Paging Papajohn - Temperatures below absolute zero begin to get hotter?

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Beyond 'absolute zero' temperatures get hotter | TG Daily

It sounds like a contradiction in terms but scientists have reached temperatures that go beyond absolute zero in a lab, and get hotter as they do so.

Whereas we’re all aware of what happens when temperatures hit negative temperatures on the Fahrenheit and Celsius scales (hint: it gets really cold), the Kelvin scale is an absolute temperature scale in physics where it is not possible to go beyond 0 degrees Kelvin. Therefore, the lowest point that any temperature can reach is 0 K or −460 °F (−273.15 °C); at least that’s what scientists thought until till now.

When they cooled an atomic gas to extreme lows, known as ‘ultracooling’, physicists at the Ludwig-Maximilians University Munich and the Max Planck Institute of Quantum Optics in Germany created a gas that went beyond absolute zero.

They found that the atoms in the ultracooled gas attract each other and give rise to a negative pressure. Instead of standing still when they go beyond 0 K, the gas becomes hotter.

"The gas is not colder than zero kelvin, but hotter," says physicist Ulrich Schneider, lead author on the paper that is published in the journal Science.

"It is even hotter than at any positive temperature."

This strange behavior has everything to do with how energy is spread throughout the atoms in a gas known as the ‘Boltzmann distribution’. A gas at any temperature will have different amounts of energy spread amongst its atoms. In a gas that is cooled, the majority of the particles will have low energy states although a few will have higher energy states.

When the Kelvin temperatures become negative in the ultracooled gas, the distributions of energy is the opposite way round so that most of the particles have very high energy states while very few have low ones. In this case, the Boltzmann distribution is said to be ‘inverted’ so that the normal state of affairs is reversed.

“The inverted Boltzmann distribution is the hallmark of negative absolute temperature; and this is what we have achieved,” says Schneider.

Their finding suggests that the previously impossible idea of a combustion engine that is 100 percent efficient may actually be achievable. Their finding offers a tantalizing insight into how 'dark energy', the elusive force that cosmologists believe is responsible for the expansion of the universe, might work.

As the Universe should be contracting under the force of gravity, rather than expanding as measurements suggest, the authors believe that dark energy could cause the expansion of the Universe by behaving in the opposite way to what is expected from the force of gravity. In the same way that the gas particles attract each other at negative temperatures rather than being repelled, dark energy may cause the expansion of the Universe by acting as a sort of negative gravity.
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I'm 12 and what is this?
 


Explain to me like I'm five

[ame="http://www.youtube.com/watch?v=2f43-YWWv2c"]The Offce - Explain to me like im five - YouTube[/ame]
 
35hpkl1.jpg
 
WHAT'S SO CONFUSING?

A GREAT MODERN DAY PHILOSOPHER POET ALREADY TAUGHT US THAT WHEN YOU COOL AS ICE, YOU BE HOT.

[ame=http://www.youtube.com/watch?v=P9yaam0p_BA]Vanilla Ice Says It Best In Cool As Ice - YouTube[/ame]
 
Well, it's actually pretty remarkable. They've been able to get below 0 degree in physics. It's like saying, you have 2 girls and 1 cup. Then you have 2 girls 0 cups. Then you have 2 girls less 1 cup, shit just got hotter? Understand. Think about it.

LOL, but seriously, the part about using 100% combustable engines, means absolutely NO emissions. NO need for an exhaust pipe, everything gets used. Rotary engines (Mazda RX7 & RX8) spin in circles, instead of the up and down movement all other cars do. They are 66.67% energy efficient. The up and down engines (car pistons - think car oil commercials), are only 50% efficient, since they only create power on the downward movement. Understand? Now, we'll have the ability to get to 100% efficient, meaning lower gas prices, longer mileage, but that's a small tip of the iceberg. If anyone cares to correctly me if I'm wrong, be my guest, It's been a long time since I've been in a physics class.

I could go on about the important of dark energy, the reason the universe is shrinking, but also expanding, but that's going to be a little harder.

To put it in simpler terms, We are going to be more energy efficient Almost 100%, and A lot of futuristic technologies are going to come out of this. Welcome to the future.

cDB4U.gif


Carry on.

- His Excellency, Director for Life, Field Marshal Doctor Cartel Carter PhD, VC owner of WaFo & DP, Lord of All the Beasts of the Fire of Wicked and Trolls of the Darknet and Conqueror of the Google Empire on the Interweb in General and their organic rankings in Particular

P.S. Yeah motherfuckers, I actually paid attention in school.
 
CCarter said:
Well, it's actually pretty remarkable. They've been able to get below 0 degree in physics. It's like saying, you have 2 girls and 1 cup. Then you have 2 girls 0 cups. Then you have 2 girls less 1 cup, shit just got hotter? Understand. Think about it.

