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Big Bang singularity

Does a singularity contain mass?? if yes then according to big bang , our universe sprang into existence as “singularity” around 13.7 billion years ago. it means there was already a mass centered in zero volume.

and only a black-hole has singularity it means at the time of big bang there was a black hole in which explosion occurred.
please guide me and give me ans.

 

Asked Shyam

 

Answer:

The word singularity means

“the state, fact, quality, or condition of being singular.”

“a point at which a function takes an infinite value, especially in space–time when matter is infinitely dense, such as at the centre of a black hole.”

” a point at which the derivative of a given function of a complex variable does not exist but every neighborhood of which contains points for which the derivative does exist”

Evidently, singularity refers to a unique situation, in big bang whatever state of affairs triggered contributes to the singularity.

 

Refer to

https://en.wikipedia.org/wiki/Initial_singularity

http://www.hawking.org.uk/the-beginning-of-time.html

Did The Universe Really Begin With a Singularity?

http://www.big-bang-theory.com/

Time Stops ?!!

Davide Asks again:

“i have one question about time. Once professor Stephen Hawking said that if hypothetically a man stand in font of a black hole the time will stop for him.Now we all know how time works because we understated time we have study it but dose our body understand it?what i mean is if time will stop for me will my body stop as well is natural course?(getting hold,cellular production etc)i don’t think so right?so what the connection between time and body if exist one?and why scientist always speak about time stopping  only and not    include in the argument human body as well?after all according to Einstein the past,present,future are already there,we only walk through it and since we are  interacting with it as  a living been   time, space and us  are lock together .So standing in front of a black hole, if time stops without effecting my body ,time stop in relation to what?  Thank you kindly for your TIME:)”

(The post is not corrected for grammar and spelling)

Response from visitors invited

Black Holes and Thermal Radiation

Varun G asked

“Do black holes produce thermal radiation, as expected on theoretical grounds and do they absorb light?”

Ans: Hope you are talking about the Hawking radiation.

Any body at a temperature above absolute zero emits radiations. If the temperature of black body is not absolute zero (It was Stephen Hawking who predicted that black holes should have a finite, non-zero temperature, and hence the name “Hawking Radiation”) it will emit radiation.

In a black hole emitting radiation, there is a loss of mass. If the mass decreased due to Hawking Radiation is more than the mass gained by the black holes via alternate means, the net mass of the black holes will go on decreasing. (This is called “black hole evaporation” Further, it has been noted that the black holes with lower mass emit more radiations than the heavier ones.

This answer may seem contradicting the definition of black hole itself.

“A black hole is a body whose gravitational force of attraction is so huge that even electromagnetic radiation cannot escape from it” as the definition goes.

But the Hawking Radiation is caused by Quantum effects. The processes behind the “escape” of radiation from a black hole is thought to be

  • Vacuum Fluctuations and
  • Quantum tunneling

The above terms and concept will be too high to be discussed at school level. However for the curious ones, I am giving some links to explore.

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