Fukushima is the new Mayan prophecy

Maya predicted the apocalypse on 21st December 2012. The world survived so there is a need for a substitute. The Fukushima Daiichi Nuclear Power Plant seems a good candidate to many bloggers and YouTube channels (I won’t link them).

Fukushima_I_by_Digital_Globe_2

There is a raising concern on the web about the situation at the crippled Japanese nuclear power plant. There are claims about the possibility that the ecosystem of the Pacific Ocean will be destroyed. Some sources even describe the Fukushima disaster as an Extinction Event for humanity. Obviously these are ridiculous exaggerations, anyway many people seem very concerned about this, especially US people. As always happens, the lack of interest of the mainstream media is explained as an attempt of the Governments of the world to conceal the situation.
Usually there is something missing in these alarmist posts: the numbers. I will show few numbers to explain why the Fukushima disaster is a real disaster on a local scale, but has negligible effects on a global scale.

Fukushima released a huge amount of radioactivity into the environment, no doubt about this. In these kind of nuclear accidents there are two isotopes that are the main health concern since they are volatile:

  • I-131 is the main concern immediately after a nuclear accident as it can cause thyroid cancer. Its half-life is about 8 days.
  • Cs-137 (together with Cs-134) is the main radioactivity source after few months. Its half life is 30 years so it is a long-term environmental issue. It is the main responsible for the current radioactivity around Chernobyl and it is a nasty gamma emitter.

I want to talk mainly about Cs-137, as any alleged long-term effect caused by Fukushima should be caused by this isotope. Well, Fukushima released up to 77PBq of Cs-137, i.e. 24kg of Cs-137. If the discharged material will be spread homogeneously in the Pacific Ocean, the average concentration will be 0.11 Bq/m3. However, seawater already contains radioactive isotopes:

  • Uranium: 33 Bq/m3
  • Potassium-40: 11000 Bq/m3
  • Tritium: 600 Bq/m3
  • Carbon-14: 5 Bq/m3
  • Rubidium-87: 1100 Bq/m3

Now, it’s true that using Bq to compare radioisotopes is naive, so let’s check the Cs-137 limit for drinkable water of the EPA (Environment Protection Agency) that is far lower than the one of the FDA (Food and Drug Administration) : 3 pCi/l or 111Bq/m3.
This means that the Cs-137 contamination will be 1000 times lower than the EPA limit for drinkable water!
You can say then that cesium could bio-accumulate like mercury, so since we are at the top of the food chain, we risk to ingest a huge dose of Cs-137 when we eat fish. I don’t know if cesium can bio-accumulate, but I can show you that there won’t be any risk anyway.

In the Pacific Ocean there are about 200 million tons of “normal” cesium, Cs-133. If the discharged material will be spread homogeneously, we will have that for every 8.3 billion atoms of Cs-133 there is 1 atom of Cs-137. Now, biological processes don’t make isotopic differentiation, it means that you won’t have changes in the ratio Cs-137/Cs-133, unless there is some strange fish with some enrichment centrifuge in its body. In general a chemical element can bio-accumulate, but the ratio between isotopes is constant in biological processes.

We can conservatively assume that we eat a lot of fish from Pacific Ocean, and that the ratio Cs-137/Cs-133 in our body will be equal the one of the fishes in the Pacific Ocean. A man that with a body mass of 70kg has about 1.5mg of cesium in his body. If for every 8.3 billion atoms of Cs-133 there is one radioactive atom of Cs-137, then the man will have 1.8·10-13g of Cs-137 in his body, that is 0.58Bq. Doing some conservative calculations (Weighting factors=20, decay energy=1.2MeV) he will have an exposure of 1 μSv/year from Cs-137, while the natural background radiation is at least 2000 μSv/year. Not a problem at all. It’s like 12 banana equivalent doses, or 12 minutes on a commercial flight.

Obviously all my arguments rely on the fact that the Cs-137 will be distributed equally across the Pacific Ocean. Health, biological and environmental issues can still arise where the ratio Cs-137/Cs-133 is at least 1000 times higher, probably close to the Japanese coast.
I think it’s obvious that the global environmental consequences of the Fukushima accident are totally negligible. Clearly it’s a local disaster, sadly we will see a statistical increase in thyroid cancer cases, especially in kids. Even if the survival rate of radiation induced thyroid cancer is estimated to be about 99% from Chernobyl experience, this will be a nasty consequence. Let’s however not to forget that this accident is part of a bigger catastrophic event that buried 18000 people in the mud.

