Sydney: One of the most surprising predictions of physics is entanglement, a phenomenon in which objects can be linked to each other despite being some distance apart. The most famous examples of entanglement involve tiny bits of light (Photons), and less energy.
But Large Hadron Collider In Geneva, the world’s largest particle accelerator, an experiment called ATLAS, has detected entanglement in pairs of particles Top QuarkThe heaviest particle known to science.
What is confusion?
In everyday life we think of objects as either “separate” or “connected.” Two balls located a kilometer apart are separate. Two balls connected by a thread are connected.
When two objects are “entangled,” there’s no physical connection between them—but they’re not really separate either. You can take measurements of the first object, and that’s enough to know what the second object is doing before you even look at it.
The two objects form a single system, even though there is nothing connecting them. This is shown to work with photons located on opposite sides of the city.
The idea will be familiar to fans of the recent streaming series 3 Body Problems, based on Liu Cixin‘ is one of the sci-fi novels. In the show, aliens have sent a tiny supercomputer to Earth, in order to tamper with our technology and allow them to communicate with us. Because this tiny object is entangled with a twin on the alien homeworld, the aliens can communicate with it and control it – even though it’s four light years away.
that’s part of the story Science fiction: Entanglement doesn’t actually allow you to send signals faster than light. (It seems like entanglement allows you to do this, but according to scientists quantum physics That’s not possible. So far, all of our experiments are consistent with that prediction.)
But entanglement itself is real. It was first demonstrated for photons in the 1980s, a cutting-edge experiment at the time.
Today you can buy a box from a commercial provider that will spit out pairs of entangled photons. Entanglement is one of the properties described by quantum physics, and it is one of the properties that scientists and engineers are trying to use to create new technologies, such as quantum computing,
Since the 1980s, entanglement has been observed with atoms, some subatomic particles, and even small objects undergoing very faint vibrations. All of these examples are at low energies.
The new information from Geneva is that entanglement has been observed in pairs of particles called top quarks, where there is a vast amount of energy in a very small space.
So what are quarks then?
Matter is made up of molecules; molecules are made up of atoms; and atoms are made up of lighter particles called electrons orbiting a heavy nucleus at the center, like the Sun at the center of the solar system. We already knew this from experiments around 1911.
Then we learned that the nucleus was made of protons and neutrons, and by the 1970s we discovered that protons and neutrons were made of even smaller particles called quarks.
There are six types of quarks in total: the “up” and “down” quarks that make up protons and neutrons, and then four heavier quarks. The fifth quark, the “beauty” or “bottom” quark, is about four and a half times heavier than the proton, and when we found it we thought it was too heavy. But the sixth and final quark, the “top”, is a monster: slightly heavier than a tungsten atom, and 184 times the mass of a proton.
Nobody knows why the top quark is so massive. The top quark is the subject of intense study at the Large Hadron Collider for precisely this reason.
We think the very large mass might be a clue. Maybe the top quark is so massive because the top quark senses new forces, beyond the four we already know about. Or maybe it has some other connection to “new physics.”
We know that the laws of physics, as we currently understand them, are incomplete. Studying the behavior of the top quark could lead us to something new.
So does entanglement mean that top quarks are special?
Probably not. Quantum physics says that entanglement is common, and all kinds of things can become entangled.
But entanglement is also fragile. Many quantum physics experiments are carried out at ultra-cold temperatures, to avoid “bumping” into and disturbing the system. And so, until now, entanglement has been demonstrated in systems where scientists can set the right conditions to make measurements.
For technical reasons, the very large mass of the top quark makes it a good laboratory for studying entanglement. (The new ATLAS measurements would not have been possible for the other five types of quark.)
But top quark pairs won’t form the basis of any convenient new technology: you can’t pick up the Large Hadron Collider and move it around. Still, top quarks provide a new kind of tool to experiment with, and entanglement is interesting in its own right, so we’ll keep looking to see what else we find.
But Large Hadron Collider In Geneva, the world’s largest particle accelerator, an experiment called ATLAS, has detected entanglement in pairs of particles Top QuarkThe heaviest particle known to science.
What is confusion?
In everyday life we think of objects as either “separate” or “connected.” Two balls located a kilometer apart are separate. Two balls connected by a thread are connected.
When two objects are “entangled,” there’s no physical connection between them—but they’re not really separate either. You can take measurements of the first object, and that’s enough to know what the second object is doing before you even look at it.
The two objects form a single system, even though there is nothing connecting them. This is shown to work with photons located on opposite sides of the city.
The idea will be familiar to fans of the recent streaming series 3 Body Problems, based on Liu Cixin‘ is one of the sci-fi novels. In the show, aliens have sent a tiny supercomputer to Earth, in order to tamper with our technology and allow them to communicate with us. Because this tiny object is entangled with a twin on the alien homeworld, the aliens can communicate with it and control it – even though it’s four light years away.
that’s part of the story Science fiction: Entanglement doesn’t actually allow you to send signals faster than light. (It seems like entanglement allows you to do this, but according to scientists quantum physics That’s not possible. So far, all of our experiments are consistent with that prediction.)
But entanglement itself is real. It was first demonstrated for photons in the 1980s, a cutting-edge experiment at the time.
Today you can buy a box from a commercial provider that will spit out pairs of entangled photons. Entanglement is one of the properties described by quantum physics, and it is one of the properties that scientists and engineers are trying to use to create new technologies, such as quantum computing,
Since the 1980s, entanglement has been observed with atoms, some subatomic particles, and even small objects undergoing very faint vibrations. All of these examples are at low energies.
The new information from Geneva is that entanglement has been observed in pairs of particles called top quarks, where there is a vast amount of energy in a very small space.
So what are quarks then?
Matter is made up of molecules; molecules are made up of atoms; and atoms are made up of lighter particles called electrons orbiting a heavy nucleus at the center, like the Sun at the center of the solar system. We already knew this from experiments around 1911.
Then we learned that the nucleus was made of protons and neutrons, and by the 1970s we discovered that protons and neutrons were made of even smaller particles called quarks.
There are six types of quarks in total: the “up” and “down” quarks that make up protons and neutrons, and then four heavier quarks. The fifth quark, the “beauty” or “bottom” quark, is about four and a half times heavier than the proton, and when we found it we thought it was too heavy. But the sixth and final quark, the “top”, is a monster: slightly heavier than a tungsten atom, and 184 times the mass of a proton.
Nobody knows why the top quark is so massive. The top quark is the subject of intense study at the Large Hadron Collider for precisely this reason.
We think the very large mass might be a clue. Maybe the top quark is so massive because the top quark senses new forces, beyond the four we already know about. Or maybe it has some other connection to “new physics.”
We know that the laws of physics, as we currently understand them, are incomplete. Studying the behavior of the top quark could lead us to something new.
So does entanglement mean that top quarks are special?
Probably not. Quantum physics says that entanglement is common, and all kinds of things can become entangled.
But entanglement is also fragile. Many quantum physics experiments are carried out at ultra-cold temperatures, to avoid “bumping” into and disturbing the system. And so, until now, entanglement has been demonstrated in systems where scientists can set the right conditions to make measurements.
For technical reasons, the very large mass of the top quark makes it a good laboratory for studying entanglement. (The new ATLAS measurements would not have been possible for the other five types of quark.)
But top quark pairs won’t form the basis of any convenient new technology: you can’t pick up the Large Hadron Collider and move it around. Still, top quarks provide a new kind of tool to experiment with, and entanglement is interesting in its own right, so we’ll keep looking to see what else we find.
