Researcher Jim B. Tucker writes: “Work in quantum
mechanics has revealed what is known as the measurement problem. This
unassuming name describes a challenge that shakes our understanding of the
world to its core. Quantum theory says that particles on the small quantum
scale exist less as solid objects and more as probability waves. Only when an
object is measured, it seems, does its probability wave collapse to produce one
outcome.”
In what is called the double-slit experiment, “you have a
light source, along with a photographic plate that records the light that’s
emitted. Between them, you place a screen that blocks the light. If you cut a
slit in the screen for the light to pass through, then a fuzzy image is created
on the photographic plate that corresponds to the location of the slit.
“What happens if you cut a second slit in the screen? You
might think you would get two fuzzy images, matching the two slits, but you
don’t. Instead, the light appears to pass through the slits as waves, producing
an interference pattern on the photographic plate, of alternating light and
dark bands. Light sometimes acts as if it’s made up of particles, and other
times it acts like waves. But here’s the thing about the double-slit
experiment: when you turn down the light source so low that the light goes
through the screen one photon at a time, guess what happens? Somehow, you still
get the interference pattern. As theoretical physicist Paul Dirac said, ‘Each
photon then interferes only with itself.’ It’s as if each photon hasn’t made up
its mind about which slit to choose and goes through both of them
simultaneously.
“In case you think these results are simply due to the
strangeness of light, its particle-wave duality, you should know that the
double-slit experiment has now been done with electrons as well. In fact,
similar experiments have been done with neutrons, atoms, and even larger
molecules. Not just light but actual matter also acts like waves, seeming to go
in two places at once and interfering with itself. The famed physicist Richard
Feynman said the double-slit experiment was ‘impossible, absolutely impossible, to explain in any classical way’ and it ‘has
in it the heart of quantum mechanics.’
“Most of us learned in science class that atoms, the
building blocks of the universe, consist of electrons circling a nucleus like
small billiard balls. Quantum physicists tell us instead that electrons are
better seen as smears of probability, with their locations being potentials
rather than definite places. As strange as it may seem, it is only when an
electron is measured that its location goes from a smear to a specific spot.
“In the double-slit experiment, there is one thing that can
force the photons to make up their minds and go through one slit or the other.
If you set up sensors to observe them as they travel, each photon is seen going
through just one of the slits. The interference pattern on the photographic
plate disappears, and you get two fuzzy images corresponding to the two slits
instead. The observation leads to one path, one definite outcome, rather than
the two potential outcomes that existed before.
“Similarly, take a small particle that can travel down one
of the two paths, with a fifty-fifty chance of going down each one. According
to quantum theory, until someone looks to see which path it goes down, with a
measuring device for instance, all that can be said about the particle is that
it has the two probabilities. Common sense says it goes down a path but we just
don’t know which one until someone checks. Common sense, however, can be
misleading at the quantum level. Until the particle is observed, it does not
actually go down either path. It simply exists as a fifty-fifty probability
wave for going down each path.
“To say that light
and matter only exist as probability waves until they are observed raises the
question of what their existence in such a state would mean. As Werner
Heisenberg, one of the founders of quantum physics, noted: ‘The atoms or the
elementary particles themselves are not as real [as any phenomena in daily
life]; they form a world of potentialities or possibilities rather than one of
things or facts.’ With a measurement, one outcome snaps into place. ‘The
transition from the possible to the actual takes place during the act of
observation,’ to quote Heisenberg again. The measurement somehow causes one of
the two possibilities—or in other situations one of many possibilities—to
become the reality that is seen. Measuring something thus creates a reality
that did not exist before.
“Imagine that you do an experiment in which a photon can
take one of two paths, and a measuring device can be set up on one of the paths
to determine if the photon goes down it. The device failing to detect it on
that path would mean that the photon must have taken the other one.” Quantum
physicists examining this situation “found that observing the absence of a
photon on the first path collapses the wave function just as much as observing
the presence of it would. Since nothing is actually measured and only an
absence is observed, this indicates that the observation—not the measurement
itself—is the critical process in wave function collapse.’”
Moreover, Tucker writes: “it’s not the observing per se that
produces a result, it is the knowing
produced by the observing that does. By
seeing that a particle doesn’t go down one path, an observer can deduce that it
must have gone down the other one. Since no other result is possible, the
observer ‘knows’ which path the particle took, thereby collapsing the wave
function and producing the result.” As John Hopkins physicist Richard Conn
Henry wrote in the journal Nature,
‘The wave function is collapsed simply by your human mind seeing nothing.’ This
led him to conclude, ‘The Universe is entirely mental.’
Another physicist, Helmut Schmidt, conducted experiments “to
see if conscious effort could produce nonrandom results even if the effort occurred after the events had already been recorded.
He got positive results in the five studies he did, with odds against chance of
8,000 to 1. He recorded random events such as red and green light flashes, and
the series of flashes was then stored on a floppy disk. Days or months later,
the sequence was shown on a computer while a test subject tried to mentally
cause one of the colors to flash more. As long as no one inspected the
recordings beforehand, the mental efforts of the test subjects could cause the
results to be nonrandom, with more of one color appearing that would be
expected by chance. The test subjects’ success means that the collapse of the wave
function did not occur when the recording device initially measured the flashes
of light; the collapse only happened when the recordings were later observed.
Jim B. Tucker, Return to Life: Extraordinary Cases of Children Who Remember Past Lives
(St. Martin’s Press, 2013).