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contact me on unaissait@gmail.com or on facebook clickhere
Tuesday, 23 October 2012
Tuesday, 31 July 2012
Social Networks Get Rewound
TimeHop: Free
If there is anyone out there who journals regularly,you know how enlightening it can be to go back on old entries to see how much you’ve grown. It’s also a good way to remember what you were passionate about or what concerns you had during a different time in your life.
Social networks are the diaries and journals of a more connected generation, but they can still serve the same purpose. Now there's a start up called Timehop that can rewind your Facebook, Twitter, Foursquare and Instagram tweets back a year, and send them to you, answering the questions “What was I doing?” or “How far have I come?”
WIDE ANGLE: Social Networking
All it takes is a quick sign up, which adds the application to your Facebook and allows you to control how much access it has to your information. Daily emails will be sent that detail the history of your page from last year. According to an interview on TechCrunch, co-founder Jonathan Wegener wants to build the site into “the best way of recording, remembering and reconnecting around our digital histories.” The company just earned $1.1 million in funding, which will be used to add more engineers to the project.
Via: TechCrunch
Credit: Timehop
Wednesday, 25 July 2012
Popular Science App Integrates Augmented Reality
Popular Science has released a new app for the iPhone and iPad and also for Android, and this particular app, PopSci Interactive, is designed to help augment, not replace, the hardcopy edition of the magazine. The app is designed to work with the June issue, which is the magazine's annual "Invention Awards" issue (shown to the right). By hovering the iPhone, iPad, or Android smartphone's camera over the text of the magazine interviews, the device should begin streaming video of those interviews.
Note that this requires a camera, so it doesn't work with first generation iPads (like the one I own).
What do people think of this way of integrating technology into the magazine? Has anyone gotten their hands on the June 2012 issue to try it out yet? Is this the wave of the future or just a cool gimmick (or both)?
The Casimir Effect - The Ultimate Free Ride ... into Space?
Science has at times sought to reach further than it can actually deliver, such as in the case of attempts to build a perpetual motion machine.
Some recent reports seem to be dancing dangerously close to this line, as they've reported on the invention of a new propulsion method for spacecraft, based on the work of a teenage Egyptian student named Aisha Mustafa:
The process supposedly uses a method known as the dynamic?Casimir effect, in which?vacuum energy actually results in a force acting on metallic plates. The effect is real, but can it be harnessed to create an effective propulsion system? Mustafa seems to be applying for a patent for her method and is seeking funding to turn it into a viable method of space propulsion.
A patent alone doesn't mean much, of course. After all, there's even a patent on a time machine (as described in Dr. Ronald Mallett's non-fiction book Time Traveler), but time machines (or even time communicators, since that's closer to the actual description of Mallett's device) still haven't been created yet. Just applying for a patent on something doesn't prove that the fundamental scientific concept is actually viable.
Only time will tell whether or not Mustafa's method is more science than fantasy.
Tuesday, 17 July 2012
Popular Science App Integrates Augmented Reality
Popular Science has released a new app for the iPhone and iPad and also for Android, and this particular app, PopSci Interactive, is designed to help augment, not replace, the hardcopy edition of the magazine. The app is designed to work with the June issue, which is the magazine's annual "Invention Awards" issue (shown to the right). By hovering the iPhone, iPad, or Android smartphone's camera over the text of the magazine interviews, the device should begin streaming video of those interviews.
Note that this requires a camera, so it doesn't work with first generation iPads (like the one I own).
What do people think of this way of integrating technology into the magazine? Has anyone gotten their hands on the June 2012 issue to try it out yet? Is this the wave of the future or just a cool gimmick (or both)?
How to Transform Physics
Today I received an e-mail containing the following question:
What is the apropriate [sic] way to spread my revoloutionary [sic] message on how to transform modern physics?
When you're at all in the public eye for physics, you get these sorts of requests on a fairly regular basis. I spoke a while back about a rather deft way cosmologist Sean Carroll discussed dealing with physics cranks. Still, this particular individual was polite, so I decided to respond at length, offering some of the insights taken from Carroll's earlier comments on this topic:
Not to be glib, but if you want to have the message taken seriously by the physics community, you'll need to get a doctorate in physics, so that you have a full and complete understanding of existing physics. You can then formulate your revolutionary framework within the language and terminology of the physics community as well as craft experiments that will provide evidence for your approach over the approaches of others. For example, how does your theory account for the array of fundamental particles which have been experimentally identified, as well as their individual properties? What sort of results does your theory predict for various types of particle collisions? That sort of thing.
