Posted by bert hubert Sat, 24 May 2008 08:37:00 GMT
Mirjam & Bert are proud to announce the birth of their son Maurits Hubert! Mother, son & father are doing very well.
Feel free to email the little guy on maurits@hubertnet.nl!
Picture when Maurits was only an hour old:
And a slightly geeky Droste Effect photo:
Posted by bert hubert Tue, 13 Nov 2007 12:42:00 GMT
Exactly one year ago today, my father passed away, less than a year after my mother did.
Here you can see them in happier times, together with the other subject of this post:
While we mourn their passing today, not all news is bad. I’m happy to announce Mirjam and I are expecting a baby!
We’re very happy, but sad we won’t be able to share the good news with my parents. But: life goes on - which is literally true in this case.
Bert & Mirjam
Posted by bert hubert Sun, 11 Nov 2007 10:36:00 GMT
While running the risk of turning this blog into a lecture series, I can’t resist. This post will dive into cryptography, and I hope to be able to transfer the sense of wonder that caught me when I first read about Diffie-Hellman key exchange many years ago.
Let’s assume you are in a room with two other people, and that you want to share a secret with one of them, but not with the other. In the tradition of cryptography, we’ll call these three people Alice (you), Bob (your friend) and Eve (who wants to ‘Eavesdrop’ on your secrets).
Let’s also assume that the room is very quiet, so you can’t whisper, and everybody can hear what everybody else is saying. Furthermore, you are far enough away that you can’t pass paper messages.
So how could you (Alice) share a secret with Bob? Anything you want to tell Bob, will be overheard by Eve. You might try to think up a code, but you’ll still have to explain the code, and both Bob and Eve will hear it.
It turns out that using the magic of public key cryptography, this is possible - sharing a secret while people are listening in.
The room with Alice, Bob and Eve is not a very relevant example, but replace Alice by ‘The allied forces’, ‘Bob’ by a resistance fighter equipped with a radio, and ‘Eve’ by the occupying enemy, and things start to make sense.
Or, in today’s terms, replace Bob by Amazon.com, and Eve by a hacker interested in getting your credit card number.
To send a secret, two things are needed: an ‘algorithm’ and a ‘key’. A famous algorithm is the ‘Caesar cypher’, which consists of shifting all letters by a fixed amount. So an A might become a B, a B would become a C etc etc.
The key in this case is how much you want to shift the letters, in the sample above the key is ‘1’. If the key had been ‘2’, an A would’ve become a C, a B would’ve become a D etc.
Typically, you can discuss the algorithm in public, but you need to keep the key secret. In terms of Alice and Bob, they will be able to communicate in secret once they’ve been able to establish a key that Eve does not know about.
Once everybody has agreed to use the Caesar cypher, the problem shifts to exchanging how many letters we will shift. We can’t just say this out loud, since both Bob and Eve will hear it.
Way back in 1976, Whitfield Diffie and Martin Hellman published the details of what has become known as the Diffie-Hellman key exchange algorithm, although they both credit Ralph Merkle with some of the key ideas.
The process basically works as follows. Alice and Bob each think of a random number, that they keep a secret. Then they both do some calculations based on this number, and say the result of those calculations out loud.
Then both Alice and Bob combine the results of the calculations with their own secret random number, and out pops a shared random secret number. This shared random secret number is now known by Alice and Bob, but not by Eve. And it is this secret that now becomes the key.
Eve heard both Alice and Bob say a random number, exactly the same numbers that Alice and Bob heard. Yet only Alice and Bob now know the shared secret. How is this possible?
The trick lies in the calculation, by which means Alice and Bob only shared parts of the numbers they chose initially. Then both Alice and Bob combined those parts with their full random numbers.
It is this trick of revealing only parts of random numbers, and then combining the part of the other party with your full number, that leads to a shared secret.
On this page I wrote a very simple Diffie-Hellman example program that runs entirely within your web browser. You can either use it alone, or with a friend - which is the most fun. It works over the phone, or over an instant messenger (IRC, MSN etc). Follow the instructions, encode a message, paste it to your friend, and if your friend followed the instructions, and he pastes the encoded message into the decoder, he should see your secret message!
