Submission + - It took 100 years, but maths conundrum is solved
w1z4rd writes: "A mathematical problem that remained unsolved for more than a century has finally been cracked by an international team of 18 scientists.
The puzzle, which is so complex that its handwritten proof would cover an area the size of Manhattan, took researchers four years to unravel and takes up as much computer space as 45 days of continuous music in MP3 format. The human genome hold 1 GB of data, this puzzle is 60 GB."
The puzzle, which is so complex that its handwritten proof would cover an area the size of Manhattan, took researchers four years to unravel and takes up as much computer space as 45 days of continuous music in MP3 format. The human genome hold 1 GB of data, this puzzle is 60 GB."
Submission + - Reactionless Space Drive
Jeffrey Beer writes: "REACTIONLESS SPACE DRIVE
by Jeffrey Beer
The device described below, as invented by the author, is intended as a propulsion system for spacecraft. It is able to generate a forward motion without ejecting mass rearward.
Name of device: Relativistic Variable Mass Synchrotron
What it does: Asymmetrical Momentum Force Generator
The "reactionless drive" consists of a circular particle accelerator, a
synchrotron. The elecrons would travel around the synchrotron at a constant
speed. But, on half of the circuit, the electrons would be made to vibrate in a
direction perpendicular to the path being travelled (probably with electrostatic
plates), moving as close to the walls as possible with each oscillation. So, there would be a vertical, up-down oscillating movement of the electrons during one-half of their journey around the track.
If they were oscillated at near light-speed, their mass would increase over this portion of their journey around the track. Therefore, the momentum
generated would be greater on that side of the track and the entire synchrotron
would experience a net force in that direction. Of course, with the current technology available, the force would be very small, probably too small to be practical. But, it would still be interesting in that it would demonstrate that a reactionless drive is theoretically possible altogether.
The Relativistic Variable Mass Synchrotron is able to generate a net force using the principles of Einstein's relativity theory. It is important to note that the speed of the electrons around the track is not changed. Only their vertical motion is changed over part of the track. This way, their variable mass can be used to generate a unidirectional force.
An alternative method would be to have the electrons travel up and down a cylinder with negatively charged electrode plates at each end. After the electrons (or other charged particles) bounced off the bottom electrode, the group of electrons could be made to spin rapidly in a cyclonic fashion just above the inside wall of the cylinder, in a motion perpendicular (horizontal) to the direction of their journey up the cylinder. By being made to spin at near-light speed, their mass would increase. Then, as the electrons bounced off the negatively charged top electrode plate and were sent down the cylinder, the momentum of the impact would be transferred to the cylinder. During their downward journey, the rotating motion of the electrons would be slowed or stopped, thus reducing their mass. They would then be deflected off the bottom electrode, imparting less momentum to the cylinder than they did at the top. Then, after the deflection, the electrons would be accelerated again before bouncing off the top cylinder. Note that mass is not increased or decreased during the acceleration phase, but only during the time when the electrons are coasting. As a result, there would be a net upward force generated on the cylinder, prompting the cylinder to move upward, provided it is not restrained by a gravitational field or other impediment. The principle is the same as with the circular particle accelerator described above.
These devices, if perfected, would function as a method of propelling spacecraft without ejecting mass. The End."
Submission + - Windows Defender misses 47% of malware
Mytob writes: "Windows Vista antispyware software, Windows Defender, has been slammed after it failed to detect almost 50 percent of malware threats thrown at it during the past year.
http://www.pcadvisor.co.uk/news/index.cfm?newsid=8 474"
Submission + - IBM to help game devs grok Cell
Piri W. writes: IBM is hooking up with Vivendi Universal to offer a 'developer jam session' aimed at teaching game developers how to take better advantage of the Cell CPU found in the PlayStation 3. During the jam sessions, IBM will try to answer two questions likely to be asked by developers:
'IBM can help a lot more with the second question than it can with the first, although the first one is by far the hardest. It's also the case that the Xbox 360 won't support the same degree of task-level parallelism that Cell will, so developers who design their games from the ground up for the PS3 will have their work cut out for them when porting to the more popular Xbox 360. It remains to be seen if the amount of work that it will take to really get the extra mileage out of Cell will pay off with such a relatively small installed base of PS3s.'
- How much task-level parallelism can we wring out of this game?
- Once we've made the game as parallel as possible, how can we get the best per-task performance out of the SPEs?
'IBM can help a lot more with the second question than it can with the first, although the first one is by far the hardest. It's also the case that the Xbox 360 won't support the same degree of task-level parallelism that Cell will, so developers who design their games from the ground up for the PS3 will have their work cut out for them when porting to the more popular Xbox 360. It remains to be seen if the amount of work that it will take to really get the extra mileage out of Cell will pay off with such a relatively small installed base of PS3s.'
Submission + - notMac Challenge to Create Open Source .Mac
An anonymous reader writes: Yesterday in his blog for the New York Times, David Pogue wrote up the notMac Challenge. The site's raising contributions from the public to encourage the development of an open-source alternative to Apple's .Mac service. The post mentions that "the value of the prize pool has grown to over $6,000", but when I checked out the site this morning the total had grown to over $7,100.
