Merger of two mashimo meusi has three stages: inspiral, merger and ringdown phases. Characteristic mawimbi ya mvuto are emitted in each phase. The last ringdown phase is very brief and encode information about properties of final nyeusi shimo. Reanalysis of data from binary nyeusi shimo merger event GW190521 has provided, for the first time, evidence of signature aftershocks of the merger in the form of two separate faint ringdown frequencies produced by the resulting single nyeusi shimo as it settled down to a stable symmetrical form. This is the first detection of multiple gravitational-wave frequencies in the ringdown stage. Just like a bell ‘rings’ for some time after being stuck, the resulting single distorted nyeusi shimo formed after the merger ‘rings’ for some time emitting faint mawimbi ya mvuto before achieving symmetrical stable form. And, just the way shape of the bell determines the specific frequencies with which the bell rings, similarly, as per no-hair theorem, mass and spin of the nyeusi shimo determine ringdown frequencies. Hence, this development paves the way for use of ringdown frequencies to study properties of final nyeusi shimo.
Mashimo meusi are massive objects with extremely strong gravitational fields. When two kuzunguka mashimo meusi spiral around each other and eventually coalesce, the fabric of nafasi-times around them are disturbed that creates ripples of mawimbi ya mvuto radiating outwards. Since September 2015 when gravitational-wave astronomy began with LIGO’s first detection of mawimbi ya mvuto generated by merger of two mashimo meusi 1.3 billion light years away, merging mashimo meusi are now routinely detected almost once every week.
Kuunganishwa kwa mashimo meusi has three phases. When the two mashimo meusi are widely separated, they slowly obiti each other emitting weak gravitational waves. The binary gradually moves to smaller and smaller njia as the energy of the system is lost in the form of mawimbi ya mvuto. Hii ni awamu ya msukumo ya mshikamano. Inayofuata ni awamu ya kuunganisha wakati wawili hao mashimo meusi get close enough to coalesce to form a single nyeusi shimo with distorted shape. Strongest gravitational waves (GWs) are emitted at this stage which are now routinely detected and recorded by gravitational-wave observatories.
Awamu ya kuunganisha inafuatwa na hatua fupi sana inayoitwa hatua ya kushuka wherein the resulting single distorted nyeusi shimo quickly achieves more stable spherical or spheroidal form. Mawimbi ya mvuto emitted in the ringdown phase are damped and much fainter than the GWs released in the merger phase. Just as a bell ‘rings’ for some time after being stuck, the resulting single nyeusi shimo ‘rings’ for some time emitting much fainter mawimbi ya mvuto before achieving symmetrical stable form.
The faint multiple ringdown frequencies of mawimbi ya mvuto released during the ringdown phase of merger of two mashimo meusi were undetected so far.
A research team has recently been successful in detecting multiple gravitational-wave frequencies in the ringdown stage of binary nyeusi shimo merger event GW190521. They searched for individual fading tones in the ringdown frequencies without considering any relation with frequencies and damping times and were successful in identifying two modes implying the resulting deformed nyeusi shimo emitted at least two frequencies after the merger. This was predicted by Einstein’s general relativity hence the result confirms the theory. Further, researchers compared the frequencies and damping times of the two ringdown modes found in the merger event to test the “no-hair theorem” (that mashimo meusi are completely characterised by mass and spin and no other “hair” is needed to describe its features) and found nothing beyond general relativity.
Hili ni tukio muhimu kwa sababu ilifikiriwa sana kuwa uchunguzi wa masafa mengi ya mteremko haungewezekana kabla ya vigunduzi vya mawimbi ya uvutano ya kizazi kijacho kupatikana katika siku zijazo.
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Vyanzo:
- Kapano, CD et al. 2023. Multimode Quasinormal Spectrum kutoka kwa Shimo Jeusi Lililotikiswa. Barua za Mapitio ya Kimwili. Vol. 131, Toleo la 22. 1 Desemba 2023. DOI: https://doi.org/10.1103/PhysRevLett.131.221402
- Max-Planck-Institut fürGravitationsphysik(Albert-Einstein-Institut), 2023. Habari - Ambao shimo jeusi linasikika. Inapatikana kwa https://www.aei.mpg.de/749477/for-whom-the-black-hole-rings?c=26160
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