## Search found 3199 matches

Sat Feb 23, 2019 2:42 pm UTC
Forum: Science
Topic: What if the second law was breakable?
Replies: 24
Views: 436

### Re: What if the second law was breakable?

A constant source of new free energy would violate the first law but not the second law, because as you said, entropy would still continue to increase. A constant source of free energy and a sink for energy should do the trick though, since you could just hook one end up to your refrigerator's power...
Fri Feb 22, 2019 5:59 pm UTC
Forum: Science
Topic: What if the second law was breakable?
Replies: 24
Views: 436

### Re: What if the second law was breakable?

I disagree that the observable universe is a universe any more than an acting president is a president. It may be all we can I observe of the universe, and he may be acting as the president, but it's not the universe, and he's just a pretender.
Fri Feb 22, 2019 2:22 pm UTC
Forum: Science
Topic: What if the second law was breakable?
Replies: 24
Views: 436

### Re: What if the second law was breakable?

A system that is not closed doesn't deserve to be called a universe.
Fri Feb 22, 2019 1:09 pm UTC
Forum: Science
Topic: What if the second law was breakable?
Replies: 24
Views: 436

### Re: What if the second law was breakable?

Well, it's not like that, because we in fact live in a universe where energy is not conserved yet entropy is nondecreasing. Energy is conserved locally, and entropy increases globally, always. It is possible to violate the second law of thermodynamics in principle (though not in practice), but it is...
Fri Feb 22, 2019 9:15 am UTC
Forum: Science
Topic: What if the second law was breakable?
Replies: 24
Views: 436

### Re: What if the second law was breakable?

Yeah, you can set up a system of particles to evolve into a lower entropy state. So if all possible initial conditions are real, then in some of them, entropy decreases. Like I said, it's a statistical law. But it is difficult to overstate just how unlikely this is, requiring the double exponential ...
Fri Feb 22, 2019 7:01 am UTC
Forum: Science
Topic: What if the second law was breakable?
Replies: 24
Views: 436

### Re: What if the second law was breakable?

I suppose in a strict sense, superdeterminism can violate the second law. And like, if we live in a teleological universe where God has already set things up in order to play out in a specific way, then there is no law of physics saying it could not have been set up to play out in a very surprising ...
Thu Feb 21, 2019 8:33 pm UTC
Forum: Science
Topic: What if the second law was breakable?
Replies: 24
Views: 436

### Re: What if the second law was breakable?

The reason Eddington (and doogly) say this is that the second law is, at its most fundamental, a purely statistical law. It is not just true because we observe it to be true but because literally just counting proves that it must be true. So in this hypothetical universe, counting doesn't work either.
Thu Feb 21, 2019 8:26 pm UTC
Topic: 2113: "Physics Suppression"
Replies: 23
Views: 1362

### Re: 2113: "Physics Suppression"

Incidentally, there is a scenario of increasing cosmological "constant" in which all particles really do get ripped away from each other into their own isolated observable universes. It's called the Big Rip. It's not a super plausible end to the universe at this point, but it's difficult t...
Thu Feb 21, 2019 8:16 pm UTC
Forum: Language/Linguistics
Topic: Regional Dialect and Idiolect Oddities (pronunciation)
Replies: 944
Views: 259566

### Re: Regional Dialect and Idiolect Oddities (pronunciation)

flicky1991 wrote:Definitely "pat-a-cake" in UK. I associate "patty-cake" with US.

Wikipedia gives "pat a cake" from 1698 and "patty cake" from 1765. As an American, I'm also familiar with the latter.
Wed Feb 20, 2019 2:15 am UTC
Topic: 2113: "Physics Suppression"
Replies: 23
Views: 1362

### Re: 2113: "Physics Suppression"

It's a nice fact to be true if you believe in eternal recurrence, I guess, though you can always find other ways for that hypothesis to be true if you really want.
Tue Feb 19, 2019 12:15 am UTC
Topic: 2113: "Physics Suppression"
Replies: 23
Views: 1362

### 2113: "Physics Suppression"

https://imgs.xkcd.com/comics/physics_suppression_2x.png Title text: "If physics had a mafia, I'm pretty sure the BICEP2 mess would have ended in bloodshed." I see this attitude all over the place, that physics is monolithic and the only reason whatever crackpot theory isn't mainstream is ...
Sun Feb 17, 2019 3:51 pm UTC
Forum: Mathematics
Topic: The frog riddle
Replies: 17
Views: 1133

### Re: The frog riddle

Similarly, if I flip a coin twice, I know that I am twice as likely to get a heads and a tails as I am to get two heads. And if I know for a fact that I will not flip two tails, I now have a 2/3 chance of flipping a heads and a tails and a 1/3 chance of flipping two heads.
Sat Feb 16, 2019 7:35 pm UTC
Forum: Science
Topic: Favorite home experiments
Replies: 589
Views: 460259

