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Scientists Create Rare Fifth Form of Matter in Space

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Re: Scientists Create Rare Fifth Form of Matter in Space

#12
post #5

There are way more than five phases of matter...

Please do educate us.

The Bose-Einstein condensate that the article talks about is one of many low-temperature states. There are a few kinds of high-energy states too... the most famous ones being electron degenerate matter (found in white dwarfs) and neutron degenerate matter (found in neutron stars).

I think a good starting point is here: https://en.wikipedia.org/wiki/State_of_matter

Re: Scientists Create Rare Fifth Form of Matter in Space

#13
post #12

Earlier quoted context omitted.

Please do educate us.

The Bose-Einstein condensate that the article talks about is one of many low-temperature states. There are a few kinds of high-energy states too... the most famous ones being electron degenerate matter (found in white dwarfs) and neutron degenerate matter (found in neutron stars). I think a good starting point is here: https://en.wikipedia.org/wiki/State_of_matter

Better link (which was found in your link):

https://en.wikipedia.org/wiki/List_of_states_of_matter

Re: Scientists Create Rare Fifth Form of Matter in Space

#14

Here's the Wikipedia article on laser cooling: https://en.wikipedia.org/wiki/Laser_cooling Its explanation is a bit too surface level for me. Anyone have more details on the mechanism used for this experiment? Would they have used Doppler cooling like is sometimes done on Rb-85?

Author here. Yes, Doppler Cooling is the first step used in the experiment, in a Magneto Optical Trap [0]. It is followed by Polarization Gradient Cooling [1] to overcome the Doppler limit. Atoms are still way too "hot" after this step, so they are then transferred to a purely magnetical trap and cooled down further via forced evaporation [2].

[0] https://en.wikipedia.org/wiki/Magneto-optical_trap

[1] https://en.wikipedia.org/wiki/Sisyphus_cooling

[2] https://en.wikipedia.org/wiki/Evaporative_cooling_(atomic_ph...

Re: Scientists Create Rare Fifth Form of Matter in Space

#15

Here's the Wikipedia article on laser cooling: https://en.wikipedia.org/wiki/Laser_cooling Its explanation is a bit too surface level for me. Anyone have more details on the mechanism used for this experiment? Would they have used Doppler cooling like is sometimes done on Rb-85?

Author here. Yes, Doppler Cooling is the first step used in the experiment, in a Magneto Optical Trap [0]. It is followed by Polarization Gradient Cooling [1] to overcome the Doppler limit. Atoms are still way too "hot" after this step, so they are then transferred to a purely magnetical trap and cooled down further via forced evaporation [2]. [0] https://en.wikipedia.org/wiki/Magneto-optical_trap [1] https://en.wiki…

Thanks!!
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