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Archive for October, 2005

A Tribute to Einstein

Sunday, October 16th, 2005 -- By ET

I’m always fascinated by Einstein’s life.  I have created a random quote function for this blog on the sidebar with 99.9% of the quotes from Einstein.  Last Tuesday, PBS’ NOVA premiered a program called "Einstein’s Big Idea".  Although having a presentation last Wednesday, I nonetheless sat for two hours to watch that program talking about the elements of Einstein’s famouse quation: E = mc2.  Accompanying that program, PBS has dedicated a site to Einstein

The one quote I like about Einstein is that "I just don’t understant why there is no one understands me, but it seems everyone likes me." 

In 1905, Einstein was a patent officer.  He did not get an academic job because he did not do well in courses other than Math and Physics, and could not get good recommendation letters.  But this is a miracle year:

  • In 1905, Einstein is 26, working on physics on his own. After hours, he creates the special theory of relativity, in which he demonstrates that measurements of time and distance vary systematically as anything moves relative to anything else. Which means that Newton was wrong. Space and time are not absolute, and the relativistic universe we inhabit is not the one Newton "discovered."

That’s pretty good, but one idea, however spectacular, does not make a demigod. But now add the rest of what Einstein did in 1905:

  • In March, Einstein creates the quantum theory of light, the idea that light exists as tiny packets, or particles, that we now call photons. Alongside Max Planck’s work on quanta of heat, and Niels Bohr’s later work on quanta of matter, Einstein’s work anchors the most shocking idea in 20th-century physics: we live in a quantum universe, one built out of tiny, discrete chunks of energy and matter.

  • Next, in April and May, Einstein publishes two papers. In one he invents a new method of counting and determining the size of the atoms or molecules in a given space, and in the other he explains the phenomenon of Brownian motion. The net result is a proof that atoms actually exist—still an issue at that time—and the end to a millennia-old debate on the fundamental nature of the chemical elements.

  • And then, in June, Einstein completes special relativity, which adds a twist to the story: Einstein’s March paper treated light as particles, but special relativity sees light as a continuous field of waves. Alice’s Red Queen can accept many impossible things before breakfast, but it takes a supremely confident mind to do so. Einstein, age 26, sees light as wave and particle, picking the attribute he needs to confront each problem in turn. Now that’s tough.

  • And, of course, Einstein isn’t finished. Later in 1905 comes an extension of special relativity in which Einstein proves that energy and matter are linked in the most famous relationship in physics: E = mc2. (The energy content of a body is equal to the mass of the body times the speed of light squared.) At first, even Einstein does not grasp the full implications of his formula, but even then he suggests that the heat produced by radium could mark the conversion of tiny amounts of the mass of the radium salts into energy.

 I found the following Webring sites quite interesting:

 KryssTal : It’s Relative
A brief introductory account of the Theory of Relativity. This essay uses very little mathematics.

 Muse Astronomy Hobby Page
We have a few Hubble pictures and some astronomy related links you might can use.

 Russell_Einstein Bookstore
Russell/Einstein bookstore, with link to Bertrand Russell listserv at http://groups.yahoo.com/group/BertrandRussell/

 Measuring time and other spatio-temporal quantities
Einstein could not, but with a space-time odometer in addition to a light-clock we can now measure time and spatial distance in the common sense.

 The Dummies’ Guide to Special Relativity
An elementary presentation of Special Relativity for anyone who has successfully completed the 6th grade.

 Albert Einstein Homepage
Do not simply search for Sciences but actually FIND them @ ClickCents FIND Engine

 Your relationships with Albert Einstein
Analyze your relationships with Albert Einstein, in mathematical terms, for presence and strength of the four pillars: commitment, intimacy, passion, and synergy.

 Mike’s Place – Physics & Astronomy Links
Links to Physics and Astronomy Resources.

  Person of the Century
Sensitively sculptured portrait busts, by artist Robert Toth, of Albert Einstein, can be presented as achievement awards or motivational gifts. Owning any of these can be an inspiration to you, your family or your friends.

some new functions in this blog

Sunday, October 16th, 2005 -- By ET

It is extremely easy to add plugins to my blog engine: WordPress.

I feel guilty if don’t do it once in a while.  Recently, I added a few new functions.

1. Subscribe to my blog 

After you sign up, each time I post a new entry in this blog, you will be notified by email. 

2. Subscribe to the comments 

In the comment interface, you can select to subscribe to the comment thread, so each time someone adds a comment to this entry, you will be notified.

3. Weather in Cambridge on the side bar

4. Quote du jour

Each time you reload the blog page, you will get a new random quote on the sidebar.  If you come to my blog frequently, you will find that almost exclusively, the quotes are from Albert Einstein. :-)

 

 

 

 

art work on computer chip

Sunday, October 16th, 2005 -- By ET

From CNET :
More than 10 years ago, Michael Davidson went looking to capture the beauty of microchip circuitry in photographs. In among the transistors and wire traces, he found something unexpected: Waldo.

What he found was that in many chips, you can find cartoon characters or hidden texts with a microscope.

