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Physicists Build Circuit That Generates Clean, Limitless Power from Graphene

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Re: Physicists Build Circuit That Generates Clean, Limitless Power from Graphene

#51

Post by gus_massa »

barney54 wrote: post #47
tgsovlerkhgsel wrote: post #16

Earlier quoted context omitted.

> If this is representative of press releases from universities If you want reporting that accurately represent science, in my experience, the university press releases are even worse than the worst mainstream shit-tier media.

The incentives for the PR team is to make news. They don’t have to spend a ton of time cleaning up the mess of misleading press releases.

At some point it tarnish the reputation of the university. If your university get famous for sending ridiculous press releases, I hope that eventually the journalist will notice and just forward them to The Onion.

Re: Physicists Build Circuit That Generates Clean, Limitless Power from Graphene

#52

Post by raziel2701 »

gus_massa wrote: post #51
barney54 wrote: post #47

Earlier quoted context omitted.

The incentives for the PR team is to make news. They don’t have to spend a ton of time cleaning up the mess of misleading press releases.

At some point it tarnish the reputation of the university. If your university get famous for sending ridiculous press releases, I hope that eventually the journalist will notice and just forward them to The Onion.

That point is too far in the future for anyone currently in power to care. If that point is ever reached it would require larger numbers of the population to be scientifically literate. I don't see that happening, everything is clickbaity now.

Re: Physicists Build Circuit That Generates Clean, Limitless Power from Graphene

#53

Post by raziel2701 »

barney54 wrote: post #47
tgsovlerkhgsel wrote: post #16

Earlier quoted context omitted.

> If this is representative of press releases from universities If you want reporting that accurately represent science, in my experience, the university press releases are even worse than the worst mainstream shit-tier media.

The incentives for the PR team is to make news. They don’t have to spend a ton of time cleaning up the mess of misleading press releases.

Yup, there are no consequences for these people so why should they change? No skin in the game I tell ya.

Re: Physicists Build Circuit That Generates Clean, Limitless Power from Graphene

#54

Post by sm4rk0 »

IgorPartola wrote: post #19
ArtWomb wrote: post #18

Earlier quoted context omitted.

Only in the load resistor. Electron flux in the graphene membrane appears to be solely due to geometry. This curvature does not necessarily need to be buckled via heat energy. It could be mechanical or electrical, if I understand things correctly... More detail in this video clip with UArk's Paul Thibado: https://www.youtube.com/watch?v=wrleMqm3HiU I think what this research opens up is the possibility of "optimal" h…

This does sound promising. Is it possible to run this process in reverse a la a heat pump to create an AC with no moving parts? Or is this purely a one way process?

I'd say Joule heating is the reverse of this process: https://en.wikipedia.org/wiki/Joule_heating#Microscopic_desc...

Re: Physicists Build Circuit That Generates Clean, Limitless Power from Graphene

#55

Post by gus_massa »

ag56 wrote: post #42
gus_massa wrote: post #37

Ignoring the horrible horrible horrible title ... This can only work if there is a temperature difference between the grapheme membrane and the load resistor (the lamp in the animations). Other wise, it breaks the Second Law of Thermodynamics. The problem is not that it breaks some remark from Feynman, the problem is that if there is no temperature difference, it breaks the Second Law of Thermodynamics and in particu…

Doesn’t the article explicitly say that is not the case? > Though the thermal environment is performing work on the load resistor, the graphene and circuit are at the same temperature and heat does not flow between the two. I’m not a physicist or even an educated layman, can you explain your comment more?

I read that part a few times, but it makes no sence.

I prefer another quote

> What we did was reroute the current in the circuit and transform it into something useful.

Let's suppose that they get some "useful" energy to turn on the lamp like in the animation or power a small device.

Let's suppose that you use it to power a laser and send a beam that heat some object far away. As a side effect, you are extracting energy from the device with the graphene in the lab so it will get cooler.

So the net effect is that the device in the lab gets cooler and the object far away get hotter. So you have a flux of heat. But if the other object is hotter, you have a lux of heat from in the wrong direction, that is impossible according to the Second Law.