I will write again about other scary claims made by all these bloggers, like the alleged effects of the radiation on the sea-life in California and the convenient comparison between Fukushima and Hiroshima.

In conclusion: I am not saying you should trust the Governments or TEPCO, I am saying that the best way to develop an informed opinion is gather all the data and do the calculation by yourself.

Links:

http://www.physics.isu.edu/radinf/natural.htm
http://www.seafriends.org.nz/oceano/seawater.htm
http://www.forbes.com/sites/jeffmcmahon/2011/04/14/why-does-fda-tolerate-more-radiation-than-epa/
http://water.epa.gov/drink/contaminants/
http://en.wikipedia.org/wiki/Composition_of_the_human_body
http://en.wikipedia.org/wiki/Caesium-137
http://en.wikipedia.org/wiki/Background_radiation
http://en.wikipedia.org/wiki/2011_Tohoku_earthquake_and_tsunami

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Posted in Economics, Energy | Tagged , , , | Leave a comment

Is bitcoin mining a waste of energy and resources?

Spending energy to secure and operate a payment system is hardly a waste” is the anwer on bitcoin.org.

Fine, but traditional currencies don’t need proof-of-work.

I totally agree that Proof-of-work (i.e. doing a lot of computation to validate transactions) is necessary for a non-centralized cryptocurrency, I don’t question this. However, I think that one of the goals of technology innovation is reducing the resources required to perform the same task. Now, are bitcoins really more efficient than traditional currencies?

Mining reward can be considered a cost to make the bitcoin network working properly. During 2013, 12% of Bitcoins have been generated for covering those costs. That’s a lot! It’s like if the Federal Reserve printed 12 cents per year for every dollar you have in your pocket or your bank account, just to process the transactions. The Fed does print money, but mainly for financing the US government, that is a total different thing.

This inflation (intended ad increase of money supply, obviously not as price increase) will decrease, but it will be anyway 3.7% in 2020. So if the Bitcoin capitalisation will be 1000 G$ in 2020, at least 37G$ will be spent to process the transactions, without taking the fees into account. These costs can’t be avoided, as they need to be a good incentive for everybody to mine and to find new blocks. If those costs were very low, a 51% attack could be possible, so we will ever have medium-high costs associated to the bitcoin network. And a very high energy bill.

It looks to me that this argumentation has been rapidly confuted saying that with traditional currency you have banks, armored vehicles, security costs, cash management, etc…

But very different things are mixed together:

  1. Cash management
  2. Financial services
  3. IT security

Cash management. Any form of electronic payment (in any currency) can help to reduce the costs associated to cash management. So with bitcoin you won’t have any armored vehicle, neither with other traditional electronic payment. This is an advantage of bitcoins over cash, but not over credit/debit cards and any other existing electronic payment method.

Financial services. Banks, financial institutions will continue to work with any currency. They basically borrow and lend money. If everybody will use bitcoins, we will have anyway banks that offer bitcoin credit cards, bitcoin mortgages, bitcoin investment products. Bitcoins won’t get rid of the financial industry. Not at all. People will continue to lend and to borrow money, no matter the currency is.

IT security: this is a critical issue with both bitcoins and traditional currencies. We saw several bitcoin heists, probably due to badly designed IT solutions. I could say for bitcoins IT security is even more critical since bitcoins are unrecoverable if they are stolen/lost.

So, I am not convinced about the sustainability of a system that, if massively adopted, will require probably tens of GW worldwide and hundreds/thousands of server farms around the world that calculate hashes, nothing really useful.

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Is a communication with God possible?

