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Comment Re:Obligatory Responses (Score 1) 453

Those are all good points. The larger tesla battery actually costs around 30k to make. However, due to the pr, use in alternate markets afterward, and subsidies, it is sold at a ridiculous discount to the consumer of around 12k. It's an insane deal for the consumer from a price standpoint, yet still is too expensive - it's the absolute worst part of a car that is otherwise close to engineering perfection. At least in a tesla I exoect them to hold their value so a 12k replacement every 10 years isn't too bad. Now a leaf is another story as that's 6-8k on a far cheaper econobox electric.

Comment Re:Obligatory Responses (Score 1) 453

Well that battery sediment does have merit. It basically wipes out any savings over gasoline vs electricity as you wind up paying roughly the same cost per mile, but in a massive chunk instead of distributed over every purchase. It also may have a negative enviornmental impact as when the vehicle gets 8-10 years old no one may want to buy it as the cost of replacing the battery is too close to the total cost of the vehicle. It will be interesting to see what happens to the market for used electrics in the next few years as mainstream vehicles age.
that said the total maintance cost of electrics is less than gas/diesel. It's just that it probably dosent cover the added cost of the up front cost of electrics, making them more expensive for the same performance; except for maybe the tesla, it's an excellent car sold at a loss to the company - i just hope they don't lose enough money doing that to go under.

Comment Re:Obligatory Responses (Score 1) 453

This is Slashdot. Any discussion of electric cars must include these obligatory posts - "My daily commute is 762 miles. Therefore, electric cars are useless to anyone and everyone." (Variation also acceptable: "Twice a year I drive 600 miles to Phoenix. Therefore, electric cars are useless to anyone and everyone.") "My electric power comes from coal, therefore all electric cars are more polluting than my Grandpa's 1978 Oldsmobile Cutlass."

Yes it's true how the range argument isn't true for everyone, but has been a limiting factor for at least a percentage of use cases and buyers. At least now that problem is becoming less and less important every year as batteries become cheaper for a higher energy and power density.
Also its true that coal powered electric cars pollute quite a bit, roughly the equivelant of 50-60mpg in many areas of the USA and in some areas like India 20-30, or china 30-40, while areas like Finland its 120+. So it is important to understand how physics and reality work if you really do want to have an enviornmental impact, in many areas you are better off buying a hybrid vehicle, efficient gas/diesel, or electric and supplementing it with a robust solar installation.
Honestly i see electric cars as superior technology overall, the only real thing holding them back from being superior in every way is the battery. Once that component gets close to the energy density of gasoline at a reasonable price there wont be a need to foist these on anyone, people will want them because they are better in every category.

Comment It stings... (Score 1) 161

Prézeau’s work is particularly stinging for me, because about a decade ago, as a graduate student, I was asked by my advisor to consider this problem, which I did. But in my analysis, I only considered the effect that the passing dark matter would have on the planet’s velocity, not of the density enhancement in the planet’s wake.

Ya man i know what you mean. I almost solved a quantum formula for gravity myself as my advisor asked me to solve a similar problem. But all i did was use formulas like mg(h2-h1)=E and assumed frictionless spherical cows.

Comment Can't solve a captcha but can drive just fine (Score 1) 154

I am still not sure how people think computers can deal with the real world when my 3 year old can out do most any computer in solving visual word captchas. We give them lidar and sensors galore, then painstakingly and manually map out the routes to inch resolution marking every driveway, road sign and stop light. Many of these sensors won't function in bad weather like rain and snow, and what happens when real world things happen like a blowing cardboard box that lidar would pose a far bigger threat to safe AI driving than a human driver or to a vehicle. What we need isn't really more powerful hardware or even sensors - we need groundbreaking research in new algorithms and ways to optimally fuse them. I would feel far safer in a vehicle with algorithms on par with common household fly using just two crappy cameras and a 3 dollar 6-axis gyro/accelerometer.

Its a great start if auto companies take full responsibility, i just have no hope of it actually replacing human drivers on open roads anytime in the next 20 years.

Comment Just plain short sighted (Score 1) 378

While there are serious technical problems with traveling to nearby star systems in only a few years of ship time allowing feasible travel, there are no such limitations for our solar system. It's not even revolutionary technology either it's simply better ion drives and habitat aboard the ship. There are plenty of reasons to explore or settle there, say the moons of Jupiter/Saturn or in the asteroid belt which are behind mars. Hell, its likely to occur in under a hundred years - nearby stars it isn't so clear.

Comment Re:Information is lost (Score 1) 152

Yes it's an interesting result that should point the way for more definitive study. The notion of the singularity is not well defined and may be more of a layered structure than a boundary that applies to all particles at all times ever to fall in. It would be interesting in an actual test case as the sonic approximation model suggests entanglement is preserved for higher frequencies but does rely on many (interesting) assumptions.

Comment Re:Information is lost (Score 1) 152

If you read the paper information is not lost

In conclusion, thermal Hawking radiation stimulated by quantum vacuum fluctuations has been observed in a quantum simulator of a black hole. This confirms the prediction of Hawking regarding spontaneous pair production in the presence of a horizon. This has implications beyond the physics of black holes, as it confirms the semiclassical step toward the understanding of quantum gravity. The Hawking spectrum is observed, as are the correlations between the Hawking radiation exiting the black hole and the partner particles inside the black hole. These correlations are surprisingly narrow in position space, which implies that the high frequency tail of the distribution of Hawking pairs are entangled. On the other hand, the overall weakness of the correlations in position space implies that the low frequencies are not entangled. The entanglement confirms that there is an issue of information loss within the semiclassical approximation.

Comment Re:So.. for a non-physicist (Score 3, Informative) 152

To offer a simple explanation no it cannot send information faster than light. You can have these instant correlations but as the latest research actually shows, the values are truly random until measurement. So you can send these entangled photons and unpack one at one location and another at a second remote location and know you have the correlating bit but without knowing what that is, which must be sent classically, you have no idea what is being sent. Moreover currently i know of no experiment that preserves entanglement after measurement so you must also wait classically for the particles to arrive before taking the instant correlation measurement.

Numeric stability is probably not all that important when you're guessing.