There are a million ways to rewrite this https://en.wikipedia.org/wiki/Second_law_of_thermodynamics in more abstract or more concrete ways. With some oversimplifications, another is that you need at least two heat baths and the efficiency of the device to transform heat from the "hot" bath to of "useful" energy can be calculate using the temperatures of the baths. When the difference of temperature is zero, the efficiency is zero and the device can produce no "useful" energy. Or in other words, with only one heath bath, you can produce no "useful" energy.

Re: Physicists Build Circuit That Generates Clean, Limitless Power from Graphene

#56

Post by wongarsu »

gus_massa wrote: post #37

Ignoring the horrible horrible horrible title ... This can only work if there is a temperature difference between the grapheme membrane and the load resistor (the lamp in the animations). Other wise, it breaks the Second Law of Thermodynamics. The problem is not that it breaks some remark from Feynman, the problem is that if there is no temperature difference, it breaks the Second Law of Thermodynamics and in particu…

At least it doesn't break conservation of energy. The second law of thermodynamics is already kind of suspect in that random fluctuations break it all the time on a microscopic level. It's closer to a statistical observation.

Turning heat into usable energy without temperature differential is still an extraordinary claim that demands extraordinary evidence, but I wouldn't dismiss it out of hand

Re: Physicists Build Circuit That Generates Clean, Limitless Power from Graphene

#57

Post by vikramkr »

gus_massa wrote: post #51
barney54 wrote: post #47

Earlier quoted context omitted.

The incentives for the PR team is to make news. They don’t have to spend a ton of time cleaning up the mess of misleading press releases.

At some point it tarnish the reputation of the university. If your university get famous for sending ridiculous press releases, I hope that eventually the journalist will notice and just forward them to The Onion.

MIT has a reputation for super sketchy press releases, but their research reputation is fine still. Even with the whole epstein scandal. I wonder how much it takes to actually tarnish their reputation.

Re: Physicists Build Circuit That Generates Clean, Limitless Power from Graphene

#58

Post by jostmey »

andi999 wrote: post #46

If the title of this post were true, the paper would have been published in nature instead.

While I share your disappointment in the quality of the press release, Nature is by no means the bar for measuring significance. I've been both accepted and rejected by Nature, I've seen colleagues accepted and rejected by Nature, and I've found results published outside of Nature, Cell, Science more reproducible!

Re: Physicists Build Circuit That Generates Clean, Limitless Power from Graphene

#59

Post by digikata »

gus_massa wrote: post #49
mannykannot wrote: post #45

Earlier quoted context omitted.

"However, there is power dissipated by the load resistor, and its time average is exactly equal to the power supplied by the thermal bath." As the "thermal bath" is supplying power, this seems consistent with it being a Carnot-equivalent heat engine. There is certainly nothing in physics that prevents the extraction of energy from an environment in which the temperature fluctuates - devices that do so to keep mechani…

The clock in your link uses the temperature fluctuations, for example if it hot during the day and cool during the night. So you can have a flux of heat from the hot part to the cold part, and extract a small part as useful energy. If we take the press release at face value, in this device there is no difference of temperature. So if the Second Law of Thermodynamics is correct it is not possible to extract some usefu…

It is difficult to tell at this level if they're claiming to have built Maxwell's Daemon out of graphene - or at least an approximation thereof.

Re: Physicists Build Circuit That Generates Clean, Limitless Power from Graphene

#60

Post by zamalek »

gus_massa wrote: post #55
ag56 wrote: post #42

Earlier quoted context omitted.

Doesn’t the article explicitly say that is not the case? > Though the thermal environment is performing work on the load resistor, the graphene and circuit are at the same temperature and heat does not flow between the two. I’m not a physicist or even an educated layman, can you explain your comment more?

I read that part a few times, but it makes no sence. I prefer another quote > What we did was reroute the current in the circuit and transform it into something useful. Let's suppose that they get some "useful" energy to turn on the lamp like in the animation or power a small device. Let's suppose that you use it to power a laser and send a beam that heat some object far away. As a side effect, you are extracting ene…

So, spooky thermocouples at a distance? This paper is one that really needs further attempts at replication.
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