Wednesday, September 10, 2008

To err is human...

Some excerpts & understanding from:
EINSTEIN'S MISTAKES: THE HUMAN FAILING OF GENIUS by Hans Ohanian.

The book does not try to diminish the man's extraordinary achievements. Physicist Ohanian shows that Einstein was human like the rest of us. Like a real scientist trying different approaches, Einstein made many errors. Part of his greatness was the willingness to make mistakes

The first derivation of m=E/c^2 is in a 2-page addendum to "The Electrodynamics of Moving Bodies." There is an error in this hastily written proof, and more mistakes in the second, third and fourth proofs of 1906-07. Only in 1911 did Max Laue produce a full proof. Einstein's fifth proof in 1914, his sixth proof in 1934 and his seventh proof in 1946 also contained errors. By this time nuclear reactions and the atomic bomb had proved to the world that E=mc^2.

EINSTEIN'S MISTAKES finds errors in 4 of the 5 seminal papers, including the photoelectric effect and the size of molecules from Brownian motion. Einstein's PhD thesis was full of mistakes. The road to General Relativity contained many errors and dead ends. In 1916 Einstein made a mistake interpreting Mach's Principle. The last decades of Einstein's life were spent in a fruitless search for Unified Field Theory.

Attempting to unite electromagnetism with gravity, he tried many approaches which all failed. The book lists dozens of mistakes stretching across an entire career.Einstein's greatest blunder was the cosmological constant. In a 1917 paper Einstein dared to imagine the entire Universe.

According to General Relativity, mass causes Space/Time to be curved. Einstein realised that enough mass would cause the Universe to be curved into a sphere of 4 dimensions. Travel in any spatial direction would be confined to the sphere. Such a sphere would collapse under its own gravity, unless it were already expanding. To support the sphere Einstein invoked the fudge factor of a cosmological constant. If Einstein had proposed an expanding Universe it would have been one of history's great predictions. No doubt he would have been ridiculed for having no supporting evidence. That's why it is called a prediction, boys!

If Einstein had waited long enough, Edwin Hubble would eventually have proven his amazing prediction. When faced with Hubble's evidence Einstein had to admit that the cosmological constant was a blunder.

Fortunately Einstein had a great patron in Max Planck. Planck was an editor of Annalen Der Physik, otherwise Einstein's great papers may not have been published in 1905. In later years Planck was first to hail Einstein as a new Copernicus. Planck's blackbody formula was an experimental result; many years passed before someone found a mathematical derivation.

Einstein had another regret: Submitting to refereed journals. Around 1936 he submitted a paper to Physical Review, the leading American journal. Despite Einstein being by then the world's most renowned scientist, his paper was returned with anonymous comments from a referee. Einstein withdrew the paper and henceforth avoided PRL and any journal with anonymous referees. This was a blessing in disguise, for the paper contained an error.

A child could figure out that R=ct and GM=tc^3. Proposing this gets the most tangled mathematical objections: the units don't add up (they do), the metric is (1, 1, 1, 1) rather than (1, -1, -1, -1),...and so on. We can see why these people, despite their expensive education, have never come up with anything original. By their own admission, such people referee papers. If they were reviewing Copernicus, they would insist that everything be expressed in terms of a fixed Earth.

History gives us many lessons for today. Even an Einstein can make mistakes. The cosmological constant was a blunder and still is. Predicting an expanding Universe or a shrinking speed of light is worth the wait for confirmation. Don't feel bad if refereed journals reject your stuff. A great physicist is prepared to make mistakes, lots of them.

The book admires Einstein's "mystical, intuitive" approach. He used mistakes as "stepping stones and shortcuts" to success. We can still learn a lot from Einstein.

Tuesday, September 2, 2008

Indo-US Nuke Deal: Some more facts

Prove me wrong (ofcourse with facts and figures), I'd feel extremely happy to change my opinion. I just want to keep the facts infront of people.

Nuclear power will be critical for the country’s long-term energy security, no doubt on that. It is important to understand that the n-deal cannot be central to achieving our 3-stage nuclear power programme. Even Dr Anil Kakodkar calls import n-power to be an “additionality” to the long-term projections for our indigenous nuclear capacity.

We want Plutonium out of our first stage, PHWRs contribute that for our 2nd stage. Even LWRs are expected to do so. But do you know that LWRs will not give as much plutonium as PHWRs give..?? (I dont have much data on these proportions, if some body can subsantiate, I'd be thankful. Even I'd feel happy to be "proved" wrong..!!). So if we are very much dependant on importing LWRs, it may ultimately reduce attention towards PHWRs, hence plutonium; which will ultimately affect the 2nd stage of our 3 stage programme. So the affects will be seen in long term.

Now comes energy security. All will agree that less than 10% nuclear contribution cannot be termed "critical". It stands to reason, therefore, that n-agreement cannot meet the energy needs. If there is no import contribution, it is certainly possible to live with a 5% n-component. May be, it will be prudent to import coal and natural gas and implement new thermal and gas-based projects to meet energy needs.

I certainly dont support coal for long term needs, but instead of giving a nod to the Nuclear imports, I'd certainly like to invest all that money which is planned for nuclear imports to be invested in Solar Power R&D/installations, which has all the abilities to cater long term needs. Indeed for our short/medium term needs, coal/gas is a must.

Imports would become necessary only if 2nd stage does not succeed as envisaged and consequently the 3rd stage fails to take off. The only option then would be to expand the PHWRs and LWRs base, may be using imported uranium and LWRs. But then long term reliance on n-power would not be a correct option to think for. So from this perspective, imported nuclear power is not essential at this point of time. If some additional power can come in without any attendant constraints (policy-related compromises), it is acceptable.

The current requirement of natural uranium is about 600 tonnes a year and the current production is less than half that. However, the augmentation made will ease the crunch significantly in about 6 months, if DAE officials are to believed. UCIL is investing Rs.3,100 crore to open new mines and set up processing plants in Jharkhand, AP and Meghalaya. In Jharkhand alone, Rs.650 crore is being invested. Investment of Rs.1,800 crore is proposed for setting up two uranium mining plants in AP.

The CAG of India observed in 1999 that one of the main reasons for the DAE falling short of the original target of 10,000 MWe by 2000 was the large shortfall in government funding in 1980s & 1990s. Surprisingly Manmohan Singh was the Finance Minister and Montek Singh Ahluwalia was the Secretary for Economic Affairs and Finance Secretary during 1990s. Strangely now, in their new-found faith in nuclear power, they are championing the cause, but through imports!
Coming to the cost components. Importing would be much costlier (about 9 crore/MWe "without the interest" during construction on the borrowed amount) than the capital cost of indigenous PHWRs at about Rs.7 crore/MWe. The price of processed and fabricated uranium fuel is $1,625/kg. A 1000 MWe LWR requires nearly 1000 tonnes of uranium fuel over its lifetime, which means an additional $1,625 million over the $2,000 million capital cost, if fuel is to be stocked for a lifetime. This in the current exchange rates amounts to Rs 9310 crores for building & running 1 LWR...!!!

Let's assume that such large resources can be raised through the market; dont you think the money would be better spent in implementing a wider base of the PHWRs, in increasing production of domestic uranium resources, and in spending some part of it towards the Solar Power, which is mis-interpreted to be costly, in the scenario when we are ready to push thousands of crores of rupees importing nuclear power...????????