MIT is building a time-traveling dark matter detector

A team of physicists at MIT recently published a stunning research paper detailing their successful attempt to use entanglement and ‘quantum time reversal’ to create sensors capable of taking very deep measurements.

It sounds like a lot of science jargon, but the point is this could potentially lead to a legitimate ‘dark matter detector’, and it’s something that could revolutionize humanity’s understanding of everything.

In advance: Physics is a moving target. Because we are like fish in an aquarium, we don’t know where the water we are swimming is coming from or what lies behind the blurry shadows on the edge of our glass-paneled horizon.

Regards, humanoids

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To try to define our reality, we use the scientific method, the human imagination, and a lot of mathematics. But in the end, any theory is only as good as its ability to work with complementary theories.

Albert Einstein, for example, spent a lot of time harmonizing his theory of gravity with that of Isaac Newton.

In the modern era, physicists continue Einstein’s work by trying to reconcile his views on classical physics with recent discoveries in quantum mechanics.

But there is a problem. If we crush all the major theories together, we end up with an incomplete picture. Either a large part of the universe is made up of something we don’t yet know how to observe or measure, or Einstein was wrong.

That missing “something” has been dubbed “dark matter,” and the theory surrounding it is, arguably, the most accepted theory of the composition of the universe in modern physics.

Background: The goal of the MIT research is to build more accurate atomic clocks and pave the way for better quantum sensing.

Per the team’s research paper:

Potential applications include quantum sensors operating at limited bandwidths, and the principles we demonstrate could also advance fields such as quantum engineering, quantum measurement, and the search for new physics using optical transition atomic clocks.

But pushing the limits of quantum measurement is no easy task. The sensor we are talking about is designed to measure the small vibrations that occur in individual atoms.

The more limited we can measure these vibrations, the more information we can gain about the universe.

According to an MIT press release:

A certain type of atom vibrates at a certain and constant frequency which, if measured correctly, can serve as a very precise pendulum… But on the scale of a single atom, the laws of quantum mechanics take over, and the oscillations of atoms change like the face of a coin each time it is tossed.

In essence, it is very difficult to make quantum measurements because the quantum world does not obey the laws of classical physics.

A little deeper: Imagine that you toss a coin and photograph it while it is still in the air. In the image, the coin is completely horizontal so there is no way for you to determine whether it will most likely land on heads or tails.

In the classic world, you can only wait for the coins to hit the floor. To measure the results, you just have to look down. And, as long as nothing interferes with the coins, you can take all the time you want.

But the quantum world works a little differently. Imagine that you toss a coin in the air and take the same shot, but before your eyes can see the movement of the coin in the air, it will rearrange itself and you cannot determine where it landed.

And, because it is the most ironic field of scientific study, the peculiar nature of quantum physics is both a problem and a solution.

Because the coins undergo ‘quantum oscillations’ too fast for scientists to observe accurately, they had to find a way to buy time.

Sadly, there is a rule called the “Standard Quantum Limit” which basically says that the tools used by physicists to measure quantum vibrations are as good as they can be to date.

Ridiculous solution: If you can’t build a better measuring tool, use quantum mechanics to improve the signal you’re measuring.

The MIT researchers used quantum entanglement and quantum time reversal to amplify the signal and allow more measurements to occur during a given experiment.

Per press release:

The team used a laser system to trap atoms, then sent a blue “wrapped” light, which forced the atoms to oscillate in a correlated state. They allowed the entangled atoms to evolve forward in time, then exposed them to tiny magnetic fields, which introduced tiny quantum changes, slightly shifting the collective oscillations of the atoms.

Such a shift is impossible to detect with existing measurement tools. Instead, the team applied time reversal to enhance this quantum signal. To do this, they sent another red laser that stimulated the atoms to disentangle, as if they had evolved backwards in time.

Basically, that means researchers toss two coins in the air at the same time and use “quantum entanglement” to force them into a paradigm where whatever happens to one of them happens to the other.

Then the scientists used a magnetic field to strike the coin so that the spin changed, essentially reversing time and allowing them to take measurements in two temporals. direction.

It’s a little more complicated than that when it comes to actual atoms, but the coin analogy gets to the point.

Nerve retrieval: This is amazing! Scientists found a way to disturb the atoms so that they vibrate loud enough for us to detect them. In the wild, the ability to detect this level of disturbance allows us to “measure” hidden gravitational fields.

And that means the technique could legitimately lead to a complete dark matter detector.

Theoretically, dark matter particles should be ubiquitous throughout the universe. They might bounce off you (or maybe fly right through you?) as you read this article.

If scientists can push the limits of quantum sensing in such a way that they can detect the tiny changes in atomic vibrations that occur when dark matter particles interact with ordinary atoms, we might finally confirm Einstein’s theory.

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