This is even more fun in a chat room with actual Eve’s present.
Please be aware that the sample is a joke - don’t use it to share real secrets! However, the technology it employs is real, and this truly is how people exchange keys - only the numbers are far larger (300 digits), and the actual encryption is not a Caesar cypher.
More information can be found on the wikipedia page about Diffie-Hellman, especially in the ‘external links’ section.
Posted by bert hubert Thu, 20 Sep 2007 19:57:00 GMT
I’ve long been a fan of some of the techniques Dan Bernstein uses to leverage the power of UNIX to achieve complicated goals with little effort. For example, he uses a technique called Chain Loading to clearly separate and insulate several programs from each other by loading a new program *in place* of the current one, once a critical task has been performed, like checking a user’s credentials.
This guarantees that the outer program, that might actually be exposed to the internet, can restrict itself to very basic functionality, and only launch an inner, more useful program once authentication has completed.
Other tricks are to leverage UNIX user names to insulate various programs from each other, leaving the task of getting the access control details right to the very well tested operating system (which we need to rely on anyhow).
While sometimes unconventional, techniques such as those described above can simultaneously reduce code complexity AND increase security, by more or less hitching a ride on top of existing functionality.
Some time ago, I was involved in the development of a computer program with a classic ‘producer/consumer’ problem. We were inserting events in the database, and wanted to scale by getting a dedicated and very fast database server. To our surprise, getting an additional, and far more powerful system did not improve our performance, and in fact made things far worse.
What happened? It turns out we were doing a lot of small inserts into the database, and even while we were using a transaction, each of these inserts incurred a slight latency penalty, caused by the query & answer packets having to travel over the network. And when doing hundreds of thousands of queries, even half a millisecond is a lot of time. Add in operating system and TCP overhead, and the end to end latency is probably even higher. The obvious solution is to no longer actually wait for the inserts to complete, but to transmit them to the database asynchronously, and continue to do useful work while the packets are in flight and being processed. This way, no time is wasted waiting.
Since most database APIs are synchronous, a separate helper thread of execution needs to be spawned to create the fiction of asynchrony, and this is where things get interesting.
In the PowerDNS nameserver, a complicated ‘Distributor’ abstraction is used to send queries to database threads, and this Distributor contains locks, semaphores and a zoo of other concurrent programming techniques to make things work well. For example, we need to perform checks to see if we aren’t building up an unacceptable backlog of queries, and block if we find we are. This comes with additional choices as to when to unblock etc. I was not looking forward to reimplementing such a thing.
Additionally, our database interface needed to offer an extra feature: every once in a while a query comes along that we DO need to wait for, and because of coherency issues, such a query can only be executed once all queries ‘in flight’ have finished.
So we spent some time pondering this, and suddenly it dawned on me that many of the features we needed exactly match the semantics of the venerable UNIX ‘pipe’.
A pipe is normally used to communicate between two processes, as exemplified by this sample shell script command, which shows us the largest directories on a disk:
$ du | sort -n
The program ‘du’ generates a list of directories and their sizes, which is then fed to sort which outputs this in ascending order. However, nothing prohibits us from using a pipe to communicate with ourselves - and as such it might be a might fine conduit to pass database queries through to our database worker thread.
This has some very nice benefits. Pipes are incredibly efficient, since a lot of UNIX performance depends on them. Additionally, they implement sane blocking behaviour: if too much data is stuck in the pipe, because the other process does not take it out again quickly enough, the sending process automatically blocks. The operating system implements high and low water marks to make this (un)blocking happen efficiently.
Furthermore, pipes guarantee that data up to a certain size can either be written as a whole, or not written at all - making sure we don’t have to deal with partial messages.
Finally, pipes automatically detect when the process on the other end of them has gone away, or has closed its end of the pipe.
