his approach with the Carlos Rubbia ideas, and it's clear that one could bootstrap with just a bit of laser created dt fuel into a full fuel cycle.

interesting.

Thursday, January 13, 2005

Recent news from Osaka, Japan published by the scientists and engineers at ILE states that they now are confident that fast ignition of a fusion burn by a petawatt laser coupled with the existing multibeam laser compression systems "is understood".

Simple in concept, the system is capable of taking a plastic pellet containing dt and once compressed by the main lasers, hits it with a petawatt pulse that generates a burst of high energy electrons and ions that interacts with the compressed pellet and initiates fusion reactions.

The exciting thing reported by the researchers is that when they tried this experiment, when they synchronized the petawatt beam with maximum compression, they generated a burst of neutrons indicating that the petawatt beam does indeed boost the compressed target into the fusion regime.

One would think that our government would at least want to keep the US in the forefront of such potentially world order changing research, but the reality is that our effort has been cut back, the money throttled down, and thus the U.S. isn't moving as fast as possible to understand and ultimately to exploit this new technology.

One thing that governments don't always consider is that this generation of scientists has a limited time working at maximum productivity before the biological limitations set in. It takes so many years to master the math, physics, technology and so on that unless we really push them once they start to be scientifically productive, we don't get the full benefit of their intuition.

When the experiments take years to develop on machines that cost billions, the limitations are both "understandable" and stupid. This technology has the potential to help with shifting energy production away from greenhouse producing fossil fuels, to enable us to develop new space propulsion systems capable of vastly improving our planetary exploration, using simple materials plentiful on earth. This technology could also extend the life of our conventional fission power systems by hundreds of years.

Since our civilization has only a limited time to develop energy sources that don't screw-up the environment on a global scale, it is important to push this "fast igniter" effort as fast as possible.
I hope that we can perhaps find someone in a position to nudge the budget folks to enable the US to help the worldwide effort to bring this idea to blossom. It might be the most important tiny nudge in resources possible at this time.