LOL, but seriously, the part about using 100% combustable engines, means absolutely NO emissions. NO need for an exhaust pipe, everything gets used. Rotary engines (Mazda RX7 & RX8) spin in circles, instead of the up and down movement all other cars do. They are 66.67% energy efficient. The up and down engines (car pistons - think car oil commercials), are only 50% efficient, since they only create power on the downward movement. Understand? Now, we'll have the ability to get to 100% efficient, meaning lower gas prices, longer mileage, but that's a small tip of the iceberg. If anyone cares to correctly me if I'm wrong, be my guest, It's been a long time since I've been in a physics class.

I could go on about the important of dark energy, the reason the universe is shrinking, but also expanding, but that's going to be a little harder.

To put it in simpler terms, We are going to be more energy efficient Almost 100%, and A lot of futuristic technologies are going to come out of this. Welcome to the future.

cDB4U.gif


Carry on.

- His Excellency, Director for Life, Field Marshal Doctor Cartel Carter PhD, VC owner of WaFo & DP, Lord of All the Beasts of the Fire of Wicked and Trolls of the Darknet and Conqueror of the Google Empire on the Interweb in General and their organic rankings in Particular

P.S. Yeah motherfuckers, I actually paid attention in school.
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Rotary motors are less efficient
 
BlokBlok said:
Rotary motors are less efficient
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Yes, and no. Your are correct to a degree. Rotary engines have a higher horsepower to liter (size) ratio, meaning they can be smaller and get the same amount of horsepower. But since most rotary engines are turbocharged they tend to consume more fuel than a piston engine because of the combustion-chamber's shape and low compression ratio. So by efficient, they are best in sport cars in a lightweight environment at high rpm and there is a need for higher power outputs (Racing), versus a a soccer Mom driving to the grocery store.

So they are more efficient at delivering power than a piston engine during a race. Less efficient during grocery shopping by consuming more gas, which 90% of the world needs them for anyways.

So it depends on what you need the car for. The original topic was about being 100% fuel efficient, so your absolutely right on this topic, fuel wise they consume more fuel.

I completely screwed up by causing confusion I just realized, since my explanation of rotary engines versus piston engines had nothing to do with more fuel efficiency, it was more power related since rotary engines deliver power during 3/4 of their spin, and looking up the details pistons only deliver power 1/4 of their rotation. My bad.
 
They are referring to energy efficiency, not specific output. When they say 100% efficient that means none of the energy released by the chemical reaction from combustion is lost to heat dissipation and not converted into kinetic energy and work by the engine. The air fuel mix in a combustion engine pre-combustion holds chemical energy. During combustion that energy is converted into thermal energy, then into kinetic energy by the movement of the piston (or rotor in a Wankel).

The loss of efficiency is due to friction, heat dissipation and the fact that completely stoich (14.7:1) combustion is hot as balls and not as easy on components under heavy load in your typical combustion engine and usually only seen in light-load cruising conditions. A "rich" air/fuel ratio is used under wide open throttle, usually 11.5:1-12:1 in forced induction engines and around 13:1 in naturally aspirated engines, and thus some chemical energy remains in unburned fuel. Even a 100% efficient internal combustion engine would still require exhaust as there would still be a product equal in mass to the inputs. The engine is simply turning the expansion of the combustion gases resulting from the chemical reaction into work, not removing mass.

It's important to note that they did not specify internal or external combustion engines.
 
cassius said:
thus some chemical energy remains in unburned fuel. Even a 100% efficient internal combustion engine would still require exhaust as there would still be a product equal in mass to the inputs.
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That's what my gut feel stated after I hit submit. Since the fuel is rarely ever 100% pure there would still need to be an exhaust system. Thanks for helping me out, it's been a long time since I went deep into that part of my brain.
 
CCarter said:
That's what my gut feel stated after I hit submit. Since the fuel is rarely ever 100% pure there would still need to be an exhaust system. Thanks for helping me out, it's been a long time since I went deep into that part of my brain.
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This may be potentially ignorant, but even if fuel was 100% pure, it would still require some sort of exhaust system. Energy cannot be destroyed - only converted into different forms of energy.
 
CCarter said:
That's what my gut feel stated after I hit submit. Since the fuel is rarely ever 100% pure there would still need to be an exhaust system. Thanks for helping me out, it's been a long time since I went deep into that part of my brain.
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No problem. I am a physics and automotive junky so I basically creamed my pants twice when I saw this article and the consequent discussion.

jhoffy22 said:
This may be potentially ignorant, but even if fuel was 100% pure, it would still require some sort of exhaust system. Energy cannot be destroyed - only converted into different forms of energy.
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Not ignorant at all, you are completely correct. The conservation of mass is the reason there will be an exhausted product that must be scavenged from the cylinder. The mass of the air fuel mix being combusted will be the same before and after combustion, the chemical makeup will just have changed due to the combustion reaction. Even in hydrogen combustion, where the product is water, the product (h2o) needs to be scavenged from the chamber for a clean burn in the next cycle.
 
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