If you are located near a university, another (less costly) option would be to contact the physics department there and see if they have any physics seminars that are open to the public. Researchers frequently present their findings at universities and going to these things (or to a more established scientific conference, but these things tend to be more costly) will give you an idea of the amount of rigor and detail that the physics community requires in presenting their results.
Consider a timeline of the major work by Albert Einstein:
1895 - Enters the Swiss Federal Polytechnic (i.e. begins rigorous study of physics)1905 - Publishes initial inklings of special relativity, photoelectric effect, and Brownian motions; Earns PhD1915 - Completes work extending special relativity into a full theory of gravity, general relativity1919 - Observational evidence from an eclipse confirms Einstein's predictions; general relativity is largely accepted by the physics community1921 - Albert Einstein receives a Nobel Prize for his work on the photoelectric effectAt best, the argument could be made that Einstein transformed physics after 10 years of intently studying physics, but if he'd never gone further than those original inklings of special relativity he wouldn't be remembered much today. Rather it took not only another decade of work, but rather about 15 more years of active engagement by a large segment of the physics community - Max Planck, Arthur Eddington, & Hermann Minkowski spring to mind immediately - in order to transform his correct intuitions into a workable theory.
The idea that anyone today would be able to do it with less effort than this is highly unrealistic and likely misguided.
One further note: The goal of going to physics seminars should genuinely be to learn about physics, not so that you can corner some poor unsuspecting postdoctoral student and explain to him or her how you're more clever than all of the brilliant physicists that they've spent the last decade or so of their life studying. This will not work. It's fine for you to strike up conversations and build relationships with physicists, but that relationship should be built from you trying to learn what they know.?This tip from Stephen Covey's 7 Habits of Highly Effective People is useful here:
"Seek first to understand, then to be understood."
Warped Space May Create Escher-like Universe
A new theoretical model posted onto the ArXiv website by Stephen Hawking and colleagues proposes something very curious: that space may actually reflect a curious structure that has more in common with the artistic style of M.C. Escher than the smooth fabric that is often taken as the cornerstone of general relativity. As described in New Scientist (registration required):
The images in question are tessellations, arrangements of repeated shapes, such as the images of interlocking bats and angels seen in?Circle Limit IV. Although these are flat, they serve as "projections" of an alternative geometry called hyperbolic space, rather like a flat map of the world is a projection of a globe. For example, although the bats in the flat projection appear to shrink at an exponential rate at the edges, in hyperbolic space they are all the same size. These distortions in the projection arise because hyperbolic space cannot lie flat. Instead, it resembles a twisting, wiggly landscape of saddle-like hills.
Hawking - together with University of California's James Hartle - have been working on an approach to create a quantum picture of cosmology since the 1980's, and the Escher-like structure fell out of that. The problem with their approach was that the expansion of the universe seems to indicate that the universe has a positive cosmological constant, and that makes their equations unstable and fairly useless.
However, the team (also consisting of Thomas Hertog, from the Institute for Theoretical Physics at Catholic University of Leuven in Belgium) has recently realized that when a negative cosmological constant is put into the wave functions of the universe using their models, it turns out that the model can evolve over time to be very similar to a form of string theory developed by Juan Maldacena in 1997. This famous "Maldacena conjecture" stunningly linked the holographic principle to string theory and is seen by many as having the potential to translate string theory into a format that yields more direct insights, because it links a string theory model together with a quantum physics model and helps reduce the complexities arising from the extra dimensions. (Here is a link to the ArXiv copy of Maldacena's 1997 paper, for those interested in the more technical aspects.)
Hawking, Hertog, and Hartle certainly aren't done with their work ... in many ways, it creates more questions than it solves. That is, if the idea even works at all!
Already, physicist Lubos Motl has indicated on his blog that he doesn't have particularly high regard for the possibilities of this work being decisive and, in fact, it looks like possibly the calculations have been negated in his own comment thread! (Although the Hawking paper on ArXiv has been edited since then, so it's possible that the sign error he's talking about has been fixed and the paper is still there.)
The truth is that these models are sometimes introduced and get a bit of fanfare, but usually they don't really end up going anywhere ... or, if they do go somewhere, it takes years for them to get there. This model is so new that there's very little discussion of it yet, and it's through that discussion that scientists will help to determine whether or not it has any value. At present, I'm suspect, though ... and I'd urge caution from anyone before they begin declaring that our universe has some bizarre geometric structure that isn't experimentally verified!
Still, if the model could be extended and refined to match experimental data, and if it then makes predictions that could be further tested, it might represent some true progress at creating a theory that combines quantum physics with general relativity. And, if that works, then we'll have discovered that, once again, the universe really doesn't look the way that we expect it to ... and that would be a pretty neat discovery.
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