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Cosmic Variance

Tuesday, January 31, 2006

Clifford Talking About Big Oil Profit

I encouraneg ever one to read the "Twilight in the Desert", a must read book by an authoritative figure in the industry, Matthew Simmons. Also see Princeton professor Kenneth Deffeyes. He predicted the world wide petroleum production peak around Thanksgiving 2005 and sticked to his prediction. I believe he was wrong by a year or so. The actual peak occured in April of 2004. We were not able to see a production per day as high as the April 2004 figure.

Much worse than oil is the situation of natural gas. While you see gasoline price going from $1.50 to $3.00, the natural price has actually gone from $2 to a peak of $17 right before Christmass 2005. (The price is measured per thousand cubic feet). Just one year ago it was still no more than $7.

Most people have the perception that as long as there is oil underground, we can pump it out at any production speed we want, until last drop is drawn, and then it suddenly stops. That is not the case! Due to geological reasons oil can only be pumped out at no faster than a certain speed, or the oil field will collapse and not produce any more. Therefore, even though there is still one half oil stored underground, the daily production rate has peaked and can not go up any further, and it will decline year by year. That's the Peak Oil phenomena. The majority of oil production countries have seen their production peaked and then enter an ever declining phase, including the USA. Sandi is the only major oil producer which has not yet officially peaked, but people speculate that it indeed has.

A big question looms that as it becomes ever more clear that the world's oil is becoming depleted, is there any reason to believe that oil producing nations will not at some point decide to "go slow" and leave some for their future generations, instead of continuously pumping it at all speed and sell it cheap to other nations? If OPEC countries decide to hold back their oil in this fashion, it's going to be a world wide chaos. But I see no reason why oil producers will not do it, it just seem so logical!

Thursday, January 26, 2006

The ICE-CUBE experiment on the Southern Pole

Lubos on his blog meantioned this ICE CUBE experiment.

Sounds an interesting experiment. But what does it has to do with string theory? You have not shown us you can predict exactly how many down-going or up-going high energy neutrinos you can expect to detect, based on string theory calculation. String theory can't say anything about interaction cross-sections or reaction rates so it's out of the equation.

I am highly skeptical that they can obtain significant event counts to produce statistically meaningful result. If you read the 4 page paper carefully, you find that the author is trying desperately to STRETCH THE NUMBER to un-reasonable limit, in order to produce a reasonably looking event count.

According to the author, during a total of 15 years of experiment run (a very long time, isn't it?), he expects to detect mere 4 down going neutrino events and 20 up going events. Very small number and hardly enough to do any statistics, you would agree.

But even that (4,20) event count estimate is way too much optimistic. If you carefully exam his calculation, you find he stretched the numbers too much. A more realistic estimate would give you an event count 100 times lower. Rendering the experiment meaningless since your expectation of event count is less than ONE.

First big mistake the author made, is he used the effective aperture of individual detectors times the length of detector strings to estimate the number of target nucleons, thus attrived at NT = 6x10^38. That estimate is wrong because there is redundancy between detectors.

A more common sense estimate is actually calculate how many atoms are involves in the detection. This brochure says the total volume of ice in the IceCube is ONE CUBIC KILOMETER. One should be able to calculate how many nucleons is contained in one cubic kilometer of ice.

The density of ice is about 900 kilogram per cubic meter. So one cubic ice is 9x10^11 kilogram. The water molecule contains 3 nucleons, and has an atomic weight of 18. That means each 0.018 kilogram contains 3 times the Avogardro constant, 6x10^23 nucleons. Put those number together. The total number of target nucleons is 9x10^37.

The author used 6x10^38 nucleons, which is an over estimate of 7 times already.

The author also grossly over estimated the detection efficiency to be between 50% to 100%. No such efficiency exists. Think about it, one single muon is created a few hundred meters away, it does emit some number of photons, but for the photons to be almost 100% detectable by a detector a few hundred meters away, that is really a stretch. It takes many many many photos to trigger an event. During dark nights there are still billions of bilions of photons entering our eyes per second but we hardly see anything. I do not know how to calculate the quantum efficiency but it must be way below 100%.

Now the technical difficulties how you can run such an experiment for 15 years in the frigid cold in the southern pole? These detectors and instruments must run on continuous electricity. How do you supply stable electricity for 15 years? Using solar panels? Well half of the year on the southern pole will be permanent darkness without sun shine. So no solar energy.

You may think of batteries. But the temperature is so cold that the fluid of the batteries will freeze into solid, disabling the battery. If you read recent news about the cold snip in Russian, you know many people had to take their car batteries into their home to keep it warm over night and put it back on the car the next morning. Any one not bringing their battery home will not have a working car the next day. So battery option is out for the souther pole experiment due to the temperature.

Or some device burning gasoline to generate electric power? That would be subject to supply issues and human maintenence. And it is impossible to maintain it year around.

Anyway you look at it, the experiment simply can not be run continuously year around. You may be able to run some months during each year, but not all the time.

