research-on-origin-of-primordial-black-holespbh

Context: Researchers from Inter University Centre for Astronomy and Astrophysics (IUCAA) have studied primordial black holes(PBH) that were born as a result of a tiny increase in the potential energy levels of the universe.

More about the research:

  • The study  titled as ‘Primordial Black Holes from a tiny bump / dip in Inflation potential’ was published recently in the Journal of Cosmology and Astroparticle Physics.
  • The study has confirmed that marginal rise in potential energy has resulted in the birth of several PBHs and also emitted very powerful gravitational waves.

About Primordial Black Holes (PBH) 

  • Origin:They were formed during the Hot Big Bang phase of the origin of the universe. 
  • Significance: Because of their association with Big Bang they are considered by many researchers among the principal candidates in explaining the nature of dark matter.
  • Differences with other black holes: It is believed that they are formed as a result of collapsing radiations as opposed to the collapse of massive stars, which is the case of any other black holes.
  • Extent of PBH: PBH can be massively large as 3000kms or be extremely tiny like the nucleus of an atom.

Origin of Primordial Black Holes (PBH) explained by new research:

  • Big Bang and Cosmic inflation Phase:
    • Very young universe was found to be active and expanding at a highly accelerated rate just after the big bang, nearly 14 billion years ago.
    • This exponential growth in its size, experts say, was fuelled by the presence of a uniform energy field and density as the universe passed through the Cosmic Inflation phase.
  • Association of marginal increase in the potential energy and Primordial Black Holes
    • According to the scientists, as time passes, this uniform energy prevailing in the Inflation Field wanes out. As a result of this the universe resumes its normal decelerating rate.
    • But before the energy dies out completely scientists have noticed that there could be a marginal increase in the potential energy for a very short time in the form of a bump, on to an otherwise dwindling energy-level graph. 
    • The potential energy of inflation could be higher just by 1 per cent, but could be significant enough to create vast differences in the densities.
  • Role of the repulsive gravity in rapid expansion of universe:
    • Gravity is normally attractive in nature. 
    • But according to scientists, what allowed the primitive universe to undergo rapid expansion was the Inflation field which contrarily possessed repulsive gravity. 
    • This pushed the universe to expand at a much faster rate than normal.
  • Birth of galaxies,stars and PBH:
    • Thereafter, the remnant energy possessed by this gravitational force got converted mainly into photons (light) in addition to protons, electrons, neutrons and other particles.
    • As the universe continued to grow exponentially during the Cosmic Inflation phase, it sent across tiny quantum jitters.
    • These fluctuations, released in a specific fashion, when sufficiently large, slowly give birth to galaxies and stars.
    • Among those quantum fluctuations that were significantly large, helped form PBHs.
      • Quantum is a discrete quantity of energy proportional in magnitude to the frequency of the radiation it represents.
  • Creation of strong gravitational waves:
    • The resultant bump in energy while producing PBHs also triggers very strong gravitational waves. 
    • Further studies of gravitational waves emerging from PBHs could give deeper insights as to how the energy was decaying.

About Big Bang theory

  • The Big Bang Theory is the leading explanation about how the universe began.
  • It is the idea that the universe began as just a single point, then expanded and stretched to grow as large as it is right now (and it could still be stretching).
  • The Big Bang hypothesis states that all of the current and past matter in the Universe came into existence at the same time, roughly 13.8 billion years ago. 
  • At this time, all matter was compacted into a very small ball with infinite density and intense heat called a Singularity. 
  • Suddenly, the Singularity began expanding, and the universe as we know it began.

Big Bang timeline

Source:Wiki

About Black holes

  • A black hole is a place in space where gravity pulls so much that even light can not get out. 
  • The gravity is so strong because matter has been squeezed into a tiny space. This can happen when a star is dying.
  • Because no light can get out, people can't see black holes. They are invisible
  • Space telescopes with special tools can help find black holes. The special tools can see how stars that are very close to black holes act differently than other stars.


Source:https://indianexpress.com/article/explained/explained-how-a-tiny-wiggle-in-the-young-universe-gave-birth-to-black-holes-6359411/

Image Source:IE