这些“奇怪的”外星星球可能是由外来物质构成的

2019年12月7日14:47:41 1 806 6978字阅读23分15秒

所有这些神秘的世界都围绕着超高密度中子星运行。


Three planets are known to orbit the pulsar PSR B1257+12,as depicted in this artist's illustration.In a new study,researchers suggest that a half-dozen other pulsar-circling planets might be made of exotic"strange matter."

已知有三颗行星围绕着脉冲星 PSR B1257+12运行,如图所示。在一项新的研究中,研究人员认为,其他六颗围绕着脉冲星旋转的行星可能是由奇异的"奇异物质"组成的

Astronomers have identified about a half dozen exoplanets that may be made of an exotic matter known as"strange matter"unknown on Earth.

天文学家已经发现了大约六颗系外行星,它们可能是由一种奇异的物质组成的,这种物质被称为地球上未知的"奇异物质"

The atoms that make up conventional matter have nuclei made of protons and neutrons,and protons and neutrons are composed of subatomic particles called quarks.There are six kinds of quarks:up,down,strange,charm,bottom and top.Up and down quarks are the lightest.Each proton contains two up quarks and one down quark,whereas each neutron has two down quarks and one up quark.

构成普通物质的原子有由质子和中子构成的原子核,而质子和中子则由称为夸克的亚原子粒子构成。夸克有六种:上夸克、下夸克、奇异夸克、魅夸克、底夸克和顶夸克。上下夸克是最轻的。每个质子包含两个上夸克和一个下夸克,而每个中子包含两个下夸克和一个上夸克。

Scientists have created strange quarks through powerful collisions in particle accelerators,but these quarks quickly decayed into more stable particles.However,previous research suggested that strange quarks might prove stable within the superdense stellar corpses known as neutron stars.

科学家通过粒子加速器中的强大碰撞创造出了奇异夸克,但这些夸克很快就衰变为更稳定的粒子。然而,之前的研究表明,奇异夸克可能在被称为中子星的超密恒星尸体中被证明是稳定的。

Neutron stars are the remains of large stars that died in cataclysmic explosions known as supernovas,each cramming a mass about 1.3 to 2.5 times that of the sun into a city-size sphere about 12 miles(20 kilometers)across.Their name derives from their exotic composition:The powerful gravitational pull of these remnants crushes protons and electrons together to form neutrons.

中子星是大型恒星的残骸,它们死于称为超新星的灾难性爆炸,每颗中子星都将相当于太阳1.32.5倍的质量填充到一个直径约为12英里(20公里)的城市大小的球体中。它们的名字来源于它们奇特的组成:这些残余物强大的引力将质子和电子压在一起形成中子。

In theory,at the extreme pressures found in the cores of especially heavy neutron stars,neutrons might break down into a soup of their component quarks.Prior work suggested that,given enough pressure,half of the neutrons'down quarks might transform into strange quarks,leading to strange quark stars made of strange matter.

理论上,在特别重的中子星的内核中发现的极端压力下,中子可能会分解成由它们的组分夸克组成的混合物。之前的工作表明,在足够的压力下,中子的下夸克的一半可能会转变成奇异夸克,从而形成由奇异物质构成的奇异夸克恒星。

In principle,strange matter should be heavier and more stable than normal matter.Moreover,it might even be capable of converting ordinary matter it encounters into more strange matter.Previous research suggested that a strange quark star that occasionally spurts out strange matter could quickly convert a neutron star orbiting it in a binary system into a strange quark star in just 1 millisecond to 1 second.

原则上,奇异物质应该比正常物质更重、更稳定。此外,它甚至可以将遇到的普通物质转化为更奇怪的物质。先前的研究表明,一颗偶尔喷射出奇怪物质的奇异夸克星可以在1毫秒到1秒的时间内将一颗双星系统中环绕它运行的中子星迅速转变为奇异的夸克星。

Prior work also suggested that neutron stars and strange quark stars should have very similar average densities,said Jin-Jun Geng,an astrophysicist at Nanjing University in China and co-author of the new research that identified exoplanets possibly made of strange matter.This would make it difficult to distinguish them from one another and thus to see if strange quark stars are real.

中国南京大学的天体物理学家耿(音译)说,之前的研究也表明,中子星和奇异夸克星的平均密度应该非常相似。耿是这项新研究的合著者,该研究确定了可能由奇异物质构成的系外行星。这样就很难将它们彼此区分开来,也就很难看出奇怪的夸克星是否存在。

However,previous research also indicated that planets made of strange matter could exist and that scientists might distinguish these planets from planets made of conventional matter via their densities.Normal planets have densities that are no more than 1,870 lbs.per cubic foot(30 grams per cubic centimeter).In contrast,strange planets would typically have densities of nearly 25 million billion lbs.per cubic foot(400 trillion grams per cubic centimeter),Geng and his colleagues said.(For comparison,gold has a density of about 1,200 lbs.per cubic foot,or nearly 19.3 grams per cubic centimeter.)

然而,之前的研究也表明,由奇异物质构成的行星可能存在,科学家可以通过其密度将这些行星与由常规物质构成的行星区分开来。正常行星的密度不超过1870磅。每立方英尺(每立方厘米30)。相比之下,奇异行星的密度通常接近2500亿磅。耿和他的同事说,每立方英尺(每立方厘米400万亿克)(相比之下,黄金的密度约为1200磅。每立方英尺,或接近每立方厘米19.3)

"While a strange quark star is very similar to a neutron star,the difference between a strange planet and a normal planet is huge,"Geng told Space.com.

