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Comment: Re:How on earth (Score 1) 128

by jouassou (#45332529) Attached to: New Framework For Programming Unreliable Chips

I can imagine a couple of applications of these transistors though...

Many numerical simulations require repeated random sampling of some process, and then combine the results in the end. If you're averaging some billion simulations, the result should be quite robust to fluctuations in the results of each simulation. Thus it might well be worth it to use 10 billion unreliable transistors instead of 1 billion reliable transistors, if they cost the same.

Another application could be to generate random numbers. Let's say that you have a pseudorandom number generator with periodicity N, and your unreliable transistors makes the algorithm do a random jump after an average of N/100 numbers. Wouldn't that be "random enough" for more applications than just the pseudorandom number generator itself?

Comment: Cult vs. Religion (Score 2) 321

by jouassou (#45163309) Attached to: Scientology's Fraud Conviction Upheld In France

France regards Scientology as a cult, not a religion

A second woman claimed she was forced by her Scientologist employer to undergo testing and enroll in courses, also in 1998. When she refused she was fired.

It shouldn't matter whether it's a cult or a religion; if someone got fired for not undergoing religious courses and testing, that should be treated the same way by the law.

Comment: Re:I don't think encoding/decoding are fundamental (Score 1) 182

by jouassou (#45079341) Attached to: When Does the Universe Compute?

DIVIDED BY ZERO. No thank you. I'll stick with good old Newtonian physics until you idiots come up with something that accurately explains the laws of motion AND magnetism.

Sticking to Newtonian mechanics because the math looks prettier doesn't sound very scientific. Isn't the point of science to explain and predict the largest number of phenomena, with the smallest number of independent assertions?

Special relativity predicts and explains many phenomena that Newtonian physics doesn't, and even more so for general relativity. The same goes for quantum mechanics and quantum field theory, which can be used to derive all of chemistry and electromagnetism, and is the only theory so far that can predict what happens in particle accelerators. I'm not saying that any of these theories will never be superseded, but so far they explain a lot more than the theories we had in the 1800s.

Comment: Re:I don't think encoding/decoding are fundamental (Score 4, Insightful) 182

by jouassou (#45076841) Attached to: When Does the Universe Compute?

Actually, he's right, and the analogy is quite good too. Newtonian physics is "wrong" in the sense that it doesn't hold for very massive, very fast or very small objects. However, for medium-sized objects moving at medium speeds, it holds very well.

Similarly, the second law of thermodynamics, that entropy always increases, can be derived in statistical mechanics by assuming that there are an infinite number of particles in your system. Thus, it holds for the entire universe, and it holds extremely well for any macroscopic system that I know of. However, for microscopic systems, it becomes quite probable that entropy decreases in small periods of time (the fluctuation theorem tells you the probability for this to happen.)

If you're interested in how this "makes sense": in statistical mechanics, it is shown that entropy is actually just a measure of microscopic disorder. There usually exists a lot more of possible disorderly states than orderly states for a system, so if no particular microstate is preferred (the probability of entering any microstate is equally probable), it's simply more probable that you will observe a transition from an ordered state to a disordered one, not the other way around. For a small system, the discrepancy is small, so you see transitions in both directions on small enough timescales. But as the number of particles in the system grows, the number of disordered states of the total system will grow far faster than the number of ordered states (the discrepancy is O(n!) for n particles in the system), so transitions from disordered to ordered states become extremely unlikely.

Comment: Re:All biological systems... (Score 5, Insightful) 40

by jouassou (#43827081) Attached to: Advanced Biological Computer Developed

Why is it that every time foreign people do something amazing, someone has to question them about the actions of their governments?

Someone in Isreal did science? But they oppress the Palestinians, so it doesn't matter.
Someone in Saudi Arabia did science? But they oppress their women, so it doesn't matter.
Someone in China did science? But they censor their internet, so it doesn't matter.
Someone in Russia did science? But Putin is a fascist, so it doesn't matter.

Assuming that you're american, how would you react if you published a scientific paper after making a great breakthrough, and people started asking why you killed all those people in Afghanistan and Iraq, and why you tortured them without due process at Guantanamo Bay?

Don't get me wrong, I do support human rights; but you shouldn't blame every single individual for the actions of their government.

