This video is brought to you by Wondrium. Stay tuned for a special offer for Arvin Ash viewers.
If you have followed physics news recently, you might have seen headlines such as:
“Physicists Create a Holographic Wormhole Using a Quantum Computer” and “A holographic wormhole
traversed in a quantum computer.” This is based on work by a team of
physicists led by Maria Spiropulu of CalTech. Did we really just make the first wormhole,
and in a lab? What did their work actually show? How exactly was this done? And what
does it mean for the future of humans being able to traverse vast distances
in the universe almost instantaneously through wormholes? Answers to those
question explained in simple words That’s coming up right now…
We have two main theories that describe nearly all observable phenomena. These are Quantum
mechanics which is the physics of the very small pioneered by scientists including Niels Bohr,
Erwin Schrodinger and Max Planck, and General Relativity which is the physics of the very
large pioneered by Albert Einstein. Both these theories work extremely well
in their two realms. They make predictions which can be verified, and have passed just
about all tests we have thrown at them. But the fundamental problem that still
remains after over 100 years now is the lack of compatibility between these two theories.
When we try to fit General Relativity into the quantum mechanical model, we get infinities which
are like nonsense results. Infinities are usually a red flag indicating that your theory is broken.
I have video detailing how and why this happens if you want to know more about it, right up here.
And quantum mechanics exists because classical mechanics like that of general relativity makes
no sense at the quantum level. I have video on that as well, if you want to know why that is.
The holy grail of physics has been and is the unification of these two realms
into something like a quantum theory of gravity, which we don’t currently have.
Einstein himself was working on this idea of unification until his last days.
In fact, he along with his collaborator, Nathan Rosen, in attempting to create this
unified theory of quantum gravity, published what is now called the "ER" paper for Einstein and Rosen.
Together they developed the concept of a certain type of a wormhole called an Einstein-Rosen (ER)
bridge. The idea is you start with a flat spacetime, then you add something superheavy
like a black hole that “breaks” spacetime, or something that creates a kind of hole in the
fabric of spacetime because of a theoretical singularity which would occur at its center,
a point of infinite mass density. Thus, you get a kind of tube-like structure
of spacetime that ends up at the singularity. Now if you have this same construction somewhere
else in space, then you could just imagine these two tubes connecting such that you don’t have
a singularity anymore, but rather a tube that connects one spacetime to the other spacetime,
this is a worm hole. It’s like a bridge from one part of spacetime to another.
Now it so happens, that just prior to publishing this paper, Einstein, Rosen and another
collaborator by the name of Boris Podolsky has published what is known as the EPR paper, in which
they argued that quantum mechanics is incomplete because of something called quantum entanglement.
This is a phenomenon in which a pair of particles can be created in such a way that their quantum
states are linked to each other. They are linked such that the act of measuring for
example the spin of one particle, instantly determines the spin of its entangled pair,
no matter how far apart they are. So the EPR paper argued that is not possible because it
would require information transfer instantly, or faster than the speed of light, breaking causality.
Now here it where it gets interesting. What if the wormhole from the ER paper,
and the phenomenon of entanglement from the EPR paper, were theoretically connected.
What if two entangled particles very far apart were exchanging information instantly
because they were intimately connected via a wormhole through which this information
could transfer through spacetime instantly? In 1997, physicist Juan Maldacena showed that
a system involving two sets of entangled particles was mathematically equivalent
to two black holes connected via a Wormhole. In 2013, Juan Maldecena along with physicist
Leonard Susskind proposed the ER = EPR conjecture. Basically they suggested
that the physics of Wormholes as described by the ER paper, was equivalent to the physics of
entanglement as described by the EPR paper. In other words, the conjecture is that entangled
particles are connected via a wormhole. So by creating a configuration of entangled
particles, we are also creating something equivalent to a wormhole. This is the basis of
the claim in the recent paper about how a wormhole was created in a lab using a quantum computer.
Quantum computers work thanks to entanglement, and so this is the
connection between them and wormholes. This does not that mean the authors
created a physical wormhole in spacetime, but rather using a quantum computer, they manipulated
quantum entangled particles in spacetime that simulated the behavior of a wormhole.
Remember that this is because the conjecture is that entangled particles
and wormholes can be described as being mathematically equivalent. So now let’s
look at how this experiment was actually done. According to general relativity, when anything
with mass or energy is introduced into a wormhole, it’s gravitational effect immediately closes it.
in order to keep a wormhole open and traversable, some form of negative energy or negative mass is
needed to provide a kind of force against the gravitational collapse of the wormhole,
to keep it open. Negative energy or mass is something not considered physically possible.
