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Comment Re:How would anyone be able to tell? (Score 2) 192

You know how jerky is made? You take meat, cut it into slices, then let it dry (sometimes with salt, but you can do it without IIRC if you raise the temperature a bit so it dries faster). Same with breadcrumbs: you take slices of bread, and let it sit on the counter, separated so they can dry quicker (before mold has a chance to form), and then crumble the dried bread. That's all that happened: they made McDonald's jerky and dried bread. There's probably a bit of mold near the center of the burger, where it'd take much longer to dry out, but maybe not, since the burger is relatively thin and dry to begin with. You could do a similar thing with any foodstuffs thin and/or dry enough to dry out completely before it begins to rot.

Comment Re:My thoughts... (Score 1) 387

This post is just... well, it's really just completely wrong. We have a well-established theory of the expansion of the universe, which comes naturally out of both Newtonian gravity and General Relativity (in fact, Einstein tried to modify General Relativity to avoid a non-static universe, as he thought at the time the universe had to be static. He was wrong).

Mainstream cosmology like "Big Bang" is based entirely, 100% on data that is by their own theory at the edge of what any sensor can detect and is therefore worthless based on everything we know about sensors. Sensors suck at the edges of what they can detect; all of them.

No, it's not. This is just straight up false. Mainstream cosmology is based primarily on observing the Cosmic Microwave Background and the current structure of the universe, neither of which is "at the edge of what any sensor can detect." The CMB is in fact very easy to detect (so easy, in fact, it was detected by a radio telescope by accident. It's so easy to see, if you turn on an old analogue TV, some of the static on the screen is the CMB). You can make predictions the number of neutrino species based on CMB observations. Those predictions agree exactly with results from particle accelerator experiments. You can predict the hydrogen to helium mass ratio (and the amounts of heavier elements) based on some simple thermodynamics/nuclear physics calculations. Those predictions (with the exception of the Lithium abundance) agree (again, as exactly as you can get in physics) with observations from astrophysics.

What if there is some sort of very weak force pulling on them, slowly shifting them red as they age, and we'd need a lab with a beam at least a few hundred light years long to start to detect it? We have no way of knowing what we don't know at that scale!

Actually, we do have such a lab. It's called "the universe". A few hundred light years is easy. All you have to do is look at the spectral lines of stars in our own galaxy (or distant ones, if you want to expand to hundreds of thousands of lightyears). "Tired light" has been proposed as a theory long ago, but it has not been supported by any observation.

Comment Re:Implications (Score 1) 126

That being the case, I've got to wonder exactly how insane the gravitational waves from a black hole merger are compared to the relatively steady fast-orbiting binary stars we can see via more traditional means? Are such waves theoretically too weak for us to detect with LIGO, or is it just that the signal-analysis is only looking for the distinctive "spike" from a black hole merger as a sort of low-hanging fruit to prove that gravity waves do in fact exist?

LIGO is looking for both, the problem is that such binaries don't emit a high-amplitude pulse, which is easy to see over the noise, you need to integrate over a large set of data to get a statistically significant SNR. As a result, it takes a lot more work, so they haven't published any findings on that yet.

Perhaps the more interesting question for me is, just how much will the proposed eLISA mission, with it's 250,000x longer arms (and I presume 250,000x greater sensitivity, plus much lower ambient noise levels) be able to detect? Being able to directionally detect the gravity waves from fast-orbiting binary stars, that we can then correlate with more traditional telescopy, could give us incredible insight into the workings of gravity waves including, in the case of binaries unmistakably spinning down, confirming whether the waves actually propagate at lightspeed.

While eLISA is a really cool and important next step, the advantage isn't entirely greater sensitivity (it's strain sensitivity is actually less than LIGO), it's that it can explore an entirely different frequency range of gravitational waves (think radio vs. infrared telescope: they see completely different things).

Comment Re:Where is the news? (Score 1) 247

The news is about the chips being Chinese "designed" (quotes because I don't think anyone seriously thinks they designed them from scratch), but as a side note China actually only has a dozen or so semiconductor fabs. Most fabs are in the US, with Taiwan a (distant) second (assuming that list isn't woefully incomplete).

Manufacturing only goes to China because labor there is cheap. For stuff like semiconductor fabrication, offshoring to China makes very little sense, since much of the work is automated anyways (most of the cost is in the fab itself), and what isn't requires strict quality control and skilled labor.

Comment Re:Since no one's reading his actual statements: (Score 1) 219

However Tesla's promotional material about their system is not suggesting that; their promotions are all focused on technical ability but it's ignoring the fact that if you're in an emergency the system basically tosses control to you, so his argument is that Tesla's promotion of the technology gives drivers and users the wrong impression of what it's really doing.

So, when Tesla's presskit on Autopilot states that "Tesla requires drivers to remain engaged and aware when Autosteer is enabled. Drivers must keep their hands on the steering wheel.", what exactly do you think they're doing besides exactly what you claim they're not?

What the Volve engineer is doing is touting his own system's capabilities over and above the Tesla system. He's saying "look at how much more autonomous our system is!" It's advertising, and not much more. It's yet to be seen whether the Volvo system is actually safer or not in practice. In principle, fully autonomous driving is rather obviously safer than requiring manual intervention in the case of an emergency, but it remains to be seen if the Volvo system will realize that in practice.