### Re: Favorite home experiments

An on-topic bump, how about that!
Fri Feb 15, 2019 12:37 am UTC
Forum: Science
Topic: Science fleeting thoughts
Replies: 191
Views: 31288

### Re: Science fleeting thoughts

The scale factor increases exponentially, which is what it means for the cosmological constant to be constant.
Thu Feb 14, 2019 7:36 pm UTC
Forum: Science
Topic: Science fleeting thoughts
Replies: 191
Views: 31288

### Re: Science fleeting thoughts

Yeah, ΛCDM is by far the best model we have so far.
Thu Feb 14, 2019 2:20 am UTC
Forum: Science
Topic: Science fleeting thoughts
Replies: 191
Views: 31288

### Re: Science fleeting thoughts

Dying in negative absolute pressure (that is, in tension) isn't so much "decompression" as being actively torn apart.
Wed Feb 13, 2019 7:44 am UTC
Forum: Language/Linguistics
Topic: Is this logical statement true or false?
Replies: 15
Views: 5595

### Re: Is this logical statement true or false?

Pfhorrest wrote:("What is?" they ask. "This", I say. "That's not an answer" they insist, but I retort "That wasn't a question").

Hoisted by their own pet aardvark
Tue Feb 12, 2019 6:32 pm UTC
Forum: Mathematics
Replies: 4
Views: 418

His answer does suggest a practical method for getting an exact answer to this problem by adjusting the individual charges until they are equal. It's not the algebraic method that the teacher probably wants and that extends to future problems, but it is a better method for solving the problem mental...
Mon Feb 11, 2019 12:57 am UTC
Forum: Language/Linguistics
Topic: Longest word with only 3 letters
Replies: 37
Views: 25052

### Re: Longest word with only 3 letters

FYI -- I know I am 4 years late, but I caught this on Google and decided to write a program of my own. It looks like either your dictionary or program didn't work quite right, btilly, because I got a longer 3-letters-only word: seeresses: 3 letters, 9 chars long. I also got another in the 8-letter-...
Sun Feb 10, 2019 7:48 pm UTC
Forum: Science
Topic: Science fleeting thoughts
Replies: 191
Views: 31288

### Re: Science fleeting thoughts

I agree with that principle in general, but I'm pretty unconvinced by this example in particular. I found the study referenced . It points out that "The only previous study of the effectiveness of Bike Ed as a teaching program was performed in Newcastle, Australia and showed that it appeared to...
Sat Feb 09, 2019 11:17 pm UTC
Forum: Science
Topic: Science fleeting thoughts
Replies: 191
Views: 31288

### Re: Science fleeting thoughts

Well, in the specific example of Maxwell, he died shortly before electromagnetic waves were discovered, that's true. But the difference is that at that time, electromagnetism had only just begun to be understood. At the present, the weak interaction is very well understood, and the picture has not r...
Sat Feb 09, 2019 11:10 pm UTC
Forum: Mathematics
Topic: The frog riddle
Replies: 17
Views: 1133

### Re: The frog riddle

It looks like you're right, he mentions it later in the video. I think the fact that it's an idealized problem is pretty clear from the outset though, even if not every assumption is stated explicitly.
Fri Feb 08, 2019 10:44 pm UTC
Forum: Science
Topic: Science fleeting thoughts
Replies: 191
Views: 31288

### Re: Science fleeting thoughts

I was just thinking about this. The only way neutrinos are "used" in the status quo is in astronomy, so the most obvious extension would be to other observational technology, especially military surveillance. I was thinking that at a minimum, it could add another independent method for con...
Fri Feb 08, 2019 6:52 pm UTC
Forum: Science
Topic: Science fleeting thoughts
Replies: 191
Views: 31288

### Re: Science fleeting thoughts

I think none of these things are relevant to that fundraiser. The only way it would make sense to talk about high energy physics at a fundraiser would be to fund research into basic physics. (Physicists do after all like to use billion dollar pieces of equipment.) But I thought Link was just musing ...
Fri Feb 08, 2019 4:20 pm UTC
Forum: Science
Topic: Science fleeting thoughts
Replies: 191
Views: 31288

### Re: Science fleeting thoughts

The electromagnetic interaction has unlimited range. The strong and weak interactions have very, very limited range. This makes them less than ideal for communication. That doesn't mean they can't be useful in other ways, though.
Wed Feb 06, 2019 1:43 am UTC
Forum: Mathematics
Topic: The frog riddle
Replies: 17
Views: 1133

### Re: The frog riddle

I will grant that from a practical standpoint, the problem doesn't really work. If male frogs always croak, then we already know the non-croaking frogs are female. If male frogs sometimes croak and sometimes don't, then a pair of males is more likely to produce at least one croak in the given interv...
Tue Feb 05, 2019 11:46 am UTC
Forum: Mathematics
Topic: The frog riddle
Replies: 17
Views: 1133