But this is not the case in our quantum system. Negative energy can be simulated in the system
by manipulating the electrical field to change the spin direction of the qubits.
So approximately, a propagating electric field could keep the quantum wormhole
open between entangled particles, simulating the effect of negative mass in space that
would be required to keep a real wormhole open. Ok so now, all the team needed was a way to set
up and manipulate entangled particles. This is where Google comes in. Their Sycamore quantum
computer can do precisely that type of thing. The researchers created an entangled state between
two sides of a quantum system using 7 qubits. A qubit is a basic unit of information in
quantum computers, just like a bit is a unit of information in a classical computer. The
difference is that unlike a classical bit which consists of a one or zero, on or off,
a qubit can consist of any state between a one and zero. It’s a superposition of the two.
The 7 qubits simulated a wormhole consisting of 7 pairs of particles. One set of particles acted
as the entrance of the wormhole and the other entangled set acted as the exit of the wormhole.
Two more maximally entangled qubits were used in this experiment, bringing the total to 9. One of
these qubits is called a “probe” and the other is called a “reference.” The probe was swapped
out with a particle located at the entrance of the wormhole. That probe’s possible states then
quickly got entangled with the states of the other particles at the entrance, spreading or scattering
its information among them, kind of like a drop of ink in water. This is roughly analogous to
a particle entering the mouth of a wormhole. Next the experimenters simulated the pulse of
negative energy needed to keep the wormhole open so that the information, or particle,
could be pushed through it. They did this by rotating the spin directions
of the qubits by changing the electric field. As the wormhole continued to evolve, the scrambled
information from the probe was transferred to the exit of the wormhole consisting of the 7 particles
on the other side. And then it unscrambled and focused on a single particle at the exit side of
the wormhole. This is analogous to the scrambled drop of ink in water turning back into a drop.
The researchers confirmed that information was transferred from the probe qubit at the
entrance to a particle at the exit by measuring the amount of entanglement between the reference
qubit and the particle at the exit. So this confirmed that information had indeed been
transferred via a mechanism which is similar to the physics of a traversable wormhole.
The surprise is not that the message made it across in some form,
but that it made it across unscrambled. In the ink analogy, the drop of ink was scattered,
but then was unscattered. This suggests the physics of a traversable wormhole was simulated.
The researcher said that in principle, if they had two quantum computers on opposites sides of earth,
a refined version of this experiment should be able to transmit quantum information from
one side to the other. So, if this is shown to be correct, that could be quite profound.
So, does this mean we might be able to someday traverse a real wormhole
in spacetime to travel instantly from one faraway place to another?
Well, keep in mind that this is a quantum mechanical simulation of a wormhole and not
a real wormhole in spacetime. They are just mathematically equivalent.
Most scientists are skeptical about how far we can push this analogy between entanglement in quantum
particles and real wormholes created in spacetime. Real wormholes today are still a fantasy.
What is my overall opinion? I think this experiment is not as
irrelevant as some scientists are saying. This is still a great step forward because it appears to
confirm some conjectures that attempt to combine quantum physics with general relativity, showing
that a unification may be possible and that these are not such crazy ideas. And this is the kind of
thinking and experimentation we probably need to make progress towards a quantum theory of gravity.
I think it’s good that people have crazy ideas, because sometimes they are right.
Einstein was considered crazy. Einstein thought quantum mechanics was crazy.
I can’t think of a single great paradigm-shifting idea that was
not considered crazy when first proposed. So let’s be skeptical, but also open minded!
Now the one thing I’ve been emphasizing is that this entire experiment including creating
the wormhole was done in a quantum computer. So if you really want to understand the details,
it would be important to know a little bit about how quantum computers work.
This is where I think you can benefit greatly from trying out Wondrium, today’s sponsor.
There are two terrific courses on the basics of quantum computers and how they work. Both
courses are taught in simple to understand language by one of my favorite educators,
Benjamin Schumacher of Kenyon College. The first course is simply called “Quantum
mechanics.” And covers the fundamentals on its way to explaining what makes quantum computers
so unique, especially for solving certain problems that would take centuries for standard computers.
The second course is called, “The science of information: from language to Black
holes.” It explains what qubits are and what quantum information actually means.
You’ll find this and many other wonderful courses like this on Wondrium taught by some of the best educators
in the world like Dr. Schumacher. That’s why I have been a member of Wondrium for a very long time,
and you’ll even find my testimonial at the bottom of their home page.
If you click the link in the description,
you’ll get a free trial. So Be sure to take advantage of this free offer.
That link is Wondrium.com/arvin. That’s wondrium.com/arvin. And you’ll be supporting this
channel when you sign up, so I can't thank you enough for that.
I’ll see you in the next video my friend.