Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

All-You-Can-Eat at the End of the Universe

12.08.2014

A new model shows how early black holes could have grown to over a billion solar masses

At the ends of the Universe there are black holes with masses equaling billions of our sun. These giant bodies – quasars – feed on interstellar gas, swallowing large quantities of it non-stop.


A small black hole gains mass: Dense cold gas (green) flows toward the center of a stellar cluster (red cross in blue circle) with stars (yellow); the erratic path of the black hole through the gas (black line) is randomized by the surrounding stars

Thus they reveal their existence: The light that is emitted by the gas as it is sucked in and crushed by the black hole's gravity travels for eons across the Universe until it reaches our telescopes.

Looking at the edges of the Universe is therefore looking into the past. These far-off, ancient quasars appear to us in their “baby photos” taken less than a billion years after the Big Bang: monstrous infants in a young Universe.

Normally, a black hole forms when a massive star, weighing tens of solar masses, explodes after its nuclear fuel is spent. Without the nuclear furnace at its core pushing against gravity, the star collapses: Much of the material is flung outwards in a great supernova blast, while the rest falls inward, forming a black hole of only about 10 solar masses.

Since these ancient quasars were first discovered, scientists have wondered what process could lead a small black hole to gorge and fatten to such an extent, so soon after the Big Bang.

In fact, several processes tend to limit how fast a black hole can grow. For example, the gas normally does not fall directly into the black hole, but gets sidetracked into a slowly spiraling flow, trickling in drop by drop. When the gas is finally swallowed by the black hole, the light it emits pushes out against the gas. That light counterbalances gravity, and it slows the flow that feeds the black hole.

So how, indeed, did these ancient quasars grow? Prof. Tal Alexander, Head of the Particle Physics and Astrophysics Department, proposes a solution in a paper written together with Prof. Priyamvada Natarajan of Yale University, which recently appeared in Science.

Their model begins with the formation of a small black hole in the very early Universe. At that time, cosmologists believe, gas streams were cold, dense, and contained much larger amounts of material than the thin gas streams we see in today’s cosmos. The hungry, newborn black hole moved around, changing direction all the time as it was knocked about by other baby stars in its vicinity.

By quickly zigzagging, the black hole continually swept up more and more of the gas into its orbit, pulling the gas directly into it so fast, the gas could not settle into a slow, spiraling motion. The bigger the black hole got, the faster it ate; this growth rate, explains Alexander, rises faster than exponentially.

After around 10 million years – a blink of an eye in cosmic time – the black hole would have filled out to around 10,000 solar masses. From then, the colossal growth rate would have slowed to a somewhat more leisurely pace, but the black hole’s future path would already be set – leading it to eventually weigh in at a billion solar masses or more.

 

Prof. Tal Alexander’s research is supported by the European Research Council.

Yivsam Azgad | Eurek Alert!
Further information:
http://wis-wander.weizmann.ac.il/all-you-can-eat-at-the-end-of-the-universe?press-room-rb#.U-pXYGEcTct

Further reports about: All-You-Can-Eat Big Bang Physics Universe Weizmann black hole gravity quasars solar masses

More articles from Physics and Astronomy:

nachricht Heating quantum matter: A novel view on topology
22.08.2017 | Université libre de Bruxelles

nachricht Engineering team images tiny quasicrystals as they form
18.08.2017 | Cornell University

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Fizzy soda water could be key to clean manufacture of flat wonder material: Graphene

Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.

As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...

Im Focus: Exotic quantum states made from light: Physicists create optical “wells” for a super-photon

Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.

Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...

Im Focus: Circular RNA linked to brain function

For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.

While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...

Im Focus: RAVAN CubeSat measures Earth's outgoing energy

An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.

The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...

Im Focus: Scientists shine new light on the “other high temperature superconductor”

A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.

Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Papers – ICNFT 2018, 5th International Conference on New Forming Technology

16.08.2017 | Event News

Sustainability is the business model of tomorrow

04.08.2017 | Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

 
Latest News

Cholesterol-lowering drugs may fight infectious disease

22.08.2017 | Health and Medicine

Meter-sized single-crystal graphene growth becomes possible

22.08.2017 | Materials Sciences

Repairing damaged hearts with self-healing heart cells

22.08.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>