### Re: The frog riddle

As a probability puzzle, it is pretty straightforward and the narrator does a decent job of explaining it. Qaanol, the narrator says that each frog's sex is independent.
Sat Feb 02, 2019 2:06 am UTC
Topic: 1732: "Earth Temperature Timeline"
Replies: 540
Views: 107151

### Re: 1732: "Earth Temperature Timeline"

Wikipedia says difluoromethane has no risk to the ozone layer and only half the global warming potential of diclorodifluoromethane. But from what I see it looks like the range is too large to say anything meaningful. CFCs range from 4,500 to 14,000, HCFCs range from 80 to 2,000, and HFCs range from ...
Fri Feb 01, 2019 7:12 am UTC
Topic: 1732: "Earth Temperature Timeline"
Replies: 540
Views: 107151

### Re: 1732: "Earth Temperature Timeline"

The remaining elephant in the room, is of course anthropogenic. This can itself be divided into two forcings--i) the GHG forcing from primarily carbon dioxide, but also methane and chloroflourocarbons, which is positive, and ii) [...] Is the CFC contribution significant? This is actually an interes...
Thu Jan 31, 2019 2:17 am UTC
Forum: Language/Linguistics
Topic: IPA joke
Replies: 10
Views: 3962

### Re: IPA joke

OK, I don't really understand IPA very well. I admit that. I looked up "beer" on wiktionary and found this: Pronunciation • IPA(key): /bɪə(ɹ)/ • (UK) IPA(key): /bɪə/ • (US) IPA(key): /bɪɹ/ • (near–square merger) IPA(key): /bɛə/ • Rhymes: -ɪə(r) • Homophone: bier That seems wrong to me. It...
Thu Jan 31, 2019 2:06 am UTC
Forum: Mathematics
Topic: Fractions help.
Replies: 13
Views: 1373

### Re: Fractions help.

Etymonline
Wed Jan 30, 2019 2:08 am UTC
Forum: Mathematics
Topic: Fractions help.
Replies: 13
Views: 1373

### Re: Fractions help.

TIL all meanings of the English word "check" derive from terms medieval Frenchmen used in reference to or while playing chess, and thus ultimately from the Persian word "shah." I guess if a hockey player checks me, he is threatening to capture me. And if I check your coat, I am r...
Wed Jan 30, 2019 12:25 am UTC
Forum: Science
Topic: Can a thruster using geomagnetic fields and superconductors generate a thrust?
Replies: 9
Views: 1015

### Re: Can a thruster using geomagnetic fields and superconductors generate a thrust?

Not quite the same thing, but I was wondering if there was a way to turn a receiving laser beam into electricity. The device is, unfortunately, called a " rectenna ." A concept has been floating around for almost fifty years that we could put solar panels in orbit and send energy by maser...
Wed Jan 30, 2019 12:19 am UTC
Forum: Language/Linguistics
Topic: IPA joke
Replies: 10
Views: 3962

### Re: IPA joke

Yeah, "beer" is a diphthong for me for sure. Probably for everyone?
Wed Jan 30, 2019 12:14 am UTC
Forum: Mathematics
Topic: Fractions help.
Replies: 13
Views: 1373

### Re: Fractions help.

It might be true that number lines are not very useful for understanding negative multiplication, but I feel like answering the implied question anyway. Multiplying really does two things on the number line, not just one. Multiplying by a real number scales by its magnitude and reflects by its sign....
Tue Jan 29, 2019 2:00 pm UTC
Forum: Science
Topic: Consequences of climate change
Replies: 90
Views: 20282

### Re: Consequences of climate change

You need an international agreement, which is the whole point of all these agreements we were signing until something happened a couple years back.
Mon Jan 28, 2019 3:14 pm UTC
Forum: Science
Topic: "Absolute" vs "Relative" humidity
Replies: 2
Views: 339

### Re: "Absolute" vs "Relative" humidity

If I evaporate an ounce of water in a cubic yard, I have an absolute humidity of one ounce per cubic yard. It's just how much water vapor there is. Sometimes it's cold and some of that water condenses and forms dew. That means the relative humidity is above 100%. But sometimes it's hot and the water...
Mon Jan 28, 2019 2:57 pm UTC
Forum: Science
Topic: Science fleeting thoughts
Replies: 191
Views: 31288

### Re: Science fleeting thoughts

I don't think your nerves can function at all anaerobically. Apparently they can use lactate to briefly maintain ion homeostasis, during which time you would arguably be "not dead" in the sense that if all your mitochondria magically reappeared, it''s just conceivable that you could be rev...
Mon Jan 28, 2019 5:51 am UTC
Forum: Science
Topic: Science fleeting thoughts
Replies: 191
Views: 31288

### Re: Science fleeting thoughts

It would be almost immediate, even faster than cutting off oxygen to the brain.
Mon Jan 28, 2019 4:36 am UTC
Forum: Science
Topic: Science fleeting thoughts
Replies: 191
Views: 31288

They would die.