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Comment by adastra22 | Hacker News Reader

> We know that gravity alone can create radiation - the Hawking one

To be pedantic, we don't know this. Hawking radiation has never been observed.

Not only has Hawking radiation not been observed but the article starts with a "may have" and concludes by pointing out that there aren't conditions to observe the phenomenon described today.

Maybe I'm just not a fan of strong language, making it appear we know something, where we don't.

to be even more pedantic, hawking radiation isn't exactly created by gravity

furthermore, so far in universe (after big bang), nothing is really created, only transformed.

and (depending how time actually works) transformed also may be wrong, rather, everything simply is and time is our hallucination of reality

This does not compute in my mind, energy transfer (in some form) it is observed phenomena (my understanding (primitive) of time is energy transfer), even on quantum level we can measure it, what am I missing ?

You aren’t missing anything. He’s playing definitional word games, a common pastime of philosophers.

Dark energy is adding energy to the universe (mechanism unknown).

How does expansion of universe increases total energy ?

If anything seems like due to dark energy total energy dissipation per area is increasing until death of universe.

It takes work to separate two masses from each other (increasing gravitational potential energy). The universe is not just expanding, which might possibly be understood in an energy conserving way if the rate of expansion is slowing, but it is expanding at an ever increasing rate. Ergo enter guy is being dumped into the universe from some repository/field/whatever that we don’t understand. That’s what Dark Energy is.

In theory it’s created by the singularity boundary.

Related, I posted a paper on William Sidis earlier today where he explored the idea of a black hole before they were theorized or discovered: https://www.sidis.net/animate.pdf

Relevant: https://phys.org/news/2021-02-stationary-hawking-analog-blac...

Not particularly. This isn’t an actual observation, this is just an experiment that attempts to create some analogous phenomena.

didn't the LHC create a black hole that immediately evaporated due to Hawking radiation? ..maybe it was only a theory that the LHC could do that but i thought it actually did create one.

No. That's far beyond our capabilities. Somebody calculated that LHC would have to be over 1000 light years in diameter to do this (and then still we would have to wait for thousands of years for particles to get accelerated).

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