Recent polls have found that 42 percent of Americans and 52 percent of people in the UK believe in ghosts - a huge percentage when you consider that no one has ever come up with irrefutable proof that they even exist.
But we might have had proof that they don't exist all along, because as British theoretical physicist Brian Cox recently pointed out, there's no room in the Standard Model of Physics for a substance or medium that can carry on our information after death, and yet go undetected in the Large Hadron Collider.
"If we want some sort of pattern that carries information about our living cells to persist, then we must specify precisely what medium carries that pattern, and how it interacts with the matter particles out of which our bodies are made," Cox, from the University of Manchester, explained in an episode of BBC's The Infinite Monkey Cage.
"We must, in other words, invent an extension to the Standard Model of Particle Physics that has escaped detection at the Large Hadron Collider. That's almost inconceivable at the energy scales typical of the particle interactions in our bodies."
Astrophysicist Neil deGrasse Tyson, who was also on the show, replied, "If I understand what you just declared, you just asserted that CERN, the European Centre for Nuclear Research, disproved the existence of ghosts."
"Yes," said Cox.
It's become glaringly obvious that the Standard Model of Physics is an incomplete theory, with several gaping holes that physicists have been trying to patch up for decades, but Cox says the existence of ghosts doesn't fall within the 'known unknowns' of the Standard Model.
The second law of thermodynamics states that the total entropy of an isolated system always increases over time.
Entropy is a measure of the randomness or disorder within a closed or isolated system, and the second law of thermodynamics states that as usable energy is lost, chaos increases - and without extra energy being put into a system, that progression towards disorder can never be reversed.
In other words, energy is always lost to heat in any system - whether it's a washing machine or the Universe - and you can never get back all the energy you put in.
The principle can be used to explain why the arrow of time only ever marches forwards; why there's a past, future, and present; and why you can't un-scramble an egg, because it would lower the Universe's entropy.
So how does that apply to ghosts?
Because we can't touch and interact with them, ghosts can't be made of matter, but instead of energy.
And if energy is necessarily lost within every system - particularly if they're doing anything that requires using more of it, such as moving, emitting light, or making spooky sounds - it would be impossible for them to maintain their existence for any significant period of time.
The second nail in the coffin comes from the Large Hadron Collider, because while there are things about the Universe we still can't find using this giant particle accelerator, what we can see very well is the way energy drives our cells' information.
If we assume that the energy that sustains ghosts isn't an entirely new substance or medium, but carries on from when we were living, then this mysterious force controlling the particles that make up our cells would have been detected in the Large Hadron Collider by now.
"I would say if there's some kind of substance that's driving our bodies, making my arms move and legs move, then it must interact with the particles out of which our bodies are made," says Cox.
"And seeing as we've made high precision measurements of the ways that particles interact, then my assertion is that there can be no such thing as an energy source that's driving our bodies."
DeGrasse Tyson adds to this by saying that while he, like many people, has experienced "haunting experiences" in the past, he's yet to really find a phenomenon that's defied his complete knowledge of physics, maths, and astrophysics.
But that doesn't mean he doesn't get the very human urge to want to believe in the lingering dead.
"In that moment, there's a mystery, and it's kinda fun," he says.
"And that allows me to understand, and even embrace, the urge that people have to want there to be this deep mystery, such as ghosts of ancestors. I have a soft spot for what that psychological state is, because I've felt that intermittently, except I kept exploring and getting the answer."
You can download and listen to the whole segment at the BBC's website.
H/T: Real Clear Science