Comment Re:Robots? (Score 3, Informative) 866

I don't see robots doing work. I see people making pennies assembling iPhones in China, children working in sweatshops in Vietnam making Nike clothing. This man is a fool. The problem isn't robots. People are cheaper than robots are.

Because you're not looking. There's a reason the US is the second largest manufacturer in the world, and has grown in manufacturing capability over the last 15 years (except for a dip during the recession), while at the same time continueously employing fewer and fewer people in manufacturing jobs. It's called "robotics". Turns out it's cheaper in the US, where average/minimum wages are relatively high, to use robots than it is people, while in China, with it's much lower wages, it's still viable to use human labor. People are only cheaper if you live in a country with a shit average wage.

Comment Re: No reason not to make them available publicly (Score 2) 60

Why? What interest does the general population have in access to the LHC data? They've already release a subset of the data for educational purposes, in addition to this considerable data dump. It serves no public interest to make the whole data set available to everyone, and in fact would run contrary to the public interest: the data set is absolutely massive (the LHC produces petabytes of data per day), and the costs associated with making that data available to the public would be non-negligible.

If a specific individual is interested in access to the data, they're certainly free to email their local (or not even necessarily local) university department associated with the LHC and ask for it, and they could probably get access to a subset of it, if they've shown genuine interest. And by "genuine interest", I mean have already downloaded, processed, examined, and understand much of the already publicly available data, to the point where they are capable of performing actual scientific research on the data, and aren't simply interested in wasting already-precious scientific research money and time in making some kind of political or philosophical point.

Comment Re:Thanks, Summary (Score 2) 532

The first isn't very far-fetched. They definitely do have energy-derived mass as per E=mc^2, and this mass supposedly is indistinguishable from other forms of mass.

No, they don't. Energy is not mass. That equation is actually incomplete: the full equation is E^2-p^2c^2=m^2c^4. For photons, E=pc, so their mass is zero.

Now, they can contribute to the invariant mass of a system, but that's different from the photons themselves being massive, which we're almost sure they aren't, to an extremely high precision.

Comment Re:The Physics (Score 1) 53

Heat exists outside of transfer.

No it doesn't. Heat is not a well-defined thermodynamic state variable: two identical systems can have different "quantities of heat" in them. That's basically the whole idea behind a heat engine: you put thermal energy into a system, and you get out mechanical energy (and as a result you end up with less heat).

Temperature has differing, barely-related meanings as you go up and down the scale of temperatures (e.g., the temperature at the Sun's core isn't really about kinetic energy)

No, they're all pretty much the same definition, just applied to specific models. For e.g. an ideal gas assumes non-interacting particles, which becomes very non-true at high pressures and temperatures, so we use a different model to describe the Sun than we do the atmosphere in the room on the Earth. As a result, the relationship between temperature and some other quantities (like mean kinetic energy) will depend on the system in question, but that's a property of matter and it's annoying tendency to interact with other matter. Temperature is precisely defined the same in all cases, it just happens that there are usually easier-to-measure ways to find the temperature for each of those models.

Comment Re:Expected different (Score 1) 266

There's no Blizzard copyrighted material on the server,

Yes there is. The data is copied from the clients (which is why it's possible to create such servers in the first place), but the server does need a copy of them. Things like mob locations, walls, vendors, banks, etc. all need to be known to the server. That means using Blizzard data, unless you want to replicate the entire WoW map from scratch (and that would violate copyright, anyways).

Comment Re:Electrons?? (Score 5, Informative) 71

Since the past 100 years or so. They're point particles, which means they have no internal structure, and aren't composed of any other particles. They can be destroyed or created, but that's not division.

You can also split an electron's wavefunction into multiple pieces, so that it occupies certain distinct regions with various probability amplitude (and these split wavefunctions can actually have physical effects: while I'm not enough of an expert on condensed matter to say for sure, a quick skim of the paper indicates that something like that is what is happening here), that's a bit different from dividing the electron.

Comment Re:We asked for it (Score 1) 140

While it is possible, it is extremely unlikely that it collided with orbital debris. Hitomi was traveling at 575km, a relatively low Earth orbit that is not terribly debris-heavy (the Earth's atomsphere actually de-orbits debris for us, thanks to drag effects). The objects spotted in its vicinity around the time of lost contact were debris from the satellite itself. Given the relatively short period of time it was operating for, the most likely problem was a failure in one of its systems (coolant or propellant) that caused an explosion. Deeply unfortunate, but it happens from time to time.

Comment Re:Anonymous? (Score 1) 122

The goal isn't to make radar that is impossible to detect, but radar that is much much harder to detect. The former is basically impossible, the latter is quite achievable. With stealth technology it's always an arms race. Even the F-22 has some radar signature, because it's nearly impossible to eliminate it completely. The goal is simply to be as hard as possible to detect.

Comment Re:Never any description (Score 2) 107

That's not how it works. First, while once the aliens measure the polarization of the beam, they know the polarization of our beam, but we don't even know that they know that (because we can't tell if they've measure their beam or not). Secondly, once the aliens would entangle their beam with another beam, it destroys the entanglement with the original beam, which means the two things are no longer correlated. Entanglement doesn't allow you to choose the state of your system, it only allows you to know, once you've made the measurement of your side of the beam, what the other people would see if they made a measurement of the same property on their side. Nothing in entanglement (or quantum mechanics) allows instantaneous transmission of information in any way, shape, or form.

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