However, not all is good. In order to transmit something over a pipe, it must be serialised into bytes - we can’t transmit ready to use objects over them. Additionally, because pipes implement ‘stream’ behaviour, we need to delineate one message from the other, because the pipe itself does not say where a message begins and ends - unlike datagram sockets for example.
And this is the clever bit of our idea. As stated above, pipes are usually employed to transmit data from one process to the other. In our case, the pipe goes from one thread of execution to the other - within the same process, and thus within the same memory space. So we don’t need to send serialized objects at all, and can get away with transmitting pointers to objects. And the nice thing is, pointers all have the same (known) length - so we can do away with both delineation and serialisation.
Additionally, pointers are a lot smaller than most messages, which means we can stuff more messages in the same (fixed) size of the pipe buffer.
So, are we done now? Sadly no - we have the additional need to be able to ‘flush the pipe’ in order to perform synchronous queries that we do need to wait for.
This is where things get complicated, but for those who really want to know, I’ll explain it here. It took almost a day of hacking to get it right however, and I’m explaining it for my own benefit as much as for that of the reader, since I’m bound to forget the details otherwise.
If a synchronous query comes along, we need to flush the pipe, but UNIX offers no such ability. Once we’ve written something to a pipe, all the kernel guarantees us is that it will endeavour to deliver it, but there is no system call that allows us to wait for all data to actually be delivered.
So we need to find a way to signal a ‘write barrier’, and the obvious way to do so is to send a NULL pointer over the pipe, which tells the other end we want to perform a synchronous query. Once the worker thread has seen the NULL pointer, it unlocks the single controlling mutex (which is the return signal that says “got you -the pipe is empty”), and then waits for further pointers to arrive.
Meanwhile, the sending thread tries to lock that same mutex immediately after sending the NULL pointer, which blocks since the receiving thread normally holds the lock. Once the lock succeeds, this tells us the worker thread has indeed exhausted all queries that were in flight.
The sending thread now performs its synchronous database work, knowing the database is fully coherent with all queries it sent out previously, and also knowing the worker thread is not simultaneously accessing the connection - since it is instead waiting for a new pointer to arrive.
If our program now wants to perform further asynchronous queries it can simply transmit further pointers to the worker thread - which oddly enough does not need to retake the mutex. This is what caused us many hours of delay, because intuitively it seems obvious that once the sending thread is done, it must release the mutex so the worker thread can retake it.
As it turns out, doing so opens a whole world of nasty race conditions which allow synchronous queries to ‘jump the queue’ of asynchronous queries that are in flight and have not yet arrived.
So, the sequence is that the worker thread only unlocks the mutex, while the sending thread only locks it.
And this basically is it! So how much lines of code did we save by using the magic of UNIX pipes? The pipe handling code takes all of 90 lines, whereas the Distributor code of PowerDNS takes a round 300, even though it does not offer synchronous queries, does not automatically block if too many queries are outstanding, and most certainly couldn’t implement the sensible wakeup ability that UNIX pipes do offer.
Oh, and you might be wondering by now, did it help? Indeed it did - our program is now at least 20 times faster than it used to be, and there was much rejoicing.
Posted by bert hubert Sun, 26 Aug 2007 16:18:00 GMT
Ok - Steorn is quieting down for now, and it got enough attention anyhow, so it is time to look a bit into the things behind the appeal of alternative energy sources.
Many readers will recall that in the past, there was debate as to when the ‘oil would run out’, and that this date was supposed to be somewhere in 2045 or so, which was more or less far enough away not to worry about it.
At least I remember thinking about it like that back in school. It is amazing how this sentiment fooled us for so long. Modern tubes of toothpaste are easy to empty down to the last bit, but in the past this wasn’t so. This should’ve told us something.
Oil is not like modern toothpaste, it is like ketchup. Far before it has run out, it becomes hard to extract. And oil is remarkably worse than ketchup.
Back in 1956, one of Shell Oil’s scientists noticed that wells started to become less productive once 50% of their contents had been extracted. He then proceeded to predict US oil production based on this assumption, and correctly calculated it would peak somewhere in the late 1960s, and decline from that point onwards. And so it did.