耿爽告诉《太空网》说:"虽然一颗奇异夸克星和一颗中子星非常相似,但是一颗奇异行星和一颗普通的行星之间的差别是巨大的。"

The extraordinary density of strange planets means they can survive even if they come within 14.7 miles(23.7 km)of a strange quark star they are orbiting,virtually grazing its surface.In contrast,a normal planet's orbit can take it only as close as about 348,000 miles(560,000 km)before getting ripped apart by the dead star's gravitational pull,the researchers said.

奇异行星的密度之大,意味着即使它们靠近一颗奇异夸克恒星14.7英里(23.7公里)之内,它们仍然能够存活下来,事实上,它们正掠过这颗夸克恒星的表面。研究人员说,相比之下,正常行星的轨道距离恒星只有348,000英里(560,000公里),然后才会被死亡恒星的引力撕裂。

Now,based on this feature of these strange worlds,scientists in China say they may have detected four good candidates for strange planets.These exoplanets revolve around pulsars—rapidly spinning neutron stars that appear to flash like lighthouse beacons from our perspective here on Earth—in orbits of about 348,000 miles(560,000 km)or less.The researchers also discovered two other planets that took only slightly longer to complete an orbit and therefore also might also be candidates for strange planets.

现在,基于这些奇怪世界的这一特征,中国的科学家说,他们可能已经发现了四个奇异行星的候选者。这些系外行星围绕着脉冲星旋转。脉冲星是一种快速旋转的中子星,从我们地球的角度来看,它像灯塔一样闪烁,轨道长约34.8万英里(56万公里)或更短。研究人员还发现了另外两颗行星,它们完成一个轨道的时间稍微长一些,因此也可能是奇异行星的候选者。

The researchers noted that strange planets might also orbit what appear to be white dwarfs—the remnants of normal stars that have burned all the hydrogen fuel in their cores—but are actually strange quark dwarfs.They found five exoplanets around white dwarfs orbiting suspiciously close to these stellar remnants,suggesting that they might also be strange planets.

研究人员指出,奇异行星可能也围绕着看起来像是白矮星的轨道运行,白矮星是普通恒星的残骸,它们燃烧了核心中所有的氢燃料,但实际上是奇异夸克矮星。他们在白矮星周围发现了五颗系外行星,它们的轨道可疑地靠近这些恒星残骸,这表明它们也可能是奇异行星。

However,the scientists cautioned that these potential strange planets might actually be white dwarfs,"which are also relatively compact objects that could be close-in to their host pulsars,"Geng said.

然而,科学家们警告说,这些潜在的奇异行星实际上可能是白矮星,"它们也是相对致密的物体,可能靠近它们的主脉冲星,"耿说。

But"the masses of our candidates are generally less than 10 Jupiter masses,"Geng said.In contrast,white dwarfs generally range from about 150 to 1,200 times the mass of Jupiter.

但是"我们的候选人的质量一般不到木星质量的10倍,"耿说。相比之下,白矮星的质量一般在木星的1501200倍之间。

One way to potentially determine if these exoplanets are made of strange matter is to look for gravitational waves from them.Gravitational waves are ripples in the fabric of space and time that are generated from any object with mass in motion.Really strong gravitational waves are emitted by really big masses,such as pairs of neutron stars crashing into each other.

确定这些系外行星是否由奇异物质构成的一个潜在方法是从它们身上寻找引力波。引力波是时空结构中的涟漪,它是由任何运动中的物体产生的。真正强大的引力波是由真正的大质量发射出来的,比如成对的中子星相互撞击。

A strange planet orbiting or merging with a strange quark star should give off gravitational waves that are distinct from those emitted by pairs of neutron stars and normal planets because of the dense nature of strange planets,the researchers said.They suggested that the ongoing Advanced LIGO(Laser Interferometer Gravitational-Wave Observatory)project and the proposed Einstein Telescope may be able to detect the bursts of gravitational waves from the mergers of strange planets and strange quark stars.

研究人员说,由于奇异行星的致密性,一颗围绕着奇异夸克星运行或者与之合并的奇异行星应该会释放出与成对的中子星和普通行星不同的引力波。他们认为,正在进行的高级 LIGO(激光干涉引力波天文台)项目和拟议中的爱因斯坦望远镜可能能够探测到来自奇异行星和奇异夸克星合并的引力波爆发。

"We believe that we have proposed a completely new method that could efficiently identify strange quark matter objects,"Geng said.

"我们相信,我们已经提出了一种全新的方法,可以有效地识别奇怪的夸克物质对象,"耿说。

来源:https://www.space.com/alien-planets-pulsars-strange-matter.html

  • 本文由 发表于 2019年12月7日14:47:41
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    • avatar zbt 4

      “一颗偶尔喷射出奇怪物质的奇异夸克星可以在1毫秒到1秒的时间内将一颗双星系统中环绕它运行的中子星迅速转变为奇异的夸克星”
      这威力太大了,按科博拉的说法,地球被负面势力用夸克炸弹威胁,这如果炸了,那就是同归于尽,而且死得痛快……