cover of episode What a dark energy discovery means for the fate of the universe

What a dark energy discovery means for the fate of the universe

2025/3/20
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Ian Sample
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Madeleine Finlay
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Saul Perlmutter
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@Ian Sample : 最新研究表明暗能量的影响力正在减弱,这可能挑战我们对宇宙运行方式和最终命运的基本理解。这一发现来自DESI望远镜的观测数据,该数据结合了超新星和其他来源的测量结果。暗能量似乎正在减弱,宇宙膨胀仍在加速,但速度比以前慢了。这表明暗能量的性质可能并非我们之前认为的宇宙常数,而是一个随时间衰减的场。 关于暗能量的本质,我们仍然知之甚少,但这一发现为我们提供了关于暗能量性质的第一个线索,它可能是一个随时间衰减的场。宇宙的未来取决于引力(物质)和暗能量之间的平衡。如果暗能量继续减弱,宇宙最终的命运可能与之前的预测不同,甚至可能最终停止膨胀并坍缩。 @Saul Perlmutter : 我们最初的研究旨在利用超新星作为宇宙中的距离标记,来测量宇宙膨胀由于引力而减速的程度。Ia型超新星都发出相同数量的光,因此其亮度可以作为测量距离的指标。通过观测超新星的红移,我们可以了解它们远离我们的速度,从而研究宇宙的膨胀。 最初的研究结果令人惊讶,我们发现宇宙不仅在膨胀,而且膨胀速度还在加快,这与科学家的预期相反。宇宙加速膨胀的原因是一种神秘的力量——暗能量,它可能存在于空间的真空中,并构成宇宙约70%。暗能量可能并非宇宙常数,而是一个新的场,如果最新数据属实,那么暗能量可能不是爱因斯坦所说的宇宙常数,而是一个新的场。这将意味着宇宙的最终命运可能与之前的预测不同,甚至可能最终停止膨胀并坍缩。 @Madeleine Finlay : 本期节目讨论了最新关于暗能量的研究发现。研究人员利用DESI望远镜,创建了宇宙的三维地图,以揭示宇宙膨胀和暗能量运作的更多细节。研究发现宇宙不仅在膨胀,而且膨胀速度还在加快,这与科学家的预期相反。 这一发现为我们理解宇宙的运行和最终命运提供了新的视角。

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This chapter explores the concept of dark energy, starting from the initial understanding of the universe's expansion and the surprising discovery of its accelerating rate. It delves into the use of supernovae as distance markers and explains how this led to the identification of dark energy as a mysterious force counteracting gravity.
  • The universe's expansion was initially believed to decelerate due to gravity.
  • Supernovae observations revealed the universe's accelerating expansion.
  • Dark energy is a mysterious force counteracting gravity, making up about 70% of the universe.

Shownotes Transcript

Dark energy, the mysterious force powering the expansion of the universe, appears to be weakening over time, according to a major cosmological survey that has thrown the laws of modern physics into doubt. Ian Sample tells Madeleine Finlay how this new finding could shed light on the ultimate fate of the cosmos, and Saul Perlmutter, who won a Nobel prize for his work proving the universe is expanding, describes how the new development could upend assumptions about how this mysterious force operates. Help support our independent journalism at theguardian.com/sciencepod