Scientists say they have discovered one of the strangest substances in the universe, a super-dense, friction-free fluid that apparently defies the laws of physics.
They found this stuff in a neutron star 11,000 light-years away.
Astrophysicists studying the center of Cassiopeia A, a neutron star that went supernova about 330 years ago, say they believe its core is composed of a rapidly cooling, unbelievably dense soup of frictionless neutrons and superconducting protons.
Science teaches us that matter comes in solid, liquid and gaseous states. Super-fluids, at least those created in a lab, aren’t bound by friction and can exhibit strange properties, including the ability to flow up and out of glass containers.
A neutron star is the ultradense core left behind after a supernova. A supernova happens when a massive star collapses at its core and releases a blast of energy that blows off its outer layers. Such a collapse can produce a black hole or its more visible cousin, a neutron star.
“Neutron stars are the densest matter that has never disappeared, beyond our universe, which is what black holes are” -Craig Heinke.
Densely packed neutron stars are made up mainly of neutrons and cause matter to behave in strange ways that can’t be studied on Earth. It was discovered last year that the neutron star inside Cassiopeia A was cooling. It is about 2 million C on the outside and had cooled by about four per cent over 10 years. Rapid cooling was noticed by a team of Mexican scientists and this must mean the neutron star contains a superfluid, an unusual state of matter that has “some really funky effects,” Heinke said.
“If something is a superfluid, that means it flows without any friction whatsoever,” explained Heinke. “So a normal river flowing along will have friction with the lake and it will cause turbulence and eddies and whatnot. A superfluid can flow without any friction.”-Craig Heinke.
That state is only seen on Earth at very cold temperatures. Liquid helium can become a superfluid if it is cooled to a temperature slightly above absolute zero, or about -273 C..
“If you have some water in a teacup, a little bit of water will kind of move up the edges of the teacup, just a little bit. It stops because it’s kind of running into some friction as it’s going (up) and that takes away its energy. The superfluid runs into no friction so it can actually flow up the side of the teacup and around (the edge) down and onto the base and then flow off your table and onto the floor. So the superfluid helium can’t be contained in a container if it’s got an open top. The top has to be closed, and very tightly.”
Neutron stars are so extremely dense that a superfluid would form inside such a star at a much higher temperature, somewhere in the hundreds of millions of degrees. Along with the superfluid inside Cassiopeia A, the neutron star also contains a superconductor with a frictionless flow that keeps its charged particles moving. “So it becomes a perfect electrical conductor, and that means that if you run a current through it, that current will never cease, it will never have any resistance,” .
“Similarly to superfluidity, superconductivity happens when you get below a certain temperature.”
Superconductors have been observed on Earth in extreme cold, around -100 C, he said. “So a really cold day in Antarctica is the highest temperature we’ve known for a superconductor, until now,” he said.
“This is actually the first time that we have evidence of a superconductor in the cores of neutron stars”, that’s really cool.
A neutron star is so dense that a teaspoon of its matter would have a mass of about six billion tones. “Another way of putting it is that if you took all the humans, all seven billion of us or so on the planet, and squashed us down until we squished into the size of a sugar cube, that’s the density of a neutron star.”
Its amazing that this is the first time we’ve been able to figure aout something and its still amystery and brings in so many questions for applications that it boggles the mind. Just think about it, if we get to one day understand this we might have great discoveries for power and we could depend less on Power reactors that produce so much toxic waste and fossil fuels.
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