Astrophysics

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Astrophysics is a hybrid of Physics and Astronomy that attempts to explain the physical workings of the celestial objects and phenomena. Astrophysics has two subdivisions: theoretical, and applied or experimental.

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Research focus

Research in astrophysics addresses a great variety of topics,[1][2] for example:

Stars

- stellar evolution
- magnetic field properties
- stellar convection

Stellar atmospheres

- nature of spectral analysis
- electron density[3]

The Galaxy (the Milky Way)

- interstellar gas and dust

Galaxies

- modeling the environs of galactic-centre massive black holes;
- the structure and dynamics of galactic bars;
- the flow of gas into and out of galaxies;
- the role of active galactic nuclei in limiting the growth of galaxies.

CMB (cosmic microwave background radiation)

Solar neutrinos

Cosmic rays

Astroparticles

Black holes

Dark matter

Dark energy

Dark energy is a theoretical energy which exerts a negative attraction or opposes the positive attraction of matter and causes the universe to expand.[4][5]

A current line of study is surveying the distribution of galaxies in the cosmos. The distribution pattern is compared to the miniscule temperature fluctuations in the cosmic microwave background. Theoretically acoustic waves moving through the early universe created temperature fluctuations, and the fluctuations are correlated to regions of the universe that had slightly higher and lower densities. These regions of varied density are believed to have influenced how matter eventually clumped together through gravitational influences and thereby formed galaxy clusters. Comparing clumping in the early universe to clumping being observed now may possibly allow researchers to ascertain the role dark energy has played in cosmic evolution.[6]

Astrochemistry

Astrochemistry involves the study of the role of the chemical bond and organic chemistry in nature on a cosmic scale. Over 140 molecules have been identified in the interstellar gas and circumstellar shells. To date the largest is a carbon chain with 13 atoms and a molecular weight of 147.[7]

Inflation

Inflation refers to the expansion of the universe, its velocity and whether or not it is slowing or gaining in speed.[4] The Supernova Acceleration Probe (SNAP) is a space observtory planned for possible construction and launch by 2020. It is designed to measure the expansion of the Universe and determine the nature of Dark Energy which current theory holds is accelerating cosmological expansion.[8]

Curvature

Curvature refers to the shape of the universe.[4]

Notes

  1. Theoretical astrophysics Oxford Physics, Oxford University
  2. CfA Research Harvard-Smithsonian Center for Astrophysics
  3. Degenerate electron pressure Swineburn University, Centre for Astrophysics and Supercomputing
  4. 4.0 4.1 4.2 Dark energy fills the cosmos Preuss, Paul (1999). Science Beat. The Berkeley Lab, U.S. Department of Energy.
  5. [1] Cosmology with dark energy decaying through its chemical-potential contribution. Besprovsvany, J., Instituto de Física, Universidad Nacional Autónoma de México (2007). Journal of Physics A: Mathematical and Theoretical, 40 7099-7104
  6. Advanced Dark Energy Physics Telescope Beyond Einstein. National Aeronautics and Space Administration
  7. Astrochemistry Harvard-Smithsonian Center for Astrophysics
  8. SuperNova Acceleration Probe Lawrence Berkeley National Lab