Additionally, he extrapolated this result to the whole world, and determined global oil production would go into decline somewhere after the year 2000.
Nobody much liked this prediction, and it was widely ridiculed. New wells would continue to be found, and importantly, new techniques would enable us to extract more and more oil from existing wells.
As it turned out, especially this last prediction was correct, which is why the world production of oil hasn’t declined already.
However, no major new fields have been found over the past decade.
Many players in the oil industry now believe the predictions, and agree that oil production might decline from 2010 onwards, or perhaps a bit later.
Controversy aside, the International Energy Agency has produced graphs of oil production and demand since 1974, and it is clear that production will one day be overtaken by demand.
It is easy to see why - as it comes out of the ground, oil is not immediately suitable for all kinds of use. For many purposes, it first needs to be ‘refined’. Building a refinery is hard work, and typically takes up to a decade. Additionally, environmental rules mean that it is easily possible to spend a similar amount of time just getting permission to build.
No major refineries have been built over the past years, and no major refineries are nearing completion. The existing refineries are running at or near peak production.
On the demand side, the world economy is growing at an unprecedented clip.
The few graphs that plot oil production and demand in one plot (readers, if you know of any, please comment!) typically show a ‘and then a miracle occurs’ event when demand is about to overtake supply.
This reflects the usual market behaviour that once oil becomes scarce enough, prices will rise, and oil that was hitherto uneconomical to produce becomes economically viable. In other words, exploding prices make more oil available.
But as remarked previously, refineries are already running flat out. This means that no miracle will occur in the immediate future, and oil might very well run out temporarily.
To reiterate, this does not mean the oil is gone, just that it isn’t available at the rate we need it.
This is the scary bit, and the main reason I worry. Already we see posturing by the big oil suppliers and consumers. China is pouring money into Africa, and has even deployed part of its army in certain countries to make oil production possible.
Russia is throwing its weight around in a frightening way as well, and making it clear not all of its customers are equal. It plays geopolitics both with hydrocarbon availability and pricing.
The various armies in the Middle East speak for themselves. A peaceful Middle East produces more oil, and it might very well sell it preferably to its occupiers or sponsors.
Here in Europe, we appear to believe oil might become mighty expensive, but that we’ll weather it.
But if oil becomes truly scarce, will market prices influence who will get access to it? Or will it be supplied to those countries with the ability to project power, and back up their monetary offers with military encouragement?
Or might suppliers become king-makers, with the power to determine which economy lives or dies?
Our European belief that our ability to pay steep prices will allow us to continue as normal might be seen as exceedingly silly by then, possibly comparable to Neville Chamberlain’s appeasement policy in the 1930s.
It is happening already, but crunch time is not yet upon us. Some countries have already had problem getting access to enough energy, mostly those who (like Europe) depend on Russian oil and gas.
The crunch might be postponed if the economy stops growing at this rate, it might be advanced if any of the major refineries is damaged by terrorism, weather or bad luck.
At any rate, the issue should start making more headlines in the near future.
Some countries have already accepted that we should start building more nuclear power plants because the energy is running out. However, building such installations also takes decades, and it has been argued we’d need to open a new power plant each month or so to make up lost ground.
Coal is currently environmentally harmful or expensive, but might save part of the industry for some time.
Wind and solar, although interesting, struggle to generate an appreciable fraction of our world energy need.
Tar sands, sand that contains oil, are interesting but not for the near future. They might make Canada extremely rich though.
Google on ‘Hubbert Peak’, and head on from there. ‘Peak oil’ is also a nice phrase to search on. The International Energy Agency has long published honest and truthful graphs that presaged the issue, but up till recently the IEA did not put this into words. Recently they’ve begone to describe the near future oil situation as ‘extremely tight’.
Posted by bert hubert Wed, 04 Jul 2007 22:29:00 GMT
Well, it might’ve been too good to be true.
First the announcement that internet streaming of the ‘Steorn’ device over at Kinetica Museum would start at 6PM, which was later “clarified” to mean 6PM US eastern time.
