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Uber Will Provide Transit Data To Cities 32

Posted by Soulskill
from the how-best-to-distribute-starbucks-franchises dept.
mpicpp notes that transportation company Uber will be sharing the transit data it collects with city governments in order to "provide new insights to help manage urban growth, relieve traffic congestion, expand public transportation, and reduce greenhouse gas emissions." The company's first partnership will be with Boston, where Uber and other ridesharing services have been formally recognized by the state. Mayor Walsh said, "[D]ata is driving our conversations, our policy making and how we envision the future of our city. We are using data to change the way we deliver services and we welcome the opportunity to add to our resources. This will help us reach our transportation goals, improve the quality of our neighborhoods and allow us to think smarter, finding more innovative and creative solutions to some of our most pressing challenges."

Space Tourism Isn't Worth Dying For 594

Posted by timothy
from the all-worked-up-about-a-false-dichotomy dept.
rudy_wayne writes with this opinion piece at Wired published in the wake of the crash of SpaceShipTwo, which calls the project nothing more than a "millionaire boondoggle thrill ride." A selection: SpaceShipTwo is not a Federation starship. It's not a vehicle for the exploration of frontiers. Virgin Galactic is building the world's most expensive roller coaster, the aerospace version of Beluga caviar. It's a thing for rich people to do. Testing new aircraft takes a level of courage and ability beyond most humans. Those engineers and pilots are at the peak of human achievement. What they're doing is amazing. Why Virgin is doing it is not. When various corporate representatives eulogize those two pilots as pioneers who were helping to cross the Final Frontier, that should make you angry. That pilot died not for space but for a luxury service provider. His death doesn't get us closer to Mars; it just keeps rich people further away from weightlessness and a beautiful view.

Comment: Saving Earth's resources? (Score 2) 243

by hansraj (#48082259) Attached to: 2014 Nobel Prize In Physics Awarded To the Inventors of the Blue LED

As about one fourth of world electricity consumption is used for lighting purposes, the LEDs contribute to saving the Earth's resources.

Efficiency does not mean lower consumption. Efficiency remains a useful goal but not "to save the planet's resources". The latter can happen only if overall consumption is reduced. What will happen is that as electricity used for lighting purposes is consumed less, it will get cheaper to direct it elsewhere.

Comment: Re:Black holes are real, we observe them all the t (Score 1) 356

by hansraj (#47991121) Attached to: Physicist Claims Black Holes Mathematically Don't Exist

Maybe he should have meant the following version which seems very counter-intuitive:

Suppose you wrap a string around the Earth's equator so that it fits tightly. Now suppose you add an extra meter in the length of that string. Surely, the string won't be tight anymore. So pinch it at a point and pull it upwards as high as you can. (Now, the string goes tightly around most of the earth, and forms a triangle elsewhere with the apex being the point you pinched and pulled.)

How high this apex would be from the surface? The answer turns out to be well over a hundred meters. See Image 1

(Apart from the actual number, the surprising part is also that the bigger the initial object - earth here - the higher you can pull the string even though you add the same extra length of 1 m in each case.)

Comment: Re:Read the whole article (Score 1) 136

by hansraj (#47234057) Attached to: The Profoundly Weird, Gender-Specific Roots of the Turing Test

Also, either the author of the article has a listening comprehension problem or the assitant professor quoted in the article has a reading comprehension problem.

Look at Turing's original article. It says that the imitation game is played between a man (A), a woman (B), and a player C. C has to decide among A and B who is a man and who is a woman. Now, the _man_ is replaced is a computer and we ask if C will perform as well or poorly as before.

So in Turing's version we have a computer A pretending to be a woman to C, and a woman trying to convince C that she is the woman.

Turning's original test _does not_ have a man and a computer pretending to be a woman to a judge.


The Profoundly Weird, Gender-Specific Roots of the Turing Test 136

Posted by Soulskill
from the i'm-sorry-dave,-these-shoes-are-half-off dept.
malachiorion writes: Alan Turing never wrote about the Turing Test, that legendary measure of machine intelligence that researchers claimed to have passed last weekend. He proposed something much stranger — a contest between men and machines, to see who was better at pretending to be a woman. The details of the Imitation Game aren't secret, or even hard to find, and yet no one seems to reference it. This article explains why they should — in part because it's so odd, but also because it might be a better test for 'machines that think' than the chatbot-infested, seemingly useless Turing Test.

Comment: Re:the joker in the formula (Score 1) 686

by hansraj (#47222521) Attached to: Aliens and the Fermi Paradox

There are 7 billion people on earth but only one tallest person. Clearly the odds of finding a tallest being on any planet is 1:7_billion.

The point of parent is that if the intelligent "us" were not us, someone else would have evolved to be as intelligent. You can argue that point but don't argue probabilities based on 1 out of however many being intelligent. Two intelligent species would have competed and one would be killed off so far in earth's history.

