Hawking Radiation

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I recently read something that made me understand the answer to OP's question as this:

The words "the antiparticle" can be read in one of two ways. Some particles are Mater and some particles are antimater. In the first context saying "the electron is the mater particle and the positron is the antiparticle" means that the positron is Antimater and therefore is the antiparticle. In the second context "a positron is the antiparticle to an electron, and an electron it the antiparticle to a positron". In this context "the antiparticle" doesn't mean that the electron is antimater or that the positron is antimater (as we know, it is the positron that is antimater) but that they are opposite of one another.

The description of Hawking's evaporating black holes talking about a particle and an antiparticle bubbling up out of the quantum foam and then before they can annihilate each other one of them gets sucked in to the black hole and is lost behind the event horizon. The statement "the antiparticle is absorbed into the black hole" is using the word "antiparticle" in the second sense and not in the first. It means "one of the two opposite particles" not "the one that is antimater".

I also read that the analogy itself is only an analogy and an oversimplification of very complex math and not completely accurate. But I don't think that this is relevant to OP's original question.

I am reading a book now called “The Perfect Theory” by Pedro G. Ferreira. I don't recall when exactly my understanding changed - while reading this book or reading something else on the internet with this book as context in my mind. The book mentions Hawking's evaporating black holes but not in great technical detail - it does give a large amount historical detail and this help (for me) to put certain things in perspective by providing a narrative line of the order in which certain things were understood and what the thinking was before and after.

https://www.skyatnightmagazine.com/spac ... radiation/

BBC Sky At Night Magazine is published by Our Media Ltd (an Immediate Group Company) under licence from BBC Studios, which helps fund new BBC programmes.

What is Hawking radiation?

By Colin Stuart

Published: September 9, 2021 at 12:47 pm

One of Professor Stephen Hawking's most famous ideas is known as Hawking radiation. By leaking particles back into space, a black hole can very slowly evaporate away.

But what exactly is Hawking radiation, and how is it generated?

Physicists know that on the smallest scales of the Universe pairs of particles pop into existence, suddenly appearing out of the vacuum only to rapidly recombine and disappear again.

They are called 'virtual particles' and Stephen Hawking wondered what would happen if this process unfolded right on the event horizon of a black hole.

If one particle crosses the event horizon then it is forever separated from its companion and can never recombine with it.

The particles that are left outside the event horizon are called 'Hawking radiation'.

However, the particles had to 'borrow' energy from empty space to appear in the first place.

Normally this debt is repaid when they recombine, but as that can't happen in this case they effectively default on the loan.

The repayment has to come from somewhere: the black hole.

So over time a black hole slowly loses mass due to the constant need to cover these energy debts to empty space. It means that a black hole slowly evaporates over time.

Although 'slowly' is a bit of an understatement. The number of years it would take a black hole with the same mass as the Sun to evaporate is one followed by 64 zeros - many times the current age of the Universe.

Author
Astronomy author and writer Colin Stuart

Science communicator

Colin Stuart is an astronomy author and speaker.

Black holes Cosmology

BBC Sky At Night Magazine is published by Our Media Ltd (an Immediate Group Company) under licence from BBC Studios, which helps fund new BBC programmes.
(C) Immediate Media Company Ltd. 2022

Sorry, I completely forgot all about this thread.

Thank you magz - your explanation helped me a lot understanding this.

I'm reading Something Deeply Hidden by Sean Carroll, it provides a very intuitive way of thinking about Quantum Mechanics, and explaining the Uncertainty Principle and other phenomena.