In other news today...
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@boomzilla said in In other news today...:
Sounds like a modern take on perpetual motion, not that I claim to understand quantum spintronics...might as well be cricket or Haskell:
It says they're utilizing temperature fluctuations, which I guess means they still need a temperature gradient, but a much smaller one than other electrical generators. Like this other thing three weeks ago it would probably change what we consider "waste" heat if it was viable.
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@LaoC said in In other news today...:
It says they're utilizing temperature fluctuations, which I guess means they still need a temperature gradient, but a much smaller one than other electrical generators.
Hmm, I interpreted (probably incorrectly) the "room temperature" part as being able to work from the existing gradients in normal conditions, i.e. like Maxwell's demon.
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@LaoC Well, we'd need to know about the efficiency-to-cost ratio in order to get a better idea whether it's worth pursuing this. Usually the efficiency is directly dependant on the incline of the temperature gradient so I'm not terribly optimistic.
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@topspin said in In other news today...:
@LaoC said in In other news today...:
It says they're utilizing temperature fluctuations, which I guess means they still need a temperature gradient, but a much smaller one than other electrical generators.
Hmm, I interpreted (probably incorrectly) the "room temperature" part as being able to work from the existing gradients in normal conditions, i.e. like Maxwell's demon.
Yeah, the article is pretty poorly written and tends to sound like that.
@Rhywden said in In other news today...:
@LaoC Well, we'd need to know about the efficiency-to-cost ratio in order to get a better idea whether it's worth pursuing this. Usually the efficiency is directly dependant on the incline of the temperature gradient so I'm not terribly optimistic.
That's hopefully (otherwise there is nothing to report) the invention—not being limited by the Carnot cycle efficiency.
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@Bulb said in In other news today...:
That's hopefully (otherwise there is nothing to report) the invention—not being limited by the Carnot cycle efficiency.
Well, there's a bit of a problem with that:
The Carnot cycle can be thought of as the most efficient heat engine cycle allowed by physical laws.
And since the Carnot Cycle can be derived directly from the 2nd law of thermodynamics...
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@LaoC said in In other news today...:
@boomzilla said in In other news today...:
Sounds like a modern take on perpetual motion, not that I claim to understand quantum spintronics...might as well be cricket or Haskell:
It says they're utilizing temperature fluctuations, which I guess means they still need a temperature gradient, but a much smaller one than other electrical generators. Like this other thing three weeks ago it would probably change what we consider "waste" heat if it was viable.
Yes, that was my understanding of the theory behind it at a high level.
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@Rhywden said in In other news today...:
@Bulb said in In other news today...:
That's hopefully (otherwise there is nothing to report) the invention—not being limited by the Carnot cycle efficiency.
Well, there's a bit of a problem with that:
The Carnot cycle can be thought of as the most efficient heat engine cycle allowed by physical laws.
And since the Carnot Cycle can be derived directly from the 2nd law of thermodynamics...
For statistical thermodynamics yes. Question is whether the quantum thermodynamics allows a better cycle. If not, this is basically pointless and the only real way to achieve high efficiency remains not going through thermal energy at all (i.e. direct chemical→electrical and similar transformations).
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Sun then adjusted the code to fix the glitch, which had to do with how different operating systems sort files.
LOL
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“We all kind of assume that a computer program always spits out the correct answer.”
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As I am fond of saying when bugs are raised at work: "It is working as coded"
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@Dragoon so basically Bing is worth $-17,000?
The median price of giving up video streaming services like YouTube for a year is $1,173.
Sure, that’s why I immediately bought YouTube premium or whatever it’s called. Not.
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@Bulb said in In other news today...:
For statistical thermodynamics yes. Question is whether the quantum thermodynamics allows a better cycle.
It doesn't. A Carnot cycle is already unattainable because every process is not entirely reversible and will increase entropy.
Unless you're claiming that sticking "quantum" on something somehow overrides some of the most fundamental laws of empirical physics...? Because quantum thermodynamics still addresses/is bound by the second law of thermodynamics.
Just wondering if you're aware that arguing with thermodynamics puts you directly into nutjob territory? For future reference.
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@acrow said in In other news today...:
@loopback0 said in In other news today...:
The garage is
As has been 'd above. If you'd like to Jeff my thread category awareness mishap there, be my guest.
You would be willing to vouch for
me@loopback0 to become a mod? How daring!
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@acrow said in In other news today...:
Who names these things?
The person who named the city, perhaps?
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@kazitor said in In other news today...:
Just wondering if you're aware that arguing with thermodynamics puts you directly into nutjob territory?
