ଉଇକିପିଡ଼ିଆ ରୁ
ସିଧାସଳଖ ଯିବେ ଦିଗବାରେଣିକୁ, ଖୋଜିବେ
Schwarzschild black hole
Simulation of gravitational lensing by a black hole, which distorts the image of a galaxy in the background

କୃଷ୍ଣଗର୍ତ୍ତ (ଇଂରାଜୀ: Black hole; ବ୍ଲାକ୍ ହୋଲ୍) ମହାଶୂନ୍ୟ-କାଳରେ (spacetime) ଏପରି ଏକ ସ୍ଥାନ ଯାହାର ମାଧ୍ୟାକର୍ଷଣ ସବୁକିଛି ଏପରିକି ଆଲୋକକୁ ବି ଖସି ଯିବାକୁ ଦେଇନଥାଏ ।[୧]


Simulated view of a black hole in front of the Large Magellanic Cloud. Note the gravitational lensing effect, which produces two enlarged but highly distorted views of the Cloud. Across the top, the Milky Way disk appears distorted into an arc.

ଜନ୍ ମାଇକେଲ୍ ୧୭୮୩ ମସିହାରେ ରୟାଲ ସୋସାଇଟିର ହେନେରୀ କଭେଣ୍ଡିସ୍‌ଙ୍କ ପାଖକୁ ଏକ ଚିଠି ଲେଖିଥିଲେ; ସେଥିରେ ସେ ପ୍ରଥମେଥର ପାଇଁ ଏକ ବିଶାଳ ବସ୍ତୁ (body) କଥା କହିଥିଲେ ଯେଉଁଥିରୁ କୌଣସି ଜିନିଷ ଏପରିକି ଆଲୋକ ବି ଖସିଯାଇପାରେ ନାହିଁ ।

If the semi-diameter of a sphere of the same density as the Sun were to exceed that of the Sun in the proportion of 500 to 1, a body falling from an infinite height towards it would have acquired at its surface greater velocity than that of light, and consequently supposing light to be attracted by the same force in proportion to its vis inertiae, with other bodies, all light emitted from such a body would be made to return towards it by its own proper gravity.
—ଜନ୍ ମାଇକେଲ୍[୨]

୧୭୯୬ ରେ, ଗଣିତଜ୍ଞ ପିଅର୍-ସାଇମନ୍ ଲାପ୍ଲାସ୍ ନିଜ ବହି Exposition du système du Monde ର ପ୍ରଥମ ଓ ଦ୍ଵିତୀୟ ସଂସ୍କରଣରେ ଏହି ଆଇଡିଆର ପ୍ରଚାର କରିଥିଲେ । (ଏହାକୁ ପରବର୍ତ୍ତୀ ସଂସ୍କରଣ ଗୁଡ଼ିକରେ ବାଦ୍ ଦିଆଯାଇଥିଲା ।).[୩][୪] Such "dark stars" were largely ignored in the nineteenth century, since it was not understood how a massless wave such as light could be influenced by gravity.[୫]

ଗୁଣ ଓ ସଂରଚନା[ସମ୍ପାଦନା]

ଭୌତିକ ଗୁଣ[ସମ୍ପାଦନା]

ଗଠନ ଓ ବିବର୍ତ୍ତନ[ସମ୍ପାଦନା]



  1. Wald 1984, pp. 299–300
  2. Michell, J. (1784). "On the Means of Discovering the Distance, Magnitude, &c. of the Fixed Stars, in Consequence of the Diminution of the Velocity of Their Light, in Case Such a Diminution Should be Found to Take Place in any of Them, and Such Other Data Should be Procured from Observations, as Would be Farther Necessary for That Purpose". Philosophical Transactions of the Royal Society 74 (0): 35–57. Bibcode:1784RSPT...74...35M. JSTOR 106576. doi:10.1098/rstl.1784.0008. 
  3. Gillispie, C. C. (୨୦୦୦). Pierre-Simon Laplace, ୧୭୪୯–୧୮୨୭: a life in exact science. Princeton paperbacks. Princeton University Press. p. ୧୭୫. ISBN ୦-୬୯୧-୦୫୦୨୭-୯. 
  4. Israel, W. (୧୯୮୯). "Dark stars: the evolution of an idea". In Hawking, S. W.; Israel, W. ୩୦୦ Years of Gravitation. Cambridge University Press. ISBN ୯୭୮-୦-୫୨୧-୩୭୯୭୬-୨. 
  5. Thorne 1994, pp. 123–124

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