And when that time passed, nothing happened. After a while, a notice appeared that due to technical difficulties, streaming would start on July 5th.
Perhaps this is the beginning of the end for Steorn.
Update: Steorn has confirmed the device is not operating as it should, but they say they are working on it, and intend to turn on the streams tomorrow, even if the device is still not working, so we can see “stressed engineers” trying to fix it.
In one of my first posts on this enigmatic company, I mentioned the possibility of them deluding themselves, and I’m afraid the things that have happened over the past few days point in that direction.
I’d still be very happy if Steorn turned out the be on to something, but the signs are not good..
The websites of Steorn and Kinetica still promise a demo, so perhaps they simply are having problems streaming. Will keep you posted.
Posted by bert hubert Tue, 03 Jul 2007 06:33:00 GMT
Life is quickly getting silly on the Steorn front (for more details, see my previous post).
Reliable sources have now confirmed a demo *IS* being setup, and although most sources are bound by NDA, it has become clear the demo is this week, and most likely at the Kinetica Museum.
Update: update, webcam images are appearing here!
Update: the Kinetica website now contains an announcement that it is hosting a new exhibition starting Thursday, and that details will be announced on Wednesday.
Update 2: An article on RTÉ news reports that Sean McCarthy says the device will be demonstrated tonight from 6PM London time, and that it will be lifting a weight to prove it is generating energy.
Additionally, a short movie has surfaced last night showing someone who looks like Sean McCarthy (the Steorn chief executive) smoking a cigarette across the Kinetica museum. Sean is wearing a t-shirt that says ‘CEO versus CoE’, where CoE stands for Conservation of Energy - the basic law of physics their device is claimed to break.
This movie is classic viral marketing material, which in itself tells us something: Steorn is being REAL serious about generating a hype. They’ve previously availed themselves of the services of Citigate Dewe Rogerson, a high-end public relations firm. This viral is a strong indication they are again taking PR seriously.
If they are as serious as this about getting massive media attention, this will only be the beginning of the onslaught. By itself this movie will not turn heads, but it might be a good start.
We’ll only know more if and when the demo arrives, and many are sceptical about the chances of being convinced by a demo, but for now, expect the hype to increase, with an expected peak on Saturday the 7th coinciding with the Live Earth concert.
For more information, see the Steorn homepage, the Free Energy Tracker Blog, the Dispatches from the Future blog, the Fizzx forum and the relevant Wikipedia page. Another interesting place to look is the Steorn Forum, but be aware this place is populated by all and sundry, and heavily edited by moderators.
Posted by bert hubert Sun, 01 Jul 2007 18:28:00 GMT
Quick plug of my new laptop, a spiffy Dell XPS M1210. Kudos to both Dell and Ubuntu, everything just works, and it just works very well. If you need a small but powerful laptop, and want to run Linux, you should consider this one!
Ok, on to the hype.
Update: earlier entries on Steorn are here, here, and here.
This week saw the launch of the iPhone, perhaps one of the most anticipated technology events in living memory.
On the physics side of things, we are sort of going through the same thing, except a thousand times smaller. Perhaps a million.
To very briefly recap, Steorn hit the scene in August 2006 with an (expensive) advertisement in the Economist newspaper, claiming to have developed technology that generates energy without consuming fuel.
Their story was that nobody believed them, and that they were challenging the scientific community to join a ‘jury’ to prove or disprove their claims.
Since then, they’ve said the jury is now in place, and will report their results when they feel like it. Additionally, in April 2007, it was stated that there would be a publicly accessible demonstration of the technology in London, early July.
And early July is upon us now.
Well, if what they claim is true, Venezuela, Russia, and the Middle-East are seriously out of business. Oil would then remain useful mainly as lubrication, and as an ingredient of many substances.
If their technology works, stock markets will collapse, whole countries will default on their obligations, and the nascent ‘new cold war’ between Russia and NATO will be over.
Since ‘energy out of thin air’ violates most of our understanding of physics, the scientific community is rightfully skeptic. It has been said that extraordinary claims require extraordinary evidence (which I dispute, btw - most new physics started out as small, hard to see effects), so the demo had better be pretty impressive.
