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Comment Re:Wait a sec (Score 2) 772



Strongly disagree.
Scientific Theory: A set of equations with associated explanation in words, stating in mathematics and natural language how something works, able to make predictions supported by observation.
Scientific Law: Outdated term for a particularly well-tested Theory. Not used outside of historical naming due to the difficulty in defining "particularly well-tested".
Scientific Hypothesis: An idea of how something might work, with a way to make or test predictions. If its predictions are tested and shown to be correct it will become a theory, otherwise it will be revised or abandoned.

This is still incomplete, since there are some "tool" theories of imaginary worlds (such as Super Yang-Mills) that are not able to make predictions of the real world, but which can make certain calculations for the theories that do make predictions of the real world easier. These might better be considered mathematical theories, but they're almost all used only in physics so they tend to get lumped with the scientific theories.

Also note that, even in biology, theories involve mathematics.

Comment Re:Games: Autosave is the devil (Score 1) 521

First, because with many games that can reduce the challenge, which is seen as bad. EG save after you win each sub-stage of a boss fight, etc. Personally, I find it rather silly; either let me save wherever I want (manually) or don't let me save at all (a la roguelikes.)

Comment Re:Winston... (Score 1) 153

Unicode works, but only a small number of characters, due to the use of a whitelist. People were doing strange things with RTL control characters, hiding posts, rewriting parts of the page above, etc, so instead of blacklisting the RTL characters and languages that use them they whitelisted a tiny tiny subset of Unicode. This is of course another terrible idea. The whitelist is never updated. The preview code doesn't seem to use the same list.

Comment Re:Drone? (Score 1) 151

Because the phrase drone is scary. It invokes imagery of the military's drones, of weddings bombed and people dead. So instead of calling things RC aircraft like they used to people can call them drones, thereby scaring people and getting page views (and thus money) or political influence.

Personally, I think the definition of "drone" should be restricted to aircraft with a remote pilot (or no pilot) capable of some fully autonomous operation. So while a 747 has an autopilot it's not a drone because it has a pilot in the cockpit, and an RC plane isn't a drone because it can't do anything autonomously.

Comment Re:Worth exactly what? (Score 1) 104

Moore's law doesn't help.

Take Bremermann's Limit. With all the computing power available on Earth right now, assuming it actually doubles every year (instead of simply new computers coming out every 18 months which have double the power) then it will still take more than a few thousand years to do the computation. If someone converts the entire earth into a computer operating at the limit, then simply using a 512-bit key with symmetric algorithms will effectively fix the issue, since the time to brute-force the keyspace (10^72 yrs) is longer than the expected lifetime of the universe.

The Landauer limit is somewhat stronger, but may not be correct. Let's assume we have a good cryptosystem that uses a 256-bit key, with no attack better than brute force. Let us also assume that the Landauer limit is correct (it very probably is) and there is a minimum energy to perform a computation. To break such a cipher with a 256-bit key takes a worst-case time of 2^256 with an average case of 2^255.

Let's assume we're running our cracking computer at the coldest temperature ever produced, 100pK. Then it would take 9.67x10-34 J per operation. Let's pretend we can try a key with only one operation, since in reality it will take a few more but we should be correct to an order of magnitude. It therefore takes 2256*9.57x10-34 J = 1.1081x1044 J to brute force the key space, or about 5.5x1043 J in the average case. The average type 1a supernova puts out about 1.5x1044 J. It's about as much energy as we could get by covering the entire earth (including the oceans) with solar panels and using it all... for 20,000,000,000,000,000,000 years. Even with exponential growth we won't hit the Landauer limit for thousands of years.

So having a better random stream and being more resistant to cryptanalysis is more important than being resistant to increased computing power. It's far easier to use a side-channel attack than to directly attack the crypto, and far easier to attack the crypto than to brute-force the key.

Comment Re:Why the hell... (Score 3, Informative) 59

It's being marketed as a medical device, and the FDA also has authority over medical devices. They approve things like MRI machines and EKG machines to ensure they actually work as advertized. Also, this one is apparently capable of using electromyogram electrodes, which may be intramuscular (needles implanted into the muscles) and not just those attached to the skin.

Comment Re:simulating a phenomena does not validate the mo (Score 4, Informative) 129

If there are no parameters for a model that allow the model to simulate reality, then the model must be incorrect.
If there are parameters for a model that allow the model to simulate reality, then the model may be correct, but may still be incorrect.

This work moves us from the first state to the second, at least when it comes to simulating rather large scale structure.

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