I am not arguing thermodynamics. I just didn't know whether the individual-particles level might allow any way around it or not—the key definitions are only applicable at macroscopic scale and I never studied how it relates to the particle scale—and the only way the article might live up to the hype was if such a way existed.
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@kazitor said in In other news today...:
Just wondering if you're aware that arguing with thermodynamics puts
youTFA directly into nutjob territory? For future reference.FTFY. They're the ones who claim they can harvest energy from ambient heat "at room temperature", which kinda implies no temperature gradient, so being better than the Carnot cycle is the premise of this discussion. Hence all the skepticism. The only reason it's even discussed here seems to be because it's been published on phys.org, which has a reputation of not being too nutjob-y.
That said, I can't see any a priori reason why the laws of statistical thermodynamics would have to apply to quantum thermodynamics. The "fundamental laws of thermodynamics" were established based on observations of macroscopic ensembles of particles, so claiming that these imply any microscopic properties is like claiming that there can be no quantum superposition on the particle level because we haven't ever observed superpositions on macroscopic scales.
Of course, all the research I've ever heard of seems to indicate that the laws of thermodynamics also hold at the microscopic level (including any physical realization of Maxwell's demon, apparently). Still, dissing new research results only because they seem to contradict previous research is not very scientific IMHO.
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Here's why I'm so sceptical of claims of efficiency gains through utilisation of waste heat: if you want to make a thermodynamic cycle more efficient, you put stuff within the cycle; you don't stick something on the tail-end of "heat out".
Here's the basic Rankine cycle:
Heat enters the cycle at the left, work is extracted via the turbine at the top and supplied to the pump at the bottom, and unavoidable waste heat is deposited out the right.
There are multiple ways to increase the efficiency of this cycle; for instance, reheating the working fluid after expansion:
As it is more efficient, there will be less waste heat. But that is not because the waste heat that leaves the cycle is being used in another cycle to do work.
Waste heat that leaves the cycle is invariably in a form that isn't useful. Look to improve the cycle rather than salvaging energy from a 10-degree difference at the end.
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@ixvedeusi said in In other news today...:
@kazitor said in In other news today...:
Just wondering if you're aware that arguing with thermodynamics puts
youTFA directly into nutjob territory? For future reference.FTFY. They're the ones who claim they can harvest energy from ambient heat "at room temperature", which kinda implies no temperature gradient, so being better than the Carnot cycle is the premise of this discussion.
TFA contains the sentence:
The team's experiments and analyses show that it is possible to assemble an electrical generator that utilizes the electron spin to harvest thermal fluctuations at room temperature.
Note "thermal fluctuations": they're utilising a momentary temperature gradient.
Still, dissing new research results only because they seem to contradict previous research is not very scientific IMHO.
- Hence I said "empirical physics". Extraordinary claims require extraordinary evidence, and thermodynamics is so fundamental to our understanding of the world that it would take a lot to explain those phenomena in any other way.
- I have never disputed that article in any way. I'm just arguing about Carnot efficiency and waste heat (which isn't mentioned in the article) again, weeks later.
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@kazitor said in In other news today...:
TFA contains the sentence:
The team's experiments and analyses show that it is possible to assemble an electrical generator that utilizes the electron spin to harvest thermal fluctuations at room temperature.
Note "thermal fluctuations": they're utilising a momentary temperature gradient.
Wouldn't that mean they are really building a Maxwell's daemon?
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@kazitor said in In other news today...:
@ixvedeusi said in In other news today...:
@kazitor said in In other news today...:
Just wondering if you're aware that arguing with thermodynamics puts
youTFA directly into nutjob territory? For future reference.FTFY. They're the ones who claim they can harvest energy from ambient heat "at room temperature", which kinda implies no temperature gradient, so being better than the Carnot cycle is the premise of this discussion.
TFA contains the sentence:
The team's experiments and analyses show that it is possible to assemble an electrical generator that utilizes the electron spin to harvest thermal fluctuations at room temperature.
Note "thermal fluctuations": they're utilising a momentary temperature gradient.
Yeah, but what about the inevitable reverse gradient?
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@Dragoon said in In other news today...:
You wait until they find out how many published studies are flawed due to issues in Excel...
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@dkf said in In other news today...:
You wait until they find out how many published studies are flawed due to issues in Excel...
Or FDIV.
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@Bulb said in In other news today...:
Maxwell's daemon
/etc/rc.d/init.d/maxwell start
Edit: Or this?
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@ixvedeusi said in In other news today...:
That said, I can't see any a priori reason why the laws of statistical thermodynamics would have to apply to quantum thermodynamics. The "fundamental laws of thermodynamics" were established based on observations of macroscopic ensembles of particles, so claiming that these imply any microscopic properties is like claiming that there can be no quantum superposition on the particle level because we haven't ever observed superpositions on macroscopic scales.