In this post I want to define a communication protocol with God.
First of all, what God is? I am not talking only about the God of the most diffused monotheistic religions, I am looking for any possible deity. So, let’s clarify what I mean for “God”:

  • God is an intelligent entity, let’s say at least as intelligent as a human.
  • God observes the universe. He can just observe how the galaxies are distributed or the evolution of the universe, or he can see the details, even living organisms on a planet. He can even go down to subatomic scale. Also, He can be able to observe the whole universe simultaneously, or maybe he can only focus on a small part of it at the same time.
  • God can affect the universe (otherwise it would be non-existent by definition). Obviously, there are different degrees on how He can interact with the universe. In example, if He can only create 1 neutrino every year across the universe, any communication will be extremely unlikely and horribly difficult, even with the best effort from both parties

The following table should give some examples about the characteristic of a deity.

God_Table

So, once defined what God is, let’s define the communication protocol:

<I write the protocol>
<God reads the protocol>
loop
   <I write the request, the number of expected bits (N) and their meaning>
   for i=1 to N
      <I perform the experiment>
      <God affects the outcome of the experiment to send the bit>
   end for
   <I check the validity of the answer (e.g. a check-sum must match)>
   If (<The answer is not valid (e.g. God is not communicating)> and 
       <I don't want to waste any more time>) or
      <I have nothing else to ask> then
      exit
   end if
end loop

In order to have a reliable communication channel, the following conditions must be met:

  • God is intelligent enough to understand the protocol. Human-like intelligence is enough.
  • God must observe my protocol, e.g. displayed on my/your monitor or idealized somehow in my brain.
  • God must be able to affect the outcome of the experiment.
  • God must be willing to communicate with me.

About the experiment, I can think about some options:

  1. I can use a Geiger counter (like this “Telephone-To-God“) and I can ask God to increase the number of detected decays over a certain number in the next 5 seconds, if He wants to transmit an ‘1’. It should be an easy task for God, but not for me: I would have to spend money for the Geiger counter.
  2. I can use a true random generator running on my computer. In this case God must affect the entropy sources of the computer in a way that the hash function will return the desired value. This will require a tremendous amount of computation for God, and He could be unable to answer.
  3. I can pick a card from a deck. God must drive my choice, affecting my neural processes. It could be easier than the previous method.

Just to clarify, the God of the main monotheistic religions should have all those requirements, so if the experiment will be unsuccessful it should mean that He doesn’t exist or He doesn’t want to communicate with me.

I will try the 2nd and the 3rd method and I will let you know. One day maybe I will try with the Geiger counter too.

Posted in Philosophy | Leave a comment

The renewable/nuclear “Energy Bridge”

When I come across an article about the future of energy, I always read that the renewable energies will be the long-term solution and fossil fuels are just the present. The nuclear energy is even described as a dying technology. I think the main facts are actually:

  • Nuclear fusion has all the key elements of an optimal long-term solution (sustainable, clean, renewable). The only single (obvious) objections is that it won’t be available for the next 40 years. Moreover, the construction of hundreds of fusion power plants across the world won’t be a sudden process.
  • Fossil fuels will last for many decades. This Wikipedia graph [link] shows the reserves vs production ratio. It’s interesting to note that it has increased in the last 30 years. The ratio was only 27 years in 1980, it means that at that time, a massive decrease in oil production was expected by 2010. In fact oil production has increased from 75 to 87 million barrels per day, and the ratio is now 46 years. For gas it’s quite similar, for coal the availability is even bigger. The total proven energy resources of fossil fuels are 36ZJ, equivalent to 65 years of consumption at current levels.
  • Fossil fuels contribute to the climate change. How much much each ton of CO2 will impact on the global temperature is not easy to predict, however we can’t afford to increase much more the burning of fossil fuels from the current level.
  • Renewable energies and fission-nuclear (traditional and IV generation) are the only energy sources that doesn’t involve CO2 emission and that are available now and in the next decades. A huge improvement is expected but there are several downsides for each source. I will write many articles on renewable and nuclear sources, since I see many misconceptions around them (like bio-fuels, that I consider a completely non-sustainable energy source).
  • Energy demand will increase for many reasons. I will write posts also on this specific subject. The developing countries will need more energy than today. Moreover, computational applications (AI, simulations, data processing) will require more and more energy as their application scope will increase constantly.

