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Kalyan Roy

SPACE.com -- New Physics? Fundamental Cosmic Constant Now Seems Shifty - 1 views

  • Recent observations of distant galaxies suggest that the strength of the electromagnetic force – the so-called fine-structure constant – actually varies throughout the universe. In one direction, the constant seemed to grow larger the farther astronomers looked; in another direction the constant took on smaller values with greater distance.
  • If confirmed, this revelation could reshape physicists' understanding of cosmology from the ground up. It may even help solve a major conundrum: Why are all the constants of nature perfectly tuned for life to exist?
Janos Haits

Astrophysics - 2 views

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    Useful category breakout for astrophysics papers at Arxiv.
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    Astrophysics (since Apr 1992)
Kalyan Roy

Why Are Quark Stars So Strange? : Discovery News - 1 views

  • First things first, neutron stars, quark stars and black holes are all born via the same mechanism: a supernova. But each of the three are progressively more massive, so they originate from supernovae produced by progressively more massive stars. So, what if a star exploded, producing something a little too massive to be called a neutron star? Well, neutron stars resist collapsing under their own gravitational pull by a characteristic of matter known as neutron degeneracy. This produces an outward force called neutron degeneracy pressure. What if the neutron star born after a supernova is too massive for this neutron degeneracy pressure to hold up against the neutron star's own gravity? In this case, it's up to the quarks that make up the neutrons to take over, preventing the body from collapsing any further. Single neutrons are composed of three quarks (two "down" quarks and one "up" quark). When quark degeneracy pressure kicks in, a quark star may be produced; the free "up" and "down" quarks get converted into "strange" quarks. Therefore, a quark star (also known as a "strange star") is made up of strange matter.
  • Using what we know from the Standard Model of particle physics, a massive quark star may have enough gravitational energy to start 'burning' strange matter. The quarks inside the core of the quark star may be abused so badly by gravitational pressure that the quarks will be converted into pure energy and neutrinos.
  • The fascinating thing with this scenario is that the quark star matter will be so dense that even the neutrinos cannot escape. However, this release of energy and generation of neutrinos creates an outward pressure countering the relentless inward gravitational pull.
  • ...2 more annotations...
  • Dai calls this extreme strange matter-burning quark star an "electroweak star"
  • Saving the best till last, the electroweak star's core would therefore be as extreme as the universe was only 10-10 seconds (that's 0.0000000001 seconds) after the Big Bang. These extreme objects would be like mini-Big Bang laboratories, maintaining a pressure where the electromagnetic and weak forces are so intertwined, they cannot be distinguished.
Kalyan Roy

New Hubble Pictures Suggest Milky Way Fell Together - Science News - 2 views

  • A preliminary analysis of elderly stars in the Milky Way appears to strike a blow against the prevailing theory of galaxy formation. The study suggests that several large and seemingly disparate chunks of the Milky Way galaxy formed at the same time from the collapse of a single blob of gas and dust.That’s in direct contrast to the leading galaxy-formation scenario, which holds that the Milky Way and other galaxies began small and grew bit by bit for the most part, gravitationally acquiring intergalactic gas and dust and merging with galaxies in their immediate neighborhood.
David Corking

New Particle Collider Operating in Secret - NYTimes.com - 0 views

  • "We may not have created a black hole, but it seems we may have discovered a way for elementary particles to shape the path of evolution. You just never know what you are going to find"
    • David Corking
       
      I am no arbiter of humour, but I think this April Fool prank is fairly lame (unless there is truth in the unlikely twitter rumour that the NYT was pranked)
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    Large Hadron Collider investigative journalism
David Corking

Warning: Gravity is "Only a Theory" by Ellery Schempp - 0 views

  • Anti-gravity papers are routinely rejected from peer-reviewed journals, and scientists who propose anti-gravity quickly lose their funding. Universal gravity theory is just a way to keep the grant money flowing.
    • David Corking
       
      Pull no punches!
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    Thanks for posting this, Joseph. Very funny!
Maluvia Haseltine

Integral satellite disproves dark matter origin for mystery radiation - 0 views

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    More holes in the dark matter hypotheses
Astro Biology

Know How Origin of Earth's survived when Oxygen has Abundant - 0 views

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    We all are aware of the fact that billions of years ago, there was very little oxygen on Earth to breathe. Scientist of University of California at Riverside (UCR) have researched when in Earth's history oxygen may have abundant. Curious to know how origins of Earth survived?
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    We all are aware of the fact that billions of years ago, there was very little oxygen on Earth to breathe. Scientist of University of California at Riverside (UCR) have researched when in Earth's history oxygen may have abundant. Curious to know how origins of Earth survived?
Sandra Flores

Star Formation - 0 views

Heated gas stream at a cool star formation?In the inner regions of a galaxy cluster, astronomers found by Michael McDonald from the Massachusetts Institute of Technology in the USA further evidence...

stars cosmos astronomy

started by Sandra Flores on 02 Nov 14 no follow-up yet
Sandra Flores

Surface and core of the Earth in its sights - 0 views

Surface and core of the Earth in its sightsOn September 10, the Russian Plesetsk cosmodrome to be brought from the ESA GOCE satellite into orbit to determine the gravitational field and the referen...

started by Sandra Flores on 05 Jan 15 no follow-up yet
Sandra Flores

13th constellation Ophiuchus - 0 views

Why is the 13th constellation Ophiuchus no longer used?The constellation Ophiuchus is often referred to as the 13th Zodiac constellation because the sun is staying in between 30 November and 18 Dec...

started by Sandra Flores on 05 Jan 15 no follow-up yet
Sandra Flores

Pictures of Exoplanets - 0 views

Are there direct pictures of exo-planets?It has exoplanets in a few cases with observations already able to prove directly, but if you can actually call the "photos" of exoplanets these recordings,...

started by Sandra Flores on 05 Jan 15 no follow-up yet
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