I found it quite interesting to browse through  these pictures.  It’s like the famous painters who leave a cursory signature at some corner of their master pieces, only in this case, they did it with special circuit design.  I’ll hide some text in my next paper then.  Look at the first characters of some paragraph, you might find some interesting. :-)

Next time when I write a paper

CSS color pack

Sunday, October 9th, 2005 -- By ET

 

Found this on J-Blog

 

 

Ning

Thursday, October 6th, 2005 -- By ET

In my research, I study marketing implications of information flows. (read it twice, you will know what I’m talking about). emoticon

So I keep a close eye on the new developments in information technology that may potentially change the way sellers and buyers are connected.  The narrow definition of "seller" and "buyer" involves the two ends of a monetary transaction.  If you have an open mind like I do, you will accept a more general way of defining "seller" and "buyer": they can be the two ends of any exchange or transaction of anything.  Of course, this "anything" can be information.  For example, when I finish writing this article, and you will be stopping by and reading it.  I will be the seller and you will be the buyer.  Although no money is involved, I sell you my "view points", and you pay me your "attention".  You spend some time to read my article instead of using it to do something else, so I have created some value to you (of course, if you find out reading this as a waste of time, the value I create for you is negative).  But we economists can conveniently assume "free disposal", which means if you don’t like this, you can discard it easily and never come back again.  In other words, you can "vote with feet".

Now come back to what I really want to write. :-p

There are many innovative services coming out in the last few years.  If you paid attention to the trends and new services, you can find many exciting websites.  For example, Craigslist, Flikr, Zagat, Del.icio.us, stumbleupon, they do different things with different people as target audience, but they have one thing in common, they facilitate the exchange of information.  It remains unanswered how they substitute or complement traditional marketing channels, and I (with Chris Dellarocas and Neveen Awad) have a paper studying that.  Now there is a website called Ning (www.ning.com) that gives power to ordinary people to establish new websites to offer services to facilitate information exchange.  If all these new services can be compared to Amazon, then Ning is like eBay that empowers small individual sellers.  EBay may not offer as high a quality than Amazon, but the variety offered in eBay can never be dreamed by Amazon.  It is similar for Ning, it establishes the platform for people to play with, and no corporate machine could ever surpass the creativity brought about by the "decentralized" small service providers.

Little By Little

Tuesday, October 4th, 2005 -- By ET

harveydangerHarvey Danger has just released a new album.  Here is a sample song from the album:

[http://blog.mikezhang.com/wp-content/upload/harveydanger_little_round_mirror.mp3]

I learned about this through a friend who saw this got slashdotted.  I seldom listen to rock music, because I need to concentrate on readings most of the time.  In addition, rock music is not the type for my office.  I don’t want Professor Malone to knock on my door to complain.  But this album is very nice, without the free download, I would have never come across this band. 

In his blog, Jeff Lin, wrote:

Record labels will cling to and fight for old models because that’s all they know (and change is always frightening). But there’s no reason why artists should be limited to just that model. Part of this experiment is to see/demonstrate that doing things in this manner can work, that it is a viable option — both artistically and economically.

I hope they can be successful, not just because of the great music, but also because of the big leap in faith.

I have done some research on music distribution in late 2001/2002, I dropped the project because the technology was not ready for big changes.  I even had a proposal of distributing music through P2P framework.  I can see that some music labels are experimenting some similar ideas.  These are all very encouraging, maybe it is time to look again at this issue now…

 
There are quite a few models out there to experiment “selling” “free” content online.  In 2000, Stephen King released a few chapters of his novel and said if he can get enough payment online (on average $1 per download), he will be releasing the rest part.  He did not get enough money in the end.  Recently, there is an online game design website that released a very well designed game system (a 6-page manual about how to play the game).  They did it because they have received enough donation (about $600, as I can remember), they will be exploring that model in the future for their future releases.  (they call it ransom model http://www.danielsolis.com/meatbot/)

To me, these types of pricing model are destined to fail because people like to free ride.  They give no incentive at all for people to pay the money. 

Harvey Danger’s experiment is different, though.  I certainly believe that there will be people donating money (it is much easier to donate small amount of money now than about 5 years ago).  But I doubt the donation would ever cover the cost ($30,000).  The real value should lie in the word-of-mouth associated with the release of the album. 

deleting a list of files

Tuesday, October 4th, 2005 -- By ET

Suppose you have a dirctory of thousands of files, you need to delete some of them.  If the filenames are sufficiently friendly, you can do it easily with a command line.

For example:

rm *.old or rm old*.zip

But, consider this case: files are named with the date they were  generated and there are two types of names

  1. those look like file20051002.zip, and
  2. those look like filemini20051002.zip

Is there a way to only delete the files with "mini" within the filename?

It is not hard to get the list of these files, in linux, it is simply:

ls | grep mini >listfile

Searching in google, I found a linux command called "fastrm" that does delete all files in the list "listflie", but I don’t have it in my Redhat Enterprise Server 3.

So I wrote the following script to do that:

 open (FILE, "< listfile");

while (<FILE>){
        $file=($_);
        chomp($file);
        unlink($file);
}
close FILE;

 Now it is very easy to delete files in the list:

 the command is : ls |grep mini>listfile; perl rmlist.pl;


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