There is rampant speculation going on about the nature of the demo, and a few things are known.
The demo will happen ‘early July’, and the public will be able to see the machine, talk to Steorn employees, and view the whole thing over the internet 24/7. Additionally, several people have been invited by Steorn to bring their screwdrivers to open up the device. Lots of people on the various forums have already announced they are bringing heat-sensitive cameras, magnetometers, RF spectrometers and other instruments to verify if any demonstrated device is truly operating without consuming power.
The exact date and location of the demo remain unsure. Steorn has repeatedly stated they are not in it for the maximum amount of money, but that they want their technology to benefit developing countries, as well as being good for the environment.
On Thursday the 7th, London hosts the Live Earth concert, which is all about the environment. This has prompted many to believe the demo will coincide with this concert.
Information about Steorn comes from various sources: their own homepage, the Free Energy Tracker Blog, the Dispatches from the Future blog, the Fizzx forum and the relevant Wikipedia page.
On these various pages, several anonymous or pseudonymous sources have stated contradictory things. It has been reported by a guy called ‘MikeDuke’ that the device will be unveiled to the press on Monday the second of July and Tuesday the third, and might be available for viewing on Wednesday, but surely on Thursday. This is then all supposed to take place at the Kinetica Museum.
Another forum comment reports calling the Kinetica museum and being told they are hosting a private exhibition starting Thursday, about which they can’t say a lot.
Then there is a second poster who says the demo will be held at the Science Museum, starting Friday, and that it will only be announced on Thursday.
Finally, and this one is furthest out, there is an anonymous post stating the demo will be of the ‘rev4.c’ device, and that it will produce 720kW! Not only will it do this, it will emanate a ‘distortion field’!
As said, speculation is rampant. Many are predicting there will be no demo, or that it will be unconvincing. I’m personally on the edge of my seat, having nearly booked a flight to London to see for myself, but at the last minute decided not to go because it is unsure when the demo will be available.
If there is more clarity, I’ll go over and report here.
Posted by bert hubert Sun, 17 Jun 2007 21:07:00 GMT
Ok, people have been harassing me that I should update my blog more often. This strikes me as somewhat odd, blogging is not mandatory - sometimes I feel the need to share some thoughts with my readers (it appears there are 3000 of you!), and sometimes I don’t.
I still don’t have a lot to say, but perhaps this might interest you.
I’ve been following cold fusion, and other ‘alternative’ physics subjects for a long time now, and I keep tabs on quite a number of interesting investigators. Over time it has become clear to me that physics is dangerously locked in to the ‘mainstream’.
Careers are built on getting grants; grants are disbursed by risk-averse boards, journals are very worried about their reputation, and rely on vested scientists to review papers. The upshot of this is that it is very dangerous for a physicist to do ‘interesting’ research.
I felt like this for a long time, but as I’m not part of the physics community, and in fact never got past half of my physics degree, what I feel is not very interesting.
However, when Lee Smolin feels something, it is. He’s written a captivating book called ‘The trouble with physics’. Its main point is that physics has become stuck in a rut called String Theory, which is a complicated set of ideas that has for decades been hailed as the next big thing.
Dr Smolin describes the current state of physics very well, and he appears to confirm the feelings I describe above.
I heartily recommend this book, it is one of the few books that continue where an earlier generation of ‘books for laymen’ stopped.
There are some indications the physics community is more open to ‘interesting’ results again, which should be very good. I’ve made a small list of things I find interesting, and keep track of.
I’ve blogged about this before, but this field appears to be heating up again in a big way. Basically, hot nuclear fusion (which powers the sun, as well as hydrogen bombs), would solve most of our energy problems. However, it turns out to be very hard to make a hot nuclear fusion reactor that survives its own operation AND generates energy.
Cold fusion started out by the claim of Messrs Pons and Fleischman to have found proof of hydrogen fusing under ‘kitchen table’ conditions. It quickly turned out nobody could (reliably) reproduce their results, and controversy ensued. Additionally, our current understanding of physics appears to prohibit ‘cold fusion’.