That is my very layman understanding of the second law, too: high entropy states are exponentially more likely than low entropy states. The Law of Large Numbers together with extremely large numbers will make violating the second law virtually impossible.
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@PJH said in In other news today...:
@Bulb said in In other news today...:
Maxwell's daemon
WP certainly spells it “demon”, but given the slightly different meanings listed in dictionary, the “daemon” spelling seems to be actually more appropriate, because it has less of the evil connotation, and Maxwell's daemon is not evil, just possesses presumably impossible powers.
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A family who spent nine years in a basement "waiting for the end of time" have been discovered by police in the Netherlands after the eldest son turned up at a local pub, reports say.
A man, 58, and his six children - aged 16 to 25 - were living at a farm in the northern province of Drenthe.
They were found after the son ordered beer at a bar in the nearby village of Ruinerwold, and then told staff he needed help, broadcaster RTV reported.
Witnesses said the man looked confused.
His family had been living in isolation waiting for the end of time, RTV reported.
"He ordered five beers and drank them. Then I had a chat with him and he revealed he had run away and needed help... then we called the police," bar owner Chris Westerbeek told the broadcaster.
He added: "He had long hair, a dirty beard, wore old clothes and looked confused. He said he'd never been to school and hadn't been to the barber for nine years."
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Rectifiers and hope?
More seriously this isn't actually relying on temperature gradients at all. There are a few surprising results using quantum in the thermodynamics space(you can turn heat into light under certain very restrictive conditions and increase entropy, for example), but I'm filing this one under 'won't work, but won't work for really interesting reasons that have yet to be discovered'.
In theory warm magnets produce high energy matching-spin electrons and low energy opposite-spin electrons. If you allow all the electrons with up spin through one door and all the electrons with down spin through another, more electrons will go through the low-energy door and the two doors will have a voltage between them.
It's maxwell's daemon, but with electrons and magnets.
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One squirrel will have to do without food this winter after its stash was found:
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"Let us out!"
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@JBert In that same vein: "Let me out!" — joking from beyond the grave. Check the article for a video
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Unlike competing services such as Netflix, Bell has yet to add a 4K streaming tier to Crave.
Crave is available on desktop, iOS, Android, Apple TV, Samsung Smart TVs, Xbox One and Amazon Fire TV. There is not yet a Crave app available on the PlayStation 4.
Crave’s base subscription is priced at $9.99 per month, with the service’s additional HBO tier costing an addition $9.99. This brings the monthly cost for Crave to a total of $19.98 per month. Users can also add STARZ content can also be added for $5.99 CAD.
So in summary, it:
- costs more than Netflix and Amazon Prime combined, at least if you want to watch HBO shows
- doesn't have 4K
- doesn't have a PS4 client
- doesn't have 5.1 yet, apparently with a small handful of exceptions on 4th-gen Apple TV
e: Also, Mobilesyrup desperately needs an editor. "Users can also add STARZ content can also be added"
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@Dragoon said in In other news today...:
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@hungrier said in In other news today...:
Also,
Mobilesyrupevery online "news" service desperately needs an editor. "Users can also add STARZ content can also be added"FTF"J"I2019
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@Boner
People in the north of the Netherlands are weird
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@Luhmann in the north. Sure.
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@Dragoon So if you want to copy a genuine chip, all you need to do is get a genuine chip, then build some flash memory that reports the same pattern the genuine chip does. By, say, hammering the cells that need to be fucked until they're fucked. In fact you could do that to thousands of counterfeit chips at once.
And that's if you want to actually test it really works as a storage device as well. Given the hardware that runs wear-leveling algorithms inside stuff like this, why not just build a chip that reports 'are you counterfeit' 'no'.
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Um... what?
*googles*
Okay... So, in other news last month...
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@JBert said in In other news today...:
What are they doing to prevent people from intentionally pooping to collect these?
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@Zecc said in In other news today...:
@JBert said in In other news today...:
What are they doing to prevent people from intentionally pooping to collect these?
Wait, hold up, humans are publicly defecating in order to obtain a little flag?
What a astounding world we live in...
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@Tsaukpaetra You know what I meant, but I approve your post regardless.
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@Zecc said in In other news today...:
@Tsaukpaetra You know what I meant, but I approve your post regardless.
I was curious, since there's a small following of feti-- well, I'll just say my curiosity has been momentarily satisfied...
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@PJH That's not a massive bag of dildos. More like an average bag of dildos.