Tuesday, December 21, 2010

How much snow

In the last three weeks there was about 2 meters of snow falling over London Ontario that caused the University to be closed for 4 days and the city buses not to operate for almost two days, due to the heavy load of snow on roads.


How much this city became heavier then? 


With the area of almost 400 (km^2), so the volume of snow is 0.8 billion (m^3). The mass density of freshly fallen snow is around 10% of that of water, let let be it 100 (kg/m^3).


So the total mass of the snow is huge: 80 billions (kg). 


This is equal to the mass of a near-Earth asteroid that caused a brief period of concern in December 2004 because initial observations indicated a small probability that it would strike the Earth in the year 2029!


How much power does this mass create?


If we consider the speed of rain droplets is a few meters per second, let us consider the speed of snow is at least 0.1(m/s), which produces the kinetic energy 1/200 (J/kg).  This much snow fell on the city in 4 days therefore the rate of falling was 80 billions kilograms per four days, or 200,000 kg/s. The total power is 1000 Watts.


This snow generated 5% of the solar power radiated by sun over this city.
    

Friday, May 21, 2010

QISS 2010

The wonderful QISS 2010 workshop was definitely a success for the organizer Institute. We saw the most modern form of qubits in semiconductors, superconductors, and the buckyball fullerenes. More information can be found in here, where the talks are supposed to become available online soon.

Quantum Amplification Effect on black holes

Black holes radiate.

But recently it is shown they even more radiate!

In fact when their horizon fluctuates, they radiate on two or three frequencies that are heavily resonated, like a quantum amplifier.

These lines are at the range of frequency sensitivity that INTEGRAL may become able to find them. Perhaps we have observed them and do not recognize them as black hole QAE lines.

These lines could be foud in evenly or unevenly spaced fashion. in fact, Yakov Bekenstein and Viatcheslav Mukhanov predicted these lines (if are more than two) are exactly evenly spaced. With the support of theories that predict the spectrum of area scaling with the square-root of integers, we predicted they must be found in an unevenly-spaced fashion.

Details can be found in my recent Physical Reviews D paper...



This figure illustrates a quantum black hole horizon in the vicinity of a null boundary (the black sphere). In other words, you see a black hole as the interior black sphere underneath a discrete shell (the outer shell) that represents the hole's horizon area fluctuations.

The spectrum of a black hole radiation should be discrete, intense, and narrow line on top of weak the Hawking radiation.

The search for these lines in observational data is continued...

Thursday, April 08, 2010

How to work with jpeg2ps software in Windows



How to work with jpeg2ps software in Windows:

1- After installing GSView (read here for instruction), download jpeg2ps from here, (thanks to sourceforge.com!)

2- After downloading is finished, click on the file and install the software. Note at what folder it's going to be installed. Its default location is usually at "C:\Program Files\GnuWin32\"

3- (Copy and) paste a JPEG, which you want to convert it into eps, into "C:\Program Files\GnuWin32\bin".

4- On Windows "Start" click on "Run" and write in its empty box "cmd". A black DOS window will appear inside which a default directory is written, usually it is "C:/Program Files/Username>". Each time you write "cd.." in front of the ">" and enter this folder goes one root backwards, so by repeating this you can go back to "C:>". Write "cd Program Files\GnuWin32\bin" or "cd [The "bin" folder address where you installed jpeg2ps at]. Now you are where the software jpeg2ps is! (If you are DOS expert you know how to write shortcut.)

5- Write "jpeg2ps" and you'll see the option menu. It is time now to actually convert a sample picture. Assume the file "sample.jpeg" (which is located at C:\Program Files\GnuWin32\bin) should be converted to EPS.

6- Write "jpeg2ps sample.jpeg > filename.eps". Doing this will create the file "filename.eps" in the folder C:\Program Files\GnuWin32\bin. This will be your desired eps file. You can change the resolution as well as other options.

Enjoy!


More information:
How to convert quality jpeg images into eps. (Guage Invariance)

Tuesday, March 02, 2010

Timing backwards

... Let's assume we are watching 10 seconds of a basketball game. It is right at the moment when two players are standing near the basket and the ball is passed from one player to the other who reside under the basket. This player after, grabbing the ball, turns about his waist and shoots the ball into the basket such that the ball enters into the net from its below. We no longer see the game.

Now consider time goes backwards. The ball enters the basket from above, one player grabs it and passes it to the farther player. Consider the way how the players act is such that we cannot distinguish the difference between the first scenario and the second one only by watching their action.

It seems in the lack of the rest of the play, we cannot distinguish between these two degenerate scenarios. However, there is a tiny difference between the two that breaks the degeneracy. In fact, by noticing that we can distinguish between the correct and the backward time directions. Guess what is the point?

Mohammad H. Ansari