宇宙をフィラメントで照らす
1Institute for Computational Cosmology, Durham University, South Road, Durham DH1 3LE, UK. liang.gao@durham.ac.uk
Science (New York, N.Y.)
|September 18, 2007
まとめ
最初の星は宇宙の糸で形成され,その性質は暗黒物質に依存していた. これは金属が少ない星と超大質量ブラックホールの種を説明するかもしれない.
科学分野:
- コスモロジー・コスモロジーとは
- 天体物理学 天体物理学
- 素粒子物理学 素粒子物理学について
背景:
- 最初の星の形成は,初期の宇宙における重要な出来事である.
- 恒星形成を理解するには,暗黒物質の性質の知識が必要です.
- 分子水素 (H2) は,恒星形成のための原始ガスの冷却に重要な役割を果たします.
研究 の 目的:
- 最初の星の形成と特徴に暗黒物質の性質の影響を調査する.
- 初期の恒星形成と超大質量ブラックホールの起源の間の潜在的な関連を探求する.
主な方法:
- 初期の宇宙の条件をモデル化するために,高度なスーパーコンピュータシミュレーションを使用します.
- ダークマターのハロの中で,化学的に純粋なガスの重力崩壊をシミュレートします.
- ダークマターの粒子速度が構造形成に与える影響を分析する.
主要な成果:
- ダークマターの性質は,最初の星の性質を決定的に影響する.
- 小規模構造を消去する速度を持つ温暖な暗黒物質候補は,線状恒星形成につながります.
- フィラメントの断片化により,質量が異なる恒星が生成され,非常に金属が少ない恒星における観測された元素の豊富さを説明する可能性がある.
結論:
- 最初の星の特徴は,暗黒物質の性質と密接に関連しています.
- シミュレーションで形成された線状構造は,初期の恒星群を理解するための枠組みを提供します.
- これらの構造の崩壊は,最初の超大質量ブラックホールの種を蒔くための経路を提供しているかもしれません.
関連する概念動画
01:35Light as Energy
The energy required to carry out photosynthesis is light— typically electromagnetic radiation from the sun. The range of all possible wavelengths is known as the electromagnetic spectrum.
Photons
A photon is a discrete electromagnetic particle or bundle of energy. Photons are characterized by their frequency, wavelength, and amplitude, similar to the properties of a wave. Waves with higher frequencies transmit more energy and have shorter wavelengths than longer wavelengths that transmit less...
Photons
A photon is a discrete electromagnetic particle or bundle of energy. Photons are characterized by their frequency, wavelength, and amplitude, similar to the properties of a wave. Waves with higher frequencies transmit more energy and have shorter wavelengths than longer wavelengths that transmit less...
02:12The Wave Nature of Light
The nature of light has been a subject of inquiry since antiquity. In the seventeenth century, Isaac Newton performed experiments with lenses and prisms and was able to demonstrate that white light consists of the individual colors of the rainbow combined together. Newton explained his optics findings in terms of a "corpuscular" view of light, in which light was composed of streams of extremely tiny particles traveling at high speeds according to Newton's laws of motion.
02:39Emission Spectra
When solids, liquids, or condensed gases are heated sufficiently, they radiate some of the excess energy as light. Photons produced in this manner have a range of energies, and thereby produce a continuous spectrum in which an unbroken series of wavelengths is present.
02:45Nuclear Fusion
The process of converting very light nuclei into heavier nuclei is also accompanied by the conversion of mass into large amounts of energy, a process called fusion. The principal source of energy in the sun is a net fusion reaction in which four hydrogen nuclei fuse and ultimately produce one helium nucleus and two positrons.
A helium nucleus has a mass that is 0.7% less than that of four hydrogen nuclei; this lost mass is converted into energy during the fusion. This reaction produces about...
A helium nucleus has a mass that is 0.7% less than that of four hydrogen nuclei; this lost mass is converted into energy during the fusion. This reaction produces about...
01:19The Structure of Intermediate Filaments
The intermediate filaments are one of three widely studied cytoskeletal filaments. They are so named as their diameter (10 nm) is in between that of microfilaments (7 nm) and the microtubules (25 nm). These filaments are highly stable and can remain intact when exposed to high salt concentrations and detergents. These filaments are responsible for providing stability and mechanical support to the cells. They also help in cell adhesion and maintaining tissue integrity.
Intermediate filaments...
Intermediate filaments...
00:57Formation of Intermediate Filaments
Intermediate filaments are cytoskeletal proteins with higher tensile strength and flexibility than microfilaments and microtubules. Unlike the other two cytoskeletal proteins, intermediate filament formation lacks the enzymatic activity to hydrolyze nucleotides like ATP and GTP to generate energy for polymerization. Therefore, the formation of intermediate filaments is multistep self-assembly. The involvement of any accessory proteins in intermediate filament formation has not yet been reported.