Given those assumptions, renewable and nuclear (fission) energy sources can be considered a bridge that will allow us to survive until a solution (i.e. nuclear fusion) will come up, without changing in a dramatic way the global climate. The following graph is just an example about what I consider a likely scenario

Energy_outlook

Fossil fuels production/consumption will be very stable for decades, renewable sources will sustain the energy demand increase, then nuclear fusion will quickly substitute the other energy sources, creating a dramatic change in the energy market. It will probably be an energy singularity (maybe even connected with the technological singularity).

Finally, as everyone I think it’s very important to invest in R&D of renewable/nuclear energy sources, but we must bear in mind that we are talking about a 40-70 years mission. This must be taken into account, especially when we will need to decide whether we must invest decades and G$ in the development of some technologies, like Thorium reactors, or not.

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Technological singularity

I have always thought that one day AI agents will be able to improve themselves and to make new technological discoveries on their own, triggering a sort of chain reaction. Now I realize that there is a name for this: Technological Singularity. Shame on me that I didn’t know the term.
The main fact about this are:

  • In very few decades we will have the computational power needed to simulate an our brain. Simulating the human brain at neural level should require about 1 EFlop/s (http://en.wikipedia.org/wiki/Artificial_brain). Now the most powerful supercomputer is 0.034 EFlop/s (http://www.top500.org/lists/2013/11/). The trend of the last 8 years suggests a performance doubling every 12 months, even more than the Moore’s law. This means that we will be able to simulate an human brain by 2020 and an industrial facility will simulate 1000 human brains (equivalent to an R&D department) by 2025-2030. That could trigger the singularity.
  • There is a lack of theoretical background about how an algorithm can achieve consciousness and efficient learning. Simulate the human brain could be the most naive solution, however it’s notoriously difficult to understand and to mimic all the parts of the human brain. Maybe it couldn’t be the most efficient way to get an “human-like” computer. Or maybe the simulation will miss some key feature. However, AI is giving amazing results in image recognition, speech analysis and in solving many problem classes. I suspect that the computational power is the real limiting factor.
  • There is some concern about the danger of a very smart computer. It could (and must) try to gain power in order to achieve its goals, whatever they are.

About the scenario before/during/after a singularity, I have thought about the following ones:

  • Control. We control all the AI agents, even controlling the development of new AI facility to check if they are prone to become dangerous. In a similar way today the enrichment of Uranium is monitored at a very high international level. Anyway it couldn’t last forever. How to control an AI that is billion times smarter than an human? And we know how to deals with humans, what if this AI behaves and reasons in a very different way?
  • Transhumanism. Transform ourselves in computers through some process of mind uploading before the AI could wipe out the humanity. With mind uploading we turn (even gradually) our neuron based mind to a software-based mind. This is definitely an amazing scenario. We would be (almost) immortal, could travel space, have huge knowledge, have very intense relationship with other minds, and so on. The transition could create anyway ethical issues: what if the humans that have completed the upload decides to (easily) turn against the people that are still “normal humans” and so very vulnerable?
  • Coexistence. We need to find a way to convince the AI agent(s) that it would be better to cooperate with us. We would need to have a technological power similar to the AI agents, maybe we need to domesticate some powerful AI agent. We could require a mutual assured destruction scheme, or we could trade our survival with some resource valuable to the AI that can’t be get without our approval. In example we can make the AI curious about some information we have (like a person addicted to a TV series) and then we can provide these information in order to guarantee our survival.
  • Submission. The AI takes control of the planet, but for some reason doesn’t want to kill us. It’s similar to coexistence but not based on an agreement. The AI just wants to keep us alive. It is a similar reason we try to protect endangered animals too. We are “curious” or interested to see the animals living in their environment so we don’t want to lose them, and we don’t consider them a threat. I don’t think we will be enslaved, the AI won’t need our work-force. For sure it will want to keep us from being a threat so it will exercise a certain control on our industrial activities. But maybe it could give us the opportunity to have a pleasant life.
  • Extermination (Terminator-like). Does the fact that it has been exploited by sci-fi movies make it implausible?
  • Torture. Worst-case scenario. It’s like the submission scenario but, for some reason, the AI agent enjoys make us suffering. It’s very unlikely and it doesn’t make much sense, but how can we know what a so powerful AI mind thinks? I guess the fear of this scenario can affect future political decision about how to handle the Singularity.

Let’s see what happens…

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