Science

calvinhobbes

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Here's a bit of parody:

[video=youtube;21ph1t1-qe4]https://www.youtube.com/watch?v=21ph1t1-qe4[/video]
 

CraigB

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Don't Google image search female penis.

Edit: After reading it, of course it's in Brazil.
 

IceBone

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CUORE: The Coldest Heart in the Known Universe

The CUORE collaboration at the INFN Gran Sasso National Laboratory has set a world record by cooling a copper vessel with the volume of a cubic meter to a temperature of 6 milliKelvins: it is the first experiment ever to cool a mass and a volume of this size to a temperature this close to absolute zero (0 Kelvin).

http://www.interactions.org/cms/?pid=1034217
 

bone

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What happens when you lick it? :p
 

narf

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For instance, Rosch and his colleagues have calculated that whereas clouds of atoms would normally be pulled downwards by gravity, if part of the cloud is at a negative absolute temperature, some atoms will move upwards, apparently defying gravity4.
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chaos386

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It bugs me that they describe it as being "below" absolute zero, because that's misleading. Negative temperatures are hotter than positive ones, in the sense that heat would flow out of the negative temperature system into one with a positive temperature. A more accurate description would be to think of a number line:

<--negative infinity, -3, -2, -1, 0, 1, 2, 3, infinity-->

But instead of the negative end being to the left of the positive end, you pick it up and tack it onto the right side:

+0, 1, 2, 3, infinity--><--negative infinity, -3, -2, -1, -0

Now positive infinity is pretty much the same thing as negative infinity, and +0.000001 is super far away from -0.000001. This all seems strange, because we usually think of temperature as average energy or motion of particles, but the temperature they're talking about in the article is dQ/dS, AKA "how much energy do I need to add to increase the entropy of something by a fixed amount?" Temperature goes up as you add energy, because you get diminishing returns. For most stuff, the story ends there, but if you limit your system in such a way that there is a maximum amount of energy it can hold, once you've filled it up about half way, it turns out that adding more energy starts to decrease your entropy (microstates, yo), and you've suddenly made the slope of your energy/entropy line (AKA temperature) go negative. Fill it to the max, and you're at that "-0" spot on the temperature line.
 

the Interceptor

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The universe is fucking huge!!!

No news there as such, but how huge is huge? I was bored today and calculated how long it would take us to travel from our solar system to the nearest star, Proxima Centauri. It is 4.24 lightyears away from us. Given we would travel at the highest speed a manmade object has ever achieved, which were the 252,492 km/h of the space probe Helios 2, this journey would take about 18,123 years. And this is just to the nearest star! So given we never discover interstellar travel by bending space, the chances of humans ever making it out of the solar system and reaching anything worthwhile are ... slim.

Even the speed of light becomes pale when you consider astronomical distances. Case in point: a very nice video I found which shows a photon travelling away from our sun in real time:

 
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IceBone

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nvm, hours and years.

The Interceptor just divided the distance in km by the speed, which gives 159 million hours, which is 18 thousand years.
 
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