Tuesday, 26 March 2013

Beberapa Misteri dalam Cosmology dan General Relativity

"Pangkat ukur pupulasan, banda ngan ukur titipan; nyawa ukur gagaduhan. 
Tetela jeung rumasa, manusa tuna kaboga"
 ~Piwuruk Urang Sunda~

Begitu terbatasnya pengetahuan dan kekuatan manusia dalam menguak tabir rahasia alam semesta raya, kita adalah makhluk yang lemah. 

Masih terdapat ribuan bahkan juta'an ketidaktahuan kita akan semesta ini.

Penulis mencoba memaparkan beberapa hal yang masih menjadi pertanyaan hingga sekarang dalam bidang Kosmologi dan Relativitas Umum Einstein.

Cosmic inflation
Is the theory of cosmic inflation correct?, and if so, what are the details of this epoch? What is the hypothetical inflaton field giving rise to inflation? If inflation happened at one point, is it self-sustaining through inflation of quantum-mechanical fluctuations, and thus ongoing in some impossibly distant place?
Horizon problem
Why is the distant universe so homogeneous, when the Big Bang theory seems to predict larger measurable anisotropies of the night sky than those observed? Cosmological inflation is generally accepted as the solution, but are other possible explanations such as a variable speed of light more appropriate?
Future of the universe
Is the universe heading towards a Big Freeze, a Big Rip, a Big Crunch or a Big Bounce? Or is it part of an infinitely recurring cyclic model?
 Gravitational wave
Can gravitational waves be detected experimentally?
Baryon asymmetry
Why is there far more matter than antimatter in the observable universe?
Cosmological constant problem
Why does the zero-point energy of the vacuum not cause a large cosmological constant? What cancels it out?
Dark matter
What is dark matter? Is it related to supersymmetry? Is the mass that makes up the dark matter halos around galaxies made up of the lightest form of supersymmetric particle (LSP)? Do the phenomena attributed to dark matter point not to some form of matter but actually to an extension of gravity?

"No guns, no killing"
~The Dark Knight~
Dark energy
What is the cause of the observed accelerated expansion (de Sitter phase) of the Universe? Why is the energy density of the dark energy component of the same magnitude as the density of matter at present when the two evolve quite differently over time; could it be simply that we are observing at exactly the right time? Is dark energy a pure cosmological constant, or are models of quintessence such as phantom energy applicable?
Dark flow
What is the cause of a large swath of galaxy clusters all moving towards one part of the universe?
Ecliptic alignment of CMB anisotropy
Some large features of the microwave sky, at distances of over 13 billion light years, appear to be aligned with both the motion and orientation of the Solar System. Is this due to systematic errors in processing, contamination of results by local effects, or an unexplained violation of the Copernican principle?
Shape of the Universe
What is the 3-manifold of comoving space, i.e., of a comoving spatial section of the Universe, informally called the "shape" of the Universe? Neither the curvature nor the topology is presently known, though the curvature is known to be "close" to zero on observable scales. The cosmic inflation hypothesis suggests that the shape of the Universe may be unmeasurable, but since 2003, Jean-Pierre Luminet et al. and other groups have suggested that the shape of the Universe may be the Poincaré dodecahedral space. Is the shape unmeasurable, the Poincaré space, or another 3-manifold?
"Semoga kami semua dijadikan manusia-manusia yang selalu dapat mengambil hikmah dan kebijaksana'an tatkala merenungi ayat-ayat Semesta-Mu"

Thanks to:

1. Bpk. Dr. rer. nat. Muhammad Farchani Rosyid, M.Sc.
2. Bpk. Dr. rer. nat. L.T. Handoko, M.Sc.
3. Kak Handika Satrio Ramadhan, M.Sc., Ph.D.
4. Kak Khalid Fatmawijaya, S.Si.
5. Kak Iqbal Robiyana, S.Pd.
6. Kang Anton Timur Jaelani, S.Si.


1. http://astrophysicsblogs.blogspot.com/2012/03/unsolved-problems-in-physics-part-i.html
2. Wikipedia
3. http://arxiv.org/

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