Comment: Re:Fascinating, terrifying stuff is news (Score 1) 358

by hansraj (#47165237) Attached to: The Disappearing Universe

Do you realize that the whole point of the GP's "exercise" was that you can't ignore relativity? It is due to relativity that the time observed by the traveller would be so little. If you are travelling at a velocity very close to the speed of light, in your own frame time is essentially standing still. You would get to your destination before you could blink your eye.

Now redo the calculations taking time dilation into account.

Comment: Usual /. (Score 4, Informative) 82

by hansraj (#47145519) Attached to: Optical Levitation, Space Travel, Quantum Mechanics and Gravity

The summary (and the headline) unnecessarily highlights space travel as a usage for radiation pressure and delegates the most interesting part as a footnote-ish last line. The /. crowd as usual starts shouting pros and cons of space travel, as if every comment on this page is not saying what has already been said a million time around here, and nobody to talk about the interesting part.

I wish someone with the right background in physics posted something more interesting about the fact that a group of researchers have come up with prediction of how a non-quantized spacetime (gravity) would look in the presence of quantized matter/energy. Apparently this would look different than a quantized background with quantized foreground (IANAP, so I don't know what is this all about) in a measurable way. If they can levitate a tiny but macroscopic mirror using light and balance it then giving it a gentle push would create a pendulum with no friction slowing it down. By probing the frequency evolution one can potentially get closer to actually knowing whether a quantum theory of gravity is the right way to unify QM and GR.

It's fascinating that such things are possible even in principle with existing technology. I wish someone would explain something more related to this.

Comment: Re:Clueless (Score 1) 80

by hansraj (#47109063) Attached to: The Rule of Three Proved By Physicists

I don't think so.

Stability of ordinary matter is well explained by other more traditional theories (strong/weak forces for nucleus, electromagnetic for atoms and molecules, gravity for even larger structures). This theory described stable states that initially no one believed existed.

Morever, these configurations are stable but quite fragile.

Comment: Re:Clueless (Score 5, Informative) 80

by hansraj (#47107177) Attached to: The Rule of Three Proved By Physicists

I found the summary confusing but the article made more sense.

The theory was that there exist configurations of three particles that is stable in a strange sort of way. The strange part is that if a certain configuration was stable then putting the particles in the same configuration but the distances blown up by a certain factor (22.7 if the three particles were the same) gives another stable configuration. So you can keep blowing up the distances in multiples of 22.7 and would get an infinite sequence of stable configurations. These configurations are necessarily quantum and not classical since the distances involved would be much larger than the range of the forces between the particles. (Although even the initial distances are large too, if i understood correctly, you would agree that they _will_ get pretty large at some point).

Now some independent groups have shown the existence of such states with the required blowup. Since similar-particle setup required cooling things down to the limit of present day technology, only _one_ configuration was observed initially. Someone used a system of different particles resulting in a blowup factor less than 22.7 allowing them to observe _three_ of these configurations, essentially validating the theory.

Hope that made sense (IANAP).

Comment: What increases the risk (Score 2) 172

by hansraj (#46824935) Attached to: Asteroid Impacts Bigger Risk Than Thought

I don't think anyone is implying that we are doomed because of _these_ impacts.

However, in general the frequency of an impact event is inversely proportional to the size of the impacting body. Smaller impacts happen more often than the larger ones. Counting the smaller ones precisely gives you an idea of what the risk of a big event is.

So far people underestimated these smaller ones that is being reported. The wikipedia article I linked to earlier, suggests one impact every five years at the level of 5 kT of TNT. These guys being right would imply a risk of at least a magnitude higher than previously estimated. That increases the risk for the really big ones too.


Withhold Passwords From Your Employer, Go To Jail? 599

Posted by Unknown Lamer
from the bad-plan-with-expected-results dept.
ericgoldman writes "Terry Childs was a network engineer in San Francisco, and he was the only employee with passwords to the network. After he was fired, he withheld the passwords from his former employer, preventing his employer from controlling its own network. Recently, a California appeals court upheld his conviction for violating California's computer crime law, including a 4 year jail sentence and $1.5 million of restitution. The ruling (PDF) provides a good cautionary tale for anyone who thinks they can gain leverage over their employer or increase job security by controlling key passwords."

Comment: Re:I know what you're thinking.. (Score 4, Informative) 77

by hansraj (#41172323) Attached to: NASA Uncovers Millions of New Black Holes

A black hole would dissipate via Hawking radiation only if it doesn't absorb more energy than it emits. Large blackholes absorb more energy (cosmic background radiation) than they would emit and hence will not necessarily dissipate. From wikipedia:

"A black hole of one solar mass has a temperature of only 60 nanokelvins; in fact, such a black hole would absorb far more cosmic microwave background radiation than it emits. A black hole of 4.5 × 1022 kg (about the mass of the Moon) would be in equilibrium at 2.7 kelvin, absorbing as much radiation as it emits. Yet smaller primordial black holes would emit more than they absorb, and thereby lose mass."

"Buy land. They've stopped making it." -- Mark Twain