物质

Multi tool use物质是一個科學上沒有明確定義的詞,一般是指靜止質量不為零的東西。物质也常用來泛稱所有組成可觀測物體的成份[1][2]。
所有可以用肉眼看到的物體都是由原子組成,而原子是由互相作用的次原子粒子所組成,其中包括由質子和中子組成的原子核,以及許多電子組成的電子雲[3][4]。
一般而言科學上會將上述的複合粒子視為物質,因為他們具有靜止質量及體積。相對的,像光子等无质量粒子一般不視為物質。不過不是所有具有靜止質量的粒子都有古典定義下的體積,像夸克及輕子等粒子一般會視為質點,不具有大小及體積。而夸克和輕子之間的交互作用才使得質子和中子有所謂的體積,也使得一般物體有體積。
物質常見的物質狀態有四種:固體、液體、氣體及等离子体。不過實驗技術的進步產生了許多新的物質狀態,像是玻色–爱因斯坦凝聚及费米子凝聚态。對於基本粒子的研究也產生了新的物質狀態,像是夸克-膠子漿[5]。在自然科學的歷史中,許多人都在研究物質的確切性質,物質是由許多離散組件組合而成的概念,即所謂的「物質粒子論」,最早是由古希臘哲學家留基伯及德谟克利特提出[6]。
愛因斯坦證明[7]所有物體都可以视为能量(即質能等價),之間的關係式即為著名的E=mc2displaystyle E=mc^2
,其中Edisplaystyle E
為能量,mdisplaystyle m
為質量,cdisplaystyle c
為光速,其數值為299792458 m/s。因此很小的質量可以轉換為很大的能量,例如正子和電子等費米子可以轉換為非物質的光子。不過雖然在這些過程中可以產生或是消滅物質,但是物質及能量的總和(透過E=mc2displaystyle E=mc^2
轉換)卻不會改變。
参考文献
^ R. Penrose. The mass of the classical vacuum. (编) S. Saunders, H.R. Brown. The Philosophy of Vacuum. Oxford University Press. 1991: 21. ISBN 0-19-824449-5.
^ Matter (physics). McGraw-Hill's Access Science: Encyclopedia of Science and Technology Online. [2009-05-24]. (原始内容存档于2011-06-17).
^ P. Davies. The New Physics: A Synthesis. Cambridge University Press. 1992: 1. ISBN 0-521-43831-4.
^ G. 't Hooft. In search of the ultimate building blocks. Cambridge University Press. 1997: 6. ISBN 0-521-57883-3.
^
RHIC Scientists Serve Up "Perfect" Liquid (新闻稿). Brookhaven National Laboratory. 18 April 2005 [2009-09-15].
^ J. Olmsted, G.M. Williams. Chemistry: The Molecular Science 2nd. Jones & Bartlett. 1996: 40. ISBN 0-8151-8450-6.
^ Einstein, A. Ist die Trägheit eines Körpers von seinem Energieinhalt abhängig?. Annalen der Physik. 1905, 18 (13): 639–643. Bibcode:1905AnP...323..639E. doi:10.1002/andp.19053231314.
外部链接
 | 查询維基詞典中的物质。 |
参见
物理学主题
哲学主题
- 反物質
- 暗物質
- 唯物論
- 能量
- 时间
- 哲学
- 物理学
- 相態
- 粒子物理学
自然的组成
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| 宇宙 | |
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| 地球 | - 地球科学
- 地球历史
- 地球的未來
- 地球構造
- 板块构造论
- 地球地质史
- 地质学
- 大洋
- 山
- 蓋亞假說
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| 天气 | |
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| 环境 | |
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| 生物 | - 生物圈
- 生命起源
- 生命演化史
真核生物
生物学
原核生物
- 病毒
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分類:自然
科學主題
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生物界物质层级
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| 个体层次 | 生物圈 > 生态系统 > 群落 > 种群 > 生物(个体)
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| 多细胞层次 | 器官系統 > 器官 > 組織
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| 细胞层次 | 細胞 > 細胞器
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| 分子层次 | 分子:生物大分子:蛋白质结构
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| 亚分子层次 | 原子 > 次原子粒子(复合粒子 > 基本粒子)
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