Comment: Re:Getting so tired of this "instantaneous" BS (Score 1) 364

Special Relativity makes quite clear that if two particles are spacelike separated when measured, that the concept of "instantaneous" is devoid of meaning.

From TFA:

Eisenberg emphasizes that even though in relativity, time measured differently by observers traveling at different speeds, no observer would ever see the two photons as coexisting.

So the separation was timelike, not spacelike.

Comment: Re:Spectrum allocation (Score 1) 88

When observing the universe, you want radiation to pass through the atmosphere unaltered. When communicating on Earth, you want radiation to bounce off the atmosphere. So I would guess that the best frequencies for doing radio astronomy, are actually terrible for terrestrial communication :)

Comment: Re:Talk about forgetting your password! (Score 4, Interesting) 104

by jouassou (#43451385) Attached to: Passthoughts, Not Passwords: Authentication Via Brainwaves

Since when is "works correctly 99% of the time" good enough for an authentication system?

It isn't. But it is an interesting proof-of-concept, which shows that using passthoughts as identification is actually possible.

One interesting thought would be to combine passthoughts with other authentication technologies. Imagine walking up to a door that first performs face recognition and retina scans to determine who you appear to be. The system then accesses a database of passphrases associated with your user, displays a random one on a screen, and asks you to read it out loud. The system then uses a combination of voice recognition and brainwave scans to check if you're really who you appear to be.

Although all these technologies currently have suboptimal success rates, they might yield good security if you combine them.

Comment: Re:having said that (Score 1) 127

by jouassou (#43129857) Attached to: Physicists Discover 13 New Solutions To Three-Body Problem
Depends on what you mean with completely wrong. There is a class of numerical algorithms called Symplectic Integrators, which make sure that energy is conserved. You can also choose algorithms with an adaptive stepsize, which means that the simulation should converge to within a given error tolerance. (The simulation can still suffer from e.g. accumulated floating point errors, though.)

The classic example of a simulation gone completely wrong, is the Flying ice cube problem...

Comment: Re:Always take backup (Score 1) 266

by jouassou (#42880951) Attached to: 71 Percent of U.S. See Humans On Mars By 2033

After each of those events, Earth was still more hospitable to life than any other known planet.

Life will probably survive, but I doubt that it will be human life. For instance, what survived the event 65 million years ago was not the dinosaurs that at the time dominated the Earth, but small creatures like cockroaches and rodents.

We might have the technology to travel to Mars (barely), but we have no precedent for creating a sustainable environment for supporting life.

At present, no. But if we don't try, we will never know if it's possible.

Given the choice between staying on Earth and riding out a cataclysmic event or trying to survive on another planet without outside supplies, the rational choice is to stay put.

There are more than enough people that want to stay on Earth, but projects like Mars One have already gotten over 1000 volunteers for a one-way mission to Mars. I think the rational thing is to do both.

Comment: Re:Always take backup (Score 1) 266

by jouassou (#42871395) Attached to: 71 Percent of U.S. See Humans On Mars By 2033

If that happens [a supernova goes off] the people on mars will have even less of a chance than everyone on earth because of the thin atmosphere.

That's true... To be safe from gamma ray bursts or nearby supernovas, we'll need to colonize other stellar systems. But the first step towards leaving our solar system, will be to leave our planet. And there are still lots of calamities that could affect Earth, but not Mars; supervolcanoes, pandemics, wars, asteroid impacts, etc.

How will a colony that depends on earth for survival be any sort of backup?

I agree, a backup should not depend on Earth for survival. That's why our long-term goal should be to create a self-sufficient colony with local mines, power plants, factories (the new 3D printers seem promising), greenhouses, etc. The colonial population needs to exceed around 200 residents to prevent long-term inbreeding; but if Mars One succeeds, we can reach that limit in about 100 years.

You talk about terraforming but that will literally take thousands of years if it can be made to work at all.

Are you sure about that? There are already polyextremophile bacteria and microorganisms on Earth that can withstand cold, drought, low pressure and radiation; see this and this for examples. Wouldn't it be possible to gene-manipulate these to perform photosynthesis, and breed them in laboratories to survive in a martian climate? In that case, we can ship them off to Mars, and let evolution do the rest. Sure, it'll take a while, but it's a good start.

FORTRAN rots the brain. -- John McQuillin