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Comment We can't tell. Perhaps it's a trade secret. (Score 1) 337

There have been several recent announcements by relatively reputable companies that they will soon be building and selling a fusion generator. The details are a trade secret, so we can't reasonably evaluate them. All we can really say is "Somewhere between 5 years and 30^n years.". Perhaps it's a trade secret. They may be building a working reactor right now. Details are secret.

The skepticism above is quite reasonable, but the current crop of rumors differs significantly from prior "sort of" promises. Perhaps this time it's real. Don't hold your breath.

OTOH, it *WILL* require a special mixture of hydrogen isotopes. Different groups are making different promises, and I'm skeptical not only about each of them, but also about all of them. OTOH, I'm not denying it. Skeptical means I'm not going to stop doubting them until I see proof, it doesn't mean I believe they're lying (or even wrong).

Comment Re:Mission accomplished (Score 1) 337

It wouldn't necessarily be that expensive. You just need to redefine your goals. Suppose you build it to supply power to orbiting satellites. That cuts down the size of the plant and limits the requirements for power transmission. For extra credit imagine you could use it to power probes to outlying planets, asteroids, etc. You can still use a pretty low powered maser (IIUC, microwave power absorption works better than light frequencies. Possibly because it hard to build really small antennas.)

Design it to be modular, so you can add on additional generation as needed. This allows all of your other launches to be lighter, as they no longer need to carry along large power supplies. Just enough batteries to act as ballast for when they're out of site of the power station. (Well, human occupied satellites would still need more power capabilities, but then they need lots of other special support, too.)

You certainly shouldn't design your first SPSS with the intention of powering the planet. That would be foolish.

Comment Re:Is quantum mechanics a theory? (Score 1) 205

Sorry, I never worked out the math. I did talk to a physics grad student about the concept (of refactoring the equations to put all of the distortion into time) and he said it was valid. I was never an advanced math student, and tensors baffle me, so I'm not the person to work out the math. I just throw out the idea from time to time to see if someone else will develop it.

But I do think it would work.

Comment Re:All bullshit (Score 1) 249

1) you're assuming that the argument is based on shame. My actual argument was based on potential economic cost. The shame concept could work either way. (It can be pretty expensive to raise a kid, though. And not only in direct costs.)

2) you're assuming that I'm contemplating only official complaints. I have a very hard time imagining a teen going to the police and saying she was raped unless coerced by her family.

That said, I still expect that the official claim of rape would be quite rare wrt even actual rape (especially if you count sexual contact induced by sufficient alcohol [etc.] to render acquiescence illegitimate). I believe that such statistics as are available (poor) validate my belief. Look up "date rape". Also "rohypnol".

Comment Re:All bullshit (Score 1) 249

To be fair, girls have more reason to lie afterwards than boys do. I would guess that they deny having been willing much more often than boys do, whether or not the population sampled was willing.

That said, in a "he said, she said" argument, you shouldn't believe either of them. You need additional evidence. Which is what the jury decided.

Comment Re:This seems to give FTL communication (Score 1) 205

No, you can't detect whether an electron is entangled or not. More correctly, you can't detect what it is entangled with since, IIUC it's always entangled with SOMETHING. This is actually one of the things that makes it difficult to do the experiment, as keeping the electron from shifting what its entangled with is difficult. (Actually, different characteristics of the electron can be entangled with different targets.)

Every interaction between particles yields an entanglement, you just can't usually figure out what is entangled with what along what characteristic. So we treat known entanglement as something special. What's special is not the entanglement, it's that we know.

OTOH, I am not a physicist. If I have this wrong, perhaps someone more knowledgeable will correct me.

Comment Re:Is quantum mechanics a theory? (Score 1) 205

Actually I worked for awhile on a variation of that, but it depends on the presence of mass slowing time, so that particles experience a slight preference to end up in slower time than in faster time. You've got to rewrite the equations to describe space as flat, and all the bending to be handled by variations in the speed of time (WHAT???, but yes). I was assured that this was a reasonable and valid thing to do. I never did learn enough quantum theory to try to convert this into a general theory of gravity, but I think it would work.