However, over the following 18 years, it never went away entirely. There is a slow but steady trickle of results that appear to form the smoke to a possible fire. Dr Dieter Britz keeps track of all cold fusion related papers and reports, his database now contains over 1200 items.
Some of the die-hards in researching cold fusion have been a group of employees of a US Naval laboratory, called SPAWAR. Recently, they’ve developed a very simple experiment that reproducibly shows signs of “low energy nuclear reactions”. There has now been at least one replication of their simple experiment, which appears to show the same signs.
The experiment is simple enough that it can be performed at home, and I am sometimes tempted! I’ve since found that quite a number of replications are already going on, so no need to try to build a laboratory at home :-)
More information can be found here
Much of the same goes for experiments with rotating superconductors affecting gravity. It should be realised that gravity is truly unstoppable, as far as we know, there is nothing that could ever ‘shield’ oneself from this universal force.
If one could do that, spaceflight would become a lot easier. It would also put a rather large dent in our understanding of physics - although gravity is poorly understood anyhow.
The Russian metallurgist Evgeney Podkletnov grabbed the attention around 1992 and 1996 with papers describing gravity shielding above a rapidly rotating superconducting disk. The problem was that his disk was very hard to make, so the experiment was not easy to reproduce.
His reports were interesting enough to get NASA to try however, but they never really managed to replicate his conditions. Interestingly, one of the theorists (Ning Li) involved with the experiment appears to have vanished!
This is the stuff of conspiracy theories, but it has been reported that Boeing has at one stage been involved in making devices based on this theory, but this has been widely denied. Meanwhile, Podkletnov has withdrawn some of his papers. All very messy.
However, some time ago, a scientist working for the European Space Agency, made similar claims, which are however very different in detail. Interestingly, Tajmar cs also have theories on why their spinning superconductors produce gravity effects.
It appears their work is being taken seriously. I’ve been in contact with them, and although they didn’t want to reveal a lot, they did say they expected to report new results.
Less controversial, but no less strange, is the current state of our understanding of gravity, which includes such incredible things as invisible objects which do have gravity (dark matter), as well as invisible things that offer ‘negative gravity’ (dark energy). We currently only know that we need these dark things to explain the universe - we just don’t know what lies behind these science fiction-like names!
Unlike other things mentioned in this post, dark energy and dark matter are 100% part of mainstream physics - even though we have only faint ideas on the physical nature of these forms of ‘matter’.
I’ve blogged about this fascinating company before, so I’ll only post an update here.
It is hard to figure out their strategy. They claim to have discovered a device which generates free energy, and that they are trying to make some money from this invention, while also making it generally available. They’ve assembled a jury of 22 scientists which is supposed to validate their technology, but this is expected to take a long time.
In the meantime, their CEO has been posting quite a lot on their forum, dropping hints on how their device works, while otherwise retaining a high level of secrecy.
One of the forum members, Mike Rosing (known as ‘drmike’) heard enough to design an experiment to test at least part of what Steorn intimates lies behind their technology.
This revolves around ‘magnetic viscosity’, which is one of the darker areas of how permanent magnets work. Drmike now has data, but no results yet, as he has to extract these from his heaps of data.
I’ve been in contact with Mike, and we’ve worked out something I might try to program to extract results from his data, but I didn’t yet find time to work on it.
Steorn is said to demonstrate their device in London in July, and Mike and others are going to see this demonstration, and I’m again sorely tempted to join in :-)
More information can be found on the two blogs that follow Steorn, called Free Enery Tracker and Dispatches from the Future.
Posted by bert hubert Wed, 21 Feb 2007 22:13:00 GMT
Enjoyed a fun and stimulating “DNS & Crypto Power Lunch” with Dan Bernstein (left) and Tanja Lange (not in picture). As was to be expected, the intersection of cryptography and (secure) DNS was discussed, and some evil plans might ensue! If implemented in djbdns and PowerDNS, we might actually achieve something..