The author used a full 15 years to estimate the event count. Again that is a gross over estimate. The realistic number should probably be divided by 3 or 4.

After you factor in all these realistic consideration, I am sure the experiment simply will not produce enough event count to draw any statistically meaningful result of any kind.

Wednesday, January 25, 2006

Idiots at the other Cosmic Variance

Mark Troden at the other Cosmic Variance talked about a so called recent discovery of an earth like planet 25,000 light years away. The discovery was made using the gravitational lensing effect of the General Relativity.

I say it's totally nonsense. And too bad that cosmologists like Mark Troden et al spend a lifetime studying General Relativity, but could not carry out a little bit order of magnitude estimation and and see through it that the observed brightening effect actually has NOTHING to do with gravitational lensing.

I am not saying gravitational lensing does not exist. But what the research group observed could not be explained as gravitational lensing.

If there is a gravitational lensing, you can imagine the gravitational field acts like an optical lense. The diameter of that lense is about the distance where the gravity is significant, i.e., approximately some multiples of the diameter of the object that causes the gravitational lensing. What about the focus length? We know star lights are bended approximately 1 arcsecond when it skip over the surface of the sun. So the focal length would be approximately the diameter divided by the sine of that bending angle, i.e., about 2x10^5 times the diameter of the lense. The star is about the same size as the sun, so its diameter is 2x10^9 meter, multiply by let say 5 times, 1x10^10, that's about how big the diameter of the lense is. So the focal length of the gravitational lense would be about 2x10^15 meter, or, 0.2 light years distance at most.

The distance of the observed object is 25,000 light years away, more than 1x10^5 times longer than the possible focal length of the gravitational lense. Clearly, had it been a gravitational lense, you would only observe the star to be dimmer, not brighter, because the light is diverged by the lense. You would have to be at a distance of approximately the correct focal length, to be able to see the light more concentrated and hence see the star become brighter.

And not to meantion that the gravitational lense of that planet would have to be of much smaller size. Consider that the observer, the earth is moving at 30km per second speed around the sun. The time that this planet sits right in the path of the light would last a much shorter time period, probably a few minutes, instead of half a day as reported. Also, the chance that the planet happen to be sitting at exactly the right place to block the star light to earth, would be so small that you are unlikely to see the lensing effect.

I challenge Mark Troden or Sean to use his knowledge of GR, to do a more careful quantitative estimate of exactly how big the lensing effect would be, and what the focal length would be like, therefore to rule in or rule out that reported observation as gravitational lensing.

Cosmic Variance

Friday, January 06, 2006

LuboŇ° Motl: Second or third warmest year#links

Lubos Motl on his blog talks about
2005: second or third warmest year#links

This guy clearly has not the slightest idea about statistics. He talked about the Brownian Movement as a statistical model to describe temperature fluctuations. That's completely wrong. Temperatures fluctuate around an average level, but Brownian Movements do not circulate around a central location. Given sufficient time, a particle doing Brownian Movements can drift away from its original place an arbitrarily long distance away. That is not the case for temperature.

Lubos immediately erased my comment after I pointing out his mistake, therefore embarrassing him. This poor young man. He still doesn't get why he was wrong!

Wednesday, January 04, 2006

The LHC Will Be a Stillborn

Mark at the CosmicVariance.com just wrote about the LHC, as it was reported by BBC. So I am going to say a few things.

My prediction is nothing will come out of LHC. It will be a still birth. I based my prediction on information revealed by this article, which was first meantioned by Lubos. What did the article say? It said that they were planning to shut the LHC down for half of the year and operate only half of the year to save electricity cost.

In view that despite of the huge cost overrun during the construction of LHC, member states REFUSED to increase the budget and CERN had to cut corners some where else and borrow money through 2010 to get the machine built. And in view that a global energy crisis is looming. My conclusions is by the time LHC is finished, the electricity price will be so high that CERN simply do not have the budget to pay electricity bill to run the machine. Mean while, do not expect any budget increase from member states. The top priority for national governments will be to concentrate resources to research alternative energy source to deal with the energy crisis, budget for high energy physics research will be greatly reduced, not increased.

Let's see how much electricity the LHC consumes. From CERN provided information. We know it consumes 200 mega watts of electricity, equivalent to half of the consumption rate of the whole Geneva City. Running the machine for one year would consume 1.75 billion kilowatt*hour of electricity. The electricity now in USA costs almost 12 cents per kwh, almost double the figure less than 2 years ago. By the time LHC is really to do some real physics experiments, I expect electricity could cost as much as half a dollar per kwh. That would put the electricity cost at 0.88 billion dollars per year. That alone is already more than CERN's annual budget.

And it consumes a huge amount of fossil fuel to generate that electricity. At half kilogram per kwh, it burns 0.88 billion kilogram of coal to generate 1.75 billion kwh. That's 8.8 million tons of coal. Takes one million trips of huge trucks just to transport that amount of coal. I am not sure where the morality is to burn all the fossil fuels for some vague physics result that no one even knows for sure will come out, while citizens are having a hard time keep themselves warm in the winter.