But that's just mechanism. Mechanism can't answer "why?". Why demands an agent with a purpose. So the real answer is that English doesn't properly describe the universe, and implicitly attributes to various things characteristics that they don't have. (It may not just be English, perhaps it's a part of the essential human thought process. That kind of assumption could be an asset in detecting a lurking predator.)

Comment Re:Is quantum mechanics a theory? (Score 1) 205

There *are* interpretations of quantum mechanics which *do* explain the "meaning" of the equations. (I'm guessing that's what you mean by "why".) Unfortunately there are several different interpretations that are consistent with the math. My favorite is the Everett-Graham-Wheeler multiworld model, but it's not the only alternative, and so far there seems to be no way to choose between them. But there are only a few interpretations, so most possible ideas of how things could work, and what it all means, are incorrect.

E.g., if you hypothesize that some god is running things, you need to presume that he's systematically interfering with the experiments (or that he just created the universe 3 seconds ago complete with all internal evidence of consistency). If you do, that is consistent with quantum theory. But it's not a very useful interpretation, as it doesn't allow you to make any predictions. Another useless theory is "When the universe happened to come into being, it was set with a series of values that specify everything that is ever going to happen down the the sub-atomic level from the first instant of existence until the final end. That can be made consistent. (Actually, that one is useful if you combine it with a theory that the simplest possible set of constraints was used.)

The multiworld hypothesis basically says that the universe splits with every quantum interaction, and you move forwards into all of the results with a probability density that reflects the probability of the quantum events involved. At the high level that we interact with things that translates into "an honest die has a 1/6 chance of coming up with a 6". So it's one of the useful interpretations. And the Copenhagen interpretation basically says "Shut up and calculate. No explanation is possible.". Most working physicists prefer the Copenhagen interpretation, because it makes things simpler (without changing the math). There are others. Look up "implicate order" for example.

Comment Re:Wait, physics doesn't work either? (Score 1) 205

I'm not sure I consider those replications, as they are all using the same equipment, and if there were a systematic problem, then there might well be a systematic effect.

OTOH, this is, essentially, a replication of experiments done previously, with a couple of added features, and it's results are consistent with those prior experiments. *THAT* I do consider a replication.

Given the nature of publishing, the study that confirms this one will also need to have some changes. It shouldn't be that way, but journals won't print *mere* replications, you've got to have some extension.

Comment Re:Comparison? (Score 1) 251

Not absolutely not true, but overstated version of an actual effect.

If the new drug is a combination of two drugs that have previously been approved, the testing required is quite minimal. AND it's deemed worthy of a brand new patent. Witness all the combination drugs that used to come as a mixture of aspirin and something, but are not either acetaminophen and something or ibuprofen and something. The trick is to time things so that you introduce the new drug slightly before the patent runs out on the old drug, and then you remove the old drug from the market, so nobody can buy it anymore (and yet, no competitor can make it). This really annoys me because acetaminophen does me almost no good.

Comment Re:Comparison? (Score 1) 251

If you place CS under business administration, don't be surprised if the results are flakey. Usually, however, CS is placed under Math, and occasionally under Electrical Engineering. Those CS departments usually do a good job and produce real results.

If you place CS under the school of business, blame the school, not the discipline, for the results you get.

Comment Re:Comparison? (Score 1) 251

There are different kinds of experiment on groups with different definitions. Sometimes (usually) it is appropriate to view the results as only applicable to some "cohort" (meaning 2). The question is "how broad is that cohort?".
coÂhort ËkÅËOEhÃrt/ noun
noun: cohort; plural noun: cohorts
        1. an ancient Roman military unit, comprising six centuries, equal to one tenth of a legion.
        synonyms: unit, force, corps, division, brigade, battalion, regiment, squadron, company, troop, contingent, legion, phalanx
        "a Roman army cohort"
        2. a group of people banded together or treated as a group.
        "a cohort of civil servants patiently drafting legislation"

Comment Re:Priorities (Score 1) 84

Some hams who were present to aid communication with families outside the area reported that their antennas were destroyed without reasonable explanation. So one may guess that aiding communication was not their priority. Also, IIRC, some doctors were shot at by law enforcement while attempting to provide medical assistance, so that probably wasn't their priority either.