Anxiety

The shift in the climate is a big threat to our civilization, and it's clear that some parts of our government are seriously thinking about the implications despite the President's denials that climate change is real. The military has conducted research, NASA has a big effort underway, and the National lab system is working on aspects of this though much of that work is evidently not in the public domain. Big banks and insurance companies are interested, as well as agencies like California's water management organizations.

Since it's evident that climate shifts are occuring, and that the velocity of change is perhaps faster than most of us imagined, we are headded into a time of significant history as if in a fog.

While it appears as if there will be mass extinctions, huge deserts emerging and shrinking water resources in mountain area's, opportunities will also emerge in the short term at least. No doubt the emergence of huge weather systems with wind and rain intensity that exceeds our present experience will produce events that challenge our ability to cope especially in third world countries, events that will for the first time exceed the ability of our "first world" countries to cope.

There have been some apocalyptic movies that warn of the consequences of a large storm in a city like New York, but they really don't convey the disruption to society that would occur if such an event hits in the next 50 years. Perhaps the government simply can't figure what to do and doesn't want to freak out the population, perhaps the senior leaders know that the forces that are unleashed are beyond our control.

It seems as if China and India are developing at a rate where the environmental consequences will compound at the critical point in the evolution of the CO2 and greenhouse gas build up, and that human greed is an unstoppable force. We seem to have the collective intellegence of yeast, awating the build up of "fermentation byproducts" ( in this case greenhouse gases) that will bring our population into balance with the global carrying capacity.

Unfortunately the loss of the species that have developed over the past 250 million years will make this a bleak place for our descendents unless we rapidly plan for how to preserve the genetic information, and learn enough to adapt and build a modern "noah's ark" to help the species move into the future, to enable human civilization to evolve into a form that can live sustainabily.

There seems to be an emerging consensus that this challenge is real, that we face an imperitive although some like Dr. Lovelock think it may be too late. Even if it is too late for many, there is nothing else to do but respond as best as we can, and we owe it to our descendents and fellow beings to work on the problem while we are here.

Facinating to see the historical sweep of the development of our understanding of climate change caused by our civilization as the consciousness emerges. We have a considerable collective intellegence and perhaps can shape the evolution of the shift in some less harmful ways. Certainly the development of sustainable energy technologies will spawn new industries, the use of climate models allows us to consider mitigation strategies, predict effects of the evolving weather patterns, and devise responses to the ecological shifts that are now inevitable.

One thing that is also clear is that there will be intense competition for natural resources as the basic hydrology changes, as sea level rises and as land suitable for farming shifts due to desertification, climate changes and so on. The good news is that given time, human civilization is quite adaptable and that politics will be shaped by the natural system changes.

I'm optimistic that enclaves will develop where the knowledge of how to live in our new world will be preserved for our descendents, but anxious for my future, for my family and my community. Looking at the map showing sea level rise, my home is right on the shore of the 2075 bay.........and likely I'll be gone by then. How much should we/can we do now?

Clearly the preservation of species is key, learning how to husband whole ecosystems and to help them to move and find new geographical niches would be a gift to our descendents that would keep on giving for thousands of years. This opportunity is unique in history and I hope we are able to embrace it.

Bruce Bagnoli

Physics for fun

Laser generated proton beam or ion beam fast ignition is an idea that I've thought about for some time. Recently, when I discovered a paper in a the December 2006 journal Physics of Plasmas by a Bolivian physicist ( Phys. Plasmas 13, 122704 Fast ignition of a compressed inertial confinement fusion hemispherical capsule by two proton beams by Mauro Temporal ) I was excited to learn what he designed.

His idea is elegant, with the two beams generated by the same cone from targets located at different distances from the point of the same cone, doing two different tasks. One makes the spark, the other does isochoric heating/shock wave generation.

Temporal proposes that a variation on the Japanese cone in capsule method be used, though his variation uses a hemispherical capsule compared with the original Osaka design using a spherical capsule with a cone inserted into the center that channels the beam. ( see for example : M. Tabak et al, Phys Plasmas 1, 1626 (1994) or R.Kodama, T Yamanaka et al, Nature (London) 412,798(2001) :: R. Kodama, T. Yamanaka et al, Nucl.Fusion 44, s276 (2004) and so on.

My idea is to use two colliding beams that meet in the capsule to ignite the burn using conventional laser hohlraum compression, with the proton beams produced by petawatt lasers in the same chain as the compression lasers to ensure correct timing. I suggest that two cones be used, and that the capsule be prolate. Alternately one could employ the colliding beam approach with a Z-pinch for a higher yield.

My idea takes advantage of the fact that colliding beams generate a higher energy though higher energy particles may also escape the assembled system in higher fraction. Using higher Z ions would allow the bragg peak to deposit energy in the right place more precisely though things rapidly get complicated using such schemes.

My two colliding beam design may trigger the burn with a simple geometry and be applicable to z-pinch systems as well. In the Z-pinch system my device design would potentially ignite a larger fraction of the material and use the energy very efficiently.

Anyway, its fun thinking about the dynamics of these tiny energy sources and to explore the concepts even without access to the experimental facilities that would test ideas and expose the many flaws in our designs. As Klaus Berkner (LBL) said " experimentalists keep the theorists from drifting away....". Since I’m not limited by the real known physics, I can dream up science fiction devices that work in my mind but may never work in our world. I can gloss over real issues like RT or M instabilities, or perhaps I can find solutions that work, who knows?


It is wonderful to see Temporal’s original thought process, as most of the thoughts and current developments by the main labs are necessarily obscured from those of us outside the main efforts and seldom see the light of publication in the open journals.

A Bolivian physicist, who knows if his ideas will ever be tested or will work, but the same can be said for my ideas as well. The Andes have produced some great physicists including Peruvian Pier Oddone ( now at Fermi lab I think).

Fun with numbers.

Bruce Bagnoli