[Inspiration strikes in odd ways and at strange times. Don't ask me why I wrote this, because I've no idea. In any case I hope some of you enjoy it; and the science behind it is described here.]
Quantum Theory claims: “All tales are told!”
But gravity demurs; for Einstein’s bold
Equations show that black holes tell no tales
And keep their secrets hidden deep within.
So it remained til nineteen seventy-four
When Hawking’s striking calculation showed
That black holes aren’t exactly black: they glow!
They shrink, wither, and in a flash they die
And take their hidden secrets to their graves,
Killing Quantum Theory as they go.
And if you disagreed, and did believe
that black holes’ tales are written in their glow,
No matter; this kills Quantum Theory too,
For once inside, a story can’t come out,
And copying puts a quantum world in doubt.
Thus Hawking argued that he’d made it clear
That Quantum Theory had to be revised.
“But not so fast” cried Susskind and ‘t Hooft,
For Quantum Theory’s cleverer than you think;
T’was twenty years ago the claim was made
That black holes may be complementary:
While those who venture in do find the tales
Are written clearly in the black hole’s deep,
Those outside have a very different view.
They think the stories rest upon the edge
And later end up written in the sky.
So strange this sounds! And yet, it has been shown
That in a quantum world of certain type
The information stored within a space
Can also seem to be upon its face!
Consensus grew that Quantum Theory’s safe
And even Hawking painfully agreed
The argument was strong; nine years ago
He publicly announced his change of heart.
But still it wasn’t yet precisely clear
Just how it is that black holes disappear
Without undoing Quantum Theory’s base;
And then the AMPS collaboration found,
While trying to ensure the case was sound,
The complementary black hole in fact
Could not exist! At least not as we thought,
For when the tale’s half written in the sky
The black hole’s inside could no longer be,
And anyone who reached the edge would die.
“Firewall”, the cry rose from the crowd;
And troubling it was; such walls would flout
The principles that Einstein had set out
To underpin his theory of space and time
And gravity — the very one we used
To show black holes exist, and find them too.
So something’s wrong! But what? What must we change?
Which principle is it that we must revise?
Which equation fails, and in what guise?
Confusion spreads across the blackened skies…
Proposals have been made, but none is firm.
Among them Hawking’s recent; he suggests
A black hole’s even less black than he thought:
Not only does it faintly glow, it leaks
Like politicians, whispering its tales
In code; and thus whatever is inside
Gets out! Though in a highly scrambled form.
(So do not try to enter and return!)
These holes aren’t complementary; instead
Their inner stories are somehow released
Before the holes that store them are deceased.
But be not sure; for Hawking’s story’s vague
And many others have suggested ways
That current controversy may be stemmed.
Yet none of them seem likely soon to lift
The murky darkness that still makes us blind
And hides the truth from all of humankind.
© Matt Strassler February 5, 2014